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- ID:
- ivo://CDS.VizieR/J/ApJ/822/78
- Title:
- VLT/MUSE spectroscopic obs. of MACS J1149.5+2223
- Short Name:
- J/ApJ/822/78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Multi Unit Spectroscopic Explorer (MUSE) observations in the core of the Hubble Frontier Fields (HFF) galaxy cluster MACSJ1149.5+2223, where the first magnified and spatially resolved multiple images of supernova (SN) "Refsdal" at redshift 1.489 were detected. Thanks to a Director's Discretionary Time program with the Very Large Telescope and the extraordinary efficiency of MUSE, we measure 117 secure redshifts with just 4.8hr of total integration time on a single 1arcmin^2^ target pointing. We spectroscopically confirm 68 galaxy cluster members, with redshift values ranging from 0.5272 to 0.5660, and 18 multiple images belonging to seven background, lensed sources distributed in redshifts between 1.240 and 3.703. Starting from the combination of our catalog with those obtained from extensive spectroscopic and photometric campaigns using the Hubble Space Telescope (HST), we select a sample of 300 (164 spectroscopic and 136 photometric) cluster members, within approximately 500kpc from the brightest cluster galaxy, and a set of 88 reliable multiple images associated with 10 different background source galaxies and 18 distinct knots in the spiral galaxy hosting SN "Refsdal". We exploit this valuable information to build six detailed strong-lensing models, the best of which reproduces the observed positions of the multiple images with an rms offset of only 0.26". We use these models to quantify the statistical and systematic errors on the predicted values of magnification and time delay of the next emerging image of SN "Refsdal". We find that its peak luminosity should occur between 2016 March and June and should be approximately 20% fainter than the dimmest (S4) of the previously detected images but above the detection limit of the planned HST/WFC3 follow-up. We present our two-dimensional reconstruction of the cluster mass density distribution and of the SN "Refsdal" host galaxy surface brightness distribution. We outline the road map toward even better strong-lensing models with a synergetic MUSE and HST effort.
- ID:
- ivo://CDS.VizieR/J/A+A/512/A12
- Title:
- VLT/VIMOS spectroscopy in GOODS-South field
- Short Name:
- J/A+A/512/A12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the full data set of the VIsible Multi-Object Spectrograph (VIMOS) spectroscopic campaign of the ESO/GOODS program in the Chandra Deep Field South (CDFS), which complements the FORS2 ESO/GOODS spectroscopic campaign. The ESO/GOODS spectroscopic programs are aimed at reaching signal-to-noise ratios adequate to measure redshifts for galaxies with AB magnitudes in the range ~24-25 in the B and R band using VIMOS, and in the z band using FORS2.
- ID:
- ivo://CDS.VizieR/J/ApJ/889/148
- Title:
- V346 Nor IJHKs photometry & IR spectra
- Short Name:
- J/ApJ/889/148
- Date:
- 17 Jan 2022 11:51:03
- Publisher:
- CDS
- Description:
- FU Orionis-type objects (FUors) are young low-mass stars undergoing powerful accretion outbursts. The increased accretion is often accompanied by collimated jets and energetic, large-scale molecular outflows. The extra heating during the outburst may also induce detectable geometrical, chemical, and mineralogical changes in the circumstellar material, affecting possible planet formation around these objects. V346 Nor is a southern FUor with peculiar spectral characteristics. Decades after the beginning of its outburst, it unexpectedly underwent a fading event around 2010 due to a decrease in the mass accretion rate onto the star by at least two orders of magnitude. Here we present optical and near-infrared photometry and spectroscopy obtained after the minimum. Our light curves show a gradual re-brightening of V346 Nor, with its Ks-band brightness only 1.5mag below the outburst brightness level. Our Very Large Telescope (VLT)/XSHOOTER spectroscopic observations display several strong forbidden emission lines toward the source from various metals and molecular hydrogen, suggesting the launch of a new jet. Our N-band spectrum obtained with VLT/VISIR outlines a deeper silicate absorption feature than before, indicating that the geometry of the circumstellar medium has changed in the post-outburst period compared to peak brightness.
