Papers for Thursday, Feb 16 2023

We present the results from the HST WFC3 and ACS data on an archetypal galaxy undergoing ram pressure stripping (RPS), ESO 137-001, in the nearby cluster Abell 3627. ESO 137-001 is known to host a prominent stripped tail detected in many bands from X-rays, Halpha to CO. The HST data reveal significant features indicative of RPS such as asymmetric dust distribution and surface brightness as well as many blue young star complexes in the tail. We study the correlation between the blue young star complexes from HST, HII regions from Halpha (MUSE) and dense molecular clouds from CO (ALMA). The correlation between the HST blue star clusters and the HII regions is very good, while their correlation with the dense CO clumps are typically not good, presumably due in part to evolutionary effects. In comparison to the Starburst99+Cloudy model, many blue regions are found to be young (< 10 Myr) and the total star formation (SF) rate in the tail is 0.3 - 0.6 M_Sun/yr for sources measured with ages less than 100 Myr, about 40% of the SF rate in the galaxy. We trace SF over at least 100 Myr and give a full picture of the recent SF history in the tail. We also demonstrate the importance of including nebular emissions and a nebular to stellar extinction correction factor when comparing the model to the broadband data. Our work on ESO 137-001 demonstrates the importance of HST data for constraining the SF history in stripped tails.

Collapsing stars constitute the main black hole (BH) formation channel, and are occasionally associated with the launch of relativistic jets that power $ \gamma $-ray bursts (GRBs). Thus, collapsars offer an opportunity to infer the natal (before spin-up/down by accretion) BH spin directly from observations. We show that once the BH saturates with large-scale magnetic flux, the jet power is solely dictated by the BH spin and mass accretion rate. Recent core-collapse simulations by Halevi et al. 2022 and GRB observations favor stellar density profiles that yield a typical BH accretion rate, $ \dot{m} \approx 10^{-2} {\rm M_\odot~s^{-1}} $, which is weakly dependent on time. This leaves the BH spin as the main factor that governs the jet power. By comparing the resultant jet power to characteristic GRB luminosities, we find rapidly spinning BHs produce jets with excessive power, so that the majority of BHs associated with jets are born slowly spinning with a dimensionless spin $ a \simeq 0.2 $, or $ a \simeq 0.5 $ for wobbling jets. This result could be applied to the entire core-collapse BH population, unless an anti-correlation between the stellar magnetic field and angular momentum is present. In a companion paper (Jacquemin-Ide et al. 2023), we show that regardless of the natal spin, the extraction of BH rotational energy ultimately leads to inevitable spin-down to $ a \lesssim 0.2 $. These results are consistent with recent gravitational wave observations of BH mergers that indicate low spins. We verify our results by carrying out the first 3D general relativistic magnetohydrodynamic simulations of collapsar jets with characteristic GRB energies, powered by slowly spinning BHs. We find that jets of typical GRB power do not retain their energy during the propagation in the star, providing the first numerical indication that many jets might fail to generate a GRB.

We report spatially resolved dust properties of the quasar host galaxy BRI 1335-0417 at redshift $z = 4.4$ constrained by the ALMA observations. The dust temperature map, derived from a greybody fit to rest-frame 90 and 161 $\mu$m continuum images, shows a steep increase towards the centre, reaching $57.1 \pm 0.3$ K. Image decomposition analysis reveals the presence of a point source in both dust continuum images at the same position as the highest temperature peak and the optical quasar position, which we attribute to warm dust heated by an active galactic nucleus (AGN). We show that a model including this warm component along with cooler dust heated by star formation describes the global SED better than a single component model, with dust temperatures of 87.1$^{+34.1}_{-18.3}$ K (warm component) and 52.6$^{+10.3.}_{-11.0}$ K (cold component). The star formation rate (SFR) estimated from the cold dust component is $1700_{-400}^{+500} M_\odot$ yr$^{-1}$, a factor of three smaller than previous estimates due to a large AGN contribution ($53^{+14}_{-15}$%). The unresolved warm dust component also explains the steep temperature gradient, as the temperature profile derived after the point source subtraction is flat. We further show that AGN-host galaxy decomposition is critical for estimating SFR distribution, as point source subtraction reduces the estimated central SFR surface density $\Sigma_{\mathrm{SFR}}$ by over a factor of three. With this correction, spatially resolved measurements of $\Sigma_{\mathrm{SFR}}$ and the surface gas mass density $\Sigma_{\mathrm{gas}}$ form a roughly linear sequence in the Kennicutt-Schmidt diagram with a constant gas depletion time of 50-200 Myr.

The origin of the various outbursts of hard X-rays from magnetars, highly magnetized neutron stars, is still unknown. We identify instabilities in relativistic magnetospheres that can explain a range of X-ray flare luminosities. Crustal surface motions can twist the magnetar magnetosphere by shifting the frozen-in footpoints of magnetic field lines in current-carrying flux bundles. Axisymmetric (2D) magnetospheres exhibit strong eruptive dynamics, as to say, catastrophic lateral instabilities triggered by a critical footpoint displacement of $\psi_{\rm crit}\gtrsim\pi$. In contrast, our new three-dimensional (3D) twist models with finite surface extension capture important non-axisymmetric dynamics of twisted force-free flux bundles in dipolar magnetospheres. Besides the well-established global eruption resulting (as in 2D) from lateral instabilities, such 3D structures can develop helical, kink-like dynamics, and dissipate energy locally (confined eruptions). Up to $25\%$ of the induced twist energy is dissipated and available to power X-ray flares in powerful global eruptions, with most of our models showing an energy release in the range of the most common X-ray outbursts, $\lesssim 10^{43}$erg. Such events occur when significant energy builds up deeply buried in the dipole magnetosphere. Less energetic outbursts likely precede powerful flares due to intermittent instabilities and confined eruptions of a continuously twisting flux tube. Upon reaching a critical state, global eruptions produce the necessary Poynting-flux-dominated outflows required by models prescribing the fast radio burst production in the magnetar wind, for example, via relativistic magnetic reconnection or shocks.

We present the discovery of activity emanating from main-belt asteroid 2015 FW412, a finding stemming from the Citizen Science project Active Asteroids, a NASA Partner program. We identified a pronounced tail originating from 2015 FW412 and oriented in the anti-motion direction in archival Blanco 4-m (Cerro Tololo Inter-American Observatory, Chile) Dark Energy Camera (DECam) images from UT 2015 April 13, 18, 19, 21 and 22. Activity occurred near perihelion, consistent with the main-belt comets (MBCs), an active asteroid subset known for sublimation-driven activity in the main asteroid belt; thus 2015 FW412 is a candidate MBC. We did not detect activity on UT 2021 December 12 using the Inamori-Magellan Areal Camera and Spectrograph (IMACS) on the 6.5 m Baade telescope, when 2015 FW412 was near aphelion.

Visual inspections of the first optical rest-frame images from JWST have indicated a surprisingly high fraction of disk galaxies at high redshifts. Here we alternatively apply self-supervised machine learning to explore the morphological diversity at $z \geq 3$. Our proposed data-driven representation scheme of galaxy morphologies, calibrated on mock images from the TNG50 simulation, is shown to be robust to noise and to correlate well with physical properties of the simulated galaxies, including their 3D structure. We apply the method simultaneously to F200W and F356W galaxy images of a mass-complete sample ($M_*/M_\odot>10^9$) at $z \geq 3$ from the first JWST/NIRCam CEERS data release. We find that the simulated and observed galaxies do not populate the same manifold in the representation space from contrastive learning, partly because the observed galaxies tend to be more compact and more elongated than the simulated galaxies. We also find that about half the galaxies that were visually classified as disks based on their elongated images actually populate a similar region of the representation space than spheroids, which according to the TNG50 simulation is occupied by objects with low stellar specific angular momentum and non-oblate structure. This suggests that the disk fraction at $z > 3$ as evaluated by visual classification may be severely overestimated by misclassifying compact, elongated galaxies as disks. Deeper imaging and/or spectroscopic follow-ups as well as comparisons with other simulations will help to unambiguously determine the true nature of these galaxies.

We propose and apply a method to quantify the morphology of the large-scale ordered magnetic fields (B-fields) in galaxies. This method is adapted from the analysis of Event Horizon Telescope polarization data. We compute a linear decomposition of the azimuthal modes of the polarization field in radial galactocentric bins. We apply this approach to five low-inclination spiral galaxies with both far-infrared (FIR: $154~\mu$m ) dust polarimetric observations taken from the Survey of ExtragALactic magnetiSm with SOFIA (SALSA) and radio ($6$ cm) synchrotron polarization observations. We find that the main contribution to the B-field structure of these spiral galaxies comes from the $m=2$ and $m=0$ modes at FIR wavelengths and the $m=2$ mode at radio wavelengths. The FIR data tend to have a higher relative contribution from other modes than the radio data. The extreme case is NGC~6946: all modes contribute similarly in the FIR, while $m=2$ still dominates in the radio. The $m=2$ mode has a spiral structure and is directly related to the magnetic pitch angle, while $m=0$ has a constant B-field orientation. The average magnetic pitch angle in the FIR data is smaller and has greater angular dispersion than in the radio, indicating that the B-fields in the disk midplane traced by FIR dust polarization are more tightly wound and more chaotic than the B-field structure in the radio, which probes a larger volume. We argue that our approach is more flexible and model-independent than standard techniques, while still producing consistent results where directly comparable.

