- ID:
- ivo://CDS.VizieR/J/ApJS/241/12
- Title:
- The Asteroseismic Target List (ATL) for TESS
- Short Name:
- J/ApJS/241/12
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the target list of solar-type stars to be observed in short-cadence (2 minute) for asteroseismology by the NASA Transiting Exoplanet Survey Satellite (TESS) during its 2 year nominal survey mission. The solar-like Asteroseismic Target List (ATL) is comprised of bright, cool main-sequence and subgiant stars and forms part of the larger target list of the TESS Asteroseismic Science Consortium. The ATL uses the Gaia Data Release 2 and the Extended Hipparcos Compilation (XHIP) to derive fundamental stellar properties, to calculate detection probabilities, and to produce a rank- ordered target list. We provide a detailed description of how the ATL was produced and calculate expected yields for solar-like oscillators based on the nominal photometric performance by TESS. We also provide a publicly available source code that can be used to reproduce the ATL, thereby enabling comparisons of asteroseismic results from TESS with predictions from synthetic stellar populations.
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- ID:
- ivo://CDS.VizieR/J/ApJ/856/158
- Title:
- The B[e] phenomenon. VII. AS 386 follow-up
- Short Name:
- J/ApJ/856/158
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report the results of spectroscopic and photometric observations of the emission-line object AS 386. For the first time we found that it exhibits the B[e] phenomenon and fits the definition of an FS CMa type object. The optical spectrum shows the presence of a B-type star with the following properties: Teff=11000+/-500K, log L/L_{sun}_=3.7+/-0.3, a mass of 7+/-1M_{sun}_, and a distance D=2.4+/-0.3kpc from the Sun. We detected regular radial velocity variations of both absorption and emission lines with the following orbital parameters: Porb=131.27+/-0.09 days, semiamplitude K1=51.7+/-3.0km/s, systemic radial velocity {gamma}=-31.8+/-2.6km/s, and a mass function of f(m)=1.9+/-0.3M_{sun}_. AS 386 exhibits irregular variations of the optical brightness (V=10.92+/-0.05mag), while the near-IR brightness varies up to ~0.3mag following the spectroscopic period. We explain this behavior by a variable illumination of the dusty disk inner rim by the B-type component. Doppler tomography based on the orbital variations of emission-line profiles shows that the material is distributed near the B-type component and in a circumbinary disk. We conclude that the system has undergone a strong mass transfer that created the circumstellar material and increased the B-type component mass. The absence of any traces of a secondary component, whose mass should be >=7M_{sun}_, suggests that it is most likely a black hole.
- ID:
- ivo://CDS.VizieR/J/ApJ/757/83
- Title:
- The Blanco Cosmology Survey (BCS)
- Short Name:
- J/ApJ/757/83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Blanco Cosmology Survey (BCS) is a 60 night imaging survey of ~80deg^2^ of the southern sky located in two fields: (5hr,-55{deg}) and (23hr,-55{deg}). The survey was carried out between 2005 and 2008 in griz bands with the Mosaic2 imager on the Blanco 4m telescope. The primary aim of the BCS survey is to provide the data required to optically confirm and measure photometric redshifts for Sunyaev-Zel'dovich effect selected galaxy clusters from the South Pole Telescope and the Atacama Cosmology Telescope. We process and calibrate the BCS data, carrying out point-spread function-corrected model-fitting photometry for all detected objects. The median 10{sigma} galaxy (point-source) depths over the survey in griz are approximately 23.3 (23.9), 23.4 (24.0), 23.0 (23.6), and 21.3 (22.1), respectively. The astrometric accuracy relative to the USNO-B survey is ~45mas. We calibrate our absolute photometry using the stellar locus in grizJ bands, and thus our absolute photometric scale derives from the Two Micron All Sky Survey, which has ~2% accuracy. The scatter of stars about the stellar locus indicates a systematic floor in the relative stellar photometric scatter in griz that is ~1.9%, ~2.2%, ~2.7%, and ~2.7%, respectively. A simple cut in the AstrOmatic star-galaxy classifier spread_ model produces a star sample with good spatial uniformity. We use the resulting photometric catalogs to calibrate photometric redshifts for the survey and demonstrate scatter {delta}z/(1+z)=0.054 with an outlier fraction {eta}<5% to z~1. We highlight some selected science results to date and provide a full description of the released data products.
