- ID:
- ivo://CDS.VizieR/J/AJ/162/140
- Title:
- The SOS. VII. UBVI photometry of open cluster IC 1590
- Short Name:
- J/AJ/162/140
- Date:
- 21 Mar 2022 00:39:36
- Publisher:
- CDS
- Description:
- Young open clusters are ideal laboratories to understand the star formation process. We present deep UBVI and H{alpha} photometry for the young open cluster IC1590 in the center of the HII region NGC281. Early-type members are selected from UBV photometric diagrams, and low-mass pre-main-sequence (PMS) members are identified by using H{alpha} photometry. In addition, the published X-ray source list and Gaia astrometric data are also used to isolate probable members. A total of 408 stars are selected as members. The mean reddening obtained from early-type members is <E(B-V)>=0.40{+/-}0.06(s.d.). We confirm the abnormal extinction law for the intracluster medium. The distance modulus to the cluster determined from the zero-age main-sequence fitting method is 12.3{+/-}0.2mag (d=2.88{+/-}0.28kpc), which is consistent with the distance d=2.70_-0.20_^+0.24^kpc from the recent Gaia parallaxes. We also estimate the ages and masses of individual members by means of stellar evolutionary models. The mode of the age of PMS stars is about 0.8Myr. The initial mass function of IC1590 is derived. It appears to be a steeper shape ({Gamma}=-1.49{+/-}0.14) than that of the Salpeter/Kroupa initial mass function for the high-mass regime (m>1M{sun}). The signature of mass segregation is detected from the difference in the slopes of the initial mass functions for the inner (r<2.5') and outer regions of this cluster. We finally discuss the star formation history in NGC281.
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- ID:
- ivo://CDS.VizieR/J/AJ/150/40
- Title:
- The Spitzer c2d survey of clouds. XII. Perseus
- Short Name:
- J/AJ/150/40
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Spitzer Space Telescope mapped the Perseus molecular cloud complex with the Infrared Array Camera (IRAC) and the Multi-Band Imaging Photometer for Spitzer (MIPS) as part of the c2d Spitzer Legacy project. This paper combines the observations from both instruments giving an overview of low-mass star formation across Perseus from 3.6 to 70{mu}m. We provide an updated list of young stellar objects (YSOs) with new classifications and source fluxes from previous works, identifying 369 YSOs in Perseus with the Spitzer data set. By synthesizing the IRAC and MIPS maps of Perseus and building on the work of previous papers in this series, we present a current census of star formation across the cloud and within smaller regions. Sixty-seven percent of the YSOs are associated with the young clusters NGC 1333 and IC 348. The majority of the star formation activity in Perseus occurs in the regions around the clusters to the eastern and western ends of the cloud complex. The middle of the cloud is nearly empty of YSOs despite containing regions of high visual extinction. The western half of Perseus contains three-quarters of the total number of embedded YSOs (Class 0+I and Flat spectral energy distribution sources) in the cloud and nearly as many embedded YSOs as Class II and III sources. Class II and III objects greatly outnumber Class 0+I objects in eastern Perseus and IC 348. These results are consistent with previous age estimates for the clusters. Across the cloud, 56% of YSOs and 91% of the Class 0+I and Flat sources are in areas where A_v_>=5mag, indicating a possible extinction threshold for star formation.
- ID:
- ivo://CDS.VizieR/J/ApJ/724/835
- Title:
- The Spitzer c2d survey of WTTSs. III.
- Short Name:
- J/ApJ/724/835
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present 3.6 to 70um Spitzer photometry of 154 weak-line T Tauri stars (WTTSs) in the Chamaeleon, Lupus, Ophiuchus, and Taurus star formation regions, all of which are within 200pc of the Sun. For a comparative study, we also include 33 classical T Tauri stars which are located in the same star-forming regions. Spitzer sensitivities allow us to robustly detect the photosphere in the IRAC bands (3.6 to 8um) and the 24um MIPS band. In the 70um MIPS band, we are able to detect dust emission brighter than roughly 40 times the photosphere. These observations represent the most sensitive WTTSs survey in the mid- to far-infrared to date and reveal the frequency of outer disks (r=3-50AU) around WTTSs. The 70um photometry for half the c2d WTTSs sample (the on-cloud objects), which were not included in the earlier papers in this series, those of Padgett et al. (2006ApJ...645.1283P) and Cieza et al. (2007, Cat. J/ApJ/667/308) are presented here for the first time.
