J/AJ/161/283 Radial velocity estimates of 4 stars with IGRINS (Stahl+, 2021)
IGRINS RV: A Precision Radial Velocity Pipeline for IGRINS Using Modified
Forward Modeling in the Near-infrared.
Stahl A.G., Tang S.-Y., Johns-Krull C.M., Prato L., Llama J., Mace G.N.,
Joon Lee J., Oh H., Luna J., Jaffe D.T.
<Astron. J., 161, 283 (2021)>
=2021AJ....161..283S 2021AJ....161..283S
ADC_Keywords: Exoplanets; Stars, standard; Spectra, infrared; Radial velocities;
Spectral types; Effective temperatures
Keywords: Exoplanet detection methods ; Exoplanet formation ; Radial velocity ;
Near infrared astronomy ; Open source software ; Astronomy software ;
Starspots ; Young stellar objects
Abstract:
Application of the radial velocity (RV) technique in the near-infrared
is valuable because of the diminished impact of stellar activity at
longer wavelengths, making it particularly advantageous for the study
of late-type stars but also for solar-type objects. In this paper, we
present the IGRINS RV open-source python pipeline for computing
infrared RV measurements from reduced spectra taken with IGRINS, an
R~λ/Δλ∼45000 spectrograph with simultaneous
coverage of the H-band (1.49-1.80µm) and K-band (1.96-2.46µm).
Using a modified forward-modeling technique, we construct
high-resolution telluric templates from A0 standard observations on a
nightly basis to provide a source of common-path wavelength
calibration while mitigating the need to mask or correct for telluric
absorption. Telluric standard observations are also used to model the
variations in instrumental resolution across the detector, including a
yearlong period when the K-band was defocused. Without any additional
instrument hardware, such as a gas cell or laser frequency comb, we
are able to achieve precisions of 26.8m/s in the K-band and 31.1m/s in
the H-band for narrow-line hosts. These precisions are empirically
determined by a monitoring campaign of two RV standard stars, as well
as the successful retrieval of planet-induced RV signals for both
HD189733 and τBooA; furthermore, our results affirm the presence
of the Rossiter-McLaughlin effect for HD189733. The IGRINS RV pipeline
extends another important science capability to IGRINS, with publicly
available software designed for widespread use.
Description:
The Immersion Grating INfrared Spectrometer (IGRINS) is a
high-resolution (R∼45000) cross-dispersed echelle spectrograph with a
broad spectral grasp covering the full H-band (1.49-1.80µm) and
K-band (1.96-2.46µm) simultaneously. The former is split into 28
orders, and the latter is split into 26 orders, where each order
corresponds to ∼240Å and consists of 2048 pixels.
IGRINS saw first light on McDonald Observatory's 2.7m Harlan J.Smith
Telescope in 2014. It was then moved to the Lowell Discovery Telescope
(LDT) in 2016 August. Currently, IGRINS is available as a visiting
instrument at the Gemini South Telescope. In this paper, we only use
data taken while IGRINS was mounted at McDonald Observatory (McD) and
at Lowell Observatory.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 96 4 Test target basic information
table4.dat 37 703 Radial velocity estimates
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See also:
I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/AJ/121/2148 : Precise spectral types for 372 A, F & G stars (Gray+, 2001)
J/AJ/126/2048 : NStars project: the Northern Sample. I. (Gray+, 2003)
J/ApJ/622/1102 : The planet-metallicity correlation. (Fischer+, 2005)
J/ApJ/646/505 : Catalog of nearby exoplanets (Butler+, 2006)
J/A+A/521/A12 : Radial velocities of nearby late-type stars (Maldonado+, 2010)
J/AJ/145/102 : Spectroscopy of bright Mdwarfs in northern sky (Lepine+, 2013)
J/ApJS/210/20 : Small Kepler planets radial velocities (Marcy+, 2014)
J/A+A/578/A64 : Velocity curve of τ Boo A (Borsa+, 2015)
J/ApJS/225/32 : Extended abundance analysis of cool stars (Brewer+, 2016)
J/AJ/152/75 : Photometric survey IC2391, η Cha, & USco (Oelkers+, 2016)
J/AJ/153/208 : LCES HIRES/Keck RVel Exoplanet Survey (Butler+, 2017)
J/ApJ/838/152 : Deep NIR spectrum of the Orion Bar PDR (Kaplan+, 2017)
J/A+A/616/A7 : Gaia DR2 RVel standard stars catalog (Soubiran+, 2018)
J/AJ/157/113 : TESS M-dwarf exoplanetary systems (Ballard, 2019)
J/A+A/629/A80 : ESPRESSO blind RV exoplanet survey catalog (Hojjatpanah+,2019)
J/A+A/625/A59 : tau Boo Radial velocities & astrometric data (Justesen+, 2019)
J/A+A/624/A68 : 47 single-line eclipsing bin. BEBOP velocities (Martin+, 2019)
J/A+A/623/A44 : CARMENES M-dwarfs activity indicators (Schoefer+, 2019)
J/A+A/625/A68 : Radii and masses of the CARMENES targets (Schweitzer+, 2019)
J/ApJ/877/12 : Coma Ber & a Neighbor Stellar Group tidal tails (Tang+, 2019)
J/AJ/159/60 : 8695 flares from 1228 stars, TESS sectors 1&2 (Gunther+, 2020)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Target name
11- 12 I2 h RAh [4/20] Hour of right ascension (J2000)
14- 15 I2 min RAm Minute of right ascension (J2000)
17- 21 F5.2 s RAs Second of right ascension (J2000)
23 A1 --- DE- [+] Sign of declination (J2000)
25- 26 I2 deg DEd [0/22] Degree of declination (J2000)
28- 29 I2 arcmin DEm Arcminute of declination (J2000)
31- 34 F4.1 arcsec DEs Arcsecond of declination (J2000)
36- 41 A6 --- SpT Spectral type
43 A1 --- r_SpT Reference flag on SpT (1)
45- 48 I4 K Teff [4014/6387] Effective temperature
50 A1 --- r_Teff Reference flag on Teff (1)
52- 55 F4.2 [-] logg [4.27/4.66] Surface gravity
57 A1 --- r_logg Reference flag on logg (1)
59- 62 F4.2 mag Hmag [3.55/6.44] H magnitude from 2MASS (VII/233)
64- 67 F4.2 mag Kmag [3.36/6.42] K magnitude from 2MASS (VII/233)
69- 73 F5.2 pc Dist [15/56.1] Distance from Bailer-Jones+, 2018, I/347
75- 85 A11 --- Note Additional note
87- 91 F5.2 km/s RVel [20/34]? Radial velocity from this study
93- 96 F4.2 km/s vsini [2.9/9.3]? Rotational velocity from this study
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Note (1): References as follows:
a = Lepine+, 2013, J/AJ/145/102
b = Houk+, 1999mctd.book.....H 1999mctd.book.....H
c = Gray+, 2003, J/AJ/126/2048
d = Gray+, 2001, J/AJ/121/2148
e = Schweitzer+, 2019, J/A+A/625/A68
f = Brewer+, 2016, J/ApJS/225/32
g = Fischer+, 2005, J/ApJ/622/1102
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 9 A9 --- Name Target name
11 A1 --- Filt Filter used
13- 23 F11.6 d JD [6984/8560] Julian Date of observation; JD-2450000
25- 31 F7.2 m/s RVel [-632/599] Barycenter-corrected radial velocity
33- 37 F5.2 m/s e_RVel [21.6/94] Uncertainty in RVel
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 10-Sep-2021