J/AJ/150/170 Radial velocities of 7 cataclysmic binaries (Halpern+, 2015)
Optical studies of 13 hard X-ray selected cataclysmic binaries from the
Swift-BAT survey.
Halpern J.P., Thorstensen J.R.
<Astron. J., 150, 170 (2015)>
=2015AJ....150..170H 2015AJ....150..170H (SIMBAD/NED BibCode)
ADC_Keywords: Binaries, cataclysmic ; Binaries, X-ray ; Radial velocities
Keywords: novae, cataclysmic variables - X-rays: binaries
Abstract:
From a set of 13 cataclysmic binaries that were discovered in the
Swift Burst Alert Telescope (BAT) survey, we conducted time-resolved
optical spectroscopy and/or time-series photometry of 11, with the
goal of measuring their orbital periods and searching for spin
periods. Seven of the objects in this study are new optical
identifications. Orbital periods are found for seven targets, ranging
from 81 minutes to 20.4hr. PBC J0706.7+0327 is an AM Herculis star
(polar) based on its emission-line variations and large amplitude
photometric modulation on the same period. Swift J2341.0+7645 may be a
polar, although the evidence here is less secure. Coherent pulsations
are detected from two objects, Swift J0503.7-2819 (975s) and Swift
J0614.0+1709 (1412s and 1530s, spin and beat periods, respectively),
indicating that they are probable intermediate polars (DQ Herculis
stars). For two other stars, longer spin periods are tentatively
suggested. We also present the discovery of a 2.00hr X-ray modulation
from RX J2015.6+3711, possibly a contributor to Swift J2015.9+3715,
and likely a polar.
Description:
Our instrumentation, and reduction and analysis procedures are
essentially identical to those described in Paper I (Thorstensen et
al. 2013, cat. J/AJ/146/107). All of our optical data are from the MDM
Observatory (http://mdm.kpno.noao.edu/index/Instrumentation.html),
which comprises the 1.3m McGraw-Hill telescope and the 2.4m Hiltner
telescope, both on the southwest ridge of Kitt Peak, Arizona. With a
single exception, the radial velocity studies to search for the
orbital periods were done on the 2.4m, while high-cadence photometry
sensitive to spin periods was carried out on the 1.3m.
All of our radial velocity studies used the modular spectrograph, as
described in Paper I (Thorstensen et al. 2013, cat. J/AJ/146/107).
Most of our velocities are from the the 2.4m telescope. Some spectra
of Swift J2124.6+0500, and all the data we used for Swift
J0939.7-3224, are from the McGraw-Hill 1.3m telescope, again with the
modular spectrograph. For four newly identified objects we have only
single spectra that were obtained on two observing runs on the 2.4m.
These used the Boller and Chivens CCD spectrograph (CCDS) and the Ohio
State Multi-Object Spectrograph (OSMOS). Descriptions of these
instruments can be found on the MDM Observatory web page
(http://mdm.kpno.noao.edu/index/Instrumentation.html).
The objects observed are listed in Table1. Table2 lists the radial
velocity data, and Table3 gives parameters of the best-fit sinusoids.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 77 14 Stars observed
table2.dat 54 415 Radial velocities
table3.dat 81 9 Fits to radial velocities
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See also:
B/cb : Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2014)
II/336 : AAVSO Photometric All Sky Survey (APASS) DR9 (Henden+, 2016)
V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)
I/322 : UCAC4 Catalogue (Zacharias+, 2012)
I/317 : The PPMXL Catalog (Roeser+ 2010)
I/284 : The USNO-B1.0 Catalog (Monet+ 2003)
J/AJ/149/128 : Radial velocities of 29 CVs (Thorstensen+, 2015)
J/AJ/146/107 : Velocity curves of 10 cataclysmic binaries (Thorstensen+, 2013)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- Name Stellar identifier
20- 21 I2 h RAh Hour of Right Ascension (J2000) (1)
23- 24 I2 min RAm Minute of Right Ascension (J2000) (1)
26- 30 F5.2 s RAs Second of Right Ascension (J2000) (1)
32 A1 --- DE- Sign of the Declination (J2000) (1)
33- 34 I2 deg DEd Degree of Declination (J2000) (1)
36- 37 I2 arcmin DEm Arcminute of Declination (J2000) (1)
39- 42 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1)
44- 47 F4.1 mag Vmag [12.7/18.9] Approximate V band magnitude
49 A1 --- r_Vmag [ABDS] Reference for Vmag (2)
51- 55 A5 --- Data [ISTX, ] Type of data presented here (3)
57- 59 A3 --- Class Classification of star (4)
61- 67 F7.2 s Per ? Period (presumed to be the spin period)
69- 73 F5.2 s e_Per ? Uncertainty in Period
75 A1 --- f_Per [f?] Flag on Per (f=or possibly its 1 day alias,
1390.2s. A beat period of 1530s is also detected)
77 I1 --- r_Per ? Reference for Per (5)
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Note (1): Coordinates are for J2000.0 (ICRS), either from the PPMXL catalog
(Roeser et al. 2010, cat. I/317), the Sloan Digital Sky Survey (Alam et al.
