- ID:
- ivo://CDS.VizieR/J/ApJ/835/280
- Title:
- WISE MIR properties of galaxies in compact groups
- Short Name:
- J/ApJ/835/280
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We study the mid-infrared (MIR) properties of galaxies in compact groups and their environmental dependence using the Wide-field Infrared Survey Explorer (WISE) data. We use a volume-limited sample of 670 compact groups and their 2175 member galaxies with M_r_<-19.77 and 0.01<z<0.0741, drawn from Sohn+ (2016, J/ApJS/225/23), which were identified using a friends-of-friends algorithm. Among the 2175 galaxies, 1541 galaxies are detected at WISE 12um with a signal-to-noise ratio greater than 3. Among the 1541 galaxies, 433 AGN-host galaxies are identified by using both optical and MIR classification schemes. Using the remaining 1108 non-AGN galaxies, we find that the MIR [3.4]-[12] colors of compact group early-type galaxies are on average bluer than those of cluster early-type galaxies. When compact groups have both early- and late-type member galaxies, the MIR colors of the late-type members in those compact groups are bluer than the MIR colors of cluster late-type galaxies. As compact groups are located in denser regions, they tend to have larger early-type galaxy fractions and bluer MIR color galaxies. These trends are also seen for neighboring galaxies around compact groups. However, compact group member galaxies always have larger early-type galaxy fractions and bluer MIR colors than their neighboring galaxies. Our findings suggest that the properties of compact group galaxies depend on both internal and external environments of compact groups, and that galaxy evolution is faster in compact groups than in the central regions of clusters.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/255/10
- Title:
- WISE MIR variability in gamma-ray Seyfert 1 gal.
- Short Name:
- J/ApJS/255/10
- Date:
- 11 Mar 2022
- Publisher:
- CDS
- Description:
- Fermi-LAT's detection of {gamma}-rays from narrow-line Seyfert 1 galaxies (NLS1s) has received increasing attention. Understanding these {gamma}-NLS1s is of interest because they have some properties similar to blazars, which are known to show rapid and large-amplitude variability. Based on the largest sample of {gamma}-NLS1s (25 sources), we carried out a systematic search for rapid mid-infrared (MIR, 3.4 and 4.6{mu}m) variability using the multiepoch data of the Wide-field Infrared Survey Explorer (WISE). We also compared a few variability properties between {gamma}-NLS1s and {gamma}-ray blazars. Our main results are as follows. (1) Thirteen {gamma}-NLS1s showed significant (>3{sigma}) rapid variability in at least one of the two MIR bands. The MIR emission of these sources is dominated by the synchrotron emission of relativistic electrons in the jet. (2) The {gamma}-NLS1s with flat radio spectra are more variable than those not detected in {gamma}-rays. (3) The {gamma}-NLS1s tend to show smaller amplitude of variability as well as lower duty cycle relative to {gamma}-ray blazars. (4) The {gamma}-NLS1s tend to show a trend of bluer-when-brighter on both intraday and long timescales, similar to {gamma}-ray blazars. (5) The {gamma}-NLS1s that are more variable on long timescales have larger amplitudes of variability and higher duty cycles on intraday timescales. (6) In the majority of cases, the {gamma}-NLS1s fall in the WISE Gamma-ray Blazar Strip (WGS). However, we noted migrations outside of the WGS due to significant variability.
- ID:
- ivo://CDS.VizieR/J/ApJ/797/55
- Title:
- WISE photometry of dust-free stellar systems
- Short Name:
- J/ApJ/797/55
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Using data from the Wide-field Infrared Survey Explorer mission, we have measured near infra-red (NIR) photometry of a diverse sample of dust-free stellar systems (globular clusters, dwarf and giant early-type galaxies) which have metallicities that span the range -2.2<[Fe/H](dex)<0.3.
