- ID:
- ivo://CDS.VizieR/J/AJ/144/114
- Title:
- Radial velocities of 6 field RR Lyrae
- Short Name:
- J/AJ/144/114
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present template radial velocity curves of ab-type RR Lyrae stars constructed from high-precision measurements of H{alpha}, H{beta}, and H{gamma} lines. Amplitude correlations between the Balmer line velocity curves, Johnson V band, and Sloan Digital Sky Survey (SDSS) g- and r-band light curves are also derived. Compared to previous methods, these templates and derived correlations reduce the uncertainty in measured systemic (center-of-mass) velocities of RR Lyrae stars by up to 15km/s, and will be of particular interest to wide-area spectroscopic surveys such as the SDSS and LAMOST Experiment for Galactic Understanding and Exploration.
Number of results to display per page
Search Results
- ID:
- ivo://CDS.VizieR/J/A+A/286/136
- Title:
- Radial velocities of four beta Cep variables
- Short Name:
- J/A+A/286/136
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- (no description available)
- ID:
- ivo://CDS.VizieR/J/A+A/415/531
- Title:
- Radial velocities of 10 Galactic Cepheids
- Short Name:
- J/A+A/415/531
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present here the appendix to the paper with the new high precision radial velocities for a sample of Galactic Cepheids. The stars are: SU Cas, EV Sct, del Cep, CV Mon, U Sgr, eta Aql, X Cyg, T Mon, RS Pup, and SV Vul.
- ID:
- ivo://CDS.VizieR/J/ApJS/156/227
- Title:
- Radial velocities of 16 Galactic Cepheids
- Short Name:
- J/ApJS/156/227
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report 490 radial velocities for 16 Galactic Cepheid variables. The typical uncertainty of a single velocity is {+/-}0.40km/s. Comparison with published velocities shows excellent agreement. Two of the Cepheids (Z Lac, S Sge) are known binaries and exhibit orbital velocity changes in our observing interval.
- ID:
- ivo://CDS.VizieR/J/A+A/460/459
- Title:
- Radial velocities of LMC RR Lyrae
- Short Name:
- J/A+A/460/459
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- All galaxies that have been adequately examined so far have shown an extended stellar halo. To search for such a halo in the LMC we have obtained low-resolution spectra for 100 LMC RR Lyrae stars, of which 87 are in the field and 13 in the clusters NGC 1835 and NGC 2019. We measured radial velocities for 87 LMC RR Lyrae stars, and metallicities for 78 RR Lyrae stars, nearly tripling the previous sample. These targets are located in 10 fields covering a wide range of distances, out to 2.5 degrees from the center of the LMC.
- ID:
- ivo://CDS.VizieR/J/MNRAS/362/1167
- Title:
- Radial velocities of 14 southern Cepheids
- Short Name:
- J/MNRAS/362/1167
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We present high-resolution spectroscopic observations and species-by-species radial velocities of a number of southern Cepheids. The stars (BP Cir, V350 Sgr, AX Cir, V636 Sco, W Sgr, S Mus, {beta} Dor, TT Aql, Y Oph, YZ Car, SW Vel, X Pup, T Mon and l Car) were observed as part of a long-term programme at Mt John University Observatory. Radial velocities were determined with the line bisector technique, and have a precision of ~300m/s. Velocity differences as large as 30km/s were found for H and Ca II when referenced to the metallic line velocity curves, but more subtle variations (of 12km/s) were also detected in many other species. Pulsational phase anticorrelations are found between lines of Si II and Ba II, confirming the propagation time delay between line-forming layers producing these two species. We find that the amplitude and phase differences between the various species increase with period.
- ID:
- ivo://CDS.VizieR/J/AJ/145/134
- Title:
- Radial velocities of 108 stars in Ruprecht 147
- Short Name:
- J/AJ/145/134
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- Ruprecht 147 is a hitherto unappreciated open cluster that holds great promise as a standard in fundamental stellar astrophysics. We have conducted a radial velocity survey of astrometric candidates with Lick, Palomar, and MMT observatories and have identified over 100 members, including 5 blue stragglers, 11 red giants, and 5 double-lined spectroscopic binaries (SB2s). We estimate the cluster metallicity from spectroscopic analysis, using Spectroscopy Made Easy (SME), and find it to be [M/H]=+0.07+/-0.03. We have obtained deep CFHT/MegaCam g'r'i'z' photometry and fit Padova isochrones to the (g'-i') and Two Micron All Sky Survey (J-K_S_) color-magnitude diagrams, using the {tau}^2^ maximum-likelihood procedure of Naylor, and an alternative method using two-dimensional cross-correlations developed in this work. We find best fits for Padova isochrones at age t=2.5+/-0.25Gyr, m-M=7.35+/-0.1, and A_V_=0.25+/-0.05, with additional uncertainty from the unresolved binary population and possibility of differential extinction across this large cluster. The inferred age is heavily dependent on our choice of stellar evolution model: fitting Dartmouth and PARSEC models yield age parameters of 3Gyr and 3.25Gyr, respectively. At ~300pc and ~3Gyr, Ruprecht 147 is by far the oldest nearby star cluster.
