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1091. Radial velocities of V966 Her and V1438 Aql
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.
1092. Radial velocities of 2 VY Sculptoris-type CV stars
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.
1093. Radial velocities of 6 X-ray cataclysmic binaries
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.
1094. Radial velocities & photometry of classical Cepheids
ID:
ivo://CDS.VizieR/J/A+A/318/416
Title:
Radial velocities & photometry of classical Cepheids
Short Name:
J/A+A/318/416
Date:
21 Oct 2021
Publisher:
CDS
Description:
Radial velocities and distances have been measured for a sample of 48 remote classical Cepheids located in the outer disc of the Galaxy (118deg<l<274deg). The distances are determined from BVI photometry, with semi-empirical metallicity corrections calibrated on the Magellanic Clouds. Using these Cepheids as tracers, the rotation curve of the disc is determined between R_0_ and 2R_0_. The result is a flat rotation curve about 30km/s lower than theta_0_, V_rot_=193+/-4km/s for R_0_==8.5kpc and theta_0_=220kms/s assumed, or V_rot_=167+/-4km/s for R_0_=8kpc and theta_0_=200km/s. The possible presence of non-axisymmetric components in the rotation of the outer disc is considered. We find a very small or vanishing value for any radial motion of the LSR or expansion/contraction motion.
1095. Radial Velocity and BIS measurements of Polaris
ID:
ivo://CDS.VizieR/J/A+A/623/A146
Title:
Radial Velocity and BIS measurements of Polaris
Short Name:
J/A+A/623/A146
Date:
21 Oct 2021
Publisher:
CDS
Description:
We investigate temporally changing variability amplitudes and the multi- periodicity of the type-I Cepheid Polaris using 162 high-precision radial velocity (RV) and bisector inverse span (BIS) measurements based on optical spectra recorded using Hermes at the 1.2m Flemish Mercator telescope on La Palma, Canary Islands, Spain. Using an empirical template fitting method, we show that Polaris' RV amplitude has been stable to within ~30m/s between September 2011 and November 2018. We apply the template fitting method to publicly accessible, homogeneous RV data sets from the literature and provide an updated solution of Polaris' eccentric 29.3yr orbit. While the inferred pulsation-induced RV amplitudes differ among individual data sets, we find no evidence for time-variable RV amplitudes in any of the separately considered, homogeneous data sets. Additionally, we find that increasing photometric amplitudes determined using SMEI photometry are likely spurious detections due to as yet ill-understood systematic effects of instrumental origin. Given this confusing situation, further analysis of high-quality homogeneous data sets with well-understood systematics is required to confidently establish whether Polaris' variability amplitude is subject to change over time. We confirm periodic bisector variability periods of 3.97d and 40.22d using Hermes BIS measurements and identify a third signal at a period of 60.17d. Although the 60.17d signal dominates the BIS periodogram, we caution that this signal may not be independent of the 40.22d signal. Finally, we show that the 40.22d signal cannot be explained by stellar rotation. Further long-term, high-quality spectroscopic monitoring is required to unravel the complete set of Polaris' periodic signals, which has the potential to provide unprecedented insights into the evolution of Cepheid variables.
1096. Radial velocity curve of {gamma} Peg
ID:
ivo://CDS.VizieR/J/A+A/469/1069
Title:
Radial velocity curve of {gamma} Peg
Short Name:
J/A+A/469/1069
Date:
21 Oct 2021
Publisher:
CDS
Description:
With this work we provide observational material to study magnetic field variability of the classical beta Cep-type star gamma Peg. The observations were carried out in the HeI 6678 line in the course of 23 observing nights from 1997 to 2005 with using coude spectrograph in spectropolarimetric mode at the Crimean 2.6m telescope. The behavior of stellar wind was studied in the UV region using data from the IUE satellite (the INES database). It is shown that the UV stellar wind exhibits a variability. A variation of the wind due to stellar pulsations has been detected. In the HeI 6678 line the abnormally blueshifted radial velocities (gamma=-60.57+/-0.29km/s) were detected during a single night in 2005. We do not confirm the 370.5-day orbital period. The most probable orbital period was estimated as P_orb_=6.81608+/-0.00012d. The ratio P_orb_/P_puls_=44.92 appeared to be very close to integer. We have detected the presence of weak magnetic field on the star. The longitudinal component of the field varies from -10G to 30G with the stellar rotation. The most probable rotational period is P_rot_=6.6538+/-0.0016d. Both the orbital and the rotational periods are integral multiple of the difference between them: P_orb_/|P_orb_-P_rot_|=42.002, and P_rot_/|P_orb_-P_rot_|=41.002. Variation of the longitudinal magnetic field during pulsation period with an amplitude about 7G has been detected.
1097. Radial velocity curve of RBS 490
ID:
ivo://CDS.VizieR/J/PASP/118/1238
Title:
Radial velocity curve of RBS 490
Short Name:
J/PASP/118/1238
Date:
21 Oct 2021
Publisher:
CDS
Description:
RBS (ROSAT Bright Source) 0490 is a cataclysmic variable star (CV) with unusually strong emission lines. The strength of the emission lines has led to a suggestion that the object is intrinsically faint and correspondingly nearby (33pc), which, if true, would strongly affect estimates of the CV space density. Here we report astrometry, filter photometry, and time-series spectroscopy of this object. The astrometry gives an absolute parallax of 4.5+/-1.5mas and a relative proper motion of 102mas/yr. A Bayesian procedure gives a very uncertain distance estimate of d~300pc, and the small parallax alone implies d>133pc (at 2 standard deviations). The mean V magnitude is 17.4, which implies M_V_=10.9-5log[d/(200pc)], neglecting extinction. At 200pc, the space velocity would be over 90km/s with respect to the local standard of rest. The time-series spectroscopy shows a possible emission-line radial velocity period near 46 minutes. This would be unusually short for an orbital period, and it may represent some other clock in the system.
1098. Radial velocity curve of Sigma Gem
ID:
ivo://CDS.VizieR/J/A+AS/123/209
Title:
Radial velocity curve of Sigma Gem
Short Name:
J/A+AS/123/209
Date:
21 Oct 2021
Publisher:
CDS
Description:
The table contains the radial velocities of the RS CVn star sigma Geminorum measured by cross-correlation using Beta Oph as template from the high-resolution SOFIN spectra around 6175A.
1099. Radial velocity curve of V440 Per
ID:
ivo://CDS.VizieR/J/MNRAS/396/2194
Title:
Radial velocity curve of V440 Per
Short Name:
J/MNRAS/396/2194
Date:
21 Oct 2021
Publisher:
CDS
Description:
440 Per is a Population I Cepheid with a period of 7.57d and low-amplitude, almost sinusoidal light and radial velocity curves. With no reliable data on the first harmonic, its pulsation mode identification remained controversial. We obtained a radial velocity curve of V440 Per with our new high-precision and high-throughput Poznan Spectroscopic Telescope.
1100. Radial velocity curves of 11 Cepheids
ID:
ivo://CDS.VizieR/J/A+A/622/A164
Title:
Radial velocity curves of 11 Cepheids
Short Name:
J/A+A/622/A164
Date:
21 Oct 2021
Publisher:
CDS
Description:
We present the results of the study of Galactic binary Cepheids combining interferometric and spectroscopic observations. For this purpose, we performed new spectroscopic observations to obtain high-precision radial velocity measurements of the Cepheids (primary component of the systems). We then fit the radial pulsation and orbital velocities to obtain the orbital elements.