- ID:
- ivo://CDS.VizieR/J/AJ/157/109
- Title:
- Stellar proper motions in the Orion Nebula Cluster
- Short Name:
- J/AJ/157/109
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Orion Nebula Cluster (ONC) is the nearest site of ongoing massive star formation, which allows us to study the kinematics and dynamics of the region in detail and constrain star formation theories. Using HST ACS/WFPC2/WFC3IR and Keck II NIRC2 data, we have measured the proper motions of 701 stars within an ~6'x6' field of view around the center of the ONC. We have found more than 10 escaping star candidates, concentrated predominantly at the core of the cluster. The proper motions of the bound stars are consistent with a normal distribution, albeit elongated north-south along the Orion filament, with proper-motion dispersions of ({sigma}_{mu},{alpha}_*, {sigma}_{mu},{delta}_)=(0.83+/-0.02, 1.12+/-0.03) mas/yr or intrinsic velocity dispersions of ({sigma}_v,{alpha}_*, {sigma}_v,{delta}_)=(1.57+/-0.04, 2.12+/-0.06) km/s assuming a distance of 400 pc to the ONC. The cluster shows no evidence for tangential-to-radial anisotropy. Our velocity dispersion profile agrees with the prediction from the observed stellar + gas density profile from Da Rio et al. (2014ApJ...795...55D, 2017ApJ...845..105D), indicating that the ONC is in virial equilibrium. This finding suggests that the cluster was formed with a low star formation efficiency per dynamical timescale based on comparisons with current star formation theories. Our survey also recovered high-velocity IR sources BN, x and n in the BN/KL region. The estimated location of the first two sources ~500 yr ago agrees with that of the radio source I, consistent with their proposed common origin from a multistellar disintegration. However, source n appears to have a small proper motion and is unlikely to have been involved in the event.
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- ID:
- ivo://CDS.VizieR/J/ApJ/757/22
- Title:
- Strong and weak lensing analysis of A2261
- Short Name:
- J/ApJ/757/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We precisely constrain the inner mass profile of A2261 (z=0.225) for the first time and determine that this cluster is not "overconcentrated" as found previously, implying a formation time in agreement with {Lambda}CDM expectations. These results are based on multiple strong-lensing analyses of new 16-band Hubble Space Telescope imaging obtained as part of the Cluster Lensing and Supernova survey with Hubble (CLASH; Postman et al. 2012, Cat. J/ApJS/199/25). Combining this with revised weak-lensing analyses of Subaru wide-field imaging with five-band Subaru + KPNO photometry, we place tight new constraints on the halo virial mass M_vir_=(2.2+/-0.2)x10^15^M_{sun}_h^-1^_70_ (within r_vir_{approx}3Mpc.h^-1^_70_) and concentration c_vir_=6.2+/-0.3 when assuming a spherical halo. This agrees broadly with average c(M, z) predictions from recent {Lambda}CDM simulations, which span 5<~<c><~8. Our most significant systematic uncertainty is halo elongation along the line of sight (LOS). To estimate this, we also derive a mass profile based on archival Chandra X-ray observations and find it to be ~35% lower than our lensing-derived profile at r_2500_~600kpc. Agreement can be achieved by a halo elongated with a ~2:1 axis ratio along our LOS. For this elongated halo model, we find M_vir_=(1.7+/-0.2)x10^15^M_{sun}_h^-1^_70_ and c_vir_=4.6+/-0.2, placing rough lower limits on these values. The need for halo elongation can be partially obviated by non-thermal pressure support and, perhaps entirely, by systematic errors in the X-ray mass measurements. We estimate the effect of background structures based on MMT/Hectospec spectroscopic redshifts and find that these tend to lower M_vir_ further by ~7% and increase c_vir_by ~5%.
