J/AJ/162/117 Radial velocity for 19 RR Lyrae (Barnes+, 2021)
A radial-velocity search for binary RR Lyrae variables.
Barnes III T.G., Guggenberger E., Kolenberg K.
<Astron. J., 162, 117-117 (2021)>
=2021AJ....162..117B 2021AJ....162..117B (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable; Stars, double and multiple; Radial velocities;
Spectra, optical
Keywords: RR Lyrae variable stars; Binary stars
Abstract:
We report 272 radial velocities for 19 RR-Lyrae variables. For most of
the stars we have radial velocities for the complete pulsation cycle.
These data are used to determine robust center-of-mass radial
velocities that have been compared to values from the literature in a
search for evidence of binary systems. Center-of-mass velocities were
determined for each star using Fourier Series and template fits to the
radial velocities. Our center-of-mass velocities have uncertainties
from ±0.16km/s to ±2.5km/s, with a mean uncertainty of
±0.92km/s. We combined our center-of-mass velocities with values
from the literature to look for deviations from the mean
center-of-mass velocity of each star. Fifteen RR-Lyrae show no
evidence of binary motion (BK And, CI And, Z CVn, DM Cyg, BK Dra, RR
Gem, XX Hya, SZ Leo, BX Leo, TT Lyn, CN Lyr, TU Per, U Tri, RV UMa,
and AV Vir). In most cases this conclusion is reached due to the
sporadic sampling of the center-of-mass velocities over time. Three RR
Lyrae show suspicious variation in the center-of-mass velocities that
may indicate binary motion but do not prove it (SS Leo, ST Leo, and AO
Peg). TU UMa was observed by us near a predicted periastron passage
(at 0.14 in orbital phase) but the absence of additional
center-of-mass velocities near periastron makes the binary detection,
based on radial velocities alone, uncertain. Two stars in our sample
show Hγ emission in phases 0.9-1.0: SS Leo and TU UMa.
Description:
The observations were taken at the McDonald Observatory 2.1m Otto
Struve telescope at the f/13.5 Cassegrain focus with the Sandiford
Echelle Spectrometer. All spectra were taken at resolving power
R=60000 per 2pixels with a 1" slit. Most spectra covered the
wavelength region 4250-4750Å in 18 orders. (In one observing run
the spectra were shifted 50Å to the blue.)
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 91 19 Observed RR Lyrae stars
table3.dat 40 272 Radial velocities of RR Lyrae
table4.dat 44 19 New center-of-mass radial velocities
table5.dat 45 126 Historical center of mass radial velocities
refs.dat 86 31 References used
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See also:
B/gcvs : General Catalogue of Variable Stars (Samus+, 2007-2017)
II/264 : ASAS Variable Stars in Southern hemisphere (Pojmanski+, 2002-2005)
J/A+A/589/A94 : TU UMa light curves and maxima, CL Aur minima (Liska+, 2016)
J/MNRAS/459/4360 : Field RR Lyrae stars (Liska+, 2016)
J/AJ/153/96 : Standard Galactic field RRLyrae. I. Photometry (Monson+, 2017)
J/A+A/623/A116 : Galactic Cepheids & RRLyrae multiplicity. I. (Kervella+, 2019)
J/A+A/623/A117 : Galactic Cepheids & RRLyrae multiplicity. II (Kervella+, 2019)
J/ApJ/863/151 : Period analysis of 7 field RRab stars (Li+, 2018)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Star Star identifier
8- 9 I2 h RAh [1/23] Hour of right ascension (J2000)
11- 12 I2 min RAm Minute of right ascension (J2000)
14- 17 F4.1 s RAs Second of right ascension (J2000)
19 A1 --- DE- [±] Sign of declination (J2000)
20- 21 I2 deg DEd Degree of declination (J2000)
23- 24 I2 arcmin DEm Arcminute of declination (J2000)
26- 27 I2 arcsec DEs Arcsecond of declination (J2000)
29- 33 F5.2 mag Vmagmin [9.26/12.4] Minimum V-band magnitude
35- 39 F5.2 mag Vmagmax [10.2/13.5] Maximum V-band magnitude
41- 50 F10.4 d HJD [36079/56751] Time of maximum light; HJD-2400000
52- 62 F11.9 d Per [0.36/0.66] Period
64- 76 A13 --- Ref Reference used
78- 91 A14 s Tint Integration time
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Star Star
8- 17 F10.5 d HJD [6717/8391] Heliocentric Julian (mid-point)
Date; HJD-2450000
19- 23 F5.3 --- Phase [0/1] Phase, cycles
25- 32 F8.3 km/s RVel [-306/196] Heliocentric Radial velocity
35- 40 F6.3 km/s e_RVel [0.2/21] Uncertainty in RVel
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Star Star
8- 16 F9.4 d HJD [6732/8391] Heliocentric Julian Date (mean);
HJD-2450000
18- 24 F7.2 km/s RVel [-309/172] Center of mass (γ) radial velocity
26- 29 F4.2 km/s e_RVel [0.1/3]? Uncertainty in GRV
31- 44 A14 --- Type Type of Fit
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- Star Star
8- 8 A1 --- Flag Flag (1)
10- 16 I7 d JD [2422765/2458391]? Julian Date
18- 24 F7.2 km/s RVel [-380/187] Center of mass heliocentric radial
velocity
26- 30 F5.2 km/s e_RVel [0.1/47] Uncertainty in RVel
32- 38 F7.2 km/s O-C [-117/385]? Residual
40- 45 A6 --- r_RVel Reference for RVel
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Note (1): Flag as follows:
e = The JD has been estimated
w = The GRV value is the weighted mean. The JD and Residual values are sent
to null values for these rows.
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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1- 2 I2 --- Ref [1/31] Reference code
4- 22 A19 --- Autor Main autor
24- 42 A19 --- BIB BIBcode
44- 57 A14 --- Cat. Vizier catalog
59- 86 A28 --- Note Additional note
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 06-Dec-2021