- ID:
- ivo://CDS.VizieR/J/ApJ/701/428
- Title:
- The Spitzer Deep, Wide-Field Survey (SDWFS)
- Short Name:
- J/ApJ/701/428
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Spitzer Deep, Wide-Field Survey (SDWFS) is a four-epoch infrared survey of 10deg^2^ in the Bootes field of the NOAO Deep Wide-Field Survey using the IRAC instrument on the Spitzer Space Telescope. SDWFS, a Spitzer Cycle 4 Legacy project, occupies a unique position in the area-depth survey space defined by other Spitzer surveys. The four epochs that make up SDWFS permit-for the first time-the selection of infrared-variable and high proper motion objects over a wide field on timescales of years. Because of its large survey volume, SDWFS is sensitive to galaxies out to z~3 with relatively little impact from cosmic variance for all but the richest systems. The SDWFS data sets will thus be especially useful for characterizing galaxy evolution beyond z~1.5. This paper explains the SDWFS observing strategy and data processing, presents the SDWFS mosaics and source catalogs, and discusses some early scientific findings. The publicly released, full-depth catalogs contain 6.78, 5.23, 1.20, and 0.96x10^5^ distinct sources detected to the average 5{sigma}, 4"-diameter, aperture-corrected limits of 19.77, 18.83, 16.50, and 15.82 Vega mag at 3.6, 4.5, 5.8, and 8.0um, respectively. The SDWFS number counts and color-color distribution are consistent with other, earlier Spitzer surveys. At the 6 minute integration time of the SDWFS IRAC imaging, >50% of isolated Faint Images of the Radio Sky at Twenty cm radio sources and >80% of on-axis XBootes sources are detected out to 8.0um. Finally, we present the four highest proper motion IRAC-selected sources identified from the multi-epoch imaging, two of which are likely field brown dwarfs of mid-T spectral class.
- ID:
- ivo://CDS.VizieR/J/ApJS/254/11
- Title:
- The Spitzer Kepler Survey (SpiKeS) catalog
- Short Name:
- J/ApJS/254/11
- Date:
- 17 Jan 2022 00:38:57
- Publisher:
- CDS
- Description:
- The ~200000 targets monitored for photometric variability during the Kepler prime mission include the best-studied group of stars in the sky, due both to the extensive time history provided by Kepler and to the substantial amount of ancillary data provided by other investigators or compiled by the Kepler team. To complement this wealth of data, we surveyed the entire Kepler field using the 3.6 and 4.5{mu}m bands of the Warm Spitzer Space Telescope, obtaining photometry in both bands for almost 170000 objects. We demonstrate relative photometric precision ranging from better than ~1.5% for the brighter stars down to slightly greater than ~2% for the faintest stars monitored by Kepler. We describe the data collection and analysis phases of this work and identify several stars with large infrared excess, although none that is also known to be the host of an exoplanetary system.
- ID:
- ivo://CDS.VizieR/J/ApJ/703/517
- Title:
- The Spitzer Local Volume Legacy: IR photometry
- Short Name:
- J/ApJ/703/517
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The survey description and the near-, mid-, and far-infrared flux properties are presented for the 258 galaxies in the Local Volume Legacy (LVL). LVL is a Spitzer Space Telescope legacy program that surveys the local universe out to 11Mpc, built upon a foundation of ultraviolet, H{alpha}, and Hubble Space Telescope imaging from 11HUGS (11Mpc H{alpha} and Ultraviolet Galaxy Survey, Cat. J/ApJS/178/247) and ANGST (ACS Nearby Galaxy Survey Treasury, 2009ApJS..183...67D). LVL covers an unbiased, representative, and statistically robust sample of nearby star-forming galaxies, exploiting the highest extragalactic spatial resolution achievable with Spitzer.
