J/A+A/509/A24 Radial velocity curve of γ1 Leo (Han+, 2010)
Detection of planetary companion around K0 III giant star γ1 Leonis.
Han I., Lee B.C., Kim K.M., Mkrtichian D.E., Hatzes A.P., Valyavin G.
<Astron. Astrophys. 509, A24 (2010)>
=2010A&A...509A..24H 2010A&A...509A..24H
ADC_Keywords: Stars, giant ; Planets ; Radial velocities
Keywords: stars: individual: gamma1 Leonis - planetary systems - supergiants
Abstract:
Our primary goal is to search for planets around intermediate mass
stars. We are also interested in studying the nature of radial
velocity (RV) variations of K giant stars.
We selected about 55 early K giant (K0-K4) stars brighter than fifth
magnitude that were observed using BOES, a high resolution
spectrograph attached to the 1.8m telescope at BOAO (Bohyunsan
Optical Astronomy Observatory). BOES is equipped with I2 absorption
cell for high precision RV measurements.
We detected a periodic radial velocity variations in the K0 III star
gamma1 Leo with a period of P=429-days. An orbital fit of the observed
RVs yields a period of P=429-days, a semi-amplitude of K=208m/s, and
an eccentricity of e=0.14. To investigate the nature of the RV
variations, we analyzed the photometric, Ca II λ 8662
equivalent width, and line-bisector variations of gamma1 Leo. We
conclude that the detected RV variations can be best explained by a
planetary companion with an estimated mass of msini=8.78M♃
and a semi-major axis of a=1.19AU, assuming a stellar mass of
1.23M☉.
Description:
The RV measurements obtained from May 2003 until May 2009 are listed
in Table 3.
Objects:
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RA (2000) DE Designation(s)
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10 19 58.4 +19 50 29 gamma1 Leo = HR 4057
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table3.dat 32 205 Radial velocity of gamma1 Leo
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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- 14 F14.6 --- HJD Heliocentric Julian date of the observation
15- 23 F9.4 km/s RV Radial velocity
24- 32 F9.4 km/s e_RV Standard error of RV
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Acknowledgements:
Inwoo Han,
(End) Inwoo Han [KASI, Korea], Patricia Vannier [CDS] 07-Jan-2010