- ID:
- ivo://CDS.VizieR/J/AJ/151/82
- Title:
- The 4 brightest red giants in the UFD galaxy Ret 2
- Short Name:
- J/AJ/151/82
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The ultra-faint dwarf (UFD) galaxy Reticulum 2 (Ret 2) was recently discovered in images obtained by the Dark Energy Survey (Diehl et al. 2014SPIE.9149E..0VD). We have observed the four brightest red giants in Ret 2 at high spectral resolution using the Michigan/Magellan Fiber System. We present detailed abundances for as many as 20 elements per star, including 12 elements heavier than the Fe group. We confirm previous detection of high levels of r-process material in Ret 2 (mean [Eu/Fe]=+1.69+/-0.05) found in three of these stars (mean [Fe/H]=-2.88+/-0.10). The abundances closely match the r-process pattern found in the well-studied metal-poor halo star CS 22892-052. Such r-process-enhanced stars have not been found in any other UFD galaxy, though their existence has been predicted by at least one model. The fourth star in Ret 2 ([Fe/H]=-3.42+/-0.20) contains only trace amounts of Sr ([Sr/Fe]=-1.73+/-0.43) and no detectable heavier elements. One r-process enhanced star is also enhanced in C (natal [C/Fe]~+1.1). This is only the third such star known, which suggests that the nucleosynthesis sites leading to C and r-process enhancements are decoupled. The r-process-deficient star is enhanced in Mg ([Mg/Fe]=+0.81+/-0.14), and the other three stars show normal levels of {alpha}-enhancement (mean [Mg/Fe]=+0.34+/-0.03). The abundances of other {alpha} and Fe-group elements closely resemble those in UFD galaxies and metal-poor halo stars, suggesting that the nucleosynthesis that led to the large r-process enhancements either produced no light elements or produced light-element abundance signatures indistinguishable from normal supernovae.
- ID:
- ivo://CDS.VizieR/J/AJ/126/197
- Title:
- The Carina projects. I. Bright variables stars
- Short Name:
- J/AJ/126/197
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new BV time series data of the Carina dwarf spheroidal galaxy (dSph). Current data cover an area of ~0.3deg^2^ around the center of the galaxy and allow us to identify 92 variables. Among them 75 are RR Lyrae stars, 15 are bona fide anomalous Cepheids, one might be a Galactic field RR Lyrae star, and one is located along the Carina red giant branch. Expanding upon the seminal photographic investigation by Saha, Monet, & Seitzer (1986AJ.....92..302S) we supply, for the first time, accurate estimates of their pulsation parameters (periods, amplitudes, mean magnitudes, and colors) on the basis of CCD photometry. Approximately 50% of both RR Lyrae stars and anomalous Cepheids are new identifications. Among the RR Lyrae sample, six objects are new candidate double-mode (RRd) variables. On the basis of their pulsation properties we estimate that two variables (V158, V182) are about 50% more massive than typical RR Lyrae stars, while the bulk of the anomalous Cepheids are roughly a factor of 2 more massive than fundamental-mode (RRab) RR Lyrae stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/830/126
- Title:
- The Carina project. X. Radial velocities
- Short Name:
- J/ApJ/830/126
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new radial velocity (RV) measurements of old (horizontal branch) and intermediate-age (red clump) stellar tracers in the Carina dwarf spheroidal. They are based on more than 2200 low-resolution spectra collected with VIMOS at Very Large Telescope (VLT). The targets are faint (20<~V<~21.5mag), but the accuracy at the faintest limit is <=9km/s. These data were complemented with RV measurements either based on spectra collected with FORS2 and FLAMES/GIRAFFE at VLT or available in the literature. We ended up with a sample of 2748 stars and among them, 1389 are candidate Carina stars. We found that the intermediate-age stellar component shows a well-defined rotational pattern around the minor axis. The western and the eastern side of the galaxy differ by +5 and -4km/s when compared with the main RV peak. The old stellar component is characterized by a larger RV dispersion and does not show evidence of the RV pattern. We compared the observed RV distribution with N-body simulations for a former disky dwarf galaxy orbiting a giant Milky Way-like galaxy. We rotated the simulated galaxy by 60{deg} with respect to the major axis, we kept the observer on the orbital plane of the dwarf and extracted a sample of stars similar to the observed one. Observed and predicted V_rot_/{sigma} ratios across the central regions are in remarkable agreement. This evidence indicates that Carina was a disky dwarf galaxy that experienced several strong tidal interactions with the Milky Way. Owing to these interactions, Carina transformed from a disky to a prolate spheroid and the rotational velocity transformed into random motions.