The spin of a newly formed black hole (BH) at the center of a massive star evolves from its natal value due to two competing processes: accretion of gas angular momentum that increases the spin, and extraction of BH angular momentum by outflows that decreases the spin. Ultimately, the final, equilibrium spin is set by the balance between both processes. In order for the BH to launch relativistic jets and power a $ \gamma $-ray burst (GRB), the BH magnetic field needs to be dynamically important. Thus, we consider the case of a magnetically arrested disk (MAD) driving the spin evolution of the BH. By applying the semi-analytic MAD BH spin evolution model of Lowell et al. (2023) to collapsars, we show that if the BH accretes $ \sim 20\% $ of its initial mass, its dimensionless spin inevitably reaches small values, $ a \lesssim 0.2 $. For such spins, and for mass accretion rates inferred from collapsar simulations, we show that our semi-analytic model reproduces the energetics of typical GRB jets, $L_{\rm jet}\sim10^{50}\,\,{\rm erg\,s^{-1}}$. We show that our semi-analytic model reproduces the nearly constant power of typical GRB jets. If the MAD onset is delayed, this allows powerful jets at the high end of the GRB luminosity distribution, $L_{\rm jet}\sim10^{52}\,\,{\rm erg\,s^{-1}}$, but the final spin remains low, $ a \lesssim 0.3 $. These results are consistent with the low spins inferred from gravitational wave detections of binary BH mergers. In a companion paper, Gottlieb et al. (2023), we use GRB observations to constrain the natal BH spin to be $ a \simeq 0.2 $.

With the growing number of binary black hole (BBH) mergers detected by LIGO/Virgo/KAGRA, several systems have become difficult to explain via isolated binary evolution, having components in the pair-instability mass gap, high orbital eccentricities, and/or spin-orbit misalignment. Here, we focus on GW191109\_010717, a BBH merger with component masses of $65^{+11}_{-11}$ and $47^{+15}_{-13}$ $\rm M_{\odot}$, and effective spin $-0.29^{+0.42}_{-0.31}$, which implies a spin-orbit misalignment of more than $\pi/2$ radians for at least one of its components. Besides its component masses being in the pair-instability mass gap, we show that isolated binary evolution is unlikely to reproduce the spin-orbit misalignment of GW191109 with high confidence. On the other hand, we demonstrate that BBHs dynamically assembled in dense star clusters would naturally reproduce the spin-orbit misalignment and the masses of GW191109, and the rates of GW191109-like events, if at least one of the components were to be a second-generation BH. Finally, we generalize our results to all the events with a measured negative effective spin, arguing that GW200225 also has a likely dynamical origin.

The continued operation of the Advanced LIGO and Advanced Virgo gravitational-wave detectors is enabling the first detailed measurements of the mass, spin, and redshift distributions of the merging binary black hole population. Our present knowledge of these distributions, however, is based largely on strongly parameteric models; such models typically assume the distributions of binary parameters to be superpositions of power laws, peaks, dips, and breaks, and then measure the parameters governing these "building block" features. Although this approach has yielded great progress in initial characterization of the compact binary population, the strong assumptions entailed leave it often unclear which physical conclusions are driven by observation and which by the specific choice of model. In this paper, we instead model the merger rate of binary black holes as an unknown autoregressive process over the space of binary parameters, allowing us to measure the distributions of binary black hole masses, redshifts, component spins, and effective spins with near-complete agnosticism. We find the primary mass spectrum of binary black holes to be doubly-peaked, with a fairly flat continuum that steepens at high masses. We identify signs of unexpected structure in the redshift distribution of binary black holes: a uniform-in-comoving volume merger rate at low redshift followed by a rise in the merger rate beyond redshift $z\approx 0.5$. Finally, we find that the distribution of black hole spin magnitudes is unimodal and concentrated at small but non-zero values, and that spin orientations span a wide range of spin-orbit misalignment angles but are also unlikely to be truly isotropic.

Many binary companions to the central stars of planetary nebulae (PNe) are found to be inflated, perhaps indicating that accretion onto the central star might occur during the PN phase. The discovery of a handful of nova eruptions and supersoft X-ray sources inside PNe supports this hypothesis. In this paper, we investigate the impact that hosting a steadily-accreting WD would have on the properties and evolution of a PN. By pairing the published accreting nuclear-burning WD models with radiation transfer simulations, we extract the time evolution of the emission line spectra and ionization properties of a PN that surrounds a 0.6$\rm M_{\odot}$ steadily nuclear-burning WD as a function of the mass accretion rate. We find that accreting WDs are able to form very extended, high excitation, [O III]-bright PNe, which are characterised by high nebular electron temperatures. Their properties remain almost invariant with time and their visibility time can be much longer compared to PNe powered by single WDs. We discuss the implications of our findings in explaining specific characteristics observed in PNe. Finally, we examine how accreting WDs affect the planetary nebula luminosity function (PNLF) by covering WD masses in the range of 0.5-0.8$\rm M_{\odot}$ and for various accretion rates within the steady accretion regime. We find that for all but the lowest accretion rates, the [O III]-luminosities are almost constant and clustered very close to the PNLF cut-off value. Our results suggest that mass-accreting WDs in interacting binaries might play a role in understanding the invariant cut-off of the PNLF.

The Halo Assembly in Lambda Cold Dark Matter: Observations in 7 Dimensions (HALO7D) survey measures the kinematics and chemical properties of stars in the Milky Way (MW) stellar halo to learn about the formation of our Galaxy. HALO7D consists of Keck II/DEIMOS spectroscopy and Hubble Space Telescope-measured proper motions of MW halo main sequence turn-off (MSTO) stars in the four CANDELS fields. HALO7D consists of deep pencil beams, making it complementary to other contemporary wide-field surveys. We present the [Fe/H] and [alpha/Fe] abundances for 113 HALO7D stars in the Galactocentric radial range of $\sim10-40$ kpc. Using the full 7D chemodynamical data (3D positions, 3D velocities, and abundances) of HALO7D, we measure the velocity anisotropy, $\beta$, of the halo velocity ellipsoid for each field and for different metallicity-binned subsamples. We find that two of the four fields have stars on very radial orbits while the remaining two have stars on more isotropic orbits. Separating the stars into high, mid, and low [Fe/H] bins at $-2.2$ dex and $-1.1$ dex for each field separately, we find differences in the anisotropies between the fields and between the bins; some fields appear dominated by radial orbits in all bins while other fields show variation between the [Fe/H] bins. These chemodynamical differences are evidence that the HALO7D fields have different fractional contributions from the progenitors that built up the MW stellar halo. Our results highlight the additional information that is available on smaller spatial scales when compared to results from a spherical average of the stellar halo.

We present a model for the full-sky diffuse Galactic synchrotron spectral index with an appropriate level of spatial structure for a resolution of 56 arcmin (to match the resolution of the Haslam 408 MHz data). Observational data at 408 MHz and 23 GHz have been used to provide spectral indices at a resolution of 5 degrees. In this work we make use of convolutional neural networks to provide a realistic proxy for the higher resolution information, in place of the genuine structure. Our deep learning algorithm has been trained using 14.4 arcmin observational data from the 1.4 GHz Parkes radio continuum survey. We compare synchrotron emission maps constructed by extrapolating the Haslam data using various spectral index maps, of different angular resolution, with the Global Sky Model. We add these foreground maps to a total emission model for a 21 cm intensity mapping experiment, then attempt to remove the foregrounds. The different models all display different spectral or spatial behaviour and so each provide a useful and different tool to the community for testing component separation techniques. We find that for an experiment operating using a cosine aperture taper beam with a primary Full Width at Half Maximum between 1.1 and 1.6 degrees, and the principal component analysis technique of foreground removal, there is a discernible difference between synchrotron spectral index models with a resolution larger than 5 degrees but that no greater resolution than 5 degrees is required.

