- ID:
- ivo://CDS.VizieR/J/ApJS/100/105
- Title:
- Stellar velocity dispersions. II.
- Short Name:
- J/ApJS/100/105
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A catalog of central velocity dispersion measurements is presented, current through 1993 September. The catalog includes 2474 measurements of 1563 (*) galaxies. A standard set of 86 galaxies is defined, consisting of galaxies with at least three reliable concordant measurements. It is suggested that future studies observe some of these standard galaxies so that different studies can be normalised to a consistent system. All measurements are reduced to a normalized system using these standards. (*) Actually 1562 galaxies.
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Search Results
- ID:
- ivo://CDS.VizieR/J/ApJS/146/209
- Title:
- STIS emission-line galaxies observations
- Short Name:
- J/ApJS/146/209
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In the first 3 years of operation the Space Telescope Imaging Spectrograph (STIS) obtained slitless spectra of ~2500 fields in parallel to prime Hubble Space Telescope (HST) observations as part of the STIS parallel survey (SPS). The archive contains ~300 fields at high Galactic latitude (|b|>30{deg}) with spectroscopic exposure times greater than 3000s. This sample contains 219 fields (excluding special regions and requiring a consistent grating angle) observed between 1997 June 6 and 2000 September 21, with a total survey area of ~160-arcmin^2^. At this depth, the SPS detects an average of one emission-line galaxy per three fields. We present the analysis of these data and the identification of 131 low- to intermediate-redshift galaxies detected by optical emission lines. The sample contains 78 objects with emission lines that we infer to be redshifted [O II] {lambda}3727 emission at 0.43<z<1.7. The comoving number density of these objects is comparable to that of H{alpha}-emitting galaxies in the NICMOS parallel observations. One quasar and three probable Seyfert galaxies are detected. Many of the emission-line objects show morphologies suggestive of mergers or interactions. The reduced data are available upon request from the authors.
- ID:
- ivo://CDS.VizieR/J/MNRAS/478/1442
- Title:
- 78 Stripe82 galaxies masses
- Short Name:
- J/MNRAS/478/1442
- Date:
- 19 Jan 2022 11:53:49
- Publisher:
- CDS
- Description:
- We present a cross-calibration of CO- and dust-based molecular gas masses at z<=0.2. Our results are based on a survey with the IRAM 30-m telescope collecting CO(1-0) measurements of 78 massive (logM*/M_{sun}_>10) galaxies with known gas-phase metallicities and with IR photometric coverage from Wide-field Infrared Survey Explorer(WISE; 22um) and Herschel Spectral and Photometric Imaging Receiver (SPIRE; 250, 350, 500um). We find a tight relation (~0.17dex scatter) between the gas masses inferred from CO and dust continuum emission, with a minor systematic offset of 0.05dex. The two methods can be brought into agreement by applying a metallicity-dependent adjustment factor (~0.13dex scatter). We illustrate that the observed offset is consistent with a scenario in which dust traces not only molecular gas but also part of the HI reservoir, residing in the H_2_-dominated region of the galaxy. Observations of the CO(2-1) to CO(1-0) line ratio for two-thirds of the sample indicate a narrow range in excitation properties, with a median ratio of luminosities <R_21_>~0.64. Finally, we find dynamical mass constraints from spectral line profile fitting to agree well with the anticipated mass budget enclosed within an effective radius, once all mass components (stars, gas, and dark matter) are accounted for.
- ID:
- ivo://org.gavo.dc/annisred/q/cone
- Title:
- Stripe 82 Photometric Redshifts from SDSS Coadditions
- Short Name:
- s82 coadd cone
- Date:
- 27 Dec 2024 08:31:03
- Publisher:
- The GAVO DC team
- Description:
- This survey gives photometric redshifts of objects within 275 deg² (−50◦ < α < 60◦ and −1.◦25 < δ < +1.◦25) centered on the Celestial Equator. Each piece of sky has ∼20 runs of repeated scanning by the SDSS camera contributing and thus reaches ∼2 mag fainter than the SDSS single pass data, i.e., to r ∼ 23.5 for galaxies.
