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- ID:
- ivo://mssl.ucl.ac.uk/community_test
- Title:
- Date:
- 25 Feb 2008 14:00:38
- Publisher:
- Description:
- ID:
- ivo://CDS.VizieR/J/ApJ/497/188
- Title:
- A103, A118 and A114 morphological studies
- Short Name:
- J/ApJ/497/188
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present the results of a program to study the detailed morphologies of galaxies in intermediate-redshift clusters and hence understand the physical origin of the enhanced star formation seen in the environments at earlier epochs. Deep, high-resolution imagery has been obtained of three rich clusters, AC 103, AC 118 and AC 114 at z=0.31, through the R (F702W) filter of the Wide Field Planetary Camera (WFPC2) of the Hubble Space Telescope (HST).
- ID:
- ivo://CDS.VizieR/J/ApJ/890/71
- Title:
- 5100{AA} continuum & emission lines LCs of PG2130+099
- Short Name:
- J/ApJ/890/71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- As one of the most interesting Seyfert 1 galaxies, PG 2130+099 has been the target of several reverberation mapping (RM) campaigns over the years. However, its measured broad H{beta} line responses have been inconsistent, with time lags of ~200days, ~25days, and ~10days being reported for different epochs while its optical luminosity changed no more than 40%. To investigate this issue, we conducted a new RM-campaign with homogenous and high cadence (about ~3days) for two years during 2017-2019 to measure the kinematics and structure of the ionized gas. We successfully detected time lags of broad H{beta}, HeII, HeI, and FeII lines with respect to the varying 5100{AA} continuum, revealing a stratified structure that is likely virialized with Keplerian kinematics in the first year of observations, but an inflow kinematics of the broad-line region from the second year. With a central black hole mass of 0.97_-0.18_^+0.15^x10^7^M_{sun}_, PG2130+099 has an accretion rate of 10^2.1+/-0.5^L_Edd_c^-2^, where L_Edd_ is the Eddington luminosity and c is speed of light, implying that it is a super-Eddington accretor and likely possesses a slim, rather than thin, accretion disk. The fast changes of the ionization structures of the three broad lines remain puzzling.
- ID:
- ivo://CDS.VizieR/J/ApJ/814/52
- Title:
- 3600-24700{AA} deep X-shooter spectrum of HH 1
- Short Name:
- J/ApJ/814/52
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present deep spectroscopic (3600-24700{AA}) X-shooter observations of the bright Herbig-Haro object HH 1, one of the best laboratories to study the chemical and physical modifications caused by protostellar shocks on the natal cloud. We observe atomic fine structure lines, HI and HeI recombination lines and H_2_ ro-vibrational lines (more than 500 detections in total). Line emission was analyzed by means of Non-local Thermal Equilibiurm codes to derive the electron temperature and density, and for the first time we are able to accurately probe different physical regimes behind a dissociative shock. We find a temperature stratification in the range 4000K/80000K, and a significant correlation between temperature and ionization energy. Two density regimes are identified for the ionized gas, a more tenuous, spatially broad component (density ~10^3^/cm^3^), and a more compact component (density>=10^5^/cm^3^) likely associated with the hottest gas. A further neutral component is also evidenced, having a temperature <~10000K and a density >10^4^/cm^3^. The gas fractional ionization was estimated by solving the ionization equilibrium equations of atoms detected in different ionization stages. We find that neutral and fully ionized regions co-exist inside the shock. Also, indications in favor of at least partially dissociative shock as the main mechanism for molecular excitation are derived. Chemical abundances are estimated for the majority of the detected species. On average, abundances of non-refractory/refractory elements are lower than solar of about 0.15/0.5dex. This indicates the presence of dust inside the medium, with a depletion factor of iron of ~40%.
- ID:
- ivo://CDS.VizieR/J/A+AS/137/521
- Title:
- 8500-8750{AA} high resolution spectroscopy
- Short Name:
- J/A+AS/137/521
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present an Echelle+CCD high resolution spectroscopic atlas mapping the MKK classification system over the wavelength interval lambda 8500-8750 A, centered on the near-IR triplet of Ca II. Table 2 lists all the 131 program stars with basic informations (magnitudes, coordinates, spectral types, metallicities, rotational velocities, variabilities) and the journal of observations; Table 3 shows our mapping of the MKK scheme in terms of spectral and luminosity classes; Table 4 lists the major un-blended absorption lines which we identified in our spectra
- ID:
- ivo://CDS.VizieR/J/A+AS/141/141
- Title:
- 8500-8750{AA} high resolution spectroscopy. II.