- ID:
- ivo://CDS.VizieR/J/ApJ/819/114
- Title:
- Strong lensing mass modeling of 4 HFF clusters
- Short Name:
- J/ApJ/819/114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We conduct precise strong lensing mass modeling of four Hubble Frontier Field (HFF) clusters, Abell 2744, MACS J0416.1-2403, MACS J0717.5+3745, and MACS J1149.6+2223, for which HFF imaging observations are completed. We construct a refined sample of more than 100 multiple images for each cluster by taking advantage of the full-depth HFF images, and conduct mass modeling using the glafic software, which assumes simply parametrized mass distributions. Our mass modeling also exploits a magnification constraint from the lensed SN Ia HFF14Tom for Abell 2744 and positional constraints from the multiple images S1-S4 of the lensed supernova SN Refsdal for MACS J1149.6+2223. We find that our best-fitting mass models reproduce the observed image positions with rms errors of ~0.4", which are smaller than rms errors in previous mass modeling that adopted similar numbers of multiple images. Our model predicts a new image of SN Refsdal with a relative time delay and magnification that are fully consistent with a recent detection of reappearance. We then construct catalogs of z~6-9 dropout galaxies behind the four clusters and estimate magnification factors for these dropout galaxies with our best-fitting mass models. The dropout sample from the four cluster fields contains ~120 galaxies at z>~6, about 20 of which are predicted to be magnified by a factor of more than 10. Some of the high-redshift galaxies detected in the HFF have lensing-corrected magnitudes of M_UV_~-15 to -14. Our analysis demonstrates that the HFF data indeed offer an ideal opportunity to study faint high-redshift galaxies. All lensing maps produced from our mass modeling will be made available on the Space Telescope Science Institute website (https://archive.stsci.edu/prepds/frontier/lensmodels/).
- ID:
- ivo://CDS.VizieR/J/ApJS/253/4
- Title:
- SuperBoRG: search HST parallel imaging data
- Short Name:
- J/ApJS/253/4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Hubble Space Telescope (HST) has been providing tremendous survey efficiency via its pure-parallel mode by observing another field in parallel with the primary instrument in operation for the primary observation. In this study, we present a new archival project, SuperBoRG, which aims at compiling data taken in extragalactic parallel programs of HST with the Wide Field Camera 3 in the past decade, including pure-parallel (BoRG, HIPPIES, and COS-GTO) and coordinated-parallel (CLASH and RELICS) programs. The total effective area reaches ~0.41deg^2^ from 4.1Ms, or 47days, of observing time, which is the largest collection of optical-to-near-infrared imaging data of HST for extragalactic science. We reduce all data in a consistent manner with an updated version of our data reduction pipeline, including a new sky background subtraction step. When available, imaging data from the Spitzer Space Telescope are also included in photometric analyses. The data set consists of 316 independent sight lines and is highly effective for identification of high-z luminous sources (M_UV_<~-20mag) at z~7-12, helping to minimize the effects of cosmic variance. As a demonstration, we present three new z>~7 source candidates, including one luminous galaxy candidate at z_phot_~10.4 with M_UV_~-21.9mag; the best-fit spectral energy distribution implies a large amount of stellar mass (logM_*_/M_{sun}_~10) and moderate dust attenuation (A_V_~1.4mag), though the possibility of it being a low-z interloper cannot be completely rejected (~23%) with the current data set. The data set presented in this study is also suited for intermediate- and low-z science cases.
