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2421. Spectral analysis of 2010-11 outburst of GX 339-4
ID:
ivo://CDS.VizieR/J/A+A/542/A56
Title:
Spectral analysis of 2010-11 outburst of GX 339-4
Short Name:
J/A+A/542/A56
Date:
21 Oct 2021
Publisher:
CDS
Description:
The Galactic transient black hole candidate (BHC) GX 339-4 exhibited several outbursts at regular intervals of about two to three years in the Rossi X-ray Timing Explorer (RXTE) era. After remaining in an almost quiescent state for three long years, it again became X-ray active in January, 2010, continuing to be so over the next ~14 months. We study the timing and spectral properties of the BHC during its recent outburst and understand the behavioral change in the accretion flow dynamics associated with the evolution of the various X-ray features. The detailed analysis of the temporal and spectral properties of the source during this outburst are carried out using archival data of the RXTE PCA instrument. We analyze a total of 236 observational intervals consisting of 419 days of data observed by RXTE, from 2010 January 12 to 2011 March 6.
2422. Spectral analysis of V510 Pup
ID:
ivo://CDS.VizieR/J/AZh/81/333
Title:
Spectral analysis of V510 Pup
Short Name:
J/AZh/81/333
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have carried out a detailed identification of lines in the optical spectrum of the post-AGB star V510Pup associated with the infrared source IRAS08005-2356. Absorbtion lines of the ions FeII, TiII, CrII, YII are presented at wavelengths from 4549 to 8546 A. The absorptions YII and other s-process elements are anomalously strong. There is also strong in the circumstellar C_2_ Swan bands. The profiles of most of the lines (of hydrogen and metals) display absorption-emission P Cyg type profiles. All the absorption lines are shifted toward shorter wavelengths, suggesting an outflow of stellar material. The expansion velocity of the envelope derived from the Swan bands arising there is Vexp=42km/s. The highest wind velocity determined from the absorptional wings of FeII(42) P Cygni profiles reachs 240km/s. Based on the star's kinematic characteristics and the amount of interstellar absorption, the distance to this object is d~3-4kpc.
2423. Spectral and UBV analysis of {epsilon} Aur
ID:
ivo://CDS.VizieR/J/A+A/530/A146
Title:
Spectral and UBV analysis of {epsilon} Aur
Short Name:
J/A+A/530/A146
Date:
21 Oct 2021
Publisher:
CDS
Description:
A series of 353 red electronic spectra (from three observatories, mostly from 6300 to 6700{AA}) obtained between 1994 and 2010, and of 171 UBV photometric observations (from two observatories) of the 2010 eclipse, were analyzed in an effort to better understand epsilon Aur, the well-known, but still enigmatic eclipsing binary with the longest known orbital period (~27yrs).
2424. Spectral Atlas of Carbon Stars
ID:
ivo://CDS.VizieR/J/ApJS/105/419
Title:
Spectral Atlas of Carbon Stars
Short Name:
J/ApJS/105/419
Date:
21 Oct 2021
Publisher:
CDS
Description:
The authors compiled this moderate-resolution spectral atlas to aid in the classification of carbon stars on the Revised MK System (Keenan 1993PASP..105..905K) as refined and extended by the present work. Hence the main purpose of this atlas is to permit rapid and reasonably accurate comparison of the properties of carbon stars in the Solar neighborhood with those in the Galactic bulge, the Magellanic Clouds, and in other nearby external systems. The classification scheme employed makes no assumptions about evolutionary status of the stars but is based entirely on observable criteria. Spectra of 39 stars are presented in detail, along with a catalog of 119 carbon stars classified according to the Revised MK System; the catalog lists also the variability type from Kholopov (1985), and the instrument used. The table is a modified version of table 4 in the source reference. This classification catalog uses not only the stars we observed (the spectral data in this catalog) but also used other material -- photographic plates and some of the stars in the high resolution barnbaum atlas. Stars observed solely with those two instruments are so noted. The spectral files are the data for the standard Carbon Stars in Figs 1 and 2 of the paper.