- Short Name:
- J/A+AS/141/141
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a library of synthetic spectra characterized by -2.5<=[Z/Z_{sun}_]<=+0.5, 4.5<=logg<=1.0, and T_eff_<=7500K computed at the same {lambda}/{Delta}{lambda}=20000 resolving power of the observed spectra given in Paper I (Munari, 1999, Cat. <J/A+AS/137/521>) for 131 standard stars mapping the MKK spectral classification system. This range of parameters includes the majority of the galactic stars expected to dominate the GAIA target population, i.e. F-G-K-M type stars with metallicity ranging from that of the galactic globular clusters to Population I objects. Extension to T_eff_>7500K will be given later on in this series. The 254 synthetic spectra presented here are based on Kurucz's codes and line data and have been computed over a more extended wavelength interval (7650-8750{AA}) than that currently baselined for implementation on GAIA, i.e. the 8500-8750{AA}. This last range is dominated by the near-IR Ca II triplet and the head of the Paschen series. The more extended wavelength range allows us to investigate the behaviour of other strong near-IR spectral features (severely contaminated by telluric absorptions in ground-based observed spectra) as the K I doublet (7664, 7699{AA}), the Na I doublet (8183, 8194{AA}) and the lines of Fe I multiplet N.60 at 8327 and 8388{AA}. The synthetic spectra support our previous conclusions about the superior performance of the Paschen/Ca II 8500-8750{AA} region in meeting the GAIA requirements when compared to other near-IR intervals of similar {Delta}{lambda}=250{AA}.
- ID:
- ivo://CDS.VizieR/J/A+A/366/1003
- Title:
- 8500-8750{AA} high resolution spectroscopy. III.
- Short Name:
- J/A+A/366/1003
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- In this paper we complete the library of synthetic spectra for the range 7650-8750{AA}, which includes the 8500-8750{AA} interval currently base-lined for the spectroscopic observations by GAIA, candidate ESA Cornerstone 5 mission. As for Paper II (Munari & Castelli, Cat. <J/A+AS/141/141>), the spectra are based on Kurucz's codes and line data. The explored metallicity, gravity and temperature ranges are -2.5<=[Z/Z_{sun}_]<=+0.5, 4.5<=logg<=2.0 and 7750<=T_eff_<=50000K, respectively. The 698 new spectra are computed at the same {lambda}/{Delta}{lambda}=20000 resolving power of the observed spectra given in Paper I (Munari & Castelli, Cat. <J/A+AS/137/521>) (131 standard stars mapping the MKK spectral classification system) and the 254 synthetic spectra of Paper II (characterized by T_eff_<=7500K).
- ID:
- ivo://CDS.VizieR/J/A+A/406/995
- Title:
- 8500-8750{AA} high resolution spectroscopy. IV.
- Short Name:
- J/A+A/406/995
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- A library of high resolution spectra of MK standard and reference stars, observed in support to the GAIA mission, is presented. The aim of this paper is to integrate the MK mapping of Paper I (<J/A+AS/137/521>) of this series as well as to consider stars over a wider range of metallicities. Radial velocities are measured for all the target stars.
