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Start Over Subject infrared astronomy
1181. Tycho-2 stars with IR excess
ID:
ivo://CDS.VizieR/J/MNRAS/363/1111
Title:
Tycho-2 stars with IR excess
Short Name:
J/MNRAS/363/1111
Date:
21 Oct 2021
Publisher:
CDS
Description:
Stars of all evolutionary phases have been found to have excess infrared emission due to the presence of circumstellar material. To identify such stars, we have positionally correlated the infrared Mid-Course Space Experiment (MSX) Point Source Catalogue (<V/114>) and the Tycho-2 optical catalogue (<I/259>). Near-mid-infrared colour criteria have been developed to select infrared excess stars. The search yielded 1938 excess stars; over half (979) have never previously been detected by IRAS. The excess stars were found to be young objects such as Herbig Ae/Be and Be stars, and evolved objects such as OH/IR (infrared) and carbon stars. A number of B-type excess stars were also discovered whose infrared colours could not be readily explained by known catalogued objects.
1182. Type 1 vs 2 X-ray-selected COSMOS AGNs & environment
ID:
ivo://CDS.VizieR/J/ApJ/878/11
Title:
Type 1 vs 2 X-ray-selected COSMOS AGNs & environment
Short Name:
J/ApJ/878/11
Date:
21 Oct 2021
Publisher:
CDS
Description:
The unified model of active galactic nuclei (AGNs) proposes that different AGN optical spectral types are caused by different viewing angles with respect to an obscuring "torus". Therefore, this model predicts that type 1 and type 2 AGNs should have similar host-galaxy properties. We investigate this prediction with 2463 X-ray-selected AGNs in the COSMOS field. We divide our sample into type 1 and type 2 AGNs based on their spectra, morphologies, and variability. We derive their host-galaxy stellar masses (M_*_) through spectral energy distribution (SED) fitting, and we find that the hosts M_*_ of type 1 AGNs tend to be slightly smaller than those of type 2 AGNs by {Delta}logM_*_~0.2dex (~4{sigma} significance). Besides deriving star formation rates (SFRs) from SED fitting, we also utilize far-infrared (FIR) photometry and a stacking method to obtain FIR-based SFRs. We find that the SFRs of type 1 and type 2 sources are similar once their redshifts and X-ray luminosities are controlled. We also investigate the cosmic environment, and we find that the surface number densities (sub-Mpc) and cosmic-web environments (~1-10Mpc) are similar for both populations. In summary, our analyses show that the host galaxies of type 1 and type 2 AGNs have similar SFRs and cosmic environments in general, but the former tend to have a lower M_*_ than the latter. The difference in M_*_ indicates that the AGN unification model is not strictly correct, and both host galaxy and torus may contribute to the optical obscuration of AGNs.
1183. UBV light curves of V354 Lac
ID:
ivo://CDS.VizieR/J/other/PZ/29.1
Title:
UBV light curves of V354 Lac
Short Name:
J/other/PZ/29.1
Date:
21 Oct 2021
Publisher:
CDS
Description:
New photometry obtained in 2000-2008 is presented for the post-AGB star IRAS 22272+5435 = V354 Lac. The star showed semi-regular light variations with varying amplitudes.
1184. UBV photometry of IRAS 18062+2410
ID:
ivo://CDS.VizieR/J/PAZh/25/30
Title:
UBV photometry of IRAS 18062+2410
Short Name:
J/PAZh/25/30
Date:
21 Oct 2021
Publisher:
CDS
Description:
The photometric and spectroscopic observations of IRAS 18062+2410 = V886 Her, a candidate for protoplanetary objects, in 1996-1997 are presented. The star exhibits rapid light variations with an amplitude up to 0.3mag in V. A high-resolution spectrum of IRAS shows absorption lines of H, HeI, OI, FeII, SiII, NaI and other species, including [OII], [NII], and [FeII] that belong to the stellar envelope.
