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1231. Atmospheric parameters of stars for UV models
ID:
ivo://CDS.VizieR/J/A+A/538/A143
Title:
Atmospheric parameters of stars for UV models
Short Name:
J/A+A/538/A143
Date:
21 Oct 2021
Publisher:
CDS
Description:
The spectral predictions of stellar population models are not as accurate in the ultra-violet (UV) as in the optical wavelength domain. One of the reasons is the lack of high-quality stellar libraries. The New Generation Stellar Library (NGSL), recently released, represents a significant step towards the improvement of this situation. To prepare NGSL for population synthesis, we determined the atmospheric parameters of its stars, we assessed the precision of the wavelength calibration and characterised its intrinsic resolution. We also measured the Galactic extinction for each of the NGSL stars. For our analyses we used ULySS, a full spectrum fitting package, fitting the NGSL spectra against the MILES interpolator. We find that the wavelength calibration is precise up to 0.1pix, after correcting a systematic effect in the optical range. The spectral resolution varies from 3{AA} in the UV to 10{AA} in the near-infrared (NIR), corresponding to a roughly constant reciprocal resolution R~1000 and an instrumental velocity dispersion 130km/s. We derived the atmospheric parameters homogeneously. The precision for the FGK stars is 42K, 0.24 and 0.09dex for Teff, logg and [Fe/H], respectively. The corresponding mean errors are 29K, 0.50 and 0.48dex for the M stars, and for the OBA stars they are 4.5 percent, 0.44 and 0.18dex. The comparison with the literature shows that our results are not biased.
1232. Atmospheric param. of 169 FGKM stars
ID:
ivo://CDS.VizieR/J/MNRAS/434/1422
Title:
Atmospheric param. of 169 FGKM stars
Short Name:
J/MNRAS/434/1422
Date:
21 Oct 2021
Publisher:
CDS
Description:
The asteroseismic and planetary studies, like all research related to stars, need precise and accurate stellar atmospheric parameters as input. We aim at deriving the effective temperature (Teff), the surface gravity (logg), the metallicity ([Fe/H]), the projected rotational velocity (vsini) and the MK type for 169 F-, G-, K- and M-type Kepler targets which were observed spectroscopically from the ground with five different instruments. We use two different spectroscopic methods to analyse 189 high-resolution, high-signal-to-noise spectra acquired for the 169 stars. For 67 stars, the spectroscopic atmospheric parameters are derived for the first time. KIC 9693187 and 11179629 are discovered to be double-lined spectroscopic binary systems. The results obtained for those stars for which independent determinations of the atmospheric parameters are available in the literature are used for a comparative analysis. As a result, we show that for solar-type stars the accuracy of present determinations of atmospheric parameters is +/-150K in Teff, +/-0.15dex in [Fe/H] and +/-0.3dex in logg. Finally, we confirm that the curve-of-growth analysis and the method of spectral synthesis yield systematically different atmospheric parameters when they are applied to stars hotter than 6000K.
