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- ID:
- ivo://CDS.VizieR/J/ApJS/194/14
- Title:
- A Pan-Carina YSO catalog
- Short Name:
- J/ApJS/194/14
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a catalog of 1439 young stellar objects (YSOs) spanning the 1.42deg^2^ field surveyed by the Chandra Carina Complex Project (CCCP), which includes the major ionizing clusters and the most active sites of ongoing star formation within the Great Nebula in Carina. Candidate YSOs were identified via infrared (IR) excess emission from dusty circumstellar disks and envelopes, using data from the Spitzer Space Telescope (the Vela-Carina survey) and the Two-Micron All Sky Survey. We model the 1-24um IR spectral energy distributions of the YSOs to constrain physical properties. Our Pan-Carina YSO Catalog (PCYC) is dominated by intermediate-mass (2M_{sun}_<m<~10M_{sun}_) objects with disks, including Herbig Ae/Be stars and their less evolved progenitors. The PCYC provides a valuable complementary data set to the CCCP X-ray source catalogs, identifying 1029 YSOs in Carina with no X-ray detection. We also catalog 410 YSOs with X-ray counterparts, including 62 candidate protostars. Extrapolating over the stellar initial mass function scaled to the PCYC population, we predict a total population of >2x10^4^ YSOs and a present-day star formation rate (SFR) of >0.008M_{sun}_/yr. The global SFR in the Carina Nebula, averaged over the past ~5Myr, has been approximately constant.
- ID:
- ivo://CDS.VizieR/J/ApJ/727/83
- Title:
- A panchromatic study of BLAST counterparts
- Short Name:
- J/ApJ/727/83
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carry out a multi-wavelength study of individual galaxies detected by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) and identified at other wavelengths, using data spanning the radio to the ultraviolet (UV). We develop a Monte Carlo method to account for flux boosting, source blending, and correlations among bands, which we use to derive deboosted far-infrared (FIR) luminosities for our sample. We estimate total star-formation rates (SFRs) for BLAST counterparts with z<=0.9 by combining their FIR and UV luminosities. We assess that about 20% of the galaxies in our sample show indication of a type 1 active galactic nucleus, but their submillimeter emission is mainly due to star formation in the host galaxy. We compute stellar masses for a subset of 92 BLAST counterparts; these are relatively massive objects, with a median mass of ~10^11^M_{sun}_, which seem to link the 24um and Submillimetre Common-User Bolometer Array (SCUBA) populations, in terms of both stellar mass and star formation activity.
- ID:
- ivo://CDS.VizieR/J/AJ/148/81
- Title:
- APASS BVgri photometry of RAVE stars. I. Data
- Short Name:
- J/AJ/148/81
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We provide AAVSO Photometric All-Sky Survey (APASS) photometry in the Landolt BV and Sloan g'r'i' bands for all 425743 stars included in the fourth RAVE Data Release. The internal accuracy of the APASS photometry of RAVE stars, expressed as the error of the mean of data obtained and separately calibrated over a median of four distinct observing epochs and distributed between 2009 and 2013, is 0.013, 0.012, 0.012, 0.014, and 0.021mag for the B, V, g', r', and i' bands, respectively. The equally high external accuracy of APASS photometry has been verified on secondary Landolt and Sloan photometric standard stars not involved in the APASS calibration process and on a large body of literature data on field and cluster stars, confirming the absence of offsets and trends. Compared with the Carlsberg Meridian Catalog (CMC-15), APASS astrometry of RAVE stars is accurate to a median value of 0.098arcsec. Brightness distribution functions for the RAVE stars have been derived in all bands. APASS photometry of RAVE stars, augmented by 2MASS JHK infrared data, has been {chi}^2^ fitted to a densely populated synthetic photometric library designed to widely explore temperature, surface gravity, metallicity, and reddening. Resulting T_eff_ and E_B-V_, computed over a range of options, are provided and discussed, and will be kept updated in response to future APASS and RAVE data releases. In the process, we find that the reddening caused by a homogeneous slab of dust, extending for 140pc on either side of the Galactic plane and responsible for E_B-V_^poles^=0.036+/-0.002 at the Galactic poles, is a suitable approximation of the actual reddening encountered at Galactic latitudes|b|>=25{deg}.
- ID:
- ivo://CDS.VizieR/J/other/JAD/20.4
- Title:
- 180 APASS variable stars in Aquarius
- Short Name:
- J/other/JAD/20.4
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- During a search for RR Lyr variable stars candidate members of the Aquarius stream, which led to the discovery of 71 such objects, we also discovered an additional 180 variables which are presented in this paper. Of them, 141 were previously reported as variables and 39 are brand new. For all 180 objects, we provide: our epoch photometry, accurate positions, mean magnitude and amplitude of variation in Landolt B,V and Sloan g, r, i bands, cross-identification with WISE, 2MASS and GALEX surveys, accurate BVRCICgri photometric sequences and finding charts identifying the variable and the stars of the photometric sequence provided to support follow-up observations. We carried out a Fourier search on all 39 new variables and found periods for 11 of them.
