- ID:
- ivo://CDS.VizieR/J/ApJ/721/98
- Title:
- Morphology of 70um COSMOS galaxies
- Short Name:
- J/ApJ/721/98
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We analyze the morphological properties of a large sample of 1503 70um selected galaxies in the COSMOS field spanning the redshift range 0.01<z<3.5 with a median redshift of 0.5 and an infrared luminosity range of 10^8^<L_IR_(8-1000um)<10^14^L_{sun}_ with a median luminosity of 10^11.4^L_{sun}_. In general, these galaxies are massive, with a stellar mass range of 10^10^-10^12^M_{sun}_, and luminous, with -25<M_K_<-20. The precise fraction of mergers in any given L_IR_ bin varies by redshift due to sources at z>1 being difficult to classify and subject to the effects of bandpass shifting; therefore, these numbers can only be considered lower limits. At z<1, where the morphological classifications are most robust, major mergers clearly dominate the ULIRG population (~50%-80%) and are important for the LIRG population (~25%-40%). At z>1, the fraction of major mergers is lower, but is at least 30%-40% for ULIRGs. In a comparison of our visual classifications with several automated classification techniques we find general agreement; however, the fraction of identified mergers is underestimated due to automated classification methods being sensitive to only certain timescales of a major merger. The distribution of the U-V color of the galaxies in our sample peaks in the green valley (<U-V>=1.1) with a large spread at bluer and redder colors and with the major mergers peaking more strongly in the green valley than the rest of the morphological classes.
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- ID:
- ivo://CDS.VizieR/J/AJ/136/1221
- Title:
- Most luminous LMC sources at 8{mu}m
- Short Name:
- J/AJ/136/1221
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- To ascertain the nature of the brightest compact mid-infrared (mid-IR) sources in the Large Magellanic Cloud (LMC), we have applied an updated version of Buchanan et al.'s (2006AJ....132.1890B) Two Micron All Sky Survey (2MASS)-Midcourse Space Experiment (MSX) color classification system, which is based on the results of Spitzer Space Telescope spectroscopy, to a mid-IR (8um) flux-limited sample of 250 LMC objects for which 2MASS and MSX photometry is available. The resulting 2MASS-MSX ("JHK8") color-based classifications of these sources, which constitute the most mid-IR-luminous objects in the LMC, were augmented, cross-checked, and corrected where necessary via a variety of independent means, such that only 46 sources retain tentative classifications and only 10 sources cannot be classified at all. The sample is found to consist primarily of carbon-rich asymptotic giant branch (AGB) stars (35%), red supergiants (RSGs) (18%), and compact HII regions (32%), with additional, small populations of oxygen-rich AGB stars (~5%), dusty, early-type emission-line stars (~3%), and foreground, O-rich AGB stars in the Milky Way (~3%).
- ID:
- ivo://CDS.VizieR/J/ApJ/886/40
- Title:
- Most luminous SPIRITS IR transients follow-up obs.
- Short Name:
- J/ApJ/886/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a systematic study of the most luminous (MIR [Vega magnitudes] brighter than -14) infrared (IR) transients discovered by the SPitzer InfraRed Intensive Transients Survey (SPIRITS) between 2014 and 2018 in nearby galaxies (D<35Mpc). The sample consists of nine events that span peak IR luminosities of M_[4.5],peak_ between -14 and -18.2, show IR colors between 0.2<([3.6]-[4.5])<3.0, and fade on timescales between 55d<t_fade_<480d. The two reddest events (A_V_>12) show multiple, luminous IR outbursts over several years and have directly detected, massive progenitors in archival imaging. With analyses of extensive, multiwavelength follow-up, we suggest the following possible classifications: five obscured core-collapse supernovae (CCSNe), two erupting massive stars, one luminous red nova, and one intermediate-luminosity red transient. We define a control sample of all optically discovered transients recovered in SPIRITS galaxies and satisfying the same selection criteria. The control sample consists of eight CCSNe and one Type Iax SN. We find that 7 of the 13 CCSNe in the SPIRITS sample have lower bounds on their extinction of 2<A_V_<8. We estimate a nominal fraction of CCSNe in nearby galaxies that are missed by optical surveys as high as 38.5_-21.9_^+26.0^% (90% confidence). This study suggests that a significant fraction of CCSNe may be heavily obscured by dust and therefore undercounted in the census of nearby CCSNe from optical searches.
