J/A+A/556/A126 GJ667C Doppler and activity measurements (Anglada-Escude+, 2013)
A dynamically-packed planetary system around GJ 667C with three super-Earths in
its habitable zone.
Anglada-Escude G., Tuomi, M., Gerlach E., Barnes, R., Heller R.,
Jenkins J.S, Wende S., Vogt S.S., Butler R.P., Reiners A., Jones H.R.A.
<Astron. Astrophys. 556, A126 (2013)>
=2013A&A...556A.126A 2013A&A...556A.126A
ADC_Keywords: Stars, double and multiple ; Planets ; Radial velocities
Keywords: tecnhiques: radial velocities - methods: data analysis -
planets and satellites: dynamical evolution and stability -
astrobiology - stars: individual : GJ 667C
Abstract:
Since low-mass stars have low luminosities, orbits at which liquid
water can exist on Earth-sized planets are relatively close-in, which
produces Doppler signals that are detectable using state-of-the-art
Doppler spectroscopy.
GJ 667C is already known to be orbited by two super-Earth candidates.
We have recently applied developed data analysis methods to
investigate whether the data supports the presence of additional
companions.
We obtain new Doppler measurements from HARPS extracted spectra and
combined them with those obtained from the PFS and HIRES
spectrographs. We used Bayesian and periodogram-based methods to
re-assess the number of candidates and evaluated the confidence of
each detection. Among other tests, we validated the planet candidates
by analyzing correlations of each Doppler signal with measurements of
several activity indices and investigated the possible quasi-periodic
nature of signals.
Description:
HARPS-TERRA Doppler and activity measurements of GJ 667C. Doppler
Measurements are in the Barycenter of the Solar System and corrected
for perspective acceleration. The median has been velocity has been
subtracted for cosmetic purposes. Nominal uncertainties in FWHM and
BIS are 2.0 and 2.35 times the corresponding UNCCCF. No consistent
CCF measurement could be obtained for the last two spectra because of
conflicting HARPS-DRS software versions (different binary masks) used
to produce them. Except for those two spectra and according to the ESO
archive documentation, all CCF measurements were generated using the
default M2 binary mask.
Objects:
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RA (2000) DE Designation(s)
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17 18 58.84 -34 59 48.6 GJ 667C = LHS 443
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablec2.dat 67 173 Doppler and activity time-series of GJ 667C as
derived from HARPS spectra
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Byte-by-byte Description of file: tablec2.dat
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Bytes Format Units Label Explanations
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1- 14 F14.6 d BJD Barycentric Julian date
16- 21 F6.2 m/s RVT Barycentric Doppler measurement with HARPS-TERRA
23- 26 F4.2 m/s e_RVT Uncertainty of RVT
28- 33 F6.2 m/s RVC ?=- Doppler measurement with CCF
(cross-correlation method)
35- 38 F4.2 m/s e_RVC ?=- Uncertainty of RVC
40- 45 F6.4 km/s FWHM ?=- FWHM activity index
47- 53 F7.3 m/s BIS ?=- Line bisector (BIS) activity index
55- 60 F6.4 --- S CaII H+K S-index in the Mount Wilson system
62- 67 F6.4 --- e_S Uncertainty in S
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Acknowledgements:
Guillem Anglada-Escude, guillem.anglada(at)gmail.com
(End) Patricia Vannier [CDS] 07-Jun-2013