1233. ATNF Pulsar Catalog
ID:
ivo://nasa.heasarc/atnfpulsar
Title:
ATNF Pulsar Catalog
Short Name:
ATNF
Date:
21 Feb 2025
Publisher:
NASA/GSFC HEASARC
Description:
The Australia Telescope National Facility (ATNF) Pulsar Catalog is a catalog of known pulsars compiled by R.N. Manchester et al. and is descended from pulsar database used for the paper "Catalog of 558 Pulsars" by J.H. Taylor, R.N. Manchester and A.G. Lyne 1993, ApJS, 88, 529-568. The current catalog has been supplemented by inclusion of published data from more recent radio surveys, in particular, the Parkes Multibeam (PM) Pulsar Survey (Manchester et al. 2001, MNRAS, 328, 17-35) [available at the HEASARC as the PMPULSAR table] and the Swinburne Intermediate Latitude Pulsar Survey (Edwards et al. 2001, MNRAS, 326, 358-374), both made using the ATNF Parkes 64-m radio telescope. Binary parameters for known binary pulsars are also included as well as all available astrometric and spin parameter information for all pulsars. The catalog includes all published rotation-powered pulsars. Two separate small subsets of pulsars detected only at high energies are also included in the current table: the first group comprises X-ray and gamma-ray pulsars which are apparently powered by spin-down energy, but which have not been detected at radio wavelengths, while the second group contains anomalous X-ray pulsars (AXPs) and soft-gamma-ray repeaters (SGRs) for which coherent pulsations have been detected. Accretion-powered pulsars such as Her X-1 and the recently discovered X-ray millisecond pulsars such as SAX J1808.4-3658 are not included in this table, however. Many people have contributed to the compilation of the data contained in this catalog and the database that it was derived from. The authors particularly thank Andrew Lyne of the University of Manchester, Jodrell Bank Observatory, David Nice of Princeton University, and Russell Edwards, then at Swinburne University of Technology. The also acknowledge the efforts of Warwick University students Adam Goode and Steven Thomas who compiled and checked a recent version of the database. The original (summer 2003) database at the ATNF website was compiled with the invaluable assistance of Maryam Hobbs, while the ATNF web interface was designed and constructed by Albert Teoh, a Summer Vacation Scholar at the ATNF in 2002/2003. The authors would appreciate if anyone making use of this catalog in a publication acknowledges the source of their information by quoting the ATNF Pulsar Catalog website address of <a href="http://www.atnf.csiro.au/research/pulsar/psrcat/">http://www.atnf.csiro.au/research/pulsar/psrcat/</a> This database table was initially created by the HEASARC in January 2002. It was revised in March 2002, in June 2003, and again in January 2014. It is based on the table obtained from <a href="http://www.atnf.csiro.au/research/pulsar/psrcat/expert.html">http://www.atnf.csiro.au/research/pulsar/psrcat/expert.html</a>. <p> Changes to the catalog are logged at <a href="http://www.atnf.csiro.au/research/pulsar/psrcat/catalogueHistory.html">http://www.atnf.csiro.au/research/pulsar/psrcat/catalogueHistory.html</a>. <p> The HEASARC table will be updated on a weekly basis whenever the original ATNF database table is updated. This is a service provided by NASA HEASARC .
1234. ATNF Pulsar Catalogue
ID:
ivo://CDS.VizieR/B/psr
Title:
ATNF Pulsar Catalogue
Short Name:
B/psr
Date:
21 Oct 2021
Publisher:
CDS
Description:
The catalogue is a compilation of the principal observed parameters of pulsars, including positions, timing parameters, pulse widths, flux densities, proper motions, distances, and dispersion, rotation, and scattering measures. It also lists the orbital elements of binary pulsars, and some commonly used parameters derived from the basic measurements. The catalogue includes all published rotation-powered pulsars, including those detected only at high energies. It also includes Anomalous X-ray Pulsars (AXPs) and Soft Gamma-ray Repeaters (SGRs) for which coherent pulsations have been detected. However, it excludes accretion-powered pulsars such as Her X-1 and the recently discovered X-ray millisecond pulsars.
1235. Atomic carbon observations of H II regions
ID:
ivo://CDS.VizieR/J/ApJ/517/282
Title:
Atomic carbon observations of H II regions
Short Name:
J/ApJ/517/282
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report observations of atomic carbon (C I [^3^P - ^3^P_0_]) for a sample of 49 southern hemisphere H II regions using the Antarctic Submillimeter Telescope and Remote Observatory. The sources are compact and isolated members of the Wilson et al. (1970) H109{alpha} radio recombination line (RRL) catalog. The fourth Galactic quadrant is well covered by the sample. Atomic carbon emission is detected toward all of the regions, with multiple C I emission components found toward most sources. The RRL velocity is used to identify the C I emission associated with the H II region. We measure the mean velocity difference between the C I and RRL emission to be 0.8{+/-}2.8 km s^-1^. Within the measurement errors this is exact agreement in velocity; we conclude that all H II regions have associated C I emission. The mean C I line temperature of these components is 2.4{+/-}1.8 K, compared with 0.7{+/-}0.7 K for the C I emission components not associated with the H II region. This suggests that C I intensity is dominated by local heating. The FWHM line width of C I gas associated with H II regions also is marginally greater than that found for unassociated gas (6.7{+/-}3.0, compared with 4.8{+/-}2.4 km s-1).