- ID:
- ivo://CDS.VizieR/J/other/Ap/44.335
- Title:
- M stars in Cepheus region
- Short Name:
- J/other/Ap/44.33
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The results of a spectral classification of 257 M stars observed in the Cepheus region are given. Their equatorial coordinates, photographic stellar magnitudes, and spectral subtypes were determined. These stars are giants and supergiants, in all probability. None of them appear in a catalog of variable stars. It is assumed that variability might be detected in many of them upon further study. Fifty-two of the stars have been identified with infrared sources. In addition to the originally published data, magnitudes, positions, cross-identifications and notes have been added in May 2002. (see the "History" section below)
- ID:
- ivo://CDS.VizieR/V/114
- Title:
- MSX6C Infrared Point Source Catalog
- Short Name:
- V/114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Version 2.3 of the Midcourse Space Experiment (MSX) Point Source Catalog (PSC), which supersedes the version (1.2) that was released in 1999 (Cat. V/107), contains over 100,000 more sources than the previous version. The photometry is based on co-added image plates, as opposed to single-scan data, which results in improved sensitivity and hence reliability in the fluxes. Comparison with Tycho-2 positions indicates that the astrometric accuracy of the new catalog is more than 1'' better than that in Version 1.2. In addition to the Galactic plane, Areas Missed by the Infrared Astronomical Satellite (IRAS), and the Large Magellanic Cloud, which were included in the previous catalog, Version 2.3 includes data from the Small Magellanic Cloud, eight nearby galaxies, and several molecular clouds and star forming regions. The infrared instrument on MSX was named SPIRIT III; it was a 35cm clear aperture off-axis telescope with five line scanned infrared focal plane arrays of 18.3arcsec square pixels, with a high sensitivity (0.1Jy at 8.3micron). The 6 bands are B1 (4.29micron, FWHM 4.22-4.36micron), B2 (4.25micron, 4.24-4.45micron), A (8.28micron, 6.8-10.8micron), C (12.13micron, 11.1-13.2micron), D (14.65micron, 13.5-15.9micron), and E (21.34micron, 18.2-25.1micron). The MSX catalog names of the sources have been defined according to International Astronomical Union (IAU) conventions with a unique identifier combined with the position of the source. In this case, the MSX PSC V2.3 sources are named using the convention MSX6C GLLL.llll+/-BB.bbbb, where MSX6C denotes that this is MSX data run using Version 6.0 of the CONVERT software, and GLLL.llll+/-BB.bbbb gives the Galactic coordinates of the source. (Names in the minicatalogs may differ slightly from those given in Kraemer et al. 2002AJ....124.2990K, 2003AJ....126.1423K) For ease of handling, the main catalog is broken into six files: five for the Galactic plane survey, plus the primary high latitude regions (the IRAS gaps and the LMC). The supplementary catalogs are the singleton catalog, the low-reliability catalog, and minicatalogs for 19 selected regions. All catalogs have the same format. However, the minicatalogs for the galaxies (except the SMC) and Orion do not have all the fields filled in because they were solely created from the images, not from the Point Source Extractor; there are no singleton files for these regions. Also, the minicatalogs may not have singleton or low-reliability counterparts if no sources met the inclusion criteria. All told, there are a total of 45 data files.
- ID:
- ivo://CDS.VizieR/V/107
- Title:
- MSX5C Infrared Point Source Catalog
- Short Name:
- V/107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The principal objective of the astronomy experiments abroad the Midcourse Space Experiment (MSX) was to complete the census of the mid-infrared (4.2-25{mu}m) sky: the areas missed by the IRAS mission (about 4% of the sky was not surveyed by IRAS), and the Galactic Plane where the sensitivity of IRAS was degraded by confusion noise in the regions of high source densities or structured extended emission. The infrared instrument on MSX is named SPIRIT III; it is a 35cm clear aperture off-axis telescope with five line scanned infrared focal plane arrays of 18.3arcsec square pixels, with a high sensitivity (0.1Jy at 8.3{mu}m). The characteristics of the 6 bands B1, B2, A, C, D and E are summarized in the "Note (1)" below. The data are contained in 7 files according to the location on the sky: 5 are related to the Galactic Plane, one (non-plane) contains the IRAS gap catalog, the the lmc.dat file contains the observations of the Large Magellanic Cloud.