Context. The Metis coronagraph is one of the remote-sensing instruments of the ESA/NASA Solar Orbiter mission. Metis is aimed at the study of the solar atmosphere and solar wind by simultaneously acquiring images of the solar corona at two different wavelengths; visible-light (VL) within a band ranging from 580 nm to 640 nm, and in the HI Ly-alpha 121.6 +/- 10 nm ultraviolet (UV) light. The visible-light channel includes a polarimeter with electro-optically modulating Liquid Crystal Variable Retarders (LCVRs) to measure the linearly polarized brightness of the K-corona to derive the electron density. Aims. In this paper, we present the first in-flight validation results of the Metis polarimetric channel together with a comparison to the on-ground calibrations. It is the validation of the first use in deep space (with hard radiation environment) of an electro-optical device: a liquid crystal-based polarimeter. Methods. We used the orientation of the K-corona's linear polarization vector during the spacecraft roll maneuvers for the in-flight calibration. Results. The first in-flight validation of the Metis coronagraph on-board Solar Orbiter shows a good agreement with the on-ground measurements. It confirms the expected visible-light channel polarimetric performance. A final comparison between the first pB obtained by Metis with the polarized brightness (pB) obtained by the space-based coronagraph LASCO and the ground-based coronagraph KCor shows the consistency of the Metis calibrated results.

A puzzling variety of superorbital modulations have been discovered in several supergiant High-Mass X-ray binaries (sgHMXBs). To investigate the mechanisms driving these superorbital modulations, we have analyzed long-term Neil Gehrels Swift Observatory (Swift) Burst Alert Telescope (BAT) observations of three sgHMXBs: 4U 1909+07, IGR J16418-4532 and IGR J16479-4514 and constructed their dynamic power spectra and superorbital intensity profiles. These Swift BAT observations are complemented by pointed Swift X-ray Telescope (XRT) and Nuclear Spectroscopic Telescope Array (NuSTAR) observations performed near the predicted maximum and minimum phase of a single superorbital cycle for each of these sources. The BAT dynamic power spectra show changes in the strength of the superorbital modulation on timescales of years, with either the peak at the fundamental frequency and/or the second harmonic present at different times for all three sources. The pointed Swift XRT and NuSTAR observations show no significant differences between the pulse profiles and spectral parameters at the superorbital maximum and minimum phase. This is likely due to the fact the superorbital modulation had weakened significantly during the times when the NuSTAR observations were carried out for all three sources. The results from the Swift XRT, BAT and NuSTAR analysis indicate the possible presence of multiple co-rotating interaction regions (CIRs) in the stellar winds of the supergiant stars, although a structured stellar wind from the supergiant star due to tidal oscillations cannot be ruled out.

Early dark energy (EDE) is an extension to the $\Lambda$CDM model, proposed to reduce the tension between the measurements of the Hubble constant $H_0$ from the cosmic microwave background (CMB) and from the local cosmic distance ladder. However, this model increases the $S_8$ tension between CMB and large scale structure measurements. Analyses of galaxy clustering and lensing correlation functions report a decreased preference for EDE and its effect on the Hubble tension. Smooth dark energy models affect growth of structure through the background expansion. In this work, we study the inclusion of a general, smooth late-time dark energy modification in combination with EDE and obtain constraints on EDE marginalized over the late-time expansion. We assess the impact on the $S_8$ and Hubble tensions. In order to generalize the late expansion, we use a late dark energy fluid model with a piecewise constant equation of state $w(z)$ over 3, 5 and 10 redshift bins in the window $z \in [0,3]$. We show that, when analyzing ACT and Planck CMB data combined with Pantheon supernovae, BAO from 6dF, SDSS and BOSS, Planck 2018 CMB lensing and Dark Energy Survey cosmic shear and clustering data, the inclusion of a general smooth dark energy modification at late times has no significant effect on $S_8$ and EDE parameter constraints. Using the aforementioned datasets, the EDE fraction constraint with late-time expansion marginalization is $f_\mathrm{EDE} = 0.067^{+0.019}_{-0.027}$ using 3 redshift bins, with similar results for 5 and 10 redshift bins. This work shows that in order to solve simultaneously the Hubble and $S_8$ tensions, one needs a mechanism for increasing the clustering of matter at late times different from a simple change in the background evolution of late dark energy. [Abridged]

We present the first results from a 100-day Swift, NICER and ground-based X-ray/UV/optical reverberation mapping campaign of the Narrow-Line Seyfert 1 Mrk 335, when it was in an unprecedented low X-ray flux state. Despite dramatic suppression of the X-ray variability, we still observe UV/optical lags as expected from disk reverberation. Moreover, the UV/optical lags are consistent with archival observations when the X-ray luminosity was >10 times higher. Interestingly, both low- and high-flux states reveal UV/optical lags that are 6-11 times longer than expected from a thin disk. These long lags are often interpreted as due to contamination from the broad line region, however the u band excess lag (containing the Balmer jump from the diffuse continuum) is less prevalent than in other AGN. The Swift campaign showed a low X-ray-to-optical correlation (similar to previous campaigns), but NICER and ground-based monitoring continued for another two weeks, during which the optical rose to the highest level of the campaign, followed ~10 days later by a sharp rise in X-rays. While the low X-ray countrate and relatively large systematic uncertainties in the NICER background make this measurement challenging, if the optical does lead X-rays in this flare, this indicates a departure from the zeroth-order reprocessing picture. If the optical flare is due to an increase in mass accretion rate, this occurs on much shorter than the viscous timescale. Alternatively, the optical could be responding to an intrinsic rise in X-rays that is initially hidden from our line-of-sight.

The low solar atmosphere is composed of mostly neutral particles, but the importance of the magnetic field for understanding observed dynamics means that interactions between charged and neutral particles play a very important role in controlling the macroscopic fluid motions. As the exchange of momentum between fluids, essential for the neutral fluid to effectively feel the Lorentz force, is through collisional interactions, the relative timescale of these interactions to the dynamic timescale determines whether a single-fluid model or, when the dynamic frequency is higher, the more detailed two-fluid model is the more appropriate. However, as many MHD phenomena fundamentally contain multi-time-scale processes, even large-scale, long-timescale motions can have an important physical contribution from two-fluid processes. In this review we will focus on two-fluid models, looking in detail at two areas where the multi-time-scale nature of the solar atmosphere means that two-fluid physics can easily develop: shock-waves and instabilities. We then connect these ideas to observations attempting to diagnose two-fluid behaviour in the solar atmosphere, suggesting some ways forward to bring observations and simulations closer together.

In many astrophysical systems, mixing between cool and hot temperature gas/plasma through Kelvin-Helmholtz-instability-driven turbulence leads to the formation of an intermediate temperature phase with increased radiative losses that drive efficient cooling. The solar atmosphere is a potential site for this process to occur with interaction between either prominence or spicule material and the solar corona allowing the development of transition region material with enhanced radiative losses. In this paper, we derive a set of equations to model the evolution of such a mixing layer and make predictions for the mixing-driven cooling rate and the rate at which mixing can lead to the condensation of the coronal material. These theoretical predictions are benchmarked against 2.5D MHD simulations. Applying the theoretical scalings to prominence threads or fading spicules, we found that as a mixing layer grows on their boundaries this would lead to the creation of transition region material with a cooling time of ~100 s, explaining the warm emission observed as prominence threads or spicules fade in cool spectral lines without the requirement for any heating. For quiescent prominences, dynamic condensation driven by the mixing process could restore ~18 per cent of the mass lost from a prominence through downflows. Overall, this mechanism of thermal energy loss through radiative losses induced by mixing highlights the importance for considering dynamical interaction between material at different temperatures when trying to understand the thermodynamic evolution of the cool material in the solar corona.

The upcoming new generation of optical spectrographs on four-meter-class telescopes will provide valuable opportunities for forthcoming galaxy surveys through their huge multiplexing capabilities, excellent spectral resolution, and unprecedented wavelength coverage. WEAVE is a new wide-field spectroscopic facility mounted on the 4.2 m William Herschel Telescope in La Palma. WEAVE-StePS is one of the five extragalactic surveys that will use WEAVE during its first five years of operations. It will observe galaxies using WEAVE MOS (~950 fibres across a field of view of ~3 deg2 on the sky) in low-resolution mode (R~5000, spanning the wavelength range 3660-9590 AA). WEAVE-StePS will obtain high-quality spectra (S/N ~ 10 per AA at R~5000) for a magnitude-limited (I_AB = 20.5) sample of ~25,000 galaxies, the majority selected at z>=0.3. The survey goal is to provide precise spectral measurements in the crucial interval that bridges the gap between LEGA-C and SDSS data. The wide area coverage of ~25 deg2 will enable us to observe galaxies in a variety of environments. The ancillary data available in each observed field (including X-ray coverage, multi-narrow-band photometry and spectroscopic redshift information) will provide an environmental characterisation for each observed galaxy. This paper presents the science case of WEAVE-StePS, the fields to be observed, the parent catalogues used to define the target sample, and the observing strategy chosen after a forecast of the expected performance of the instrument for our typical targets. WEAVE-StePS will go back further in cosmic time than SDSS, extending its reach to encompass more than ~6 Gyr, nearly half of the age of the Universe. The spectral and redshift range covered by WEAVE-StePS will open a new observational window by continuously tracing the evolutionary path of galaxies in the largely unexplored intermediate-redshift range.

