- ID:
- ivo://CDS.VizieR/J/AJ/153/170
- Title:
- The M33 Synoptic Stellar Survey. II. Mira variables
- Short Name:
- J/AJ/153/170
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the discovery of 1847 Mira candidates in the Local Group galaxy M33 using a novel semi-parametric periodogram technique coupled with a random forest classifier. The algorithms were applied to ~2.4*10^5^ I-band light curves previously obtained by the M33 Synoptic Stellar Survey. We derive preliminary period-luminosity relations at optical, near-infrared, and mid-infrared wavelengths and compare them to the corresponding relations in the Large Magellanic Cloud.
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- ID:
- ivo://CDS.VizieR/J/ApJ/846/93
- Title:
- The multiplicity of M dwarfs in young moving groups
- Short Name:
- J/ApJ/846/93
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We image 104 newly identified low-mass (mostly M-dwarf) pre-main sequence (PMS) members of nearby young moving groups (YMGs) with Magellan Adaptive Optics (MagAO) and identify 27 stellar binaries with instantaneous projected separation as small as 40mas. Fifteen were previously unknown. The total number of multiple systems in this sample including spectroscopic and visual binaries from the literature is 36, giving a raw stellar multiplicity rate of at least 35_-4_^+5^% for this population. In the separation range of roughly 1-300au in which infrared AO imaging is most sensitive, the raw multiplicity rate is at least 24_-4_^+5^% for binaries resolved by the MagAO infrared camera (Clio). The M-star subsample of 87 stars yields a raw multiplicity of at least 30_-4_^+5^% over all separations, 21_-4_^+5^% for secondary companions resolved by Clio from 1 to 300au (23_-4_^+5^% for all known binaries in this separation range). A combined analysis with binaries discovered by the Search for Associations Containing Young stars shows that stellar multiplicity fraction as a function of mass over the range of 0.2 to 1.2M_{sun}_ appears to be linearly flat, in contrast to the field, where multiplicity increases with mass. After bias corrections are applied, the multiplicity of low-mass YMG members (0.2-0.6M_{sun}_) is in excess of the field. The overall multiplicity fraction is also consistent with being constant in age and across YMGs, which suggests that multiplicity rates for this mass range are largely set by 10Myr without appreciable evolution thereafter.
- ID:
- ivo://CDS.VizieR/J/ApJS/209/31
- Title:
- The MYStIX IR-Excess Source catalog (MIRES)
- Short Name:
- J/ApJS/209/31
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Massive Young Star-Forming Complex Study in Infrared and X-rays (MYStIX) project provides a comparative study of 20 Galactic massive star-forming complexes (d=0.4-3.6kpc). Probable stellar members in each target complex are identified using X-ray and/or infrared data via two pathways: X-ray detections of young/massive stars with coronal activity/strong winds or (2) infrared excess (IRE) selection of young stellar objects (YSOs) with circumstellar disks and/or protostellar envelopes. We present the methodology for the second pathway using Spitzer/IRAC, 2MASS, and UKIRT imaging and photometry. Although IRE selection of YSOs is well-trodden territory, MYStIX presents unique challenges. The target complexes range from relatively nearby clouds in uncrowded fields located toward the outer Galaxy (e.g., NGC 2264, the Flame Nebula) to more distant, massive complexes situated along complicated, inner Galaxy sightlines (e.g., NGC 6357, M17). We combine IR spectral energy distribution (SED) fitting with IR color cuts and spatial clustering analysis to identify IRE sources and isolate probable YSO members in each MYStIX target field from the myriad types of contaminating sources that can resemble YSOs: extragalactic sources, evolved stars, nebular knots, and even unassociated foreground/background YSOs. Applying our methodology consistently across 18 of the target complexes, we produce the MYStIX IRE Source (MIRES) Catalog comprising 20719 sources, including 8686 probable stellar members of the MYStIX target complexes. We also classify the SEDs of 9365 IR counterparts to MYStIX X-ray sources to assist the first pathway, the identification of X-ray-detected stellar members.