- ID:
- ivo://CDS.VizieR/J/AJ/124/2990
- Title:
- MSX galaxy observations
- Short Name:
- J/AJ/124/2990
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have imaged eight nearby spiral galaxies with the SPIRIT III infrared telescope on the Midcourse Space Experiment (MSX) satellite in the mid-infrared at 18" resolution at 8.3, 12.1, 14.7, and 21.3{mu}m. Each of the eight shows interesting structure not previously detected with older, lower resolution infrared data sets, such as a resolved nucleus or spiral structure. The MSX data are compared with existing data sets at ultraviolet, optical, and infrared wavelengths, including recent observations from the Infrared Space Observatory. The infrared structures in M83 and NGC 5055 show a striking similarity to the ultraviolet emission but are less similar to the optical emission. Several point sources with no identified counterparts at other wavelengths are found near M31, NGC 4945, M83, and M101. Over 200 previously known objects are also detected at 8{mu}m.
- ID:
- ivo://CDS.VizieR/V/98
- Title:
- MSX Infrared Astrometric Catalog
- Short Name:
- V/98
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The MSX Infrared Astrometric Catalog has been contructed as a tool for improving the pointing accuracy of infrared observations. The catalog contains 177,860 astrometric stars, 61,242 which have been identified with their infrared counterparts from IRAS catalogs and the Catalog of Infrared Observations through position and color matching. Infrared flux densities are predicted for 6 wavelength bands between 4 and 22um. The catalog identifications are complete to within the spatial coverage of current surveys for those astrometric stars brightest in the infrared. By predicting fluxes of astrometric stars without IR identifications we are able to extend the catalog to areas of the sky which were incomplete in the IRAS catalogs. Furthermore, by retaining stars below the brightness limit of current surveys we are able to provide better spatial coverage to help point or position the next generation of infrared telescopes.
- ID:
- ivo://CDS.VizieR/J/ApJ/639/227
- Title:
- MSX IRDC candidate catalog
- Short Name:
- J/ApJ/639/227
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use 8.3{mu}m mid-infrared images acquired with the Midcourse Space Experiment satellite to identify and catalog infrared dark clouds (IRDCs) in the first and fourth quadrants of the Galactic plane. Because IRDCs are seen as dark extinction features against the diffuse Galactic infrared background, we identify them by first determining a model background from the 8.3{mu}m images and then searching for regions of high decremental contrast with respect to this background. IRDC candidates in our catalog are defined by contiguous regions bounded by closed contours of a 2{sigma} decremental contrast threshold. We identify 10,931 candidate IRDCs. For each IRDC, we also catalog cores. These cores, defined as localized regions with at least 40% higher extinction than the cloud's average extinction, are found by iteratively fitting two-dimensional elliptical Gaussian functions to the contrast peaks. We identify 12,774 cores. The catalog contains the position, angular size, orientation, area, peak contrast, peak contrast signal-to-noise, and integrated contrast of the candidate IRDCs and their cores.
- ID:
- ivo://CDS.VizieR/J/AJ/126/1423
- Title:
- MSX 8.3um fluxes of star-forming regions
- Short Name:
- J/AJ/126/1423
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have imaged seven nearby star-forming regions, the Rosette Nebula, the Orion Nebula, W3, the Pleiades, G300.2-16.8, S263, and G159.6-18.5, with the Spatial Infrared Imaging Telescope on the Midcourse Space Experiment (MSX) satellite at 18" resolution at 8.3, 12.1, 14.7, and 21.3{mu}m. The large angular scale of the regions imaged (~7.2-50deg^2^) makes these data unique in terms of the combination of size and resolution. In addition to the star-forming regions, two cirrus-free fields (MSXBG 160 and MSXBG 161) and a field near the south Galactic pole (MSXBG 239) were also imaged. Point sources have been extracted from each region, resulting in the identification over 500 new sources (i.e., no identified counterparts at other wavelengths), as well as over 1300 with prior identifications. The extended emission from the star-forming regions is described, and prominent structures are identified, particularly in W3 and Orion. The Rosette Nebula is discussed in detail. The bulk of the mid-infrared emission is consistent with that of photon-dominated regions, including the elephant trunk complex. The central clump, however, and a line of site toward the northern edge of the cavity show significantly redder colors than the rest of the Rosette complex.