We explore evolution in the dust-to-gas ratio with density within four well-resolved Local Group galaxies - the LMC, SMC, M31, and M33. We do this using new ${\it Herschel}$ maps, which restore extended emission that was missed by previous ${\it Herschel}$ reductions. This improved data allows us to probe the dust-to-gas ratio across 2.5 orders of magnitude in ISM surface density. We find significant evolution in the dust-to-gas ratio, with dust-to-gas varying with density within each galaxy by up to a factor 22.4. We explore several possible reasons for this, and our favored explanation is dust grain growth in denser regions of ISM. We find that the evolution of the dust-to-gas ratio with ISM surface density is very similar between M31 and M33, despite their large differences in mass, metallicity, and star formation rate; conversely, we find M33 and the LMC to have very different dust-to-gas evolution profiles, despite their close similarity in those properties. Our dust-to-gas ratios address previous disagreement between UV- and FIR-based dust-to-gas estimates for the Magellanic Clouds, removing the disagreement for the LMC, and considerably reducing it for the SMC - with our new dust-to-gas measurements being factors of 2.4 and 2.0 greater than the previous far-infrared estimates, respectively. We also observe that the dust-to-gas ratio appears to fall at the highest densities for the LMC, M31, and M33; this is unlikely to be an actual physical phenomenon, and we posit that it may be due to a combined effect of dark gas, and changing dust mass opacity.

We report the radio and high-energy properties of a new outburst from the radio-loud magnetar 1E 1547.0$-$5408. Following the detection of a short burst from the source with Swift-BAT on 2022 April 7, observations by NICER detected an increased flux peaking at $(6.0 \pm 0.4) \times 10^{-11}$ erg s$^{-1}$ cm$^{-2}$ in the soft X-ray band, falling to the baseline level of $1.7\times10^{-11}$ erg s$^{-1}$ cm$^{-2}$ over a 17-day period. Joint spectroscopic measurements by NICER and NuSTAR indicated no change in the hard non-thermal tail despite the prominent increase in soft X-rays. Observations at radio wavelengths with Murriyang, the 64-m Parkes radio telescope, revealed that the persistent radio emission from the magnetar disappeared at least 22 days prior to the initial Swift-BAT detection and was re-detected two weeks later. Such behavior is unprecedented in a radio-loud magnetar, and may point to an unnoticed slow rise in the high-energy activity prior to the detected short-bursts. Finally, our combined radio and X-ray timing revealed the outburst coincided with a spin-up glitch, where the spin-frequency and spin-down rate increased by $2 \pm 1$ $\mu$Hz and $(-2.4 \pm 0.1) \times 10^{-12}$ s$^{-2}$ respectively. A linear increase in spin-down rate of $(-2.0 \pm 0.1) \times 10^{-19}$ s$^{-3}$ was also observed over 147 d of post-outburst timing. Our results suggest that the outburst may have been associated with a reconfiguration of the quasi-polar field lines, likely signalling a changing twist, accompanied by spatially broader heating of the surface and a brief quenching of the radio signal, yet without any measurable impact on the hard X-ray properties.

The growth of large-scale structure, as revealed in the anisotropic of clustering of galaxies in the low redshift Universe, provides a stringent test of our cosmological model. The strongest current constraints come from the BOSS and eBOSS surveys, with uncertainties on the amplitude of clustering of less than 10 per cent. A number of different approaches have been taken to fitting this signal, leading to apparently discrepant conclusions about the amplitude of fluctuations at late times. We compare in some detail two of the leading approaches, one based on a fitting a template cosmology whose amplitude and length scales are allowed to float with one based on a more traditional forward modeling approach, when fitting to the BOSS DR12 data. Holding the input data, scale cuts, window functions and modeling framework fixed we are able to isolate the cause of the differences and discuss the implications for future surveys.

Understanding the temporal characteristics of data from low frequency radio telescopes is of importance in devising suitable calibration strategies. Application of time series analysis techniques to data from radio telescopes can reveal a wealth of information that can aid in calibration. In this paper, we investigate singular spectrum analysis (SSA) as an analysis tool for radio data. We show the intimate connection between SSA and Fourier techniques. We develop the relevant mathematics starting with an idealised periodic dataset and proceeding to include various non-ideal behaviours. We propose a novel technique to obtain long-term gain changes in data, leveraging the periodicity arising from sky drift through the antenna beams. We also simulate several plausible scenarios and apply the techniques to a 30-day time series data collected during June 2021 from SITARA - a short-spacing two element interferometer for global 21-cm detection. Applying the techniques to real data, we find that the first reconstructed component - the trend - has a strong anti-correlation with the local temperature suggesting temperature fluctuations as the most likely origin for the observed variations in the data. We also study the limitations of the calibration in the presence of diurnal gain variations and find that such variations are the likely impediment to calibrating SITARA data with SSA.

The position of the peak of the matter power spectrum, the so-called turnover scale, is set by the horizon size at the epoch of matter-radiation equality. It can easily be predicted in terms of the physics of the Universe in the relativistic era, and so can be used as a standard ruler, independent of other features present in the matter power spectrum, such as baryon acoustic oscillations (BAO). We use the distribution of quasars measured by the extended Baryon Oscillation Spectroscopic Survey (eBOSS) to determine the turnover scale in a model-independent fashion statistically. We avoid modelling the BAO by down-weighting affected scales in the covariance matrix using the mode deprojection technique. We measure the wavenumber of the peak to be $k_\mathrm{TO} = \left( 17.7^{+1.9}_{-1.7} \right) \times 10^{-3}h/\mathrm{Mpc}$, corresponding to a dilation scale of $ D_\mathrm{V}(z_\mathrm{eff} = 1.48) = \left(31.5^{+3.0}_{-3.4}\right)r_\mathrm{H}$. This is not competitive with current BAO distance measures in terms of determining the expansion history but does provide a useful cross-check. We combine this measurement with low-redshift distance measurements from type-Ia supernova data from Pantheon and BAO data from eBOSS to make a sound-horizon free estimate of the Hubble-Lema\^itre parameter and find it to be $H_0=64.8^{+8.4}_{-7.8} \ \mathrm{km/s/Mpc}$ with Pantheon, and $H_0=63.3^{+8.2}_{-6.9} \ \mathrm{km/s/Mpc}$ with eBOSS BAO. We make predictions for the measurement of the turnover scale by the Dark Energy Spectroscopic Instrument (DESI) survey, the Maunakea Spectroscopic Explorer (MSE) and MegaMapper, which will make more precise and accurate distance determinations.

We construct the eROSITA X-ray catalog of radio galaxies discovered by the WERGS survey that is made by the cross-matching of the wide-area Subaru/HSC optical survey and VLA/FIRST 1.4 GHz radio survey. We find 393 eROSITA detected radio galaxies in the 0.5--2 keV band in the eFEDS field covering 140~deg$^2$. Thanks to the wide and medium depth eFEDS X-ray survey, the sample contains the rare and most X-ray luminous radio galaxies above the knee of the X-ray luminosity function, spanning 44<log L(0.5-2keV,abs)<46.5 at $1<z<4$. Based on the X-ray properties obtained by the spectral fitting, 37 sources show obscured AGN signature with $\log (N_\mathrm{H}/\mathrm{cm}^{-2})>22$. Those obscured and radio AGN reside in $0.4<z<3.2$, indicating that they are obscured counterparts of the radio-loud quasar, which are missed in the previous optical quasar surveys. By combining radio and X-ray luminosities, the jet production efficiency $\eta_\mathrm{jet}$ is investigated, and we find 14 sources with extremely high jet production efficiency at $\eta_\mathrm{jet}\approx1$. This high $\eta_\mathrm{jet}$ value might be a result of 1) the decreased radiation efficiency of $\eta_\mathrm{rad}<0.1$ due to the low accretion rate for those sources and/or 2) the boosting due to the decline of $L_\mathrm{bol}$ by a factor of 10--100 by keeping $P_\mathrm{jet}$ constant in the previous Myr, indicating the experience of the AGN feedback. Finally, inferring the BH masses from the stellar-mass, we find that X-ray luminous sources show the excess of the radio emission with respect to the value estimated from the fundamental plane. Such radio emission excess cannot be explained by the Doppler booming alone, and therefore disk-jet connection of X-ray luminous eFEDS-WERGS is fundamentally different from the conventional fundamental plane which mainly covers low accretion regime.