1185. UKIDSS-DR6 Galactic Plane Survey
ID:
ivo://CDS.VizieR/II/316
Title:
UKIDSS-DR6 Galactic Plane Survey
Short Name:
II/316
Date:
21 Oct 2021
Publisher:
CDS
Description:
The UKIDSS Galactic Plane Survey (GPS) is one of the five near infrared Public Legacy Surveys that are being undertaken by the UKIDSS consortium, using the Wide Field Camera on the United Kingdom Infrared Telescope. It is surveying 1868 deg^2^ of the northern and equatorial Galactic plane at Galactic latitudes -5{deg}<b<5{deg} in the J, H and K filters and a ~300 deg^2^ area of the Taurus-Auriga-Perseus molecular cloud complex in these three filters and the 2.12{mu}m (1-0)S(1)H_2_ filter. It will provide data on ~ 3x10^9^ sources. The survey use the Wide Field Camera (WFCAM, see Casali et al. 2007A&A...467..777C) on the United Kingdom Infrared Telescope (UKIRT). The typical 90% completeness limits in uncrowded fields are K=18.0, H=18.75, J=19.5, with uncertainties of about 0.2mag.
1186. UKIDSS-DR7 Large Area Survey
ID:
ivo://CDS.VizieR/II/310
Title:
UKIDSS-DR7 Large Area Survey
Short Name:
II/310
Date:
21 Oct 2021
Publisher:
CDS
Description:
The UKIRT Infrared Deep Sky Survey (UKIDSS) is a large-scale near-IR survey which aim is to cover 7500 square degrees of the Northern sky. The survey is carried out using the Wide Field Camera (WFCAM), with a field of view of 0.21 square degrees, mounted on the 3.8m United Kingdom Infra-red Telescope (UKIRT) in Hawaii. The Large Area Survey (LAS) covers an area of 4000 square degrees in high Galactic latitudes (extragalactic) in the four bands Y(1.0um) J(1.2um) H(1.6um) and K(2.2um) to a depth of K = 18.4. Details of the survey can be found in the in the paper by Lawrence et al. (2007MNRAS.379.1599L)
1187. UKIDSS-DR9 LAS, GCS and DXS Surveys
ID:
ivo://CDS.VizieR/II/319
Title:
UKIDSS-DR9 LAS, GCS and DXS Surveys
Short Name:
II/319
Date:
21 Oct 2021
Publisher:
CDS
Description:
The UKIRT Infrared Deep Sky Survey (UKIDSS) is a large-scale near-IR survey which aim is to cover 7500 square degrees of the Northern sky. The survey is carried out using the Wide Field Camera (WFCAM), with a field of view of 0.21 square degrees, mounted on the 3.8m United Kingdom Infra-red Telescope (UKIRT) in Hawaii. The project comprises five surveys (LAS, GCS, DXS, GPS and UDS). The Large Area Survey (LAS) covers an area of 4000 square degrees in high Galactic latitudes (extragalactic) in the four bands Y(1.0um) J(1.2um) H(1.6um) and K(2.2um) to a depth of K=18.4. This release 9 includes proper motions for a fraction (~1/6) of the sources. The Galactic Clusters Survey (GCS) aims to survey ten large open star clusters and star formation associations, covering a total of 1067 square degrees in the five bands Z (0.9um), Y(1.0um) J(1.2um) H(1.6um) and K(2.2um), plus a second pass in K for proper motions, to a depth of Z=20.4, Y=20.3, J=19.5, H=18.6, K=18.6. This release 9 includes proper motions for a fraction (~1/4) of the sources. The Deep Extragalactic Survey (DXS) aims to map 35 square degrees of sky to a 5-{sigma} point-source sensitivity of J=22.3 and K=20.8 in four carefully selected, multi-wavelength survey areas. The central regions of each field will also be mapped to H=21.8. The primary aim of the survey is to produce a photometric galaxy sample at a redshift of 1-2, within a volume comparable to that of the SDSS, selected in the same passband (rest frame optical). Details of the surveys can be found in the in the paper by Lawrence et al. (2007MNRAS.379.1599L), and at the UKIDSS Surveys site (http://www.ukidss.org/surveys/surveys.html). The data described here represent a subset of the UKIDSS data, limited to the public data and most representative columns. In the "Byte-by-byte Description" below the original names of the columns are given as bracketed names.