- ID:
- ivo://CDS.VizieR/J/A+A/657/A25
- Title:
- A521 and Cosmic Snake ALMA abd HST images
- Short Name:
- J/A+A/657/A25
- Date:
- 16 Mar 2022 13:03:06
- Publisher:
- CDS
- Description:
- We study the spatially resolved physical properties of the Cosmic Snake arc in MACS J1206.2-0847 and the arc in Abell 0521 (A521). These are two strongly lensed galaxies at redshifts z=1.036 and z=1.044. We used observations of the Hubble Space Telescope (HST) and the Atacama Large Millimeter/submillimeter Array (ALMA). The former gives access to the star formation rate (SFR) and stellar mass (M*), and the latter to the H_2_ molecular gas mass (Mmol). HST and ALMA observations have similar angular resolutions of 0.15"-0.2", which with the help of strong gravitational lensing enable us to reach spatial resolutions down to ~30pc and ~100pc in these two galaxies, respectively. These resolutions are close to the resolution of observations of nearby galaxies. We study the radial profiles of SFR, M*, and Mmol surface densities of these high-redshift galaxies and compare the corresponding exponential scale lengths with those of local galaxies. We find that the scale lengths in the Cosmic Snake are about 0.5kpc-1.5kpc, and they are 3 to 10 times larger in A521. This is a significant difference knowing that the two galaxies have comparable integrated properties. These high-redshift scale lengths are nevertheless comparable to those of local galaxies, which cover a wide distribution. The particularity of our high-redshift radial profiles is the normalisation of the Mmol surface density profiles (Sigma Mmol), which are offset by up to a factor of 20 with respect to the profiles of z=0 counterparts. The SFR surface density profiles are also offset by the same factor as {SIGMA}Mmol, as expected from the Kennicutt-Schmidt law.
- ID:
- ivo://CDS.VizieR/J/A+A/523/A71
- Title:
- A and F stars abundances in the Hyades
- Short Name:
- J/A+A/523/A71
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Abundances of 15 chemical elements have been derived for 28 F and 16 A stars members of the Hyades open cluster in order to set constraints on self-consistent evolutionary models that include radiative and turbulent diffusion A spectral synthesis, iterative procedure was applied to derive the abundances from selected high-quality lines in high-resolution, high-signal-to-noise spectra obtained with SOPHIE and AURELIE at the Observatoire de Haute Provence.
- ID:
- ivo://irsa.ipac/Spitzer/Images/MIPSGAL
- Title:
- A 24 and 70 Micron Survey of the Inner Galactic Disk with MIPS
- Short Name:
- MIPSGAL
- Date:
- 27 Oct 2022 19:00:00
- Publisher:
- NASA/IPAC Infrared Science Archive
- Description:
- MIPSGAL is a survey of the inner 248 square degrees of the Galactic plane at 24 and 70 microns using the MIPS instrument aboard the Spitzer Space Telescope. The survey covers Galactic latitudes of -1° < b < +1° for Galactic longitudes of l < 62° and l > 298°. Version 3.0 of the MIPSGAL data includes mosaics only at 24um, but covering the entire survey region. |b| < 1° is covered for -68° < l < 69°, and |b| < 3° is covered for -8° < l < 9°.
- ID:
- ivo://CDS.VizieR/J/A+A/628/A67
- Title:
- 15273{AA} near-infrared DIB
- Short Name:
- J/A+A/628/A67
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The latest SDSS/APOGEE data release DR14 has provided an increased number of stellar spectra in the H band and associated stellar models using an innovative algorithm known as The Cannon. We took advantage of these novelties to extract the 15273{AA} near-infrared DIB and to study its link with dust extinction and emission. We modified our automated fitting methods dedicated for hot stars and used in earlier studies with some adaptations motivated by the change from early- or intermediate-type stars to red giants. A new method has also been developed to quantify the upper limits on DIB strengths. Careful and thorough examinations of the DIB parameters, the continuum shape and the quality of the adjustment of the model to the data were done. We compared our DIB measurements with the stellar extinctions Av from the Starhorse database. We then compared the resulting DIB-extinction ratio with the dust optical depth derived from Planck data, globally and also separately for nearby off-Plane cloud complexes. Our analysis has led to the production of a catalog containing 124 064 new measurements of the 15273{AA} DIB, allowing us to revisit the correlation between DIB strength and dust reddening.