- ID:
- ivo://CDS.VizieR/J/ApJS/197/21
- Title:
- The Carnegie-Irvine Galaxy Survey (CGS). I.
- Short Name:
- J/ApJS/197/21
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Carnegie-Irvine Galaxy Survey (CGS) is a long-term program to investigate the photometric and spectroscopic properties of a statistically complete sample of 605 bright (B_T_<12.9mag), southern ({delta}<0{deg}) galaxies using the facilities at Las Campanas Observatory. This paper, the first in a series, outlines the scientific motivation of CGS, defines the sample, and describes the technical aspects of the optical broadband (BVRI) imaging component of the survey, including details of the observing program, data reduction procedures, and calibration strategy. The overall quality of the images is quite high, in terms of resolution (median seeing ~1"), field of view (8.9'x8.9'), and depth (median limiting surface brightness ~27.5, 26.9, 26.4, and 25.3mag/arcsec^2^ in the B, V, R, and I bands, respectively). We prepare a digital image atlas showing several different renditions of the data, including three-color composites, star-cleaned images, stacked images to enhance faint features, structure maps to highlight small-scale features, and color index maps suitable for studying the spatial variation of stellar content and dust. In anticipation of upcoming science analyses, we tabulate an extensive set of global properties for the galaxy sample. These include optical isophotal and photometric parameters derived from CGS itself, as well as published information on multiwavelength (ultraviolet, U-band, near-infrared, far-infrared) photometry, internal kinematics (central stellar velocity dispersions, disk rotational velocities), environment (distance to nearest neighbor, tidal parameter, group, or cluster membership), and HI content.
- ID:
- ivo://CDS.VizieR/J/ApJS/243/24
- Title:
- The CASBaH galaxy redshift survey
- Short Name:
- J/ApJS/243/24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We describe the survey for galaxies in the fields surrounding nine sightlines to far-UV bright, z~1 quasars that define the COS Absorption Survey of Baryon Harbors (CASBaH) program. The photometry and spectroscopy that comprise the data set come from a mixture of public surveys (SDSS, DECaLS) and our dedicated efforts on private facilities (Keck, MMT, LBT). We report the redshifts and stellar masses for 5902 galaxies within ~10 comoving-Mpc of the sightlines with a median of \bar{z}=0.28 and \bar{M}_*_~10^10.1^M_{sun}_. This data set, publicly available as the CASBaH specDB, forms the basis of several recent and ongoing CASBaH analyses. Here, we perform a clustering analysis of the galaxy sample with itself (auto-correlation) and against the set of O VI absorption systems (cross-correlation) discovered in the CASBaH quasar spectra with column densities N(O^+5^)>=10^13.5^/cm^2^. For each, we describe the measured clustering signal with a power-law correlation function {xi}(r)=(r/r_0_)^-{gamma}^ and find that (r_0_,{gamma})=(5.48+/-0.07h_100_^-1^Mpc,1.33+/-0.04) for the auto-correlation and (6.00_-0.77_^+1.09^h_100_^-1^Mpc,1.25+/-0.18) for galaxy-OVI cross-correlation. We further estimate a bias factor of b_gg_=1.3+/-0.1 from the galaxy-galaxy auto-correlation, indicating the galaxies are hosted by halos with mass M_halo_~10^12.1+/-0.05^M_{sun}_. Finally, we estimate an OVI-galaxy bias factor b_OVI_=1.0+/-0.1 from the cross-correlation which is consistent with OVI absorbers being hosted by dark matter halos with typical mass M_halo_~10^11^M_{sun}_. Future works with upcoming data sets (e.g., CGM2) will improve upon these results and will assess whether any of the detected OVI arises in the intergalactic medium.