- ID:
- ivo://CDS.VizieR/J/A+A/659/A89
- Title:
- Aperture-corrected SN Ia host properties
- Short Name:
- J/A+A/659/A89
- Date:
- 11 Mar 2022 07:19:46
- Publisher:
- CDS
- Description:
- We use type Ia supernova (SN Ia) data obtained by the Sloan Digital Sky Survey-II Supernova Survey (SDSS-II SNS) in combination with the publicly available SDSS DR16 fiber spectroscopy of supernova (SN) host galaxies to correlate SN Ia light-curve parameters and Hubble residuals with several host galaxy properties. Fixed-aperture fiber spectroscopy suffers from aperture effects: the fraction of the galaxy covered by the fiber varies depending on its projected size on the sky, and thus measured properties are not representative of the whole galaxy. The advent of integral field spectroscopy has provided a way to correct the missing light, by studying how these galaxy parameters change with the aperture size. Here we study how the standard SN host galaxy relations change once global host galaxy parameters are corrected for aperture effects. We recover previous trends on SN Hubble residuals with host galaxy properties, but we find that discarding objects with poor fiber coverage instead of correcting for aperture loss introduces biases into the sample that affect SN host galaxy relations. The net effect of applying the commonly used g-band fraction criterion is that intrinsically faint SNe Ia in high-mass galaxies are discarded, thus artificially increasing the height of the mass step by 0.02 mag and its significance. Current and next-generation fixed-aperture fiber-spectroscopy surveys, such as DES, DESI, or TiDES in 4MOST, that aim to study SN and galaxy correlations must consider, and correct for, these effects.
- ID:
- ivo://CDS.VizieR/J/ApJ/671/333
- Title:
- Aperture photometry in NGC 5194
- Short Name:
- J/ApJ/671/333
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have studied the relationship between the star formation rate (SFR), surface density, and gas surface density in the spiral galaxy M51a (NGC 5194), using multiwavelength data obtained as part of the Spitzer Infrared Nearby Galaxies Survey (SINGS). We introduce a new SFR index based on a linear combination of Halpha emission-line and 24um continuum luminosities, which provides reliable extinction-corrected ionizing fluxes and SFR densities over a wide range of dust attenuations.
- ID:
- ivo://CDS.VizieR/J/A+A/654/A6
- Title:
- Aperture photometry of the M31 PHAT clusters
- Short Name:
- J/A+A/654/A6
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- This study is the sixth of a series that investigates degeneracy and stochasticity problems present in the determination of the age, mass, extinction, and metallicity of partially resolved or unresolved star clusters in external galaxies when using Hubble Space Telescope broadband photometry. In the fifth publication, it was noticed that inconsistencies in cluster colour indices, which arise due to projected foreground and background stars on the apertures, enhance age-metallicity-extinction degeneracies. In this work we aim to present new aperture photometry results for a sample of star clusters from the M31 Panchromatic Hubble Andromeda Treasury (PHAT) survey. We employed two methods of aperture photometry. The first method is ordinary aperture photometry to measure total cluster fluxes. The second method was introduced to avoid the brightest foreground and background stars that project onto large apertures. This method employs smaller apertures, adapted to cover a central part of clusters, and applies an aperture correction, derived for the F475W passband, to other passbands.We note that this procedure is valid only for clusters without prominent systematic gradients of colour indices beyond half-light radii. We present two catalogues of star cluster aperture photometry (produced by applying ordinary aperture photometry and adaptive aperture photometry methods) with estimated uncertainties for a sample of 1181 star clusters from the M31 PHAT survey. Compared to the M31 PHAT fundamental star cluster aperture photometry catalogue published by Johnson et al., there are changes made in the following: cluster centre coordinates, aperture sizes, and sky background estimates.
- ID:
- ivo://CDS.VizieR/J/A+A/555/A24
- Title:
- Aperture-synthesis imaging of Antares
- Short Name:
- J/A+A/555/A24
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present aperture-synthesis imaging of the red supergiant Antares (alpha Sco) in the CO first overtone lines. Our goal is to probe the structure and dynamics of the outer atmosphere.
- ID:
- ivo://CDS.VizieR/J/A+A/607/A78
- Title:
- APEX and IRAM spectra of CK Vul (Nova 1670)
- Short Name:
- J/A+A/607/A78
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- CK Vulpeculae (CK Vul) is an enigmatic star whose outburst was observed in 1670-72. A stellar-merger event was proposed to explain its ancient eruption. We aim to investigate the composition of the molecular gas recently discovered in the remnant of CK Vul. Deriving the chemical, elemental, and isotopic composition is crucial for identifying the nature of the object and obtaining clues on its progenitor(s). We observed millimeter and submillimeter-wave spectra of CK Vul using the IRAM 30m and APEX telescopes. Radiative-transfer modeling of the observed molecular features was performed to yield isotopic ratios for various elements. The spectra of CK Vul reveal a very rich molecular environment of low excitation (T_ex_~<12K). Atomic carbon and twenty seven different molecules, including two ions, were identified. They range from simple diatomic to complex polyatomic species of up to seven atoms large. The chemical composition of the molecular gas is indicative of carbon and nitrogen-driven chemistry but oxides are also present. Additionally, the abundance of F may be enhanced. The spectra are rich in isotopologues that are very rare in most known sources. All stable isotopes of C, N, O, Si, and S are observed and their isotopic ratios are derived. The composition of the remnant's molecular gas is most peculiar and gives rise to a very unique millimeter and submillimeter spectrum. The observation of ions and complex molecules suggests the presence of a photoionizing source but its nature (a central star or shocks) remains unknown. The elemental and isotopic composition of the gas cannot be easily reconciled with standard nucleosynthesis but processing in hot CNO cycles and partial He burning can explain most of the chemical peculiarities. The isotopic ratios of CK Vul are remarkably close to those of presolar nova grains but the link of Nova 1670 to objects responsible for these grains is unclear.