- ID:
- ivo://CDS.VizieR/J/MNRAS/460/2193
- Title:
- A3407 + A3408 radial velocities
- Short Name:
- J/MNRAS/460/2193
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We carried out a dynamical study of the galaxy cluster pair A3407 and A3408 based on a spectroscopic survey obtained with the 4 metre Blanco telescope at the Cerro Tololo Interamerican Observatory, plus 6dF data, and ROSAT All-Sky Survey. The sample consists of 122 member galaxies brighter than m_R_=20. Our main goal is to probe the galaxy dynamics in this field and verify if the sample constitutes a single galaxy system or corresponds to an ongoing merging process. Statistical tests were applied to clusters members showing that both the composite system A3407 + A3408 as well as each individual cluster have Gaussian velocity distribution. A velocity gradient of ~847+/-114km/s was identified around the principal axis of the projected distribution of galaxies, indicating that the global field may be rotating. Applying the kmm algorithm to the distribution of galaxies, we found that the solution with two clusters is better than the single unit solution at the 99 per cent cl. This is consistent with the X-ray distribution around this field, which shows no common X-ray halo involving A3407 and A3408. We also estimated virial masses and applied a two-body model to probe the dynamics of the pair. The more likely scenario is that in which the pair is gravitationally bound and probably experiences a collapse phase, with the cluster cores crossing in less than ~1h^-1^Gyr, a pre-merger scenario. The complex X-ray morphology, the gas temperature, and some signs of galaxy evolution in A3408 suggest a post-merger scenario, with cores having crossed each other ~1.65h^-1^Gyr ago, as an alternative solution.
- ID:
- ivo://CDS.VizieR/J/ApJS/216/22
- Title:
- 3060-3700{AA} spectra analysis of early-type stars
- Short Name:
- J/ApJS/216/22
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present a comprehensive and sensitive unbiased survey of interstellar features in the near-UV range (3050-3700{AA}). We combined a large number of VLT/UVES archival observations of a sample of highly reddened early-type stars -typical diffuse interstellar band targets- and unreddened standards. We stacked the individual observations to obtain a reddened "superspectrum" in the interstellar rest frame with a signal-to-noise ratio exceeding 1500. We compared this to the analogous geocentric and stellar rest frame superspectra as well as to an unreddened superspectrum to find interstellar absorption features. We find 30 known features (11 atomic and 19 molecular) and tentatively detect up to 7 new interstellar absorption lines of unknown origin. Our survey is sensitive to narrow and weak features; telluric residuals preclude us from detecting broader features. For each sightline, we measured fundamental parameters (radial velocities, line widths, and equivalent widths) of the detected interstellar features. We also revisit upper limits for the column densities of small, neutral polycyclic aromatic hydrocarbon molecules that have strong transitions in this wavelength range.
- ID:
- ivo://CDS.VizieR/J/ApJ/850/34
- Title:
- 3000-25000{AA} spectroscopy of nearby M dwarfs
- Short Name:
- J/ApJ/850/34
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Recent studies of the stellar population in the solar neighborhood (<20pc) suggest that there are undetected white dwarfs (WDs) in multiple systems with main-sequence companions. Detecting these hidden stars and obtaining a more complete census of nearby WDs is important for our understanding of stellar and galactic evolution, as well as the study of explosive phenomena. In an attempt to uncover these hidden WDs, we present intermediate resolution spectroscopy over the wavelength range of 3000-25000{AA} of 101 nearby M dwarfs (dMs), observed with the Very Large Telescope X-Shooter spectrograph. For each star we search for a hot component superimposed on the dM spectrum. X-Shooter has excellent blue sensitivity and thus can reveal a faint hot WD despite the brightness of its red companion. Visual examination shows no clear evidence of a WD in any of the spectra. We place upper limits on the effective temperatures of WDs that may still be hiding by fitting dM templates to the spectra and modeling the WD spectra. On average our survey is sensitive to WDs hotter than about 5300K. This suggests that the frequency of WD companions of Teff>~5300K with separation of the order of <~50 au among the local dM population is <3% at the 95% confidence level.