2015ApJS..219...12A 2015ApJS..219...12A; see the DR9 in cat. V/139), or derived from
astrometric fits to our own images. Estimated uncertainty is ±0.2''.
Note (2): Reference code defined as below:
S = Our spectrophotometry;
D = Our direct image;
A = APASS (Henden et al., 2012JAVSO..40..430H 2012JAVSO..40..430H; see DR9 in cat. II/336), as
listed in the UCAC4 (Zacharias et al. 2013, cat. I/322);
B = Interpolated from Schmidt-plate magnitudes in USNO B1.0 (Monet et al.
2003, cat. I/284).
Note (3): Type of data defined as follows:
I = Optical spectroscopic identification;
S = Time-resolved spectroscopy;
T = Time-series photometry;
X = X-ray light curve.
Note (4): Classification code defined as follows:
N = Novalike variable (pulsations not confirmed);
DQ = DQ Her star or IP (evidence for pulsations);
AM = AM Her star or polar.
Note (5): Reference code defined as follows:
1 = This paper;
2 = Bernardini et al. (2015MNRAS.453.3100B 2015MNRAS.453.3100B);
3 = This paper, X-ray.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 18 A18 --- Name Stellar identifier
20- 32 F13.4 d BJD Barycentric Julian Date (of mid-integration on
the UTC system)
34- 37 I4 km/s RV [-348/341] Radial velocity
39- 40 I2 km/s e_RV [1/79] The 1σ uncertainty in RV
42- 47 A6 "h:m" HA Hour and minute of Hour Angle (at the start of
the exposure)
49- 52 I4 s Exp [180/1200] Exposure time
54 A1 --- Tel [HM] Telescope (M=McGraw-Hill 1.3m, H=Hiltner 2.4m)
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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- 18 A18 --- Name Stellar identifier
20 A1 --- f_Name [cde] Flag on Name (1)
22- 31 F10.4 d T0 Heliocentric Julian Date T0 (HJD-2400000) (4) (2)
33- 38 F6.4 d e_T0 Error in T0
40- 48 F9.7 d Per Spectroscopic period Pspec (4)
50- 58 F9.7 d e_Per Error in Per
60 A1 --- f_Per [f] Flag on Per (3)
62- 64 I3 km/s K The K parameter (semi-amplitude) (4)
66- 67 I2 km/s e_K Error in K
69- 71 I3 km/s gamma The γ parameter (systemic velocity) (4)
73- 74 I2 km/s e_gamma Error in gamma
76- 78 I3 --- N Number of spectra used
80- 81 I2 km/s rms Root-mean-square residual of the fit σ
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Note (1): Flag defined as follows:
c = The two periods reflect different choices of daily cycle count over
a 5-day gap, and the excessively precise periods tabulated here reflect
in turn an arbitrary choice of cycle count between observing runs. For
each choice of daily cycle count, the uncertainty in the gross period
is ∼9*10-5 days. See Section 3.1 for details;
d = Fit to velocities from 2015 March only;
e = Velocities are from HeI emission; the daily cycle count is uncertain.
Note (2): The epoch is chosen to be near the center of the time interval covered
by the data, and whithin one cycle of an actual observation.
Note (3): f=The daily cycle count is reasonably secure, but there is an
ambiguity at the scale of 1 cycle per 57 days.
Note (4): Parameters of least-squares fits to the radial velocities, of the form
v(t)=γ+Ksin[2π(t-T0)/Psepc].
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History:
From electronic version of the journal
References:
Thorstensen & Halpern, Paper I 2013AJ....146..107T 2013AJ....146..107T, cat. J/AJ/146/107
Halpern et al., Paper III 2018AJ....155..247H 2018AJ....155..247H
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 19-Apr-2016