J/AJ/152/226 Radial velocities of 35 cataclysmic variables (Thorstensen+, 2016)
A trip to the cataclysmic binary zoo: detailed follow-up of 35 recently
discovered systems.
Thorstensen J.R., Alper E.H., Weil K.E.
<Astron. J., 152, 226-226 (2016)>
=2016AJ....152..226T 2016AJ....152..226T (SIMBAD/NED BibCode)
ADC_Keywords: Stars, variable ; Binaries, cataclysmic ; Novae ;
Radial velocities
Keywords: novae, cataclysmic variables - stars: dwarf novae
Abstract:
We report follow-up studies of 35 recently discovered cataclysmic
variables (CVs), 32 of which were found in large, automated synoptic
sky surveys. The objects were selected for observational tractability.
For 34 of the objects, we present mean spectra and spectroscopic
orbital periods, and for one more we give an eclipse-based period.
Thirty-two of the period determinations are new, and three of these
refine published estimates based on superhump periods. The remaining
three of our determinations confirm previously published periods.
Twenty of the stars are confirmed or suspected dwarf novae with
periods shorter than 3 hr, but we also find three apparent polars (AM
Her stars) and six systems with P>5hr. Five of these systems have
secondary stars visible in their spectra, from which we estimate
distances when possible. The orbital period distribution of this
sample is very similar to that of previously discovered CVs.
Description:
We present spectroscopic follow-up observations of 35 newly discovered
cataclysmic variables (CVs), 32 of which were found by the Catalina
Real Time Transient Surveys (CRTS; Drake et al. 2009, Cat.
J/ApJ/696/870; Drake et al. 2014, Cat. J/MNRAS/441/1186; Breedt et al.
2014, Cat. J/MNRAS/443/3174), ASAS-SN (Shappee et al.
2014ApJ...788...48S 2014ApJ...788...48S), and/or MASTER (Lipunov et al.
2010AdAst2010E..30L 2010AdAst2010E..30L).
All our observations are from Michigan-Dartmouth-MIT (MDM) Observatory
on Kitt Peak, Arizona.
For nearly all the spectra, we used the "modspec" spectrograph (a
description of the modspec can be found at
http://mdm.kpno.noao.edu/Manuals/ModSpec/modspec_man.html) with a
600line/mm grating. We mostly used a SITe 20482 CCD detector, which
yielded 2Å/pixel from 4210 to 7500Å, with declining throughput
toward the ends of the spectral range. When this detector was
unavailable, we used a very similar 10242 SITe detector
("Templeton"), which covered 4660 to 6730Å. The modspec was mounted
mostly on the 2.4m Hiltner telescope, but for some of the brighter
objects, we used the 1.3m McGraw-Hill telescope. For a few of the 1.3m
spectra, we used the Mark III grism spectrograph, which covered 4580
to 6850Å at 2.3Å/pixel. On both telescopes and with both
spectrographs, we used an Andor Ikon camera to view the reflective
slit jaws through a microscope and guided the telescope with a
separate off-axis guider. With this arrangement we could place any
object that was bright enough for a usable spectrum in the slit and
track it accurately even if the portion of the light spilling onto the
slit jaws was invisible.
Our emission-line radial velocities are almost entirely of Hα,
since it almost always gives the best signal-to-noise ratio with our
instrument.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 77 35 List of objects
table2.dat 42 1441 Radial velocities
table3.dat 84 39 Fits to radial velocities
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See also:
B/cb : Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2014)
I/329 : URAT1 Catalog (Zacharias+ 2015)
I/317 : The PPMXL Catalog (Roeser+ 2010)
I/284 : The USNO-B1.0 Catalog (Monet+ 2003)
J/AJ/150/170 : Radial velocities of 7 cataclysmic binaries (Halpern+, 2015)
J/MNRAS/443/3174 : 72 faint CV candidates in CRTS (Breedt+, 2014)
J/MNRAS/441/1186 : Cataclysmic variables from CRTS (Drake+, 2014)
J/ApJS/213/9 : Catalina Surveys periodic variable stars (Drake+, 2014)
J/AJ/146/107 : Velocities of 10 cataclysmic binaries (Thorstensen+, 2013)
J/AJ/144/81 : Spectroscopy and photometry of CV cand. (Thorstensen+, 2012)
J/AJ/142/181 : CVs from SDSS. VIII. The final year (Szkody+, 2011)
J/ApJ/696/870 : Catalina Real-time Transient Survey (CRTS) (Drake+, 2009)
J/AJ/134/185 : Cataclysmic variables from SDSS-DR5 (Szkody+, 2007)
J/AJ/126/3017 : Distances of Cataclysmic variables (Thorstensen, 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 12 A12 --- Name Abbreviated star name
14- 39 A26 --- OName Other name (star full name)
41- 42 I2 h RAh Hour of Right Ascension (J2000) (1)
44- 45 I2 min RAm Minute of Right Ascension (J2000) (1)
47- 51 F5.2 s RAs Second of Right Ascension (J2000) (1)
53 A1 --- DE- Sign of the Declination (J2000)(1)
54- 55 I2 deg DEd Degree of Declination (J2000) (1)
57- 58 I2 arcmin DEm Arcminute of Declination (J2000) (1)
60- 63 F4.1 arcsec DEs Arcsecond of Declination (J2000) (1)
65- 77 A13 --- Type Type notation (2)
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Note (1): Coordinates are for the most part from SDSS or the PPMXL (Roeser et
al. 2010, Cat. I/317) catalog.