- ID:
- ivo://CDS.VizieR/J/A+A/644/A135
- Title:
- V646 Pup TESS and ground photometry and spectrum
- Short Name:
- J/A+A/644/A135
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We investigate small-scale light variations in V646 Pup occurring in the timescales of days, weeks and years. To check if this variability is similar to that observed in FU Ori. We observed V646 Pup on six occasions at the SAAO and CTIO during 2013-2018 in Johnson and Sloan filters, typically with 1 d cadence maintained for 2-4 weeks. We also utilise the public-domain 1512 day long ASAS-SN light curve and TESS photometry obtained in 2019 during 24.1 days with 30 min cadence. New SAAO low-resolution spectra help to update major disc parameters, while the archival high-resolution Keck spectra are used to search for temporal changes in the disc rotational profiles. The ground-based observations confirm the constantly decreasing brightness of V646 Pup at the rate of 0.018mag per year. Precise i-band sensitive TESS data show that the little 0.005-0.01mag light variations imposed on this general trend do consist of a few independent wave trains of apparently time-coherent nature. Assuming that this is typical situation, from analysis of colour-magnitude diagrams obtained on earlier epochs we preliminarily inferred that the bulk of observed light changes could be owing to rotation of disc photosphere inhomogeneities, arising between 10-12 solar radii from the star. It is not excluded that these inhomogeneities could also manifest themselves in rotational profiles of the disc, as obtained from the high-resolution spectra. Assuming Keplerian rotation of these inhomogeneities, we preliminarily determine the stellar mass at 0.7-0.9 solar masses. At least during certain weeks V646 Pup shows time-coherent light variability pattern(s) that could be explained by rotation of an inhomogeneous disc photosphere. These preliminary results are similar to those better established for FU Ori, what suggests a common driving mechanism(s).
- ID:
- ivo://CDS.VizieR/J/MNRAS/482/301
- Title:
- WASP-147b, 160Bb, 164b, and 165b phot. and RV
- Short Name:
- J/MNRAS/482/301
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the discovery of four transiting hot Jupiters, WASP-147, WASP-160B, WASP-164, and WASP-165 from the WASP survey. WASP-147b is a near Saturn-mass (Mp=0.28M_J_) object with a radius of 1.11R_J_ orbiting a G4 star with a period (of 4.6d. WASP-160Bb has a mass and radius (Mp=0.28M_J_, Rp=1.09R_J_) (near-identical to WASP-147b, but is less irradiated, orbiting a metal-rich ([Fe/H]*=0.27) K0 star with a period of 3.8d. WASP-160B is part of a near equal-mass visual binary with an on-sky separation of 28.5 arcsec. WASP-164b is a more massive (Mp=2.13M_J_, Rp=1.13R_J_) hot Jupiter, orbiting a G2 star on a close-in (P=1.8d), but tidally stable orbit. WASP-165b is a classical (Mp=0.66M_J_, Rp=1.26R_J_) hot Jupiter in a 3.5d period orbit around a metal-rich ([Fe/H]*=0.33) star. WASP-147b and WASP-160Bb are promising targets for atmospheric characterization through transmission spectroscopy, while WASP-164b presents a good target for emission spectroscopy.
- ID:
- ivo://CDS.VizieR/J/MNRAS/448/2260
- Title:
- White dwarf candidates in SDSS DR10
- Short Name:
- J/MNRAS/448/2260
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a method which uses cuts in colour-colour and reduced proper motion-colour space to select white dwarfs without the recourse to spectroscopy while allowing an adjustable compromise between completeness and efficiency. Rather than just producing a list of white dwarf candidates, our method calculates a probability of being a white dwarf (P_WD_) for any object with available multiband photometry and proper motion. We applied this method to all objects in the Sloan Digital Sky Survey (SDSS) Data Release 10 (DR10) photometric footprint and to a few selected sources in DR7 which did not have reliable photometry in DR9 or DR10. This application results in a sample of 61 969 DR10 and 3799 DR7 photometric sources with calculated P_WD_ from which it is possible to select a sample of ~23000 high-fidelity white dwarf candidates with T_eff_>~7000K and g<=19. This sample contains over 14000 high confidence white dwarfs candidates which have not yet received spectroscopic follow-up. These numbers show that, to date, the spectroscopic coverage of white dwarfs in the SDSS photometric footprint is, on average, only ~40 percent complete. While we describe here in detail the application of our selection to the SDSS catalogue, the same method could easily be applied to other multicolour, large area surveys. We also publish a list of 8701 bright (g<=19) white dwarfs with SDSS spectroscopy, of which 1781 are new identifications in DR9/DR10.