- ID:
- ivo://CDS.VizieR/J/MNRAS/482/5167
- Title:
- The 2M-ZoA galaxy catalogue
- Short Name:
- J/MNRAS/482/5167
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a homogeneous 2MASS bright galaxy catalogue at low Galactic latitudes (|b|<=10.0{deg}, called Zone of Avoidance) which is complete to a Galactic extinction-corrected magnitude of KS^o^<=11.25m. It also includes galaxies in regions of high foreground extinctions (E(B-V)>0.95mag) situated at higher latitudes. This catalogue forms the basis of studies of large-scale structures, flow fields and extinction across the ZoA and complements the ongoing 2MASS Redshift and Tully-Fisher surveys. It comprises 3763 galaxies, 70% of which have at least one radial velocity measurement in the literature. The catalogue is complete up to star density levels of logN*/deg^2^<4.5 and at least for A(K)<0.6mag and likely as high as A(K)=20mag. Thus the ZoA in terms of bright NIR galaxies covers only 2.5-4% of the whole sky. We use a diameter-dependent extinction correction to compare our sample with an unobscured, high-latitude sample. While the correction to the Ks -band magnitude is sufficient, the corrected diameters are too small by about 4" on average. The omission of applying such a diameter-dependent extinction correction may lead to a biased flow field even at intermediate extinction values as found in the 2MRS survey. A slight dependence of galaxy colour with stellar density indicates that unsubtracted foreground stars make galaxies appear bluer. Furthermore, far-infrared sources in the DIRBE/IRAS extinction maps that were not removed at low latitudes affect the foreground extinction corrections of three galaxies and may weakly affect a further estimated ~20% of our galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJS/193/25
- Title:
- The NAN complex. II. MIPS observations
- Short Name:
- J/ApJS/193/25
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present observations of ~7deg^2^ of the North American and Pelican Nebulae region at 24, 70, and 160um with the Spitzer Space Telescope Multiband I] ing Photometer for Spitzer (MIPS). We incorporate the MIPS observations with earlier Spitzer Infrared Array Camera (IRAC) observations, as well as archival near-infrared (IR) and optical data. We use the MIPS data to identify 1286 young stellar object (YSO) candidates. IRAC data alone can identify 806 more YSO candidates, for a total of 2076 YSO candidates. Prior to the Spitzer observations, there were only ~200 YSOs known in this region. Three subregions within the complex are highlighted as clusters: the Gulf of Mexico, the Pelican, and the Pelican's Hat. The Gulf of Mexico cluster is subject to the highest extinction (A_V_ at least ~30) and has the widest range of infrared colors of the three clusters, including the largest excesses and by far the most point-source detections at 70um. Just 3% of the cluster members were previously identified; we have redefined this cluster as about 10-100 times larger (in projected area) than was previously realized.
- ID:
- ivo://CDS.VizieR/J/ApJ/697/787
- Title:
- The NAN complex. I. IRAC observations
- Short Name:
- J/ApJ/697/787
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a 9deg^2^ map of the North American and Pelican Nebulae regions obtained in all four Infrared Array Camera (IRAC) channels with the Spitzer Space Telescope. The resulting photometry is merged with that at JHKs from Two Micron All Sky Survey and a more spatially limited BVI survey from previous ground-based work. We use a mixture of color-color diagrams to select a minimally contaminated set of more than 1600 objects that we claim are young stellar objects (YSOs) associated with the star-forming region. Because our selection technique uses infrared excess as a requirement, our sample is strongly biased against inclusion of Class III YSOs. The distribution of IRAC spectral slopes for our YSOs indicates that most of these objects are Class II, with a peak toward steeper spectral slopes but a substantial contribution from a tail of Flat spectrum and Class I type objects. By studying the small fraction of the sample that is optically visible, we infer a typical age of a few Myr for the low-mass population. The young stars are clustered, with about a third of them located in eight clusters that are located within or near the LDN 935 dark cloud. Half of the YSOs are located in regions with surface densities higher than 1000YSOs/deg^2^. The Class I objects are more clustered than the Class II stars.
- ID:
- ivo://CDS.VizieR/J/ApJ/858/11
- Title:
- The NIR tip of RGB. I. JHK photometry of IC1613
- Short Name:
- J/ApJ/858/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Based on observations from the FourStar near-infrared camera on the 6.5m Baade-Magellan telescope at Las Campanas, Chile, we present calibrations of the JHK luminosities of stars defining the tip of the red giant branch (TRGB) in the halo of the Local Group dwarf galaxy IC1613. We employ metallicity- independent (rectified) T-band magnitudes-constructed using J-, H-, and K-band magnitudes and both (J-H) and (J-K) colors to flatten the upward-sloping red giant branch tips as otherwise seen in their apparent color-magnitude diagrams. We describe and quantify the advantages of working at these particular near-infrared wavelengths, which are applicable to both the Hubble Space Telescope (HST) and the James Webb Space Telescope (JWST). We also note that these same wavelengths can be accessed from the ground for an eventual tie-in to Gaia for absolute astrometry and parallaxes to calibrate the intrinsic luminosity of the TRGB. Adopting the color terms derived from the IC 1613 data, as well as the zero points from a companion study of the Large Magellanic Cloud, whose distance is anchored to the geometric distances of detached eclipsing binaries, we find a true distance modulus of 24.32+/-0.02 (statistical) +/-0.05mag (systematic) for IC 1613, which compares favorably with the recently published multi-wavelength, multi-method consensus modulus of 24.30+/-0.05mag by Hatt et al. (2017, J/ApJ/845/146).