- ID:
- ivo://CDS.VizieR/J/ApJ/850/66
- Title:
- Stripe 82X survey multiwavelength catalog
- Short Name:
- J/ApJ/850/66
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Multiwavelength surveys covering large sky volumes are necessary to obtain an accurate census of rare objects such as high-luminosity and/or high-redshift active galactic nuclei (AGNs). Stripe 82X is a 31.3 X-ray survey with Chandra and XMM-Newton observations overlapping the legacy Sloan Digital Sky Survey Stripe 82 field, which has a rich investment of multiwavelength coverage from the ultraviolet to the radio. The wide-area nature of this survey presents new challenges for photometric redshifts for AGNs compared to previous work on narrow-deep fields because it probes different populations of objects that need to be identified and represented in the library of templates. Here we present an updated X-ray plus multiwavelength matched catalog, including Spitzer counterparts, and estimated photometric redshifts for 5961 (96% of a total of 6181) X-ray sources that have a normalized median absolute deviation, {sigma}_nmad_=0.06, and an outlier fraction, {eta}=13.7%. The populations found in this survey and the template libraries used for photometric redshifts provide important guiding principles for upcoming large-area surveys such as eROSITA and 3XMM (in X-ray) and the Large Synoptic Survey Telescope (optical).
- ID:
- ivo://CDS.VizieR/J/A+A/465/357
- Title:
- Stroemgren photometry in the Draco dSph galaxy
- Short Name:
- J/A+A/465/357
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we demonstrate how Stroemgren uvby photometry can be efficiently used to: 1. identify red giant branch stars that are members in a dwarf spheroidal galaxy; 2. derive age-independent metallicities for the same stars and quantify the associated errors. Stroemgren uvby photometry in a 11'x22' field centered on the Draco dwarf spheroidal galaxy was obtained using the Isaac Newton Telescope on La Palma. Members of the Draco dSph galaxy were identified using the surface gravity sensitive c1 index which discriminates between red giant and dwarf stars. Thus enabling us to distinguish the (red giant branch) members of the dwarf spheroidal galaxy from the foreground dwarf stars in our galaxy. The method is evaluated through a comparison of our membership list with membership classifications in the literature based on radial velocities and proper motions. The metallicity sensitive m1 index was used to derive individual and age-independent metallicities for the members of the Draco dSph galaxy. The derived metallicities are compared to studies based on high resolution spectroscopy and the agreement is found to be very good.
- ID:
- ivo://CDS.VizieR/J/MNRAS/439/788
- Title:
- Stromgren and Washington photometry in Boo I
- Short Name:
- J/MNRAS/439/788
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present new Stromgren and Washington data sets for the Bootes I dwarf galaxy, and combine them with the available Sloan Digital Sky Survey photometry. The goal of this project is to refine a ground-based, practical, accurate method to determine age and metallicity for individual stars in Bootes I that can be selected in an unbiased imaging survey, without having to take spectra. With few bright upper red giant branch stars and distances of about 35-250kpc, the ultra-faint dwarf galaxies (UDFs) present observational challenges in characterizing their stellar population. Other recent studies have produced spectra and proper motions, making Bootes I an ideal test case for our photometric methods. We produce photometric metallicities from Stromgren and Washington photometry, for stellar systems with a range of -1.0>[Fe/H]>-3.5. Needing to avoid the collapse of the metallicity sensitivity of the Stromgren m1-index on the lower red giant branch, we replace the Stromgren v filter with the broader Washington C filter to minimize observing time. We construct two indices: m*=(C-T1)0-(T1-T2)0 and m**=(C-b)0-(b-y)0. We find that CT1by is the most successful filter combination, for individual stars with [Fe/H] < -2.0, to maintain ~0.2dex [Fe/H]-resolution over the whole red giant branch. The m**-index would be the best choice for space-based observations because the (C-y) colour is not sufficient to fix metallicity alone in an understudied system. Our photometric metallicites of stars in the central regions of Bootes I confirm that there is a metallicity spread of at least -1.9>[Fe/H]>-3.7. The best-fitting Dartmouth isochrones give a mean age, for all the Bootes I stars in our data set, of 11.5+/-0.4Gyr. From ground-based telescopes, we show that the optimal filter combination is CT1by, avoiding the v filter entirely. We demonstrate that we can break the isochrones' age-metallicity degeneracy with the CT1by filters, using stars with logg=2.5-3.0, which have less than a 2percent change in their (C-T1) colour due to age, over a range of 10^-14^Gyr.
