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23731. Velocity and distance of methanol maser sources
ID:
ivo://CDS.VizieR/J/other/ChJAA/3.49
Title:
Velocity and distance of methanol maser sources
Short Name:
J/other/ChJAA/3.
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present a statistical analysis of 482 6.7GHz methanol maser sources from the available literature, on their maser emission and the characteristics of their associated infrared sources. On the color-color diagram, more than 70% of the objects fall within a very small region (0.57<=[25-12]<=1.30 and 1.30<=[60-12]<=2.50). This suggests that 6.7GHz methanol maser emission occurs only within a very short evolutionary phase during the earliest stage of star formation. The velocity ranges of the masers belong to two main groups: one from 1 to 10km/s, and one from about 11 to 20km/s. These velocity ranges indicate that the masers are probably associated with both disks and outflows. The correlations between the maser and infrared flux densities, and between the maser and infrared luminosities, suggest that far-infrared radiation is a possible pumping mechanism for the masers which most probably originate from some outer molecular envelopes or disks.
23732. Velocity and H{alpha} width of 22 Vul
ID:
ivo://CDS.VizieR/J/AJ/133/2669
Title:
Velocity and H{alpha} width of 22 Vul
Short Name:
J/AJ/133/2669
Date:
21 Oct 2021
Publisher:
CDS
Description:
The 22 Vul system is important for studying the winds and chromospheres of cool evolved stars because the G4 I component is rotating rapidly and probably faster than synchronously. We discuss the system's physical properties in the context of a wide range of constraints on them and propose values that may be marginally better than previous ones. We use H{alpha} spectroscopy to assess the variability of the cool star's wind, and archival IUE observations to measure variation of density in the wind and rotation of the chromosphere.
23733. Velocity and light curve analysis of three PPNe
ID:
ivo://CDS.VizieR/J/AJ/156/300
Title:
Velocity and light curve analysis of three PPNe
Short Name:
J/AJ/156/300
Date:
21 Oct 2021
Publisher:
CDS
Description:
We have obtained contemporaneous light, color, and radial velocity data for three proto-planetary nebulae (PPNe) over the years 2007 to 2015. The light and velocity curves of each show similar periods of pulsation, with photometric periods of 42 and 50 days for IRAS 17436+5003, 102 days for IRAS 18095+2704, and 35 days for IRAS 19475+3119. The light and velocity curves are complex with multiple periods and small, variable amplitudes. Nevertheless, at least over limited time intervals, we were able to identify dominant periods in the light, color, and velocity curves and compare the phasing of each. The color curves appear to peak with or slightly after the light curves while the radial velocity curves peak about a quarter of a cycle before the light curves. Similar results were found previously for two other PPNe, although for them the light and color appeared to be in phase. Thus, it appears that PPNe are brightest when smallest and hottest. These phase results differ from those found for classical Cepheid variables, where the light and velocity differ by half a cycle, and are hottest at about average size and expanding. However, they do appear to have similar phasing to the larger-amplitude pulsations seen in RV Tauri variables. Presently, few pulsation models exist for PPNe, and these do not fit the observations well, especially the longer periods observed. Model fits to these new light and velocity curves would allow masses to be determined for these post-AGB objects, and thereby provide important constraints to post-AGB stellar evolution models of low- and intermediate-mass stars.
23734. Velocity and light curves of RW Lac
ID:
ivo://CDS.VizieR/J/AJ/130/2838
Title:
Velocity and light curves of RW Lac
Short Name:
J/AJ/130/2838
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present 3004 differential observations in the V bandpass measured by a robotic telescope, as well as 36 pairs of radial velocities from high-resolution spectroscopic observations, of the detached, eccentric, EA-type, 10.37day period, double-lined eclipsing binary star RW Lac.