- ID:
- ivo://CDS.VizieR/J/MNRAS/443/1821
- Title:
- Supersoft X-ray sources in M31
- Short Name:
- J/MNRAS/443/1821
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We searched for the optical/UV/IR counterparts of seven supersoft X-ray sources (SSSs) in M31 in the Hubble Space Telescope} (HST}) 'Panchromatic Hubble Andromeda Treasury' (PHAT) archival images and photometric catalogue. Three of the SSSs were transient; the other four are persistent sources. The PHAT offers the opportunity to identify SSSs hosting very massive white dwarfs (WDs) that may explode as Type Ia supernovae in single degenerate binaries, with magnitudes and colour indexes typical of symbiotics, high-mass close binaries, or systems with an optically luminous accretion disc. We find evidence that the transient SSSs were classical or recurrent novae; two probable counterparts that we identified are probably symbiotic binaries undergoing mass transfer at a very high rate. There is a candidate accreting WD binary in the error circle of one of the persistent sources, r3-8. In the spatial error circle of the best-studied SSS in M31, r2-12, no red giants or AGB stars are sufficiently luminous in the optical and UV bands to be symbiotic systems hosting an accreting and hydrogen-burning WD. This SSS has a known modulation of the X-ray flux with a 217.7s period, and we measured an upper limit on its derivative, namely |dP/dt|<~0.82x10^11. This limit can be reconciled with the rotation period of a WD accreting at a high rate in a binary with an orbital period of a few hours. However, there is no luminous counterpart with colour indexes typical of an accretion disc irradiated by a hot central source. Adopting a semi-empirical relationship, the upper limit for the disc optical luminosity implies an upper limit of only 169-min for the orbital period of the WD binary.
- ID:
- ivo://CDS.VizieR/J/ApJ/749/121
- Title:
- Surface brightness profiles of z=2 galaxies
- Short Name:
- J/ApJ/749/121
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use deep Hubble Space Telescope Wide Field Camera 3 near-infrared imaging obtained of the GOODS-South field as part of the CANDELS survey to investigate a stellar mass-limited sample of quiescent galaxies at 1.5<z<2.5. We measure surface brightness profiles for these galaxies using a method that properly measures low surface brightness flux at large radii. We find that quiescent galaxies at z~2 very closely follow Sersic profiles, with n_median_=3.7, and have no excess flux at large radii. Their effective radii are a factor of ~4 smaller than those of low-redshift quiescent galaxies of similar mass. However, there is a significant spread in sizes ({sigma}_log_10_r_e__=0.24), with the largest z~2 galaxies lying close to the z=0 mass-size relation. We compare the stellar mass surface density profiles with those of massive elliptical galaxies in the Virgo Cluster and confirm that most of the mass growth which occurs between z~2 and z=0 must be due to accretion of material onto the outer regions of the galaxies. Additionally, we investigate the evolution in the size distribution of massive quiescent galaxies. We find that the minimum size growth required for z~2 quiescent galaxies to fall within the z=0 size distribution is a factor of ~2 smaller than the total median size growth between z~2 and z=0.
- ID:
- ivo://CDS.VizieR/J/ApJ/845/146
- Title:
- The Carnegie-Chicago Hubble Program. II. IC 1613
- Short Name:
- J/ApJ/845/146
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- IC 1613 is an isolated dwarf galaxy within the Local Group. Low foreground and internal extinction, low metallicity, and low crowding make it an invaluable testbed for the calibration of the local distance ladder. We present new, high-fidelity distance estimates to IC 1613 via its Tip of the Red Giant Branch (TRGB) and its RR Lyrae (RRL) variables as part of the Carnegie-Chicago Hubble Program, which seeks an alternate local route to H_0_ using Population II stars. We have measured a TRGB magnitude I_ACS_^TRGB^=20.35+/-0.01_stat_+/-0.01_sys_mag using wide-field observations obtained from the IMACS camera on the Magellan-Baade telescope. We have further constructed optical and near-infrared RRL light curves using archival BI- and new H-band observations from the ACS/WFC and WFC3/IR instruments on board the Hubble Space Telescope (HST). In advance of future Gaia data releases, we set provisional values for the TRGB luminosity via the Large Magellanic Cloud and Galactic RRL zero-points via HST parallaxes. We find corresponding true distance moduli {mu}_0_^TRGB^=24.30+/-0.03_stat_+/-0.05_sys_mag and <{mu}_0_^RRL^>=24.28+/-0.04_stat+sys_mag. We compare our results to a body of recent publications on IC 1613 and find no statistically significant difference between the distances derived from Population I and II stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/746/85
- Title:
- THe HST Cluster Supernova Survey. V.