2425. Spectral atlas of HD 50138
ID:
ivo://CDS.VizieR/J/A+A/508/309
Title:
Spectral atlas of HD 50138
Short Name:
J/A+A/508/309
Date:
21 Oct 2021
Publisher:
CDS
Description:
The observed spectral variation of HD50138 led different authors in the literature to classify it in a very large range of spectral types and luminosity classes (from B5 to A0 and III to Ia) and at different evolutionary stages, as either an HAeBe star or a classical Be. Based on new high-resolution optical spectroscopic data from 1999 and 2007, we perform a detailed spectral description, presenting the variations seen and discussing their possible origin. We tentatively suggest that a new shell phase could have taken place prior to our observations in 2007. We derive the interstellar extinction to HD50138 by taking into account the influences of the circumstellar matter in the form of dust and an ionized disk. We find a color excess value of E(B-V)=0.08mag. Based on photometric data from the literature and the new Hipparcos distance, we obtain a revised set of parameters for HD50138, suggesting that it is a B6-7 III-V star. A discussion about the different evolutionary scenarios is also provided.
2426. Spectral atlas of massive stars around He I
ID:
ivo://CDS.VizieR/J/A+A/465/993
Title:
Spectral atlas of massive stars around He I
Short Name:
J/A+A/465/993
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a digital atlas of peculiar, high-luminosity massive stars in the near-infrared region (10470-11000{AA}) at medium resolution (R~7000). The spectra are centered around HeI 10830{AA}, which is formed in the wind of those stars, and is a crucial line to obtain their physical parameters. The instrumental configuration also sampled a rich variety of emission lines of FeII, MgII, CI, NI, and Pa{gamma}. Secure identifications for most spectral lines are given, based on synthetic atmosphere models calculated by our group. We also propose that two unidentified absorption features have interstellar and/or circumstellar origin. For the strongest one (10780{AA}) an empirical calibration between E(B-V) and equivalent width is provided. The atlas displays the spectra of massive stars organized in four categories, namely Be stars, OBA Iape (or luminous blue variables, LBV candidates and ex/dormant LBVs), OB supergiants and Wolf-Rayet stars. For comparison, the photospheric spectra of non emission-line stars are presented. Selected LBVs were observed in different epochs from 2001 to 2004, and their spectral variability reveals that some stars, such as eta Car, AG Car and HR Car, suffered dramatic spectroscopic changes during this time interval.
2427. Spectral atlas of omega Cen post-MS stars
ID:
ivo://CDS.VizieR/J/MNRAS/382/1353
Title:
Spectral atlas of omega Cen post-MS stars
Short Name:
J/MNRAS/382/1353
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a spectral atlas of the post-main-sequence population of the most massive Galactic globular cluster, omega Centauri. Spectra were obtained of more than 1500 stars selected as uniformly as possible from across the (B, B-V) colour-magnitude diagram of the proper motion cluster member candidates of van Leeuwen et al. (2000, Cat. <J/A+A/360/472>). The spectra were obtained with the 2dF multifibre spectrograph at the Anglo-Australian Telescope, and cover the approximate range {lambda}~3840-3940{AA} at a resolving power of {lambda}/{Delta}{lambda}~=2000. This constitutes the most comprehensible spectroscopic survey of a globular cluster. We measure the radial velocities, effective temperatures, metallicities and surface gravities by fitting ATLAS9 stellar atmosphere models. We analyse the cluster membership and stellar kinematics, interstellar absorption in the Ca II K line at 3933{AA}, the RR Lyrae instability strip and the extreme horizontal branch, the metallicity spread and bimodal CN abundance distribution of red giants, nitrogen and s-process enrichment, carbon stars, pulsation-induced Balmer line emission on the asymptotic giant branch (AGB), and the nature of the post-AGB and UV-bright stars. Membership is confirmed for the vast majority of stars, and the radial velocities clearly show the rotation of the cluster core. We identify long-period RR Lyrae-type variables with low gravity, and low-amplitude variables coinciding with warm RR Lyrae stars. A barium enhancement in the coolest red giants indicates that third dredge-up operates in AGB stars in omega Cen. This is distinguished from the pre-enrichment by more massive AGB stars, which is also seen in our data. The properties of the AGB, post-AGB and UV-bright stars suggest that red giant branch (RGB) mass loss may be less efficient at very low metallicity, [Fe/H]<<1, increasing the importance of mass loss on the AGB. The catalogue and spectra are made available via Centre Donnees de Strasbourg (CDS).