23735. Velocity and proper motion of OB associations
ID:
ivo://CDS.VizieR/J/MNRAS/400/518
Title:
Velocity and proper motion of OB associations
Short Name:
J/MNRAS/400/518
Date:
21 Oct 2021
Publisher:
CDS
Description:
The proper motions of OB-associations computed using the old (1997, Cat. <I/239>) and new (2008, Cat. <I/311>) reductions of the Hipparcos data are in a good agreement with each other. The Galactic rotation curve derived from the analysis of line-of-sight velocities and proper motions of OB-associations is almost flat in the 3-kpc neighborhood of the Sun. The angular rotation velocity at the solar distance is Omega_0_=31(+/-1)km/s/kpc. The standard deviation of the velocities of OB-associations from the rotation curve is sigma=7.2km/s. The distance scale for OB associations by Blaha and Humpreys (1989AJ.....98.1598B) should be shortened by 10-20%. The residual velocities of OB-associations calculated for the new and old reductions differ, on average, by 3.5km/s. The mean residual velocities of OB-associations in the stellar-gas complexes depend slightly on the data reduction employed.
23736. Velocity catalog of A545 galaxies
ID:
ivo://CDS.VizieR/J/A+A/529/A128
Title:
Velocity catalog of A545 galaxies
Short Name:
J/A+A/529/A128
Date:
21 Oct 2021
Publisher:
CDS
Description:
The mechanisms giving rise to diffuse radio emission in galaxy clusters, and in particular their connection with cluster mergers, are still debated. We seek to explore the internal dynamics of the cluster Abell 545, which has been shown to host a radio halo. Abell 545 is also peculiar for hosting in its center a very bright, red, diffuse intracluster light due to an old, presumably metal-rich stellar population, so bright to be named as "star pile". Our analysis is mainly based on redshift data for 110 galaxies acquired at the Telescopio Nazionale Galileo. We identify 95 cluster members and analyze the cluster internal dynamics by combining galaxy velocities and positions. We also use both multiband photometric data acquired at the Isaac Newton Telescope and X-ray data from the XMM-Newton Science Archive.
23737. Velocity curve of {alpha} Arietis
ID:
ivo://CDS.VizieR/J/A+A/529/A134
Title:
Velocity curve of {alpha} Arietis
Short Name:
J/A+A/529/A134
Date:
21 Oct 2021
Publisher:
CDS
Description:
To search for extra-solar planets around intermediate mass stars, we are conducting a precise RV survey around K-giants. We present high-accuracy RV measurements of alpha Ari from November 2003 to February 2010. This star belongs to our sample of 55 K-giants studied for extra-solar planet and pulsation searches using the fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) attached to the 1.8-m telescope at Bohyunsan Optical Astronomy Observatory (BOAO) in Korea. We find a planetary companion with a long-period and low-amplitude radial velocity (RV) variations in oscillating K2 III star alpha Ari (HD 12929). We do not find the correlation between RV variations and chromospheric activity indicators (CaII H & K region, H{alpha} line). The bisector analysis also shows that bisector velocity span (BVS) does not show any obvious correlation with RV variation but has periodic component that may be attributed to the rotation of the star. If the RV variation is indeed caused by a planetary companion, an orbital solution with a period of P=381-days, a semi-amplitude of K=41m/s, and an eccentricity of e=0.25 fits the data best. Assuming a possible stellar mass of M_star_=1.5M_{sun}_, we estimate the minimum mass for the planetary companion of m_2_sini=1.8M_{Jupiter}_ with an orbital semi-major axis of 1.2AU. Our finding of a likely exoplanet in alpha Ari gives a support to search for extra-solar planets around giant stars with multi-periodic oscillations.