- ID:
- ivo://CDS.VizieR/J/ApJS/179/1
- Title:
- The OPTX project: CLANS, CLASXS and CDF-N
- Short Name:
- J/ApJS/179/1
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the redshift catalogs for the X-ray sources detected in the Chandra Deep Field-North (CDF-N), the Chandra Large Area Synoptic X-ray Survey (CLASXS), and the Chandra Lockman Area North Survey (CLANS). The catalogs for the CDF-N and CLASXS fields include redshifts from previous work, while the redshifts for the CLANS field are all new. For fluxes above 10^-14^ergs/cm^2^/s (2-8keV) we have redshifts for 76% of the sources. We extend the redshift information for the full sample using photometric redshifts. The goal of the OPTX Project is to use these three surveys, which are among the most spectroscopically complete surveys to date, to analyze the effect of spectral type on the shape and evolution of the X-ray luminosity functions and to compare the optical spectral types with the X-ray spectral properties. We also present the CLANS X-ray catalog. The nine ACIS-I fields cover a solid angle of ~0.6deg^2^ and reach fluxes of 7x10^-16^ergs/cm^2^/s (0.5-2keV) and 3.5x10^-15^ergs/cm^2^/s (2-8keV). We find a total of 761 X-ray point sources. In addition, we present the optical and infrared photometric catalog for the CLANS X-ray sources, as well as updated optical and infrared photometric catalogs for the X-ray sources in the CLASXS and CDF-N fields.
- ID:
- ivo://CDS.VizieR/J/ApJ/841/84
- Title:
- Theoretical framework for RR Lyrae. II. MIR data
- Short Name:
- J/ApJ/841/84
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new theoretical period-luminosity-metallicity (PLZ) relations for RR Lyrae stars (RRLs) at Spitzer and WISE wavelengths. The PLZ relations were derived using nonlinear, time-dependent convective hydrodynamical models for a broad range of metal abundances (Z=0.0001-0.0198). In deriving the light curves, we tested two sets of atmospheric models and found no significant difference between the resulting mean magnitudes. We also compare our theoretical relations to empirical relations derived from RRLs in both the field and in the globular cluster M4. Our theoretical PLZ relations were combined with multi-wavelength observations to simultaneously fit the distance modulus, {mu}0, and extinction, A_V_, of both the individual Galactic RRL and of the cluster M4. The results for the Galactic RRL are consistent with trigonometric parallax measurements from Gaia's first data release. For M4, we find a distance modulus of {mu}0=11.257+/-0.035mag with A_V_=1.45+/-0.12mag, which is consistent with measurements from other distance indicators. This analysis has shown that, when considering a sample covering a range of iron abundances, the metallicity spread introduces a dispersion in the PL relation on the order of 0.13mag. However, if this metallicity component is accounted for in a PLZ relation, the dispersion is reduced to ~0.02mag at mid-infrared wavelengths.
- ID:
- ivo://CDS.VizieR/II/349
- Title:
- The Pan-STARRS release 1 (PS1) Survey - DR1
- Short Name:
- II/349
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) is a system for wide-field astronomical imaging developed and operated by the Institute for Astronomy at the University of Hawaii. Pan-STARRS1 (PS1) is the first part of Pan-STARRS to be completed and is the basis for Data Release 1 (DR1). The PS1 survey used a 1.8m telescope and its 1.4 Gigapixel camera (GPC1) to image the sky in five broadband filters (g, r, i, z, y). PS1 took approximately 370000 exposures from 2010 to 2015. The PS1 camera surveyed the sky using 5 filters: g, r, i, z, and y. The effective wavelengths (and spectral resolutions) of these 5 filters are 481nm (R=3.5), 617nm (R=4.4), 752nm (R=5.8), 866nm (R=8.3), and 962nm (R=11.6), respectively. Please refer to Table 4 in Tonry+ (2012, J/ApJ/750/99) for bandpass details. Schlafly+ (2012ApJ...756..158S) provides updated zeropoints in Table 1. Data for this catalog has been retrieved from STScI and was built from ObjectThin and StackObjectThin tables with nDetections>2.