- ID:
- ivo://CDS.VizieR/J/AJ/132/393
- Title:
- Radial velocities of V966 Her and V1438 Aql
- Short Name:
- J/AJ/132/393
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We have examined the previously understudied Scuti stars V966 Herculis and V1438 Aquilae. We find that V966 Her is a stable pulsator with a refined period of 0.1330302 days with a full V amplitude of 0.096mag. We also find that V966 Her has an average radial velocity of +7.8km/s, a full radial velocity amplitude of 7.6km/s, and a vsini=63.8km/s. For V1438 Aql we report a revised Hipparcos period of 0.1612751 days with a full amplitude of 0.056. The average radial velocity is found to be -43km/s, with full amplitude of 9.7km/s, and a vsini=76.7km/s. Due to some anomalies seen in V1438 Aql we feel that a much larger photometric and spectroscopic campaign is required to determine the true nature of this star.
- ID:
- ivo://CDS.VizieR/J/AJ/156/231
- Title:
- Radial velocities of 2 VY Sculptoris-type CV stars
- Short Name:
- J/AJ/156/231
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We report observations of the known cataclysmic variable star (CV) V704 And, and also confirm that the optical counterpart of the ROSAT Galactic Plane Survey source RX J2338+431 is a heretofore-neglected CV. Photometric and spectroscopic observations from MDM Observatory show both systems to be nova-like variables that exhibit dips of 4-5 mag from their mean brightnesses, establishing them as members of the VY Scl subclass. From high-state emission-line radial velocities, we determine orbital periods of 0.151424(3) days (3.63 hr) for V704 And and 0.130400(1) days (3.13 hr) for RX J2338+431. In V704 And, we find that the H{alpha} emission-line measures cluster into distinct regions on a plot of equivalent width versus full width at half-maximum, which evidently correspond to high, intermediate, and low photometric states. This allows us to assign spectra to photometric states when contemporaneous photometry is not available, an apparently novel method that may be useful in studies of other novalikes. Our low-state spectra of RX J2338+431 show features of an M-type secondary star, from which we estimate a distance of 890+/-200 pc, in good agreement with the Gaia DR2 (Cat. I/345) parallax.
- ID:
- ivo://CDS.VizieR/J/AJ/155/247
- Title:
- Radial velocities of 6 X-ray cataclysmic binaries
- Short Name:
- J/AJ/155/247
- Date:
- 21 Oct 2021
- Publisher:
- CDS
- Description:
- We conducted time-resolved optical spectroscopy and/or time-series photometry of 15 cataclysmic binaries that were discovered in hard X-ray surveys by the Swift Burst Alert Telescope and the International Gamma-Ray Astrophysics Laboratory, with the goal of measuring their orbital periods and searching for spin periods. Four of the objects in this study are new optical identifications: Swift J0535.2+2830, Swift J2006.4+3645, IGR J21095+4322, and Swift J2116.5+5336. Coherent pulsations are detected from three objects for the first time, Swift J0535.2+2830 (1523 s), 2PBC J1911.4+1412 (747 s), and 1SWXRT J230642.7+550817 (464 s), indicating that they are intermediate polars (IPs). We find two new eclipsing systems in time-series photometry: 2PBC J0658.0-1746, a polar with a period of 2.38 hr, and Swift J2116.5+5336, a disk system that has an eclipse period of 6.56 hr. Exact or approximate spectroscopic orbital periods are found for six additional targets. Of note is the long 4.637-day orbit for Swift J0623.9-0939, which is revealed by the radial velocities of the photospheric absorption lines of the secondary star. We also discover a 12.76 hr orbital period for RX J2015.6+3711, which confirms that the previously detected 2.00 hr X-ray period from this star is the spin period of an IP, as inferred by Coti Zelati et al. (2016MNRAS.456.1913C). These results support the conclusion that hard X-ray selection favors magnetic CVs, with IPs outnumbering polars.