- ID:
- ivo://CDS.VizieR/J/ApJ/757/22
- Title:
- Strong and weak lensing analysis of A2261
- Short Name:
- J/ApJ/757/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We precisely constrain the inner mass profile of A2261 (z=0.225) for the first time and determine that this cluster is not "overconcentrated" as found previously, implying a formation time in agreement with {Lambda}CDM expectations. These results are based on multiple strong-lensing analyses of new 16-band Hubble Space Telescope imaging obtained as part of the Cluster Lensing and Supernova survey with Hubble (CLASH; Postman et al. 2012, Cat. J/ApJS/199/25). Combining this with revised weak-lensing analyses of Subaru wide-field imaging with five-band Subaru + KPNO photometry, we place tight new constraints on the halo virial mass M_vir_=(2.2+/-0.2)x10^15^M_{sun}_h^-1^_70_ (within r_vir_{approx}3Mpc.h^-1^_70_) and concentration c_vir_=6.2+/-0.3 when assuming a spherical halo. This agrees broadly with average c(M, z) predictions from recent {Lambda}CDM simulations, which span 5<~<c><~8. Our most significant systematic uncertainty is halo elongation along the line of sight (LOS). To estimate this, we also derive a mass profile based on archival Chandra X-ray observations and find it to be ~35% lower than our lensing-derived profile at r_2500_~600kpc. Agreement can be achieved by a halo elongated with a ~2:1 axis ratio along our LOS. For this elongated halo model, we find M_vir_=(1.7+/-0.2)x10^15^M_{sun}_h^-1^_70_ and c_vir_=4.6+/-0.2, placing rough lower limits on these values. The need for halo elongation can be partially obviated by non-thermal pressure support and, perhaps entirely, by systematic errors in the X-ray mass measurements. We estimate the effect of background structures based on MMT/Hectospec spectroscopic redshifts and find that these tend to lower M_vir_ further by ~7% and increase c_vir_by ~5%.
- ID:
- ivo://CDS.VizieR/J/A+A/654/A135
- Title:
- 12 strong galactic bars CO spectra
- Short Name:
- J/A+A/654/A135
- Date:
- 22 Feb 2022
- Publisher:
- CDS
- Description:
- While some galactic bars show recent massive star formation (SF) along them, some others present a lack of it. Whether bars with low level of SF are a consequence of low star formation efficiency, low gas inflow rate, or dynamical effects, remains a matter of debate. In order to study the physical conditions that enable or prevent SF, we perform a multi-wavelength analysis of 12 strongly barred galaxies with total stellar masses log10(M*/M_{sun}_){in}[10.2,11], chosen to host different degrees of SF along the bar major axis without any prior condition on gas content. We observe the CO(1-0) and CO(2-1) emission within bars with the IRAM-30m telescope (beam sizes of 1.7-3.9kpc and 0.9-2.0kpc, respectively; 7-8 pointings per galaxy on average). We estimate molecular gas masses (Mmol) from the CO(1-0) and CO(2-1) emissions. SF rates (SFR) are calculated from GALEX near-ultraviolet (UV) and WISE 12um images within the beam-pointings, covering the full bar extent (SFRs are also derived from far-UV and 22um). Results. We detect molecular gas along the bars of all probed galaxies. Molecular gas and SFR surface densities span the ranges log10({Sigma}_mol_/[M_{sun}_/pc^2^]){in}[0.4,2.4] and log10({Sigma}_SFR_/[M_{sun}_/pc/kpc^2^]){in}[-3.25,-0.75], respectively. The star formation efficiency (SFE=SFR/Mmol) in bars varies between galaxies by up to an order of magnitude (SFE{in}[0.1,1.8]Gyr^-1^). On average, SFEs are roughly constant along bars. SFEs are not significantly different from the mean value in spiral galaxies reported in the literature (~0.43Gyr^-1^), regardless of whether we estimate Mmol from CO(1-0) or CO(2-1). Interestingly, the higher the total stellar mass of the host galaxy, the lower the SFE within their bars. In particular, the two galaxies in our sample with lowest SFE and {Sigma}_SFR_ (NGC 4548 and NGC 5850, SFE<=0.25Gyr^-1^, {Sigma}_SFR_<=10^-2.25^M_{sun}_/yr/kpc^2^, M*<=10^10.7^M_{sun}_) are also the ones hosting massive bulges and signs of past interactions with nearby companions. We present a statistical analysis of the SFE in bars for a sample of 12 galaxies. The SFE in strong bars is not systematically inhibited (either in the central, mid- or end-parts of the bar). Both environmental and internal quenching are likely responsible for the lowest SFEs reported in this work.
- ID:
- ivo://CDS.VizieR/J/other/RAA/20.2
- Title:
- Strong galaxy-galaxy lensing in SDSS-III BOSS
- Short Name:
- J/other/RAA/20.2
- Date:
- 03 Dec 2021 00:49:25
- Publisher:
- CDS
- Description:
- Strong lensing is one of the most spectacular views in the universe. Many cosmological applications have been proposed, but the number of such lensing systems is still limited. In this work, we applied an improved version of a previously developed spectroscopic lensing search method to the SDSS-III BOSS and proposed a list of highly possible candidates. Follow-up CFHT Megacam imaging observations were performed for five systems, and two out of five are probably strong lensing systems with at least one image close to the central galaxy, although no counter images are detected.