- Short Name:
- J/ApJ/746/85
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Advanced Camera for Surveys, NICMOS, and Keck adaptive-optics-assisted photometry of 20 Type Ia supernovae (SNe Ia) from the Hubble Space Telescope (HST) Cluster Supernova Survey. The SNe Ia were discovered over the redshift interval 0.623<z<1.415. Of these SNe Ia, 14 pass our strict selection cuts and are used in combination with the world's sample of SNe Ia to derive the best current constraints on dark energy. Of our new SNe Ia, 10 are beyond redshift z = 1, thereby nearly doubling the statistical weight of HST-discovered SNe Ia beyond this redshift. Our detailed analysis corrects for the recently identified correlation between SN Ia luminosity and host galaxy mass and corrects the NICMOS zero point at the count rates appropriate for very distant SNe Ia. Adding these SNe improves the best combined constraint on dark-energy density, {rho}_DE_(z), at redshifts 1.0<z<1.6 by 18% (including systematic errors).
- ID:
- ivo://CDS.VizieR/J/A+A/647/A89
- Title:
- The OTELO survey as morphological probe
- Short Name:
- J/A+A/647/A89
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The morphology of galaxies provide us with a unique tool to connect and understand other related physical properties and their changes over the course of cosmic time. Only recently, thanks to big and/or deep surveys, we have access to a wealth of data for unprecedented number galaxies. The morphological catalogue of the OTELO survey galaxies detected in Hubble Space Telescope (HST)-ACS F814W images is presented. We explore various methods from previous works to separate early-type (ET) and late-type (LT) galaxies classified via spectral energy distribution (SED) fittings using galaxy templates. Together with this article we release the catalogue containing main morphological parameters in F606W and F814W bands derived for more than 8000 sources. The morphological analysis is based on the single-Sersic profile fit. The GALAPAGOS-2 software was used in order to provide multi-wavelength morphological parameters fitted simultaneously in two HST-ACS bands. GALAPAGOS-2 detects, prepares guess values for GALFIT-M, and provides the best-fitting single-Sersic model in both bands for each source. Stellar masses were estimated using synthetic rest-frame magnitudes recovered from SED-fitting of galaxy templates. The morphological catalogue is complemented with concentration indexes from a separate SExtractor dual, high dynamical range mode. A total of 8812 sources were successfully fitted with single-Sersic profiles. The analysis of a carefully selected sample of ~3000 sources up to z_phot=2 is presented in this work, from which 873 sources were not detected in previous studies. We found no statistical evidence for the evolution of low-mass end of mass-size relation for ET and LT since z=2. Furthermore, we found a good agreement on the median size evolution for ET and LT galaxies, for a given stellar-mass, with data in the literature. Compared to previous works on faint field galaxies, we found similarities regarding rest-frame colours, Sersic and concentration indices.
- ID:
- ivo://CDS.VizieR/J/ApJ/705/1099
- Title:
- The Sloan Lens ACS (SLACS) Survey. IX.
- Short Name:
- J/ApJ/705/1099
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the current photometric data set for the Sloan Lens ACS (SLACS) Survey, including Hubble Space Telescope (HST) photometry from Advanced Camera for Surveys, WFPC2, and NICMOS. These data have enabled the confirmation of an additional 15 grade "A" (certain) lens systems, bringing the number of SLACS grade "A" lenses to 85; including 13 grade "B" (likely) systems, SLACS has identified nearly 100 lenses and lens candidates. Approximately 80% of the grade "A" systems have elliptical morphologies while ~10% show spiral structure; the remaining lenses have lenticular morphologies. Spectroscopic redshifts for the lens and source are available for every system, making SLACS the largest homogeneous data set of galaxy-scale lenses to date. The ensemble properties of the SLACS lens galaxies, e.g., stellar masses and projected ellipticities, appear to be indistinguishable from other SDSS galaxies with similar stellar velocity dispersions. This further supports that SLACS lenses are representative of the overall population of massive early-type galaxies with M_*_>~10^11^M_{sun}_, and are therefore an ideal data set to investigate the kpc-scale distribution of luminous and dark matter in galaxies out to z~0.5.