- ID:
- ivo://CDS.VizieR/J/ApJ/792/129
- Title:
- WISE W1/W2 Tully-Fisher relation calibrator data
- Short Name:
- J/ApJ/792/129
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In order to explore local large-scale structures and velocity fields, accurate galaxy distance measures are needed. We now extend the well-tested recipe for calibrating the correlation between galaxy rotation rates and luminosities-capable of providing such distance measures-to the all-sky, space-based imaging data from the Wide-field Infrared Survey Explorer (WISE) W1 (3.4 {mu}m) and W2 (4.6 {mu}m) filters. We find a correlation of line width to absolute magnitude (known as the Tully-Fisher relation, TFR) of M_W1_^b,i,k,a^=-20.35-9.56(logW_mx_^i^-2.5) (0.54 mag rms) and M_W2_^b,i,k,a^=-19.76-9.74(logW_mx_^i^-2.5) (0.56 mag rms) from 310 galaxies in 13 clusters. We update the I-band TFR using a sample 9% larger than in Tully & Courtois (2012ApJ...749...78T). We derive M_l_^b,i,k^=-21.34-8.95(logW_mx_^i^-2.5) (0.46 mag rms). The WISE TFRs show evidence of curvature. Quadratic fits give M_W1_^b,i,k,a^=-20.48-8.36(logW_mx_^i^-2.5)+3.60(loglogW_mx_^i^-2.5)^2^ (0.52 mag rms) and M_W2_^b,i,k,a^=-19.91-8.40(logW_mx_^i^-2.5)+ 4.32(loglogW_mx_^i^ -2.5)^2^ (0.55 mag rms). We apply an I-band -WISE color correction to lower the scatter and derive M_Cw1_=-20.22-9.12(logW_mx_^i^-2.5) and M_Cw2_=-19.63-9.11(logW_mx_^i^-2.5) (both 0.46 mag rms). Using our three independent TFRs (W1 curved, W2 curved, and I band), we calibrate the UNION2 Type Ia supernova sample distance scale and derive H_0_=74.4+/-1.4(stat)+/-2.4(sys) km/s/Mpc with 4% total error.
- ID:
- ivo://CDS.VizieR/J/ApJS/182/625
- Title:
- WIYN spectroscopy in the deep SWIRE field
- Short Name:
- J/ApJS/182/625
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of spectroscopy using HYDRA on the WIYN 3.5m telescope of objects in the deep SWIRE radio field. The goal of the project was to determine spectroscopic redshifts for as many of the brighter objects in the field as possible, especially those detected in the radio and at 24um. These redshifts are primarily being used in studies of galaxy evolution and the connection of that evolution to active galactic nuclei and star formation. Redshifts measured for 365 individual objects are reported. The redshifts range from 0.03 to 2.5, mostly with z<0.9. The sources were selected to be within the WIYN HYDRA field of approximately 30' in radius from the center of the SWIRE deep field, 10:46:00, +59:01:00 (J2000). Optical sources for spectroscopic observation were selected from an r-band image of the field. A priority list of spectroscopic targets was established in the following order: 20cm detections, 24m detections, galaxies with r<20 and the balance made up of fainter galaxies in the field. We provide a table listing the galaxy positions, measured redshift and error, and note any emission lines that were visible in the spectrum. In practice, almost all the galaxies with r<19 were observed including all of the radio sources and most of the 24um sources with r<20 and a sample of radio sources which had fainter optical counterparts on the r-band image.
3746. WMAP3 catalogue
- ID:
- ivo://CDS.VizieR/J/A+A/508/107
- Title:
- WMAP3 catalogue
- Short Name:
- J/A+A/508/107
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an extensive search to identify the counterparts of all the microwave foreground sources listed in the WMAP 3-year catalogue using literature and archival data. Our work has led to the identification of 309 WMAP sources, 98% of which are blazars, radio quasars, or radio galaxies. Only 7 WMAP detections were identified with other types of cosmic sources (3 starburst galaxies and 4 planetary/LBN nebulae). At present, 15 objects (<5%) still remain without identification because of the unavailability of optical spectroscopic data or a clear radio counterpart. Our results allow us to define a flux-limited sample of 203 high Galactic latitude microwave sources (f_41GHz_>=1Jy, |b_II_|>15{deg} that is virtually completely identified (99%).