1236. Atomic data for unblended lines in FGK stars
ID:
ivo://CDS.VizieR/J/A+A/624/A60
Title:
Atomic data for unblended lines in FGK stars
Short Name:
J/A+A/624/A60
Date:
21 Oct 2021
Publisher:
CDS
Description:
Fundamental atomic transition parameters, such as oscillator strengths and rest wavelengths, play a key role in modelling and understanding the chemical composition of stars in the universe. Despite the significant work under way to produce these parameters for many astrophysically important ions, uncertainties in these parameters remain large and can limit the accuracy of chemical abundance determinations. The Belgian repository of fundamental atomic data and stellar spectra (BRASS) aims to provide a large systematic and homogeneous quality assessment of the atomic data available for quantitative spectroscopy. BRASS shall compare synthetic spectra against extremely high-quality observed spectra, at a resolution of ~85000 and signal-noise ratios of ~1000, for approximately 20 bright BAFGK spectral-type stars, in order to critically evaluate the atomic data available for over a thousand potentially useful spectral lines. A large-scale homogeneous selection of atomic lines is performed by synthesising theoretical spectra of literature atomic lines for FGK-type stars including the Sun, resulting in a selection of 1091 theoretically deep and unblended lines in the wavelength range 4200-6800{AA}, which may be suitable for quality assessment. Astrophysical log(gf) values are determined for the 1091 transitions using two commonly employed methods. The agreement of these log(gf) values are used to select well-behaved lines for quality assessment. We found 845 atomic lines to be suitable for quality assessment, of which 408 were found to be robust against systematic differences between analysis methods. Around 53% of the quality-assessed lines were found to have at least one literature log(gf) value in agreement with our derived values, though the remaining values can disagree by as much as 0.5dex. Only ~38% of FeI lines were found to have sufficiently accurate log(gf) values, increasing to ~70-75% for the remaining Fe-group lines.
1237. Atomic lines in spectra of RR Lyrae & RHB stars
ID:
ivo://CDS.VizieR/J/AJ/157/153
Title:
Atomic lines in spectra of RR Lyrae & RHB stars
Short Name:
J/AJ/157/153
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have derived relations between FWHMs and equivalent widths of metallic absorption lines in the spectra of RR Lyrae stars to estimate new upper limits on the axial equatorial rotational velocities of RR Lyrae and metal-poor red horizontal branch (RHB) stars. We have also derived the variations of RR Lyrae macroturbulent velocities during the pulsation cycles. In RRab cycles, the line widths are dominated by phase-dependent convolutions of axial rotation and macroturbulence, which we designate as V_macrot_. The behavior of V_macrot_ is remarkably uniform among the RRab stars, but the behavior of V_macrot_ among RRc stars varies strongly from star to star. The RRab stars exhibit an upper limit on V_macrot_ of 5+/-1 km/s with weak evidence of an anticorrelation with T_eff_. The RRc minima range from 2 to 12 km/s. The abrupt decline in large rotations with decreasing T_eff_ at the blue boundary of the instability strip and the apparently smooth continuous variation among the RRab and RHB stars suggests that HB stars gain/lose surface angular momentum on timescales that are short compared to HB lifetimes. The V_macrot_ values for our metal-poor RHB stars agree well with those derived by Fourier analysis of an independent but less metal-poor sample of Carney et al. (2008AJ....135..892C); they conform qualitatively to the expectations of Tanner et al. (2013ApJ...778..117T). A general conclusion of our investigation is that surface angular momentum as measured by V_rot_sin(i) is not a reliable indicator of total stellar angular momentum anywhere along the HB.
