25 pages, 20 figures, part 14 of the BeyondPlanck release. All BeyondPlanck products and software will be released publicly at this http URL Submitted to A&A
We present the intensity foreground algorithms and model employed within the BeyondPlanck analysis framework. The BeyondPlanck analysis includes a limited set of frequency channels, and it is therefore particularly sensitive to parameter degeneracies. We discuss various priors that are introduced to break these degeneracies, and we improve the previous $Planck$-based $\texttt{Commander}$ component separation implementation in four specific ways that are all designed to improve stability and computational efficiency for weakly constrained posterior distributions. These are 1) joint foreground spectral parameter and amplitude sampling, building on ideas from Miramare; 2) component-based monopole determination; 3) joint spectral parameter and monopole sampling; and 4) application of informative spatial priors for component amplitude maps. We find that the only spectral parameter with a significant signal-to-noise ratio using the current BeyondPlanck data set is the peak frequency of the anomalous microwave emission component, for which we find $\nu_{\mathrm{p}}=25.3\pm0.5$ GHz; all others must be constrained through external priors. Future work will aim at integrating many more data sets into this analysis, both map and time-ordered based, and thereby gradually eliminating the currently observed degeneracies in a controlled manner with respect to both instrumental systematic effects and astrophysical degeneracies. This work will be organized within the Open Science-based Cosmoglobe community effort.
Orbital characteristics based on Gaia Early Data Release 3 astrometric parameters are analyzed for ${\sim} 8,000$ metal-poor stars ([Fe/H] $\leq -0.8$) compiled from the RAdial Velocity Experiment (RAVE) Data Release 6. Selected as metal-poor candidates based on broadband photometry, RAVE collected moderate-resolution ($R \sim 7,500$) spectra in the region of the Ca triplet for these stars. About $20\%$ of the stars in this sample also have medium-resolution ($1,200 \lesssim R \lesssim 2,000$) validation spectra obtained over a four-year campaign from $2014$ to $2017$ with a variety of telescopes. We match the candidate stars to photometric metallicity determinations from the Huang et al. recalibration of the Sky Mapper Southern Survey Data Release 2. We obtain dynamical clusters of these stars from the orbital energy and cylindrical actions using the \HDBSCAN ~unsupervised learning algorithm. We identify $179$ Dynamically Tagged Groups (DTGs) with between $5$ and $35$ members; $67$ DTGs have at least $10$ member stars. Milky Way (MW) substructures such as Gaia-Sausage-Enceladus, the Metal-Weak Thick Disk, the Splashed Disk, Thamnos, the Helmi Stream, and LMS-1 (Wukong) are identified. Associations with MW globular clusters are determined for $10$ DTGs; no recognized MW dwarf galaxies were associated with any of our DTGs. Previously identified dynamical groups are also associated with our DTGs, with emphasis placed on their structural determination and possible new identifications. We identify chemically peculiar stars as members of several DTGs; we find $22$ DTGs that are associated with \textit{r}-process-enhanced stars. Carbon-enhanced metal-poor (CEMP) stars are identified among the targets with available spectroscopy, and we assign these to morphological groups following the approach given by Yoon et al.
41 pages, 16 figures, accepted for publication in A&A
We know little about the outermost exoplanets in planetary systems, because our detection methods are insensitive to moderate-mass planets on wide orbits. However, debris discs can probe the outer-planet population, because dynamical modelling of observed discs can reveal properties of perturbing planets. We use four sculpting and stirring arguments to infer planet properties in 178 debris-disc systems from the ISPY, LEECH and LIStEN planet-hunting surveys. Similar analyses are often conducted for individual discs, but we consider a large sample in a consistent manner. We aim to predict the population of wide-separation planets, gain insight into the formation and evolution histories of planetary systems, and determine the feasibility of detecting these planets in the near future. We show that a `typical' cold debris disc likely requires a Neptune- to Saturn-mass planet at 10-100 au, with some needing Jupiter-mass perturbers. Our predicted planets are currently undetectable, but modest detection-limit improvements (e.g. from JWST) should reveal many such perturbers. We find that planets thought to be perturbing debris discs at late times are similar to those inferred to be forming in protoplanetary discs, so these could be the same population if newly formed planets do not migrate as far as currently thought. Alternatively, young planets could rapidly sculpt debris before migrating inwards, meaning that the responsible planets are more massive (and located further inwards) than debris-disc studies assume. We combine self-stirring and size-distribution modelling to show that many debris discs cannot be self-stirred without having unreasonably high masses; planet- or companion-stirring may therefore be the dominant mechanism in many (perhaps all) debris discs. Finally, we provide catalogues of planet predictions, and identify promising targets for future planet searches.
19 pages, 9 figures, 3 tables. Submitted to AJ
After observing WASP-12 in the second year of the primary mission, the Transiting Exoplanet Survey Satellite (TESS) revisited the system in late 2021 during its extended mission. In this paper, we incorporate the new TESS photometry into a reanalysis of the transits, secondary eclipses, and phase curve. We also present a new $K_s$-band occultation observation of WASP-12b obtained with the Palomar/WIRC instrument. The latest TESS photometry span three consecutive months, quadrupling the total length of the TESS WASP-12 light curve and extending the overall time baseline by almost two years. Based on the full set of available transit and occultation timings, we find that the orbital period is shrinking at a rate of $-29.81 \pm 0.94$ ms yr$^{-1}$. The additional data also increase the measurement precision of the transit depth, orbital parameters, and phase-curve amplitudes. We obtain a secondary eclipse depth of $466 \pm 35$ ppm, a $2\sigma$ upper limit on the nightside brightness of 70 ppm, and a marginal $6\overset{\circ}{.}2 \pm 2\overset{\circ}{.}8$ eastward offset between the dayside hotspot and the substellar point. The voluminous TESS dataset allows us to assess the level of atmospheric variability on timescales of days, months, and years. We do not detect any statistically significant modulations in the secondary eclipse depth or day-night brightness contrast. Likewise, our measured $K_s$-band occultation depth of $2810 \pm 390$ ppm is consistent with most $\sim$2.2 $\mu$m observations in the literature.
