J/AJ/147/1 Spectroscopy and photometry of HP Aur (Lacy+, 2014)
Absolute properties of the triple star HP Aurigae.
Lacy C.H.S., Torres G., Wolf M., Burks C.L.
<Astron. J., 147, 1 (2014)>
=2014AJ....147....1L 2014AJ....147....1L
ADC_Keywords: Binaries, eclipsing ; Radial velocities ; Photometry
Keywords: binaries: eclipsing - binaries: spectroscopic -
stars: fundamental parameters - stars: individual: HP Aur
Abstract:
New photometric, spectroscopic, and eclipse timing observations of the
eclipsing binary star HP Aur allow for very accurate orbital
determinations, even in the presence of a third body and transient
starspot activity. The eclipsing binary masses are determined to an
accuracy of ±0.4% and the radii to ±0.6%. The masses are
0.9543±0.0041 and 0.8094±0.0036 solar masses, and the radii are
1.0278±0.0042 and 0.7758±0.0034 solar radii, respectively. The
orbital period in the outer orbit is accurately determined for the
first time: 4.332±0.011yr. A comparison with current theories of
stellar evolution shows that the components' absolute properties can
be well-matched by the current models at an age of about 7 billion
years.
Description:
Published times of minimum light, as well as our own new dates, are
listed in Table1. Only photoelectric or CCD results are given. Our new
previously unpublished dates of minima come from three observatories
in the Czech Republic: Ondrejov (Ondrejov Observatory, Czech Republic:
0.65m reflecting telescope with an SBIG ST-8 or Apogee AP7p CCD camera
and Johnson R filter), Ostrava (Observatory and Planetarium of Johann
Palisa, Ostrava, Czech Republic: 0.20m or 0.30m telescopes with an
SBIG ST-8XME CCD camera and Johnson R filter), and ValMez (Valasske
Mezirici Observatory, Czech Republic: 0.30m Celestron Ultima telescope
with an SBIG ST-7 CCD camera and Johnson VRI filters).
HP Aur was observed spectroscopically at the Harvard-Smithsonian
Center for Astrophysics (CfA) with an echelle instrument ("Digital
Speedometer") attached to the 1.5m Tillinghast reflector at the Fred
L. Whipple Observatory (Mount Hopkins, AZ). A total of 27 exposures
were gathered between 2002 September and 2007 January with a resolving
power of R∼35000.
Differential photometry was produced from images taken by two
independent robotic telescopes.
The URSA WebScope is built from a Meade 10 inch f/6.3 LX-200 telescope
with a Santa Barbara Instruments Group ST8 CCD camera inside a
Technical Innovations Robo-Dome. The observatory is located atop
Kimpel Hall on the Fayetteville, Arkansas campus. Exposures of 120s
through a Bessel V filter. HP Aur was observed by URSA from 2001
November 22 to 2010 September 23.
The other telescope we used is the NFO WebScope, a refurbished 24inch
Group 128 Cassegrain reflector with a 2K*2K Kodak CCD camera, located
near Silver City, NM. Observations consisted of 120s exposures through
a Bessel V filter. HP Aur was observed from 2005 January 29 to 2008
February 27.
Objects:
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RA (ICRS) DE Designation(s) (Period)
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05 10 21.78 +35 47 46.6 HP Aurigae = HD 280603 (P=1.422819805)
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File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 26 184 Dates of minimum light for HP Aur
table2.dat 42 27 CfA (Harvard-Smithsonian Center for
Astrophysics) radial velocities of HP Aur
table4.dat 25 6774 URSA differential photometry of HP Aur
(URSA WebScope at Kimpel Observatory, Arkansas)
table5.dat 25 2473 NFO differential photometry of HP Aur
(NFO WebScope near Silver City, New Mexico)
refs.dat 160 47 References
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See also:
V/128 : Chromospherically Active Binaries. Third version (Eker+, 2008)
B/gcvs : General Catalogue of Variable Stars (Samus+ 2007-2013)
B/sb9 : 9th Catalogue of Spectroscopic Binary Orbits (Pourbaix+ 2004-2013)
J/AJ/144/167 : Photometry and spectroscopy of CF Tauri (Lacy+, 2012)
J/AJ/142/185 : Properties of the eclipsing binary stars HY Vir (Lacy+, 2011)
J/AJ/139/2347 : CO And Vr light curves and RV curve (Lacy+, 2010)
J/AJ/130/2838 : Velocity and light curves of RW Lac (Lacy+, 2005)
J/AJ/128/1340 : Properties of the EB star V459 Cas (Lacy+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 I1 --- Type [12] Type of eclipse (1 or 2) (1)
3- 13 F11.5 d HJD Heliocentric Julian Date (HJD-2400000)
15 A1 --- f_HJD [b] These dates were omitted from the final
orbital fit due to very bad residuals
17- 23 F7.5 d e_HJD [0/0.003] Precision in HJD
25- 26 I2 --- r_HJD [1/47] Reference (in refs.dat file)
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Note (1): Eclipses of type 1 are the deeper eclipses when the hotter, more
massive component (star 1) is being eclipsed by the cooler, less massive
component (star 2).
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Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 10 F10.4 d HJD [52532/54108] Heliocentric Julian Date
(HJD-2400000)
12- 17 F6.2 km/s RV1 Primary radial velocity
19- 25 F7.2 km/s RV2 Secondary radial velocity
27- 30 F4.2 km/s e_RV1 Uncertainty in RV1
32- 35 F4.2 km/s e_RV2 Uncertainty in RV2
37- 42 F6.4 --- Phase [0/1] Phase in the inner orbit (1)
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Note (1): As computed from the ephemeris in Table3 (see the paper).
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Byte-by-byte Description of file: table[45].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 F7.5 --- Phase [0/1] Orbital phase
9- 13 F5.3 mag DVmag Differential V band magnitude (1)
15- 25 F11.5 d HJD [52235/55463] Heliocentric Julian Date
(HJD-2400000)
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Note (1): The NFO differential magnitudes (variable-comparisons) are referenced
to the magnitude corresponding to the sum of the flux of two comparison stars.
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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 Reference identifier
4- 22 A19 --- BibCode Bibliographic code
24- 40 A17 --- Aut Author's name
42-160 A119 --- Com Comment
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Sylvain Guehenneux [CDS] 25-Aug-2014