We report the analysis of microlensing event OGLE-2017-BLG-1038, observed by the Optical Gravitational Lensing Experiment, Korean Microlensing Telescope Network, and Spitzer telescopes. The event is caused by a giant source star in the Galactic Bulge passing over a large resonant binary lens caustic. The availability of space-based data allows the full set of physical parameters to be calculated. However, there exists an eightfold degeneracy in the parallax measurement. The four best solutions correspond to very-low-mass binaries near ($M_1 = 170^{+40}_{-50} M_J$ and $M_2 = 110^{+20}_{-30} M_J$), or well below ($M_1 = 22.5^{+0.7}_{-0.4} M_J$ and $M_2 = 13.3^{+0.4}_{-0.3} M_J$) the boundary between stars and brown dwarfs. A conventional analysis, with scaled uncertainties for Spitzer data, implies a very-low-mass brown dwarf binary lens at a distance of 2 kpc. Compensating for systematic Spitzer errors using a Gaussian process model suggests that a higher mass M-dwarf binary at 6 kpc is equally likely. A Bayesian comparison based on a galactic model favors the larger-mass solutions. We demonstrate how this degeneracy can be resolved within the next ten years through infrared adaptive-optics imaging with a 40 m class telescope.

The paper presents an analysis of multi-wavelength data of a nearby star-forming site IC 5146 dark Streamer (d $\sim$600 pc), which has been treated as a single and long filament, fl. Two hub-filament systems (HFSs) are known toward the eastern and the western ends of fl. Earlier published results favor the simultaneous evidence of HFSs and the end-dominated collapse (EDC) in fl. Herschel column density map (resolution $\sim$13$''$.5) reveals two intertwined sub-filaments (i.e., fl-A and fl-B) toward fl, displaying a nearly double helix-like structure. This picture is also supported by the C$^{18}$O(3-2) emission. The scenario "fray and fragment" may explain the origin of intertwined sub-filaments. In the direction of fl, two cloud components around 2 and 4 km s$^{-1}$ are depicted using the $^{13}$CO(1-0) and C$^{18}$O(1-0) emission, and are connected in velocity space. The HFSs are spatially found at the overlapping areas of these cloud components and can be explained by the cloud-cloud collision scenario. Non-thermal gas motion in fl with larger Mach number is found. The magnetic field position angle measured from the filament's long axis shows a linear trend along the filament. This signature is confirmed in the other nearby EDC filaments, presenting a more quantitative confirmation of the EDC scenario. Based on our observational outcomes, we witness multiple processes operational in IC 5146 Streamer. Overall, the Streamer can be recognized as the first reliable candidate of edge collapse, HFSs, and intertwined sub-filaments together.

We report on pulse profile decomposition analysis of a bright transient X-ray pulsar 1A 0535+262 using the broadband Insight-HXMT observations during a giant outburst of the source in 2020. We show that the observed pulse profile shape can be described in terms of a combination of two symmetric single-pole contributions for wide range of energies and luminosities for a fixed geometry defining basic geometry of the pulsar. This corresponds to a slightly distorted dipole magnetic field, i.e., one pole has to be offset by $\sim 12^{\circ}$ from the antipodal position of the other pole. We reconstruct the intrinsic beam patterns of the pulsar assuming the geometry recovered from the decomposition analysis, and find evidence for a transition between "pencil" and "fan" beams in energy ranges above the cyclotron line energy which can be interpreted as transition from sub- to super-critical accretion regimes associated with onset of an accretion column. At lower energies the beam pattern appears, however, to be more complex, and contains substantial "fan" beam and an additional "pencil" beam component at all luminosities. The latter is not related to the accretion rate and is stronger in the fading phase of the outburst. We finally discuss results in context of other observational and theoretical findings earlier reported for the source in the literature.

Local Group (LG), the nearest and most complete galactic environment, provides valuable information on the formation and evolution of the Universe. Studying galaxies of different sizes, morphologies, and ages can provide this information. For this purpose, we chose the And\,IX dSph galaxy, which is one of the observational targets of the Isaac Newton Telescope (INT) survey. A total of 50 long-period variables (LPVs) were found in And\,IX in two filters, Sloan $i'$ and Harris $V$ at a half-light radius of 2.5 arcmin. The And\,IX's star formation history (SFH) was constructed with a maximum star formation rate (SFR) of about $0.00082\pm0.00031$ M$_\odot$ yr$^{-1}$, using LPVs as a tracer. The total mass return rate of LPVs was calculated based on the spectral energy distribution (SED) of about $2.4\times10^{-4}$ M$_\odot$ yr$^{-1}$. The distance modulus of $24.56_{-0.15}^{+0.05}$ mag was estimated based on the tip of the red giant branch (TRGB).

Night Sky Background (NSB) is a complex phenomenon, consisting of all light detected by Imaging Atmospheric Cherenkov Telescopes (IACTs) not attributable to Cherenkov light emission. Understanding the effect of NSB on cameras for the next-generation Cherenkov Telescope Array (CTA) is important, as it affects the systematic errors on observations, the energy threshold, the thermal control of the cameras and the ability of the telescopes to operate under partial moonlight conditions. This capacity to observe under partial moonlight conditions is crucial for the CTA transient science programme, as it substantially increases the potential observing time. Using tools initially developed for H.E.S.S. (in combination withthe prototype CTA analysis package ctapipe) we will present predictions for the NSB present in images taken by the CTA Small Sized Telescope Camera (SSTCAM), showing that SSTCAM will likely be able to meet the associated CTA requirements. Additionally, we calculate the potential observing time gain by operating under high NSB conditions.

Starless cores represent the initial stage of evolution toward (proto)star formation, and a subset of them, known as prestellar cores, with high density (~ 10^6 cm^-3 or higher) and being centrally concentrated are expected to be embryos of (proto)stars. Determining the density profile of prestellar cores, therefore provides an important opportunity to gauge the initial conditions of star formation. In this work, we perform rigorous modeling to estimate the density profiles of three nearly spherical prestellar cores among a sample of five highly dense cores detected by our recent observations. We employed multi-scale observational data of the (sub)millimeter dust continuum emission including those obtained by SCUBA-2 on the JCMT with a resolution of ~5600 au and by multiple ALMA observations with a resolution as high as ~480 au. We are able to consistently reproduce the observed multi-scale dust continuum images of the cores with a simple prescribed density profile, which bears an inner region of flat density and a r^-2 profile toward the outer region. By utilizing the peak density and the size of the inner flat region as a proxy for the dynamical stage of the cores, we find that the three modeled cores are most likely unstable and prone to collapse. The sizes of the inner flat regions, as compact as ~500 au, signify them being the highly evolved prestellar cores rarely found to date.

The giant planets were the first to form and hold the key to unveiling the solar system's formation history in their interiors and atmospheres. Furthermore, the unique conditions present in the interiors of the giant planets make them natural laboratories for exploring different elements under extreme conditions. We are at a unique time to study these planets. The missions Juno to Jupiter and Cassini to Saturn have provided invaluable information to reveal their interiors like never before, including extremely accurate gravity data, atmospheric abundances and magnetic field measurements that revolutionised our knowledge of their interior structures. At the same time, new laboratory experiments and modelling efforts also improved, and statistical analysis of these planets is now possible to explore all the different conditions that shape their interiors. We review the interior structure of Jupiter, Saturn, Uranus and Neptune, including the need for inhomogeneous structures to explain the data, the problems unsolved and the effect that advances in our understanding of their internal structure have on their formation and evolution.

Any missions to catch 1I/'Oumuamua have the daunting challenge of generating higher hyperbolic excess speeds than the interstellar object's own, i.e. $>$ 26.3 $kms^{-1}$ with respect to the Sun. To accomplish this task using chemical propulsion, previous papers have investigated a Solar Oberth manoeuvre and alternatively a Jupiter Oberth, these options requiring a thrust from the chemical rocket at perihelion/perijove respectively, points at which the available velocity increment ($\Delta V$) results in maximum augmentation of the kinetic energy of the spacecraft. In this paper we unravel the specifics of a mission requiring a JOM or optionally a passive Jupiter encounter, i.e. with no thrust, the latter having so far not been addressed by Project Lyra. Whereas the previous papers were feasibility studies, this paper delves into what would be achievable with a Jupiter encounter (without any preceding gravitational assists from the inner planets), using currently available off-the-shelf solid and liquid rocket stages and assuming the NASA Space Launch System Block 2 can be deployed. Optimal Launch dates are found to lie in the years 2030, 2031 and 2032 with resulting mission durations of around 30-40 years, depending on the particular number and combination of stages exploited. Payload masses to 'Oumuamua of 860kg can readily be accomplished with a duration of 43 or so years, assuming a Centaur D and STAR 48B combination, the latter booster being ignited at perijove. On the other hand if two Centaur Ds are utilised instead of just one, retaining the STAR 48BV for the JOM, 35 years are evinced for the same mass. Furthermore, for lower payloads of $\sim{100}$kg, the flight duration can be cut accordingly to 31 years, with the additional benefit of requiring no burn at Jupiter.