Note (2): Object subtype is defined as follows:
UG = U Gem star, or dwarf nova, with a colon indicating that this
is uncertain because outbursts have not been reported;
UG(SU) = U Gem star in the period range in which superhumps may be
expected, but for which they have not been reported;
UGSU = SU UMa star with a measured superhump period;
UG:(WZ?) = Apparently slow mass transfer dwarf nova without reported
outbursts;
UG:(ZC?) = Possible Z Cam-type dwarf nova;
Polar = AM Her star;
PM = Significant proper motion;
2ndary = Secondary star detected in spectrum;
ecl = Eclipses are detected.
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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- 12 A12 --- Name Abbreviated star name (see Table 1)
14- 25 F12.4 d BJD Barycentric Julian Date of mid-exposure
in base UTC
27- 30 I4 km/s RVe [-571/466]? Emission-line radial velocity;
mostly of Hα (Vemn)
32- 34 I3 km/s e_RVe [2/208]? 1σ uncertainty in RVe
36- 39 I4 km/s RVa [-222/266]? Absorption-line radial
velocity (Vabs)
41- 42 I2 km/s e_RVa [10/42]? 1σ uncertainty in RVa
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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- 12 A12 --- Name Abbreviated star name (see Table 1)
14- 19 A6 --- f_Name Fit flag ([abs.], [emn.], or alt:) (1)
21- 30 F10.4 d T0 Epoch in Heliocentric Julian Date (HJD-2400000) (2)
32- 37 F6.4 d e_T0 Uncertainty in T0
39- 49 F11.9 d Per [0.057/0.38]? Period (3)
51- 61 F11.9 d e_Per [0/0.002]? Uncertainty in Per
63 A1 --- f_Per [c-h] Flag on Per (c, d, e, f, g, or h) (4)
65- 67 I3 km/s K [22/320] Semi-amplitude (3)
69- 70 I2 km/s e_K [3/21] Uncertainty in K
72- 74 I3 km/s gamma [-75/52] Systemic velocity γ (3)
76- 77 I2 km/s e_gamma [2/14] Uncertainty in γ
79- 81 I3 --- Nsp [13/115] Number of spectra used in fit
83- 84 I2 km/s rms [10/62] RMS fit residual (σ)
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Note (1): Fit flag on radial velocity is defined as follows:
[abs.] = Fit to absorption line radial velocities;
[emn.] = Fit to emission line radial velocities;
alt: = Alternative fit for ASAS-SN 15dl that corresponds to a daily
cycle-count period alias near 7.14 hours.
Note (2):
Parameters of least-squares sinusoid fits to the RVs, of the form:
v(t)=γ+Ksin(2π(t-T0)/Per).
The epoch, T0, is chosen to be near the center of the time interval covered
by the data, and within one cycle of an actual observation.
Note (3): Parameters of least-squares sinusoid fits to the RVs, of the form:
v(t)=γ+Ksin(2π(t-T0)/Per).
Note (4): Flag on period is defined as follows:
c = Period given is the weighted mean of periods from separate fits to the
velocities from the individual observing runs;
d = Period fixed at value derived from eclipses;
e = For both the absorption and emission fits, the period was held fixed
at the value derived from the ellipsoidal variations in the archival
Catalina Real Time Transient Surveys (CRTS; Drake et al. 2009,
Cat. J/ApJ/696/870; Drake et al. 2014, Cat. J/MNRAS/441/1186;
Breedt et al. 2014, Cat. J/MNRAS/443/3174) light curve;
f = Period fixed at the value derived from the archival CRTS light curve;
g = Period for emission held fixed at the value derived from the absorption
lines;
h = Period was fixed at the weighted mean of the absorption- and
emission- line periods.
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History:
From electronic version of the journal
(End) Prepared by [AAS]; Sylvain Guehenneux [CDS] 06-Feb-2017