1188. UKIDSS-DR8 LAS, GCS and DXS Surveys
ID:
ivo://CDS.VizieR/II/314
Title:
UKIDSS-DR8 LAS, GCS and DXS Surveys
Short Name:
II/314
Date:
21 Oct 2021
Publisher:
CDS
Description:
The UKIRT Infrared Deep Sky Survey (UKIDSS) is a large-scale near-IR survey which aim is to cover 7500 square degrees of the Northern sky. The survey is carried out using the Wide Field Camera (WFCAM), with a field of view of 0.21 square degrees, mounted on the 3.8m United Kingdom Infra-red Telescope (UKIRT) in Hawaii. The project comprises five surveys (LAS, GCS, DXS, GPS and UDS). The Large Area Survey (LAS) covers an area of 4000 square degrees in high Galactic latitudes (extragalactic) in the four bands Y(1.0um) J(1.2um) H(1.6um) and K(2.2um) to a depth of K=18.4. The Galactic Clusters Survey (GCS) aims to survey ten large open star clusters and star formation associations, covering a total of 1067 square degrees in the five bands Z (0.9um), Y(1.0um) J(1.2um) H(1.6um) and K(2.2um), plus a second pass in K for proper motions, to a depth of Z=20.4, Y=20.3, J=19.5, H=18.6, K=18.6. The Deep Extragalactic Survey (DXS) aims to map 35 square degrees of sky to a 5-{sigma} point-source sensitivity of J=22.3 and K=20.8 in four carefully selected, multi-wavelength survey areas. The central regions of each field will also be mapped to H=21.8. The primary aim of the survey is to produce a photometric galaxy sample at a redshift of 1-2, within a volume comparable to that of the SDSS, selected in the same passband (rest frame optical). Details of the surveys can be found in the in the paper by Lawrence et al. (2007MNRAS.379.1599L), and at the UKIDSS Surveys site (http://www.ukidss.org/surveys/surveys.html). The data described here represent a subset of the UKIDSS data, limited to the public data and most representative columns. In the "Byte-by-byte Description" below the original names of the columns are given as bracketed names.
1189. UKIDSS-2MASS proper motion survey
ID:
ivo://CDS.VizieR/J/MNRAS/394/857
Title:
UKIDSS-2MASS proper motion survey
Short Name:
J/MNRAS/394/857
Date:
21 Oct 2021
Publisher:
CDS
Description:
The UK Infrared Telescope Infrared Deep Sky Survey (UKIDSS) is the first of a new generation of infrared surveys. Here, we combine the data from two UKIDSS components, the Large Area Survey (LAS) and the Galactic Cluster Survey (GCS), with Two-Micron All-Sky Survey (2MASS) data to produce an infrared proper motion survey for low-mass stars and brown dwarfs. In total, we detect 267 low-mass stars and brown dwarfs with significant proper motions. We recover all 10 known single L dwarfs and the one known T dwarf above the 2MASS detection limit in our LAS survey area and identify eight additional new candidate L dwarfs. We also find one new candidate L dwarf in our GCS sample. Our sample also contains objects from 11 potential common proper motion binaries. Finally, we test our proper motions and find that while the LAS objects have proper motions consistent with absolute proper motions, the GCS stars may have proper motions which are significantly underestimated. This is possibly due to the bulk motion of some of the local astrometric reference stars used in the proper motion determination.
1190. Ultra-cool dwarfs at low Galactic latitudes
ID:
ivo://CDS.VizieR/J/MNRAS/427/3280
Title:
Ultra-cool dwarfs at low Galactic latitudes
Short Name:
J/MNRAS/427/3280
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an ultra-cool dwarf (UCD) catalogue compiled from low southern Galactic latitudes and mid-plane, from a cross-correlation of the Two Micron All-Sky Survey (2MASS) and the SuperCOSMOS survey. The catalogue contains 246 members identified from 5042deg^2^ within 220{deg}<=l<=360{deg} and 0{deg}<l<=30{deg}, for |b|<=15{deg}. Sixteen candidates are spectroscopically confirmed in the near-infrared as UCDs with spectral types from M7.5V to L9, the latest being the unusual blue L dwarf 2MASSJ11263991-5003550. Our catalogue selection method is presented enabling UCDs from ~M8V to the L-T transition to be selected down to a 2MASS limiting magnitude of Ks=~14.5mag (for S/N>=10).