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731. A Hubble diagram for quasars
ID:
ivo://CDS.VizieR/J/ApJ/815/33
Title:
A Hubble diagram for quasars
Short Name:
J/ApJ/815/33
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a new method to test the {Lambda}CDM cosmological model and to estimate cosmological parameters based on the nonlinear relation between the ultraviolet and X-ray luminosities of quasars. We built a data set of 1138 quasars by merging several samples from the literature with X-ray measurements at 2keV and SDSS photometry, which was used to estimate the extinction-corrected 2500{AA} flux. We obtained three main results: (1) we checked the nonlinear relation between X-ray and UV luminosities in small redshift bins up to z~6, confirming that the relation holds at all redshifts with the same slope; (2) we built a Hubble diagram for quasars up to z~6, which is well matched to that of supernovae in the common z=0-1.4 redshift interval and extends the test of the cosmological model up to z~6; and (3) we showed that this nonlinear relation is a powerful tool for estimating cosmological parameters. Using the present data and assuming a {Lambda}CDM model, we obtain {Omega}_M_=0.22_-0.08_^+0.10^ and {Omega}_{Lambda}_=0.92-0.30_^+0.18^ ({Omega}=0.28+/-0.04 and {Omega}_{Lambda}_=0.73+/-0.08 from a joint quasar-SNe fit). Much more precise measurements will be achieved with future surveys. A few thousand SDSS quasars already have serendipitous X-ray observations from Chandra or XMM-Newton, and at least 100000 quasars with UV and X-ray data will be made available by the extended ROentgen Survey with an Imaging Telescope Array all-sky survey in a few years. The Euclid, Large Synoptic Survey Telescope, and Advanced Telescope for High ENergy Astrophysics surveys will further increase the sample size to at least several hundred thousand. Our simulations show that these samples will provide tight constraints on the cosmological parameters and will allow us to test for possible deviations from the standard model with higher precision than is possible today.
732. AIASCR VO Services Registry
ID:
ivo://asu.cas.cz/__system__/services/registry
Title:
AIASCR VO Services Registry
Short Name:
AIASCR Reg
Date:
16 Sep 2024 11:02:34
Publisher:
The staff at the AIASCR VO Services
Description:
The publishing registry for the AIASCR VO Services.
733. AI CMi UBV light curves
ID:
ivo://CDS.VizieR/J/PAZh/43/460
Title:
AI CMi UBV light curves
Short Name:
J/PAZh/43/460
Date:
21 Oct 2021
Publisher:
CDS
Description:
The U BV photometry and low-resolution spectroscopy for the semiregular variable AI CMi, a candidate for post-AGB objects, performed in 1996-2016 and 2000-2013, respectively, are presented. The star showed multiperiodic brightness variations with an amplitude up to 1.5m in the V band, a significant (up to 0.4m) bluing of the B-V and U-B colors as the star faded, and a change of its spectrum from G5 I to K3-5 I, depending on its brightness. A possible long-term fading of AI CMi below 8.5m in the period from May 2013 to early 2015 is observed in the light curve. The colors in this episode did not change the pattern of their unusual behavior with brightness. The main feature of the spectrum for AI CMi is the appearance and strengthening of TiO absorption bands as its brightness declines, which are atypical in the spectra of ordinary G5-K3 supergiants. The bluing of the B-V and U-B colors is interpreted as the blanketing of stellar radiation predominantly in V (and to a lesser extent in B) by the TiO absorption bands whose intensity increases dramatically with decreasing brightness. Another cause of the bluing can be the scattering of stellar radiation by small dust particles in the gas-dust shell of AI CMi. The star's continuum-normalized spectra over the period from 2000 to 2013 in the wavelength range 4200 to 7700 or 9200{AA} are presented. These were taken at different phases of the pulsation cycle and clearly demonstrate the behavior of the TiO absorption bands depending on the V magnitude and B-V color. The equivalent widths of individual TiO bands were measured, and their correlation with the photometric parameters of the star is shown. AI CMi belongs to the O-rich branch of AGB/post-AGB supergiants and has a luminosity of ~4000L_{sun}_ at a distance of 1500+/-700pc. The mass of AI CMi is most likely small and close to the lower mass limit for post-AGB stars. The connection of the star's pulsational activity and nonstationary wind with the formation of its molecular and dust shells is discussed briefly.
734. AIMSS Project. I. Compact Stellar Systems
ID:
ivo://CDS.VizieR/J/MNRAS/443/1151
Title:
AIMSS Project. I. Compact Stellar Systems
Short Name:
J/MNRAS/443/1151
Date:
21 Oct 2021
Publisher:
CDS
Description:
We describe the structural and kinematic properties of the first compact stellar systems discovered by the Archive of Intermediate Mass Stellar Systems project. These spectroscopically confirmed objects have sizes (~6<R_e_[pc]<500) and masses (~2x10^6^<M*/M_{sun}_<6x10^9^) spanning the range of massive globular clusters, ultracompact dwarfs (UCDs) and compact elliptical galaxies (cEs), completely filling the gap between star clusters and galaxies. Several objects are close analogues to the prototypical cE, M32. These objects, which are more massive than previously discovered UCDs of the same size, further call into question the existence of a tight mass-size trend for compact stellar systems, while simultaneously strengthening the case for a universal 'zone of avoidance' for dynamically hot stellar systems in the mass-size plane. Overall, we argue that there are two classes of compact stellar systems (1) massive star clusters and (2) a population closely related to galaxies. Our data provide indications for a further division of the galaxy-type UCD/cE population into two groups, one population that we associate with objects formed by the stripping of nucleated dwarf galaxies, and a second population that formed through the stripping of bulged galaxies or are lower mass analogues of classical ellipticals. We find compact stellar systems around galaxies in low- to high-density environments, demonstrating that the physical processes responsible for forming them do not only operate in the densest clusters.