We present a photometric study of the resolved stellar populations in And\,IX, the closest satellite to the M31, a metal-poor and low-mass dwarf spheroidal galaxy. We estimate a distance modulus of $24.56_{-0.15}^{+0.05}$ mag based on the tip of the red giant branch (TRGB). By probing the variability of asymptotic giant branch stars (AGB), we study the star formation history of And\,IX. We identified 50 long period variables (LPVs) in And\,IX using the Isaac Newton Telescope (INT) in two filters, Sloan $i'$ and Harris $V$. In this study, we selected LPVs within two half-light radii with amplitudes in the range of $0.2-2.20$ mag. It is found that the peak of star formation reaches $\sim$ $8.2\pm3.1\times10^{-4}$ M$\textsubscript{\(\odot\)}$ yr$^{-1}$ at $\approx 6$ Gyr ago. Our findings suggest an outside-in galaxy formation scenario for And\,IX with a quenching occurring $3.80_{-0.27}^{+1.82}$ Gyr ago with the SFR in the order of $2.0\times10^{-4}$ M$\textsubscript{\(\odot\)}$ yr$^{-1}$ at redshift < $0.5$. We calculate the total stellar mass by integrating the star formation rate (SFR) within two half-light radii $\sim$ $3.0\times10^5$ M$\textsubscript{\(\odot\)}$. By employing the spectral energy distribution (SED) fitting for observed LPVs in And\,IX, we evaluate the mass-loss rate in the range of $10^{-7}$ $\leq$ $\dot{M}$ $\leq$ $10^{-5}$ M$\textsubscript{\(\odot\)}$ yr$^{-1}$. Finally, we show that the total mass deposition to the interstellar medium (ISM) is $\sim$ $2.4\times10^{-4}$ M$\textsubscript{\(\odot\)}$ yr$^{-1}$ from the C- and O-rich type of dust-enshrouded LPVs. The ratio of the total mass returned to the ISM by LPVs to the total stellar mass is $\sim 8.0\times10^{-10}$ yr$^{-1}$, and so at this rate, it would take $\sim$ 1 Gyr to reproduce this galaxy

The high redhsift blazars powered by supermassive black holes with masses exceeding $10^9\:M_\odot$ have the highest jet power and luminosity and are important probes to test the physics of relativistic jets at the early epochs of the Universe. We present a multi-frequency spectral and temporal study of high redshift blazar PKS 0537-286 by analyzing data from Fermi-LAT, NuSTAR Swift XRT and UVOT. Although the time averaged $\gamma$-ray spectrum of the source is relatively soft (indicating the high-energy emission peak is below the GeV range), several prominent flares were observed when the spectrum hardened and the luminosity increased above $10^{49}\:{\rm erg\:s^{-1}}$. The X-ray emission of the source varies in different observations and is characterised by a hard spectrum $\leq1.38$ with a luminosity of $>10^{47}\:{\rm erg\:s^{-1}}$. The broadband spectral energy distribution in the quiescent and flaring periods was modeled within a one-zone leptonic scenario assuming different locations of the emission region and considering both internal (synchrotron radiation) and external (from the disk, broad-line region and dusty torus) photon fields for the inverse Compton scattering. The modeling shows that the most optimistic scenario, from the energy requirement point of view, is when the jet energy dissipation occurs within the broad-line region. The comparison of the model parameters obtained for the quiescent and flaring periods suggests that the flaring activities are most likely caused by the hardening of the emitting electron spectral index and shifting of the cut-off energy to higher values.

Globular clusters have been widely studied in terms of light element variations present in their different stellar populations. However, the nature of the polluter(s) responsible for this phenomenon is still debated. The study of heavy elements and their relation to light ones can provide further constraints. In particular, we aim to explore the possible contribution of asymptotic giant branch stars of different stellar masses to the internal pollution in the cluster. We derive abundances of elements from different nucleosynthetic chains, such as Na, Mg, Ca, Sc, Cu, Y, and Ba. We did not find clear relations between the light s-process elements (represented by Y II) or heavy ones (represented by Ba II) with light elements (Li, Na or Al). This indicates that the polluter(s) responsible for the Na (Al) or Li production does not produce large amounts of Y II and Ba II. Furthermore, the comparison with models discards a possible significant contribution to the cluster pollution from AGB stars with masses lower than 5M$_{\odot}$. In addition, we found a potential CH-star in our sample.

Blazars are active galactic nuclei with relativistic jets pointed almost directly at Earth. Blazars are characterized by strong, apparently stochastic flux variability at virtually all observed wavelengths and timescales, from minutes to years, the physical origin of which is still poorly understood. In the high-energy gamma-ray band, the Large Area Telescope aboard the Fermi space telescope (Fermi-LAT) has conducted regular monitoring of thousands of blazars since 2008. Deep learning can help uncover structure in gamma-ray blazars' complex variability patterns that traditional methods based on parametric statistical modeling or manual feature engineering may miss. In this work, we propose using a self-supervised Transformer encoder architecture to construct an effective representation of blazar gamma-ray variability. Measurement errors, upper limits, and missing data are accommodated using learned encodings. The model predicts a set of quantiles for the flux probability distribution at each time step, an architecture naturally suited for describing data generated by a stochastic process. As a proof of concept for how the model output can be analyzed to extract scientifically relevant information, a preliminary search for weekly-timescale time-reversal asymmetry in gamma-ray blazar light curves was conducted, finding no significant evidence for asymmetry.

We report the characterization of 28 low-mass ($0.02\mathrm{~M_\odot}\le\mathrm{~M_{2}}\le0.25\mathrm{~M_\odot}$) companions to $\textit{Kepler}$ objects of interest (KOIs), eight of which were previously designated confirmed planets. These objects were detected as transiting companions to Sun-like stars (G and F dwarfs) by the $\textit{Kepler}$ mission and are confirmed as single-lined spectroscopic binaries in the current work using the northern multiplexed Apache Point Observatory Galactic Evolution Experiment near-infrared spectrograph (APOGEE-N) as part of the third and fourth Sloan Digital Sky Surveys. We have observed hundreds of KOIs using APOGEE-N and collected a total of 43,175 spectra with a median of 19 visits and a median baseline of $\sim1.9$ years per target. We jointly model the $\textit{Kepler}$ photometry and APOGEE-N radial velocities to derive fundamental parameters for this subset of 28 transiting companions. The radii for most of these low-mass companions are over-inflated (by $\sim10\%$) when compared to theoretical models. Tidally locked M dwarfs on short period orbits show the largest amount of inflation, but inflation is also evident for companions that are well separated from the host star. We demonstrate that APOGEE-N data provides reliable radial velocities when compared to precise high-resolution spectrographs that enable detailed characterization of individual systems and the inference of orbital elements for faint ($H>12$) KOIs. The data from the entire APOGEE-KOI program is public and presents an opportunity to characterize an extensive subset of the binary population observed by $\textit{Kepler}$.

We confirm the planetary nature of two gas giants discovered by TESS to transit M dwarfs with stellar companions at wide separations. TOI-3984 A ($J=11.93$) is an M4 dwarf hosting a short-period ($4.353326 \pm 0.000005$ days) gas giant ($M_p=0.14\pm0.03~\mathrm{M_{J}}$ and $R_p=0.71\pm0.02~\mathrm{R_{J}}$) with a wide separation white dwarf companion. TOI-5293 A ($J=12.47$) is an M3 dwarf hosting a short-period ($2.930289 \pm 0.000004$ days) gas giant ($M_p=0.54\pm0.07~\mathrm{M_{J}}$ and $R_p=1.06\pm0.04~\mathrm{R_{J}}$) with a wide separation M dwarf companion. We characterize both systems using a combination of ground-based and space-based photometry, speckle imaging, and high-precision radial velocities from the Habitable-zone Planet Finder and NEID spectrographs. TOI-3984 A b ($T_{eq}=563\pm15$ K and $\mathrm{TSM}=138_{-27}^{+29}$) and TOI-5293 A b ($T_{eq}=675_{-30}^{+42}$ K and $\mathrm{TSM}=92\pm14$) are two of the coolest gas giants among the population of hot Jupiter-sized gas planets orbiting M dwarfs and are favorable targets for atmospheric characterization of temperate gas giants and three-dimensional obliquity measurements to probe system architecture and migration scenarios.