- ID:
- ivo://CDS.VizieR/J/ApJ/741/79
- Title:
- The Spitzer-SDSS-GALEX Spectroscopic Survey
- Short Name:
- J/ApJ/741/79
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The Spitzer-SDSS-GALEX Spectroscopic Survey (SSGSS) provides a new sample of 101 star-forming galaxies at z<0.2 with unprecedented multi-wavelength coverage. New mid- to far-infrared spectroscopy from the Spitzer Space Telescope is added to a rich suite of previous imaging and spectroscopy, including ROSAT, Galaxy Evolution Explorer, Sloan Digital Sky Survey, Two Micron All Sky Survey, and Spitzer/SWIRE. Sample selection ensures an even coverage of the full range of normal galaxy properties, spanning two orders of magnitude in stellar mass, color, and dust attenuation. In this paper we present the SSGSS data set, describe the science drivers, and detail the sample selection, observations, data reduction, and quality assessment.
- ID:
- ivo://CDS.VizieR/II/368
- Title:
- The Spitzer (SEIP) source list (SSTSL2)
- Short Name:
- II/368
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- The Spitzer Science Center and IRSA have released a set of Enhanced Imaging Products (SEIP) from the Spitzer Heritage Archive. These include Super Mosaics and a Source List (SL) of photometry for compact sources. The primary requirement on the Source List is very high reliability -- with areal coverage, completeness, and limiting depth being secondary considerations. The SEIP include data from the four channels of IRAC (3.6, 4.5, 5.8, 8 microns) and the 24 micron channel of MIPS. The full set of products for the Spitzer cryogenic mission includes around 42 million sources.
- ID:
- ivo://CDS.VizieR/J/ApJ/900/55
- Title:
- The SPT-SZ catalog at 95, 150, and 220GHz
- Short Name:
- J/ApJ/900/55
- Date:
- 21 Mar 2022 09:29:14
- Publisher:
- CDS
- Description:
- We present a catalog of emissive point sources detected in the SPT-SZ survey, a contiguous 2530 square degree area surveyed with the South Pole Telescope (SPT) from 2008-2011 in three bands centered at 95, 150, and 220GHz. The catalog contains 4845 sources measured at a significance of 4.5{sigma} or greater in at least one band, corresponding to detections above approximately 9.8, 5.8, and 20.4mJy in 95, 150, and 220GHz, respectively. The spectral behavior in the SPT bands is used for source classification into two populations based on the underlying physical mechanisms of compact, emissive sources that are bright at millimeter wavelengths: synchrotron radiation from active galactic nuclei and thermal emission from dust. The latter population includes a component of high-redshift sources often referred to as submillimeter galaxies (SMGs). In the relatively bright flux ranges probed by the survey, these sources are expected to be magnified by strong gravitational lensing. The survey also contains sources consistent with protoclusters, groups of dusty galaxies at high redshift undergoing collapse. We cross-match the SPT-SZ catalog with external catalogs at radio, infrared, and X-ray wavelengths and identify available redshift information. The catalog splits into 3980 synchrotron-dominated and 865 dust-dominated sources, and we determine a list of 506 SMGs. Ten sources in the catalog are identified as stars. We calculate number counts for the full catalog, and synchrotron and dusty components, using a bootstrap method and compare our measured counts with models. This paper represents the third and final catalog of point sources in the SPT-SZ survey.
6820. The SSRS2 Sample
- ID:
- ivo://CDS.VizieR/J/AJ/108/1987
- Title:
- The SSRS2 Sample
- Short Name:
- J/AJ/108/1987
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we continue our investigation on the isophotal nature, accuracy, and uniformity of the magnitude system adopted in the Southern Sky Redshift Survey extension (SSRS2). Extending our earlier work, we examine galaxies in the equatorial region, primarily in the declination range -17.5 deg <= Dec. <= 0 deg, over a large range of right ascension, covering the southern and northern Galactic caps. For this purpose, we have obtained CCD isophotal magnitudes in the B and R bands for 265 galaxies of different morphological types. Using this larger sample we confirm our earlier claim that the m(SSRS2) magnitudes are very nearly the magnitude measured within the isophote mu_B = 26 mag/arcsec^2, with a dispersion of about 0.30 mag. The relative zero-point offset between our m(SSRS2) magnitudes and CCD photometry is -0.02 mag from all data we have obtained. However, we detect a variation of the zero-point across different regions of the sky of +/- 0.10 mag for regions at large angular separations. We also estimate that the zero-point offset between the m(SSRS2) and Zwicky systems is relatively small (~0.10 mag), which should allow us to combine the data from the SSRS2 and the CfA2 Redshift Survey.