735. A1763 infrared and optical photometry
ID:
ivo://CDS.VizieR/J/AJ/139/434
Title:
A1763 infrared and optical photometry
Short Name:
J/AJ/139/434
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a photometric analysis of the galaxy cluster Abell 1763 at visible and infrared wavelengths. Included are fully reduced images in r', J, H, and Ks obtained using the Palomar 200in telescope, as well as the IRAC and MIPS images from Spitzer. The cluster is covered out to approximately 3 virial radii with deep 24um imaging (a 5{sigma} depth of 0.2mJy). This same field of ~40'x40' is covered in all four IRAC bands as well as the longer wavelength MIPS bands (70 and 160um). The r' imaging covers ~0.8deg^2^ down to 25.5mag, and overlaps with most of the MIPS field of view. The J, H, and Ks images cover the cluster core and roughly half of the filament galaxies, which extend toward the neighboring cluster, Abell 1770. This first, in a series of papers on Abell 1763, discusses the data reduction methods and source extraction techniques used for each data set. We present catalogs of infrared sources (with 24 and/or 70um emission) and their corresponding emission in the optical (u', g', r', i', z'), and near- to far-IR (J, H, Ks, IRAC, and MIPS 160um). We provide the catalogs and reduced images to the community through the NASA/IPAC Infrared Science Archive.
736. A2125 in X-ray
ID:
ivo://CDS.VizieR/J/ApJ/611/821
Title:
A2125 in X-ray
Short Name:
J/ApJ/611/821
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an 82ks Chandra ACIS-I observation of a large-scale hierarchical complex, which consists of various clusters/groups of galaxies and low surface brightness X-ray emission at z=0.247. This high-resolution Chandra observation allows us for the first time to separate unambiguously the X-ray contributions from discrete sources and large-scale diffuse hot gas. We detect 99 X-ray sources in a 17{arcmin}x17{arcmin} field.
737. AIP DaCHS Registry
ID:
ivo://aip.gavo.org/__system__/services/registry
Title:
AIP DaCHS Registry
Short Name:
AIP GAVO RG
Date:
17 Jul 2024 11:34:41
Publisher:
The staff at the AIP DaCHS
Description:
The publishing registry for the AIP DaCHS.
738. AIP DaCHS TAP service
ID:
ivo://aip.gavo.org/tap
Title:
AIP DaCHS TAP service
Short Name:
AIP GAVO TAP
Date:
17 Jul 2024 11:34:42
Publisher:
GAVO at Leibniz-Institute for Astrophysics Potsdam
Description:
The AIP DaCHS's TAP end point. The Table Access Protocol (TAP) lets you execute queries against our database tables, inspect various metadata, and upload your own data. It is thus the VO's premier way to access public data holdings. Tables exposed through this endpoint include: dens256, fof, redshifts from the bolshoi schema, columns, services, tables from the glots schema, fof, fofmtree, fofparticles, particles85, redshifts, treesnapnums from the mdr1 schema, rave_dr4 from the ravedr4 schema, alt_identifier, authorities, capability, g_num_stat, interface, intf_param, registries, relationship, res_date, res_detail, res_role, res_schema, res_subject, res_table, resource, stc_spatial, stc_spectral, stc_temporal, subject_uat, table_column, tap_table, validation from the rr schema, columns, groups, key_columns, keys, schemas, tables from the tap_schema schema.
739. AIP GAVO
ID:
ivo://aip.gavo.org
Title:
AIP GAVO
Short Name:
AIP GAVO
Date:
16 Jul 2024 13:59:36
Publisher:
GAVO at Leibniz-Institute for Astrophysics Potsdam
Description:
GAVO at AIP is a single-client authority forregistering data sets in the AIP DaCHS-run data center.
740. A Jupiter-mass companion around HD 109246
ID:
ivo://CDS.VizieR/J/A+A/523/A88
Title:
A Jupiter-mass companion around HD 109246
Short Name:
J/A+A/523/A88
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report the detection of a Jupiter-mass planet discovered with the SOPHIE spectrograph mounted on the 1.93-m telescope at the Haute-Provence Observatory. The new planet orbits HD 109246, a G0V star slightly more metallic than the Sun. HD 109246b has a minimum mass of 0.77M_{jup}_, an orbital period of 68 days, and an eccentricity of 0.12. It is placed in a sparsely populated region of the period distribution of extrasolar planets. We also present a correction method for the so-called seeing effect that affects the SOPHIE radial velocities. We complement this discovery announcement with a description of some calibrations that are implemented in the SOPHIE automatic reduction pipeline. These calibrations allow the derivation of the photon-noise radial velocity uncertainty and some useful stellar properties (vsini, [Fe/H], log R'hk) directly from the SOPHIE data.

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