Since 2015 the LIGO and Virgo interferometers have detected gravitational waves from almost one hundred coalescences of compact objects (black holes and neutron stars). This article presents the results of a search performed with data from the ANTARES telescope to identify neutrino counterparts to the gravitational wave sources detected during the third LIGO/Virgo observing run and reported in the catalogues GWTC-2, GWTC-2.1, and GWTC-3. This search is sensitive to all-sky neutrinos of all flavours and of energies $>100\,$GeV, thanks to the inclusion of both track-like events (mainly induced by $\nu_\mu$ charged-current interactions) and shower-like events (induced by other interaction types). Neutrinos are selected if they are detected within $\pm 500\,$s from the GW merger and with a reconstructed direction compatible with its sky localisation. No significant excess is found for any of the 80 analysed GW events, and upper limits on the neutrino emission are derived. Using the information from the GW catalogues and assuming isotropic emission, upper limits on the total energy $E_{\rm tot, \nu}$ and on the fraction of the total energy budget $f_\nu = E_{\rm tot, \nu}/E_{\rm rad}$ emitted as neutrinos of all flavours are also computed. Finally, a stacked analysis of all the 72 binary black hole mergers (respectively the 7 neutron star - black hole merger candidates) has been performed to constrain the typical neutrino emission within this population, leading to the limits: $E_{\rm tot, \nu} < 4.0 \times 10^{53}\,$erg and $f_\nu < 0.15$ (respectively, $E_{\rm tot, \nu} < 3.2 \times 10^{53}\,$erg and $f_\nu < 0.88$) for $E^{-2}$ spectrum and isotropic emission. Other assumptions including softer spectra and non-isotropic scenarios have also been tested.

Recently an improved value of neutron skin thickness of $^{208}\text{Pb}$ was reported in Lead Radius EXperiment-2 (PREX-2) to be $R_{\text{skin}}=R_n - R_p=(0.283\pm 0.071)$ fm which corresponds to high estimations of nuclear symmetry energy ($E_{\text{sym}}$) and its slope ($L_{\text{sym}}$). The updated values of $E_{\text{sym}}$ and $L_{\text{sym}}$ commensurating to the neutron star observable estimations lie exterior to the astrophysical observed range. The higher values of $L_{\text{sym}}$ at $n_0$ deduced from recent PREX-2 data correlates to matter being easily deformable (yielding higher radius values) around intermediate matter densities leading to higher values of $\tilde{\Lambda}$ creating a tension between the terrestrial and astrophysical observations. In this study, we exploit this tension to constrain the $\Delta$-scalar meson coupling parameter space.

We present JWST and Hubble Space Telescope (HST) observations of the afterglow of GRB\,221009A, the brightest gamma-ray burst (GRB) ever observed. Observations obtained with NIRSPEC (0.6-5.5 micron) and MIRI (5-12 micron) 12 days after the burst are the first mid-IR spectroscopy performed for a GRB. Assuming the underlying slope is that of a single power-law, we obtain $\beta \approx 0.35$ and $A_V = 4.9$, in excess of the notional Galactic value. This is suggestive of extinction above the notional Galactic value, possibly due to patchy extinction within the Milky Way or dust in the GRB host galaxy. It further implies that the X-ray and optical/IR regimes are not on the same branch of the synchrotron spectrum of the afterglow. If the cooling break lies between the X-ray and optical/IR, then the temporal declines would only match for a post jet break, ISM medium and electron index with $p<2$. The shape of the JWST spectrum is near-identical in the optical/nIR to X-shooter spectroscopy obtained at 0.5 days and to later time observations with HST. The lack of spectral evolution suggests the SNe is either substantially fainter or bluer than SN~1998bw. Our {\em HST} observations also reveal a disc-like host galaxy, viewed close to edge-on that further complicates the isolation of any supernova component. The host galaxy appears rather typical amongst long-GRB hosts and suggests that the extreme properties of GRB 221009A are not directly tied to its galaxy-scale environment.

The importance of the quiet-Sun magnetism is that it is always there to a greater or lesser extent, being a constant provider of energy, independently of the solar cycle phase. The open questions about the quiet-Sun magnetism include those related to its origin. Most people claim that the local dynamo action is the mechanism that causes it. This fact would imply that the quiet-Sun magnetism is nearly the same at any location over the solar surface and at any time. Many works claim that the quiet Sun does not have any variation at all, although a few of them raise doubt on this claim and find mild evidence of a cyclic variation in the the quiet-Sun magnetism. In this work, we detect clear variations in the internetwork magnetism both with latitude and solar cycle. In terms of latitude, we find an increase in the averaged magnetic fields toward the solar poles. We also find long-term variations in the averaged magnetic field at the disk center and solar poles, and both variations are almost anticorrelated. These findings do not support the idea that the local dynamo action is the unique factory of the quiet-Sun magnetism.

The presence of blue-cored dwarf early-type galaxies (dE(bc)s) in high-density environments supports the scenario of the transformation of infalling late-type galaxies into quiescent dwarf early-type galaxies by environmental effects. While low-density environments lacking environmental processes could not be relevant to the formation of dE(bc)s, we discovered a large sample of rare dE(bc)s in isolated environments at z < 0.01 using the NASA-Sloan Atlas catalog. Thirty-two isolated dE(bc)s were identified by visual inspection of the Sloan Digital Sky Survey images and g - r color profiles. We found that (1) isolated dE(bc)s exhibit similar structural parameters to dE(bc)s in the Virgo cluster; (2) based on the ultraviolet-r color-magnitude relation, color gradients, and optical emission lines of dE(bc)s, isolated dE(bc)s show more vigorous, centrally concentrated SF compared to their counterparts in the Virgo cluster; (3) at a given stellar mass, isolated dE(bc)s tend to have a larger fraction of gas mass than their Virgo counterparts. We discuss a scenario of episodic SF sustained by gas accretion, suggested by Sanchez Almeida et al., in which the star-bursting blue compact dwarf galaxy (BCD)-quiescent BCD (QBCD) cycle can be repeated during the Hubble time. We suggest that, in this cadence, isolated dE(bc)s might be QBCDs at pre- or post-BCD stages. Our results imply that dE(bc)s comprise a mixture of objects with two types of origins, nature or nurture, depending on their environment.

Asteroseismic measurements of the internal rotation rate in evolved stars pointed out to a lack of angular momentum (AM) transport in stellar evolution models. Several physical processes in addition to hydrodynamical ones were proposed as candidates for the missing mechanism. Nonetheless, no current candidate can satisfy all the constraints provided by asteroseismology. We revisit the role of a candidate process whose efficiency scales with the contrast between the rotation rate of the core and the surface which was proposed to be related to the azimuthal magneto-rotational instability (AMRI) by Spada et al. We compute stellar evolution models of low- and intermediate-mass stars with the parametric formulation of AM transport proposed by Spada et al. until the end of the core-helium burning for low- and intermediate-mass stars and compare our results to the latest asteroseismic constraints available in the post main sequence phase. Both hydrogen-shell burning stars in the red giant branch and core-helium burning stars of low- and intermediate-mass in the mass range $1 M_{\odot} \lesssim M \lesssim 2.5 M_{\odot}$ can be simultaneously reproduced by this kind of parametrisation. Given current constraints from asteroseismology, the core rotation rate of post-main sequence stars seems to be well explained by a process whose efficiency is regulated by the internal degree of differential rotation in radiative zones.

Gravitational instability plays a substantial role in the evolution of galaxies. Various schemes to include it in galaxy evolution models exist, generally assuming that the Toomre $Q$ parameter is self-regulated to $Q_\mathrm{crit}$, the critical $Q$ dividing stable from unstable conditions in a linear stability analysis. This assumption is in tension with observational estimates of $Q$ that find values far below any plausible value of $Q_\mathrm{crit}$. While the observations are subject to some uncertainty, this tension can more easily be relieved on the theoretical side by relaxing the common assumption that $Q\ge Q_\mathrm{crit}$. Based on observations of both $z\sim 2$ disks and local face-on galaxies, we estimate the effect of gravitational instability necessary to balance out every other physical process that affects $Q$. In particular we find that the disk's response to low $Q$ values can be described by simple functions that depend only on $Q$. These response functions allow galaxies to maintain $Q$ values below $Q_\mathrm{crit}$ in equilibrium over a wide range of parameters. Extremely low values of $Q$ are predicted when the gas surface density is greater than $\sim 10^3$ M$_\odot$ pc$^{-2}$, the rotation curve provides minimal shear, the orbital time becomes long, and/or when the gas is much more unstable than the stellar component. We suggest that these response functions should be used in place of the $Q\ge Q_\mathrm{crit}$ ansatz.