- ID:
- ivo://CDS.VizieR/J/ApJS/180/283
- Title:
- WMAP five-year source catalog
- Short Name:
- J/ApJS/180/283
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the list of point sources found in the Wilkinson Microwave Anisotropy Probe (WMAP) five-year maps. The technique used in the first-year and three-year analyses now finds 390 point sources, and the five-year source catalog is complete for regions of the sky away from the Galactic plane to a 2Jy limit, with SNR>4.7 in all bands in the least covered parts of the sky. The noise at high frequencies is still mainly radiometer noise, but at low frequencies the cosmic microwave background (CMB) anisotropy is the largest uncertainty. A separate search of CMB-free V-W maps finds 99 sources of which all but one can be identified with known radio sources. The sources seen by WMAP are not strongly polarized. Many of the WMAP sources show significant variability from year to year, with more than a 2:1 range between the minimum and maximum fluxes.
- ID:
- ivo://CDS.VizieR/J/AJ/146/162
- Title:
- Wolf-Rayet and RSG stars in M101. I. HST photometry
- Short Name:
- J/AJ/146/162
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Assembling a catalog of at least 10000 Wolf-Rayet (W-R) stars is an essential step in proving (or disproving) that these stars are the progenitors of Type Ib and Type Ic supernovae. To this end, we have used the Hubble Space Telescope (HST) to carry out a deep, HeII optical narrowband imaging survey of the ScI spiral galaxy M101. Almost the entire galaxy was imaged with the unprecedented depth and resolution that only the HST affords. Differenced with archival broadband images, the narrowband images allow us to detect much of the W-R star population of M101. We describe the extent of the survey and our images, as well as our data reduction procedures. A detailed broadband-narrowband imaging study of a field east of the center of M101, containing the giant star-forming region NGC5462, demonstrates our completeness limits, how we find W-R candidates, their properties and spatial distribution, and how we rule out most contaminants. We use the broadband images to locate luminous red supergiant (RSG) candidates. The spatial distributions of the W-R and RSG stars near NGC 5462 are strikingly different. W-R stars dominate the complex core, while RSGs dominate the complex halo. Future papers in this series will describe and catalog more than a thousand W-R and RSG candidates that are detectable in our images, as well as spectra of many of those candidates.
- ID:
- ivo://CDS.VizieR/J/ApJ/759/11
- Title:
- Wolf-Rayet content of M31
- Short Name:
- J/ApJ/759/11
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Wolf-Rayet (WR) stars are evolved massive stars, and the relative number of WC-type and WN-type WRs should vary with the metallicity of the host galaxy, providing a sensitive test of stellar evolutionary theory. However, past studies of the WR content of M31 have been biased toward detecting WC stars, as their emission-line signatures are much stronger than those of WNs. Here, we present the results of a survey covering all of M31's optical disk (2.2deg^2^), with sufficient sensitivity to detect the weaker-lined WN types. We identify 107 newly found WR stars, mostly of WN type. This brings the total number of spectroscopically confirmed WRs in M31 to 154, a number we argue is complete to ~95%, except in regions of unusually high reddening. This number is consistent with what we expect from the integrated H{alpha} luminosity compared to that of M33. The majority of these WRs formed in OB associations around the Population I ring, although 5% are truly isolated. Both the relative number of WC- to WN-type stars as well as the WC subtype distribution suggest that most WRs exist in environments with higher-than-solar metallicities, which is consistent with studies of M31's metallicity. Although the WC to WN ratio we find for M31 is much lower than that found by previous studies, it is still higher than what the Geneva evolutionary models predict. This may suggest that Roche-lobe overflow produces the excess of WC stars observed at high metallicity, or that the assumed rotational velocities in the models are too high.
- ID:
- ivo://CDS.VizieR/J/ApJ/655/851
- Title:
- Wolf-Rayet galaxies in the SDSS
- Short Name:
- J/ApJ/655/851
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We use a large sample of 174 Wolf-Rayet (W-R) galaxies drawn from the Sloan Digital Sky Survey to study whether and how the slope of the stellar initial mass function depends on metallicity. We calculate for each object its oxygen abundance, according to which we divide our sample into four metallicity subsamples. For each subsample, we then measure three quantities: the equivalent width of the H{beta} emission line, the equivalent width of the W-R bump around 4650{AA}, and the W-R bump-to-Hbeta intensity ratio, and compare to the predictions of the same quantities by evolutionary synthesis models of Schaerer & Vacca (1998ApJ...497..618S).