14 pages, 14 figures, submitted to MNRAS
Gradients in the stellar populations of galaxies -- e.g., in age, metallicity, IMF -- can result in gradients in the stellar mass to light ratio, $M_*/L$. Such gradients imply that the distribution of the stellar mass and light are different. For old stellar populations, such as those typical of early-type galaxies at $z\sim 0$, the $M_*/L$ gradients are weak if driven by variations in age and metallicity. However, if they are driven by variations in the stellar Initial Mass Function (IMF), then they can be significantly larger. An IMF-driven gradient which has $M_*/L$ decreasing outwards from the center increases the estimated total stellar mass ($M_*$) and reduces the scale which contains half this mass ($R_{e,*}$), compared to the values of mass and size when the gradient is ignored. We estimate IMF-gradients from spatially resolved spectra of early-type galaxies in the final release of the MaNGA survey, showing that the fractional decrease in $R_{e,*}$ can be significantly larger than the fractional $M_*$ increase, especially when the light is more centrally concentrated. The $R_{e,*}-M_*$ correlation which results from the IMF-driven $M_*/L$ gradients at $z\sim 0$ is offset by almost 0.3 dex to smaller sizes compared to when these gradients are ignored. Comparison with higher redshift samples is not straightforward. If it is fair to compare $z\sim 0$ `early-type' galaxies with `quiescent' galaxies at higher-$z$, then one must be able to consistently account for evolution in stellar population gradients (especially age and IMF) as well as changes in the steepness of the light profile before drawing conclusions about the evolution of the $R_{e,*}-M_*$ relation.
submitted to ApJ
Accepted for publication in The Astrophysical Journal
19 pages, 6 figures, 4 tables, accepted for publication in MNRAS
16 pages, 11 Figures, MNRAS Submitted
Accepted to A&A; 40 pages; 20 figures
21 pages, 8 figures
20 pages, 20 figures, submitted to MNRAS
16 pages, 8 figures
To appear in the Astronomical Journal
14 pages, 2 tables, 5 figures. Accepted for publication in ApJ Letters
8 pages and 10 figures
7 Pages, 9 Figures. Accepted for Publication in Astron. /& Astrophys 10 January 2022
38 pages, and 16 figures. Resubmitted to A&A after referee report
12 pages, 8 figures, submitted to Journal of Glaciology
26 pages, 14 figures, 8 tables, accepted to MNRAS
40 pages, 31 figures, 2 tables. Submitted to ApJ
9 pages, 2 figures
Accepted by PASP
17 pages, 12 figures, submitted to MNRAS
10 pages,6 figures, published by RAA, comments welcomed
11 pages, 7 figures, 1 table, accepted by A&A
12 pages, including 4 figures and 4 tables, accepted for publication in JKAS
11 pages, 5 figures, 1 table
This is a pre-copyedited, author-produced PDF of an article accepted for publication in Monthly Notices of the Royal Astronomical Society (MNRAS) following peer review
combined main test + supplement of published article
Accepted for publication in the SPIE Journal of Astronomical Telescopes, Instruments, and Systems (JATIS); 29 pages, 17 figures, 4 tables, quite a lot of stress, infinite patience. this http URL , this https URL
Accepted for publication in The Astrophysical Journal
Accepted for publication as a letter in A&A
9 pages, 4 Figures, 1 table. Accepted for Publication in ApJ Letters
18 pages, 10 figures
Submitted to MNRAS on January 19th
accepted for publication in A&A, 5 pages, including 5 figures, plus 2 pages appendix, including 2 figures
Accepted for Special Issue of Journal of Astrophysics and Astronomy, 2022, Astrophysical jets and observational facilities: National perspective, 05-09 April 2021, ARIES Nainital
12 pages, 10 figures
27 pages, 15 figures, 4 tables, submitted to AAS journals (12/10/2021), microlensing catalogs available at this https URL
18 Pages, 6 Figures, Symmetry MDPI, Review Paper
24 pages, 23 figures; Accepted to AJ
13 pages, 5 figures, 5 tables, accepted for publication in MNRAS
In review at ApJ. Comments & feedback welcome. Code available by request via GitHub
23 pages, 12 figures, Accepted to ApJ
8 pages, 1 figure, 1 table. Accepted for publication in MNRAS
25 pages, 17 figures, accepted for publication in A&A
6 pages, 5 figures
To be published, Nucl. Instrum. Meth. in Phys. Research A (2022)
8 pages, 5 figures; accepted by the Astrophysical Journal for publication
2 pages (The authors of the idea and translation are Bohdan Novosyadlyj and Roman Plyatsko.)
17 pages, 12 figures, 1 table. Physical Review E, in press
9 pages, 8 figures, 2 tables
25 pages, 24 figures
6 pages, 2 figures
13 pages, 9 figures, 2 tables