J/MNRAS/395/593 ASAS chromospherically active eclipsing binaries (Parihar+ 2009)
Spectroscopic survey of ASAS eclipsing variables:
search for chromospherically active eclipsing binary stars. I.
Parihar P., Messina S., Bama P., Medhi B.J., Muneer S., Velu C., Ahmad A.
<Mon. Not. R. Astron. Soc., 395, 593-607 (2009)>
=2009MNRAS.395..593P 2009MNRAS.395..593P
ADC_Keywords: Binaries, eclipsing ; Photometry, infrared ;
MK spectral classification
Keywords: stars: activity - binaries: close - stars: emission-line, Be -
stars: individual: HD 89620 - stars: late-type
Abstract:
We have started a spectroscopic survey to identify new
chromospherically active components and low-mass pre-main sequence
(PMS) stars in recently discovered All Sky Automated Survey (ASAS)
eclipsing binaries. In this paper, we briefly describe our scientific
motivation, the observing tools and the results obtained from the
first phase of this survey. Using the available observing facilities
in India, the spectroscopic observations of a sample of 180 candidate
eclipsing binary stars selected from ASAS-I&II releases were carried
out during 2004-2006. The strength of Halpha emission was used to
characterize the level of chromospheric activity. Our spectroscopic
survey reveals that out of 180 stars about 36 binary systems show
excess Halpha emission. One of the objects in our sample, ASAS
081700-4243.8, displays very strong Halpha emission. Follow-up
high-resolution spectroscopic observations reveal that this object is
indeed very interesting and most likely a classical Be-type system
with K0III companion.
Description:
The medium-resolution spectroscopic survey of our 180 ASAS stars was
carried out using the 2-m Himalayan Chandra Telescope (HCT) of Indian
Astronomical Observatory (IAO) equipped with the Himalaya Faint Object
Spectrograph (HFOSC) spectrograph and the 2.3-m Vainu Bappu Telescope
(VBT) of Vainu Bappu Observatory (VBO) equipped with the Optomechanics
Research (OMR) spectrograph.
High-resolution optical spectra of one particularly interesting target
HD 69820 (ASAS 081700-4243.8) were obtained with two different
instruments: the fibre-fed coude echelle spectrometer of the 2.3-m VBT
and University College London Echelle Spectrograph (UCLES) at the 4-m
Anglo-Australian Telescope (AAT) of Anglo-Australian Observatory (AAO).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 153 180 Log of medium resolution spectra collected from
HCT and VBT telescopes
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/264 : ASAS Variable Stars in Southern hemisphere (Pojmanski+, 2002-05)
J/AcA/48/35 : All Sky Automated Survey variable stars (Pojmamski 1998)
J/AcA/50/177 : All Sky Automated Survey Catalog (Pojmanski+, 2000)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- Seq Sequential number
5- 17 A13 --- ASAS Star name (HHMMSS+DDMM.m) (4)
19- 21 A3 --- Tel Telescope (1)
23- 32 A10 "YYYY-MM-DD" ObsDate Date of observation
34- 37 I4 s ExpTime Exposure time
39- 42 F4.2 --- AirM Air mass
44- 51 F8.4 d Per Orbital period
53- 59 F7.2 d Epoch Epoch of observation (MHD=HJD-2450000)
61- 65 F5.2 mag Vmax Brightest V magnitude
67- 70 F4.2 mag Vamp Amplitude in V band
72- 75 F4.2 mag V-J V-J colour index
77- 80 F4.2 mag V-H V-H colour index
82- 85 F4.2 mag V-K V-K colour index
87- 90 F4.2 mag J-H J-H colour index
92- 95 F4.2 mag H-K H-K colour index
97-101 F5.3 --- phi ?=- Orbital phase at which the 2MASS
photometry was made
103-105 A3 --- n_phi Note on the epoch of 2MASS photometry (2)
107-112 A6 --- Etype Eclipsing type (3)
114 A1 --- X [X] if X-ray emission
116-153 A38 --- SpType MK spectral types
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Note (1): Telescope is hct or vbt:
hct = 2-m Himalayan Chandra Telescope of Indian Astronomical
Observatory, equipped with the Himalaya Faint Object
Spectrograph (HFOSC) spectrograph
vbt = 2.3-m Vainu Bappu Telescope of Vainu Bappu Observatory,
equipped with the Optomechanics Research (OMR) spectrograph
Note (2): Note as follows:
ooe = out of eclipse
inI = at primary minimum
iII = at secondary minimum,
imi = primary and secondary minimum of similar depth
x = indicate that 2MASS observations were made close to the
beginning/end phases of minimum
Note (3): eclipsing variables classified as Contact (EC),
semi-detached (ESD) or detached (ED); or miscellaneous (MISC).
Note (4): this name was truncated to HHMMSS+DDMM in the published
table; the fraction of acrmin in the declination was added at
CDS from a comparison with the ASAS catalog (II/264)
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History:
* 14-Sep-2009: From electronic version of the journal
* 24-Nov-2009: ASAS name corrected (was truncated in the published
table, see the "Note (4)" section above.
(End) Patricia Vannier [CDS] 14-Sep-2009