1238. A unified supernova catalogue
ID:
ivo://CDS.VizieR/J/A+A/538/A120
Title:
A unified supernova catalogue
Short Name:
J/A+A/538/A120
Date:
28 Feb 2022 07:37:53
Publisher:
CDS
Description:
A supernova catalogue containing data for 5526 extragalactic supernovae that were discovered up to 2010 December 31. It combines several catalogues that are currently available online in a consistent and traceable way. During the comparison of the catalogues inconsistent entries were identified and resolved where possible. Remaining inconsistencies are marked transparently and can be easily identified. Thus it is possible to select a high-quality sample in a most simple way. Where available, redshift-based distance estimates to the supernovae were replaced by journal-refereed distances.
1239. A uniformly selected, all-sky, optical AGN catalog
ID:
ivo://CDS.VizieR/J/ApJ/872/134
Title:
A uniformly selected, all-sky, optical AGN catalog
Short Name:
J/ApJ/872/134
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have constructed an all-sky catalog of optical active galactic nuclei (AGNs) with z<0.09, based on optical spectroscopy, from the parent sample of galaxies in the 2MASS Redshift Survey, a near-complete census of the nearby universe. Our catalog consists of 1929 broad-line AGNs and 6562 narrow-line AGNs that satisfy the Kauffmann et al. (2003MNRAS.346.1055K) criteria, of which 3607 also satisfy the Kewley et al. (2006MNRAS.372..961K) criteria. We also report emission-line widths, fluxes, flux errors, and signal-to-noise ratios (S/Ns) of all the galaxies in our spectroscopic sample, allowing users to customize the selection criteria. Although we uniformly processed the spectra of galaxies from a homogeneous parent sample, inhomogeneities persist owing to the differences in the quality of the obtained spectra, taken with different instruments, and the unavailability of spectra for ~20% of the galaxies. We quantify how the differences in spectral quality affect not only the AGN detection rates but also ratios of broad-line to narrow-line AGNs. We find that the inhomogeneities primarily stem from the continuum S/N in the spectra near the emission lines of interest. We fit for the AGN fraction as a function of continuum S/N and assign AGN likelihoods to galaxies that were not identified as AGNs using the available spectra. This correction results in a catalog suitable for statistical studies. This work also paves the way for a truly homogeneous and complete nearby AGN catalog by identifying galaxies whose AGN status needs to be verified with higher-quality spectra, quantifying the spectral quality necessary to do so.
1240. A universal pattern in halo magnetic fields
ID:
ivo://CDS.VizieR/J/A+A/649/A94
Title:
A universal pattern in halo magnetic fields
Short Name:
J/A+A/649/A94
Date:
22 Feb 2022
Publisher:
CDS
Description:
Magnetic fields in galaxy halos are in general very difficult to observe. Most recently, the Continuum HAlos in Nearby Galaxies - an EVLA Survey (CHANG-ES) collaboration investigated the radio halos of 35 nearby edge-on spiral galaxies in detail and detected large-scale magnetic fields in 16 of them. We used the CHANG-ES radio polarization data to create rotation measure (RM) maps for all galaxies in the sample and stack them with the aim of amplifying any underlying universal toroidal magnetic field pattern in the halo above and below the disk of the galaxy. We discovered a large-scale magnetic field in the central region of the stacked galaxy profile, which is attributable to an axial electric current that universally outflows from the center, both above and below the plane of the disk. A similar symmetry-breaking has also been observed in astrophysical jets, but never before in galaxy halos. This is an indication that galaxy halo magnetic fields are probably not generated by pure magnetohydrodynamic (MHD) processes in the central regions of galaxies. One such promising physical mechanism is the Cosmic Battery operating in the innermost accretion disk around the central supermassive black hole. We anticipate that our discovery will stimulate a more general discussion on the origin of astrophysical magnetic fields.

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