We reconstruct the star formation history of the Sco-Cen OB association using a novel high-resolution age map of the region. We develop an approach to produce robust ages for Sco-Cen's recently identified 37 stellar clusters using the \texttt{SigMA} algorithm. The Sco-Cen star formation timeline reveals four periods of enhanced star formation activity, or bursts, remarkably separated by about 5 Myr. Of these, the second burst, which occurred 15 million years ago, is by far the dominant, and most of Sco-Cen's stars and clusters were in place by the end of this burst. The formation of stars and clusters in Sco-Cen is correlated, but not linearly, meaning that more stars were formed per cluster during the peak of star formation rate. Most of the clusters, which are large enough to have supernova precursors, were formed during the 15 Myr period. Star and cluster formation activity has been continuously declining since then. We have clear evidence that Sco-Cen formed from the inside out and contains 100-pc long correlated chains of contiguous clusters exhibiting well-defined age gradients, from massive older clusters to smaller young clusters. These observables suggest an important role for feedback in the formation of about half of Sco-Cen stars, although follow-up work is needed to quantify this statement. Finally, we confirm that the Upper-Sco age controversy discussed in the literature during the last decades is solved: the region toward Upper-Sco, a benchmark region for planet formation studies, contains not one but up to nine clusters spanning ages from 3 to 19 Myr.

We present asevolution, a cosmological N-body code developed based on gevolution, which consistently solves for the (a)symmetron scalar field and metric potentials within the weak-field approximation. In asevolution, the scalar field is dynamic and can form non-linear structures. A cubic term is added in the symmetron potential to make the symmetry-broken vacuum expectation values different, which is motivated by observational tensions in the late-time universe. To study the effects of the scalar field dynamics, we also implement a constraint solver making use of the quasi-static approximation, and provide options for evaluating the background evolution, including using the full energy density averaged over the simulation box within the Friedmann equation. The asevolution code is validated by comparison with the Newtonian N-body code ISIS that makes use of the quasi-static approximation. There is found a very small effect of including relativistic and weak-field corrections in our small test simulations; it is seen that for small masses, the field is dynamic and can not be accurately solved for using the quasi-static approximation; and we observe the formation of unstable domain walls and demonstrate a useful way to identify them within the code. A first consideration indicates that the domain walls are more unstable in the asymmetron scenario.

While many Lyman-alpha Blobs (LABs) are found in and around several well-known protoclusters at high redshift, how they trace the underlying large-scale structure is still poorly understood. In this work, we utilize 5,352 Lyman-alpha emitters (LAEs) and 129 LABs at z=3.1 identified over a $\sim$ 9.5 sq. degree area in early data from the ongoing One-hundred-deg$^2$ DECam Imaging in Narrowbands (ODIN) survey to investigate this question. Using LAEs as tracers of the underlying matter distribution, we identify overdense structures as galaxy groups, protoclusters, and filaments of the cosmic web. We find that LABs preferentially reside in regions of higher-than-average density and are located in closer proximity to overdense structures, which represent the sites of protoclusters and their substructures. Moreover, protoclusters hosting one or more LABs tend to have a higher descendant mass than those which do not. Blobs are also strongly associated with filaments of the cosmic web, with $\sim$ 70% of the population being within a projected distance of 2.4 pMpc from a filament. We show that the proximity of LABs to protoclusters is naturally explained by their association with filaments as large cosmic structures are where many filaments converge. The contiguous wide-field coverage of the ODIN survey allows us for the first time to firmly establish a connection between LABs as a population and their environment.

Gravito-inertial asteroseismology saw its birth thanks to high-precision CoRoT and Kepler space photometric light curves. So far, it gave rise to the internal rotation frequency of a few hundred intermediate-mass stars, yet only several tens of these have been weighed, sized, and age-dated with high precision from asteroseismic modelling. We aim to increase the sample of optimal targets for future gravito-inertial asteroseismology by assessing the properties of 15062 newly found Gaia DR3 gravity-mode pulsators. We also wish to investigate if there is any connection between their fundamental parameters and dominant mode on the one hand, and their spectral line broadening measured by Gaia on the other hand. After re-classifying about 22% of the F-type gravity-mode pulsators as B-type according to their effective temperature, we construct histograms of the fundamental parameters and mode properties of the 15062 new Gaia DR3 pulsators. We compare these histograms with those of 63 Kepler bona fide class members. We fit errors-in-variables regression models to couple the effective temperature, luminosity, gravity, and oscillation properties to the two Gaia DR3 parameters capturing spectral line broadening for a fraction of the pulsators. We find that the selected 15062 gravity-mode pulsators have properties fully in line with those of their well-known Kepler analogues, revealing that Gaia has a role to play in asteroseismology. The dominant g-mode frequency is a significant predictor of the spectral line broadening for the class members having this quantity measured. We show that the Gaia vbroad parameter captures the joint effect of time-independent intrinsic and rotational line broadening and time-dependent tangential pulsational broadening. Gaia was not desiged to detect non-radial oscillations, yet its homogeneous data treatment allow us to identify many new gravity-mode pulsators.

Recently there are more and more interest on the gravitational wave of moving sources. This introduces a Lorentz transformation problem of gravitational wave. Although Bondi-Metzner-Sachs (BMS) theory has in principle already included the Lorentz transformation of gravitational wave, the transformation of the three dimensional gravitational wave tensor has not been explicitly calculated before. Within four dimensional spacetime, gravitational wave have property of `boost weight zero' and `spin weight 2'. This fact makes the Lorentz transformation of gravitational wave difficult to understand. In the current paper we adopt the traditional three dimensional tensor description of gravitational wave. Such a transverse-traceless tensor describes the gravitational wave freedom directly. We derive the explicit Lorentz transformation of the gravitational wave tensor. The transformation is similar to the Lorentz transformation for electric field vector and magnetic field vector which are three dimensional vectors. Based on the deduced Lorentz transformation of the gravitational wave three dimensional tensor, we can construct the gravitational waveform of moving source with any speed if only the waveform of the corresponding rest waveform is given. As an example, we apply our method to the effect of kick velocity of binary black hole. The adjusted waveform by the kick velocity is presented.

A large number of galactic binary systems emit gravitational waves (GW) continuously with frequencies below $\sim$10 mHz. The LISA mission could identify the tens of thousands of binaries over years of observation and will be subject to the confusion noise around 1 mHz yielded by the unresolved sources. Beyond LISA, there are several missions have been proposed to observe GWs in the sub-mHz range where the galactic foreground is expected to be overwhelming the instrumental noises. In this study, we investigate the detectability of sub-mHz GW missions to detect the galactic double white dwarf (DWD) binaries and evaluate the confusion noise produced by the undistinguished DWDs. This confusion noise could also be viewed as a stochastic GW foreground and be effectively observed in the sub-mHz band. The parameter determinations for the modeled foreground are examined by employing different detector sensitivities and population models. By assuming the determined foregrounds could be subtracted from the data, we evaluate the residuals which are expected to have power spectral densities two orders of magnitude lower than the originals data.

The Gravity Recovery And Climate Experiment - Follow On (GRACE-FO) satellite mission (2018-now) hosts the novel Laser Ranging Interferometer (LRI), a technology demonstrator for proving the feasibility of laser interferometry for inter-satellite ranging measurements. The GRACE-FO mission extends the valuable climate data record of changing mass distribution in the system Earth, which was started by the original GRACE mission (2002-2017). The mass distribution can be deduced from observing changes in the distance of two low-earth orbiters employing interferometry of electromagnetic waves in the K-Band for the conventional K-Band Ranging (KBR) and in near-infrared for the novel LRI. This paper identifies possible radiation-induced Single Event Upset (SEU) events in the LRI phase measurement. We simulate the phase data processing within the Laser Ranging Processor (LRP) and use a template-based fitting approach to determine the parameters of the SEU and subtract the events from the ranging data. Over four years of LRI data, 29 of such events were identified and characterized.

A new generation of terrestrial gravitational wave detectors is currently being planned for the next decade, and it is expected to detect most of the coalescences of compact objects in the universe with masses up to a thousand times the solar mass. Among the several possible applications of current and future detections, we focus on the impact on the measure of the luminosity distance of the sources, which is an invaluable tool for constraining the cosmic expansion history of the universe. Focusing on two specific detector topologies, triangular and L-shape, we investigate how topology and relative orientation of up to three detectors can minimise the uncertainty measure of the luminosity distance. While the precision in distance measurement is correlated with several geometric angles determining the source position and orientation, focusing on the bright standard siren case, we obtain analytic and numerical results for its uncertainty depending on type and number of detectors composing a network, and the inclination angle of the binary plane with respect to the wave propagation direction. We also analyse the best relative location and orientation of two third generation detectors to minimise luminosity distance uncertainty, showing that the inclination angle distribution plays an important role in precision recovery of luminosity distance, and that a suitably arranged network of detectors can reduce drastically the uncertainty measure, approaching the limit imposed by lensing effects intervening between source and detector.