J/AJ/158/251 New reduction of UVES data for 35 M dwarfs (Butler+, 2019)
A reanalysis of the UVES M Dwarf Planet Search program.
Butler R.P., Jones H.R.A., Feng F., Tuomi M., Anglada-Escude G., Keiser S.
<Astron. J., 158, 251 (2019)>
=2019AJ....158..251B 2019AJ....158..251B (SIMBAD/NED BibCode)
ADC_Keywords: Stars, dwarfs ; Stars, M-type ; Radial velocities ; Exoplanets
Keywords: Radial velocity - Exoplanets
Abstract:
The UVES (Ultraviolet and Visible Spectrometer) M Dwarf Planet Search
program surveyed 40 M dwarfs and 1 M giant from 2000 through 2007 March.
Two of the M dwarfs were double-lined spectroscopic binaries. The 38
single-lined M dwarfs in this survey are among the nearest and brightest
M dwarfs. Starting with the reduced 1D spectra provided by the UVES team,
we reanalyzed the UVES velocities of Proxima Cen as part of the
"Pale Red Dot" program. The velocity rms decreased from 3.6 to 2.3 m/s.
Motivated by this result, we have harvested all of the raw data from the
UVES M Dwarf Planet Search from the European Southern Observatory (ESO)
archives and have written custom packages to generate 1D spectra from
the raw data, and velocities from the 1D spectra. The median improvement
in the velocity rms from the new analysis is 1.8 m/s. Six of the 38
M dwarfs from the original study had a velocity rms<4 m/s. In the
reanalysis presented here, 22 of these stars have a velocity rms<4 m/s.
We improve the upper limits on possible planets orbiting these stars
by a factor of typically two to three. For many of these M dwarfs, these
observations represent the first epoch of high-precision velocity
measurements.
Description:
UVES is a dual-arm cross dispersed echelle spectrometer. UVES is not
thermally stabilized. At an elevation of 2635 m it is not subject to
extreme temperature variations. For precision velocity measurements,
an Iodine absorption cell is mounted directly in front of the spectrometer
entrance (Marcy & Butler 1992PASP..104..270M 1992PASP..104..270M), superimposing a dense
forest of Iodine lines from 5000 to 6200 Å, which serve as a wavelength
standard. The blue arm of the UVES spectrometer covers the Iodine region.
For precision velocity measurements either the 0.3" slit (Butler et al.
2004ApJ...600L..75B 2004ApJ...600L..75B; Kjeldsen et al. 2005ApJ...635.1281K 2005ApJ...635.1281K), or the fiber
slicer (image slicer #3) yielding an effective 0.3" slit
(Zechmeister et al. 2009, J/A+A/505/859), is used. The most important
attribute of a precision velocity spectrometer is resolution. The
resolution of UVES in either mode is 130 K, higher than most of the
existing precision velocity spectrometers.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 58 39 UVES M Dwarf Planet Search
table2.dat 37 1695 New reduction of UVES data for 35 M dwarfs
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See also:
J/A+A/505/859 : M dwarfs radial velocities (Zechmeister+, 2009)
J/A+A/541/A9 : M dwarfs activity and radial velocity (Gomes da Silva+, 2012)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Star Stellar identifier
10 A1 --- n_Star [a] Note on Star (1)
12- 19 A8 --- ZName Name assigned by Zechmeister et al. (2009,
J/A+A/505/859)
21- 27 A7 --- SpType Spectral type
29- 33 F5.2 mag Vmag [8.14/12.5] V band magnitude
35- 36 I2 --- Nobs [5/76] Number of observations
38- 43 F6.1 m/s Urms [2.5/3486] Velocity rms from Zechmeister et al.
(2009, J/A+A/505/859)
45- 51 F7.2 m/s Vrms [1.63/3487.7] Velocity rms from our analysis
53- 58 F6.2 m/s Qdiff [1.34/668] Quadrature difference of the previous
two columns
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Note (1): Note as follows:
a = Keplerian fit: p=168.8 days, K=1828, e=0.28, Msini=32 Mjup, rms=1.77 m/s.
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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- 9 A9 --- Star Stellar identifier
11- 23 F13.5 d BJD Barycentric Julian Date
25- 32 F8.2 m/s RV [-7324.41/1329.07] Radial velocity
34- 37 F4.2 m/s e_RV [0.6/7.66] Uncertainty in RV
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History:
From electronic version of the journal
(End) Prepared by [AAS], Tiphaine Pouvreau [CDS] 05-Feb-2020