- ID:
- ivo://nasa.heasarc/aavsovsx
- Title:
- AAVSO International Variable Star Index
- Short Name:
- AAVSOVSX
- Date:
- 03 May 2024
- Publisher:
- NASA/GSFC HEASARC
- Description:
- This database table contains Galactic stars known or suspected to be variable. It lists all stars that have an entry in the American Association of Variable Star Observers' (AAVSO) International Variable Star Index (VSX; <a href="http://www.aavso.org/vsx">http://www.aavso.org/vsx</a>). It consisted initially of the General Catalogue of Variable Stars (GCVS) and the New Catalogue of Suspected Variables (NSV) and was then supplemented with a large number of variable star catalogues, as well as individual variable star discoveries or variables found in the literature. Effort has also been invested to update the entries with the latest information regarding position, type and period and to remove duplicates. The VSX database is being continually updated and maintained. For historical reasons some objects outside of the Galaxy have been included. This table was created by the HEASARC based on the <a href="https://cdsarc.cds.unistra.fr/ftp/cats/B/vsx">CDS catalog B/vsx</a>. The CDS updates it regularly, and this HEASARC version is accordingly updated within a week of such updates. This is a service provided by NASA HEASARC .
- ID:
- ivo://CDS.VizieR/B/vsx
- Title:
- AAVSO International Variable Star Index VSX
- Short Name:
- B/vsx
- Date:
- 07 Mar 2022 08:38:01
- Publisher:
- CDS
- Description:
- This file contains Galactic stars known or suspected to be variable. It lists all stars that have an entry in the AAVSO International Variable Star Index (VSX; http://www.aavso.org/vsx). The database consisted initially of the General Catalogue of Variable Stars (GCVS) and the New Catalogue of Suspected Variables (NSV) and was then supplemented with a large number of variable star catalogues, as well as individual variable star discoveries or variables found in the literature. Effort has also been invested to update the entries with the latest information regarding position, type and period and to remove duplicates. The VSX database is being continually updated and maintained. For historical reasons some objects outside of the Galaxy have been included.
- ID:
- ivo://org.gavo.dc/apass/q/cone
- Title:
- AAVSO Photometric All Sky Survey (APASS) DR10
- Short Name:
- APASS DR10 cone
- Date:
- 23 Mar 2022 13:13:11
- Publisher:
- The GAVO DC team
- Description:
- AAVSO Photometric All-Sky Survey (APASS), underway since 2010, covers the entire sky from 7.5 < V < 16.5 magnitude, and in the BVugrizY bandpasses. A northern and a southern site are used, each with twin ASA 20cm astrographs and Apogee Aspen CG16m cameras, covering 2.9x2.9 square degrees with 2.6arcsec pixels. Landolt and SDSS standards are used for all-sky solutions, with typical 0.02mag calibration errors on the bright end. Data Release 10 is a complete reprocessing of all 500K images taken with the system, including hundreds of nights not part of DR9. Sextractor is used for star finding and centroiding; DAOPHOT is used for aperture photometry; the astrometry.net plate-solving library is used for basic astrometry, supplanted with more precise WCS that utilizes knowledge of the optical train distortions. With these changes, DR10 includes many more stars than prior releases. More information is available at http://www.aavso.org/apass.
- ID:
- ivo://CDS.VizieR/II/336
- Title:
- AAVSO Photometric All Sky Survey (APASS) DR9
- Short Name:
- II/336
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- The AAVSO Photometric All Sky Survey (APASS) project is designed to bridge the gap between the shallow Tycho2 two-bandpass photometric catalog that is complete to V=11 and the deeper, but less spatially-complete catalogs like SDSS or PanSTARRS. It can be used for calibration of a specific field; for obtaining spectral information about single sources, determining reddening in a small area of the sky; or even obtaining current-epoch astrometry for rapidly moving objects. The survey is being performed at two locations: near Weed, New Mexico in the Northern Hemisphere; and at CTIO in the Southern Hemisphere. Each site consists of dual bore-sighted 20cm telescopes on a single mount, designed to obtain two bandpasses of information simultaneously. Each telescope covers 9 square degrees of sky with 2.5arcsec pixels, with the main survey taken with B,V,g',r',i' filters and covering the magnitude range 10<V<17. A bright extension is underway, saturating at V=7 and extending the wavelength coverage from u' to Y. The current catalog is Data Release 9 and contains approximately 62 million stars. The American Association of Variable Star Observers is responsible for the overall management of the survey; a team of professional astronomers participate in the data analysis. The project was initially funded by the Robert Martin Ayers Sciences Fund, with a follow-on grant from the National Science Foundation.