23738. Velocity curve of {tau} Boo A
ID:
ivo://CDS.VizieR/J/A+A/578/A64
Title:
Velocity curve of {tau} Boo A
Short Name:
J/A+A/578/A64
Date:
21 Oct 2021
Publisher:
CDS
Description:
We observed the tau Boo system with the HARPS-N spectrograph in order to test a new observational strategy aimed to jointly study asteroseismology, the planetary orbit and star-planet magnetic interaction. We collected high-cadence observations on 11 nearly consecutive nights, and for each night averaged the raw FITS files using dedicated software in order to obtain high S/N spectra to study the variation of the CaII H&K lines and radial velocity values free from stellar oscillations without losing this latter information. Specific software was written to build a new custom mask used to refine the RV determination with the HARPS-N pipeline and to perform the spectroscopic analysis. We updated the planetary ephemeris and proved the acceleration due to the stellar binary companion. The study of stellar activity variation suggests the presence of an high-latitude plage during the time span of our observations. The correlation between the chromospheric activity and the planetary orbital phase remains unclear. Solar-like oscillations are detected in the radial velocity time series: we estimate asteroseismic quantities finding good agreement with theoretical predictions. With the stellar model built we find for tau Boo an age of 0.9+/-0.5Gyr, and could further constrain the value of the stellar mass to 1.38+/-0.05M_{sun}_.
23739. Velocity curves of {beta}Cnc, {mu}Leo and {beta}UMi
ID:
ivo://CDS.VizieR/J/A+A/566/A67
Title:
Velocity curves of {beta}Cnc, {mu}Leo and {beta}UMi
Short Name:
J/A+A/566/A67
Date:
21 Oct 2021
Publisher:
CDS
Description:
To investigate the low-amplitude and long-period variations in evolved stars with a precise radial velocity (RV) survey. The high-resolution, the fiber-fed Bohyunsan Observatory Echelle Spectrograph (BOES) was used from 2003 to 2013 for an RV survey of giant stars as part of the exoplanet search program at Bohyunsan Optical Astronomy Observatory (BOAO). We report the detection of three new planetary companions orbiting the K giants beta Cnc, mu Leo, and beta UMi. The planetary nature of the RV variations is supported by analyses of ancillary data. The HIPPARCOS photometry shows no variations with periods close to those in RV variations and there is no strong correlation between the bisector velocity span (BVS) and the RVs for each star. Furthermore, the stars show weak or no core reversal in Ca II H lines indicating that they are inactive stars. The companion to beta Cnc has a minimum mass of 7.8M_Jup_ in a 605-day orbit with an eccentricity of 0.08. mu Leo is orbited by a companion of minimum mass of 2.4M_Jup_ having a period of 357-days, and an eccentricity of 0.09. beta UMi is a known barium star and is suspected of harbouring a white dwarf or substellar mass companion. Its companion has a minimum mass of 6.1M_Jup_, a period of 522-days, and an eccentricity e=0.19.
23740. Velocity curves of 10 cataclysmic binaries
ID:
ivo://CDS.VizieR/J/AJ/146/107
Title:
Velocity curves of 10 cataclysmic binaries
Short Name:
J/AJ/146/107
Date:
21 Oct 2021
Publisher:
CDS
Description:
We report on ground-based optical observations of 10 cataclysmic binaries that were discovered through their X-ray emission. Time-resolved radial velocity spectroscopy yields unambiguous orbital periods for eight objects and ambiguous results for the remaining two. The orbital periods range from 87 minutes to 9.38 hr. We also obtained time-series optical photometry for six targets, four of which have coherent pulsations. These periods are 1218s for 1RXSJ045707.4+452751, 628s for AXJ1740.2-2903, 477s for AXJ1853.3-0128, and 935s for IGRJ19267+1325. A total of seven of the sources have coherent oscillations in X-rays or optical, indicating that they are intermediate polars (DQ Herculis stars). Time-resolved spectroscopy of one object, SwiftJ2218.4+1925, shows that it is an AM Herculis star, or polar, and IGRJ19552+0044 may also be in that class. For another object, SwiftJ0746.2-1611, we find an orbital period of 9.384 hr and detect the spectrum of the secondary star. The secondary's spectral contribution implies a distance of 900 (+190, -150)pc, where the error bars are estimated using a Monte Carlo technique to account for correlated uncertainties.

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