2428. Spectral Atlas of P Cygni in range 4840-6760A
ID:
ivo://CDS.VizieR/J/A+AS/114/499
Title:
Spectral Atlas of P Cygni in range 4840-6760A
Short Name:
J/A+AS/114/499
Date:
21 Oct 2021
Publisher:
CDS
Description:
Using the coude spectrograph of the NAO 2m RCC telescope at the Rhodope Mountains, Bulgaria, 11 spectra in the wavelength range from 4840 to 6760A of P Cygni were obtained during the years 1981, 1983 and 1985. By averaging these spectra we achieved a S/N-ratio of about 50. Here we present a spectral atlas with complete line identifications. Apart from the lines listed by de Groot (1969) many pure bright lines are identified. Most of them are lines of FeIII with high multiplet numbers and NII. Further emission lines are those of SiII multiplets 2, 4 and 5. A new feature is SII spectrum in absorption and emission. In addition to the forbidden lines discovered by Stahl et al. (1991, 1993) three new lines, [FeII19] {lambda}5159, [FeII18] {lambda}5273 and [FeII34] {lambda}5477 are identified. The presence of some [TiII9] lines as well as the red lines of [NII1] is considered as quite probable.
2429. Spectral atlas of peculiar stars
ID:
ivo://CDS.VizieR/J/AJ/140/1758
Title:
Spectral atlas of peculiar stars
Short Name:
J/AJ/140/1758
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present an Echelle+CCD, high S/N, high resolution (R=20000) spectroscopic atlas of 108 well-known objects representative of the most common types of peculiar and variable stars. The wavelength interval extends from 4600 to 9400{AA}, and includes the RAVE, Gaia and HERMES wavelength ranges. Multi-epoch spectra are provided for the majority of observed stars. A total of 425 spectra of peculiar stars are presented, which have been collected during 56 observing nights between November 1998 and August 2002. The spectra are given in FITS format and heliocentric wavelengths, with accurate subtraction of both the sky background and the scattered light. Auxiliary material useful for custom applications (telluric dividers, spectro-photometric stars, flat-field tracings) is also provided. The atlas aims to provide a homogeneous database of the spectral appearance of stellar peculiarities, a tool useful both for classification purposes and inter-comparison studies. It could also serve the planning for and training of automated classification algorithms designed for RAVE, Gaia, HERMES and other large scale spectral surveys. The spectrum of XX Oph is discussed in some detail as an example of the content of the present atlas.
2430. Spectral classification for 631 {rho}Puppis stars
ID:
ivo://CDS.VizieR/J/AJ/160/52
Title:
Spectral classification for 631 {rho}Puppis stars
Short Name:
J/AJ/160/52
Date:
09 Mar 2022
Publisher:
CDS
Description:
The {rho}Puppis stars are mid-F-type stars that show peculiar chemical-abundance patterns similar to those of the Am stars. Typically they exhibit overabundances of iron-peak elements such as Fe and Ni and s- and r-process elements such as Sr and Eu, and underabundances of certain other elements including He, Ca, and Sc. It has been proposed that these stars are evolving Am stars passing through the short-lived phase that occurs between the re-establishment of convection and the consequent erasure of their chemical peculiarities. In this paper we suggest a second hypothesis: these stars may have acquired their peculiar abundance patterns in a fashion similar to the Barium stars, i.e., they may have gained the s-process element enhancements via mass transfer from a once asymptotic giant-branch companion star, now turned white dwarf. This study will detail our efforts to investigate the {rho}Puppis stars with regard to these two hypotheses, with a view to understanding these stars and their significance in terms of stellar evolution. We have performed a spectral classification survey, and a detailed chemical-abundance analysis of selected {rho}Puppis stars. This paper gives an overview of the {rho}Puppis stars and describes the spectral classification survey which has increased the number of {rho}Puppis stars currently known from 6 to 49. A future paper will describe the chemical-abundance analysis which should provide insight into the nature of these stars.

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