- ID:
- ivo://CDS.VizieR/J/ApJ/867/62
- Title:
- White dwarf population of Messier 67
- Short Name:
- J/ApJ/867/62
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- White dwarfs (WDs) are excellent forensic tools for studying end-of-life issues surrounding low- and intermediate-mass stars, and the old, solar metallicity open star cluster Messier 67 is a proven laboratory for the study of stellar evolution for solar-type stars. In this paper, we present a detailed spectroscopic study of brighter (M_g_<=12.4) WDs in Messier 67, and in combination with previously published proper motion membership determinations, we identify a clean, representative sample of cluster WDs, including 13 members with hydrogen-dominated atmospheres, at least one of which is a candidate double degenerate, and 5 members with helium-dominated atmospheres. Using this sample we test multiple predictions surrounding the final stages of stellar evolution in solar-type stars. In particular, the stochasticity of the integrated mass lost by ~1.5 solar mass stars is less than 7% of the WD remnant mass. We identify WDs likely resulting from binary evolution, including at least one blue straggler remnant and two helium-core WDs. We observe no evidence of a significant population of helium-core WDs formed by enhanced mass loss on the red giant branch of the cluster. The distribution of WD atmospheric compositions is fully consistent with that in the field, limiting proposed mechanisms for the suppression of helium atmosphere WD formation in star clusters. In short, the WD population of Messier 67 is fully consistent with basic predictions of single- and multiple-star stellar evolution theories for solar metallicity stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/866/44
- Title:
- WISE/DEIMOS Redshift Catalog DR2 & extended data
- Short Name:
- J/ApJ/866/44
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The WISE satellite surveyed the entire sky multiple times in four infrared (IR) wavelengths (3.4, 4.6, 12, and 22{mu}m). This all-sky IR photometric survey makes it possible to leverage many of the large publicly available spectroscopic redshift surveys to measure galaxy properties in the IR. While characterizing the cross-matching of WISE data to a single survey is a straightforward process, doing it with six different redshift surveys takes a fair amount of space to characterize adequately, because each survey has unique caveats and characteristics that need addressing. This work describes a data set that results from matching five public redshift surveys with the AllWISE data release, along with a reanalysis of the data described in Lake+ (2012, J/AJ/143/7). The combined data set has an additional flux limit of 80{mu}Jy (19.14 AB mag) in WISE's W1 filter, imposed in order to limit it to targets with high completeness and reliable photometry in the AllWISE data set. Consistent analysis of all of the data is only possible if the color bias discussed in Ilbert+ (2004MNRAS.351..541I) is addressed (e.g., the techniques explored in Lake+ 2017AJ....153..189L). The sample defined herein is used in a companion paper in this series to measure the luminosity function of galaxies at 2.4{mu}m rest-frame wavelength, and the selection process of the sample is optimized for this purpose.
- ID:
- ivo://CDS.VizieR/J/A+A/624/A63
- Title:
- W51 OB stars NIR spectroscopy
- Short Name:
- J/A+A/624/A63
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The interplay between the formation of stars, stellar feedback and cloud properties strongly influences the star formation history of giant molecular clouds. The formation of massive stars leads to a variety of stellar clusters, ranging from low stellar density OB associations to dense, gravitationally bound starburst clusters. We aimed at identifying the massive stellar content and reconstructing the star formation history of the W51 giant molecular cloud. We performed near-infrared imaging and K-band spectroscopy of the massive stars in W51. We analysed the stellar populations using colour-magnitude and colour-colour diagrams and compared the properties of the spectroscopically identified stars with stellar evolution models. We derive the ages of the different sub-clusters in W51 and, based on our spectroscopy derive an age for W51 of 3Myrs or less. The age of the P Cygni star LS1 and the presence of two still forming proto- clusters suggests that the star formation history of W51 is more complex than a single burst. We did not find evidence for triggered star formation and we concluded that the star formation in W51 is multi seeded. We finally concluded that W51 is a OB association where different sub-clusters form over a time span of at least 3-5Myrs.