- ID:
- ivo://CDS.VizieR/J/A+A/597/A18
- Title:
- The central black hole in NGC 4414
- Short Name:
- J/A+A/597/A18
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present our mass estimate of the central black hole in the isolated spiral galaxy NGC 4414. Using natural guide star adaptive optics assisted observations with the Gemini Near-Infrared Integral Field Spectrometer (NIFS) and the natural seeing Gemini Multi-Object Spectrographs-North (GMOS), we derived two-dimensional stellar kinematic maps of NGC 4414 covering the central 1.5-arcsec and 10-arcsec, respectively, at a NIFS spatial resolution of 0.13-arcsec. The kinematic maps reveal a regular rotation pattern and a central velocity dispersion dip down to around 105km/s. We constructed dynamical methods using two different methods: Jeans anisotropic dynamical modeling and axisymmetric Schwarzschild modeling. Both modeling methods give consistent results, but we cannot constrain the lower mass limit and only measure an upper limit for the black hole mass of M_bh_=1.56x10^6^M_{sun}_ (at 3{sigma{ level) which is at least 1{sigma} below the recent Mbh-sigma_e relations. Further tests with dark matter, mass-to-light ratio variation and different light models confirm that our results are not dominated by uncertainties. The derived upper limit mass is not only below the Mbh-sigma_e relation, but is also five times lower than the lower limit black hole mass anticipated from the resolution limit of the sphere of influence. This proves that via high quality integral field data we are now able to push black hole measurements down to at least five times less than the resolution limit.
- ID:
- ivo://CDS.VizieR/J/ApJS/185/198
- Title:
- The Cepheus flare observed with IRAC and MIPS
- Short Name:
- J/ApJS/185/198
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present Spitzer Infrared Array Camera (IRAC; ~2deg^2^) and Multiband Imaging Photometer for Spitzer (MIPS; ~8deg^2^) observations of the Cepheus Flare, which is associated with the Gould Belt, at an approximate distance of ~300pc. Around 6500 sources are detected in all four IRAC bands, of which ~900 have MIPS 24um detections. We identify 133 young stellar object (YSO) candidates using color-magnitude diagram techniques, and a large number of the YSO candidates are associated with the NGC 7023 reflection nebula. Cross-identifications were made with the Guide Star Catalog II and the IRAS Faint Source Catalog, and spectral energy distributions (SEDs) were constructed. SED modeling was conducted to estimate the degree of infrared excess. It was found that a large majority of disks were optically thick accreting disks, suggesting that there has been little disk evolution in these sources. Nearest-neighbor clustering analysis identified four small protostellar groups (L1228, L1228N, L1251A, and L1251B) with 5-15 members each and the larger NGC 7023 association with 32 YSO members. The star-formation efficiency for cores with clusters of protostars and for those without clusters was found to be ~8% and ~1%, respectively. The cores L1155, L1241, and L1247 are confirmed to be starless down to our luminosity limit of L_bol_=0.06L_{sun}_.