J/AJ/153/84 Low-resolution near-infrared stellar spectra from CIBER (Kim+, 2017)
Low-resolution near-infrared stellar spectra observed by the Cosmic Infrared
Background Experiment (CIBER).
Kim M.G., Lee H.M., Arai T., Bock J., Cooray A., Jeong W.-S., Kim S.J.,
Korngut P., Lanz A., Lee D.H., Lee M.G., Matsumoto T., Matsuura S.,
Nam U.W., Onishi Y., Shirahata M., Smidt J., Tsumura K., Yamamura I.,
Zemcov M.
<Astron. J., 153, 84-84 (2017)>
=2017AJ....153...84K 2017AJ....153...84K (SIMBAD/NED BibCode)
ADC_Keywords: Spectra, infrared ; Stars, bright ; Spectral types ;
Spectroscopy
Keywords: catalogs - infrared: stars - stars: general -
techniques: spectroscopic
Abstract:
We present near-infrared (0.8-1.8µm) spectra of 105 bright
(mJ<10) stars observed with the low-resolution spectrometer on the
rocket-borne Cosmic Infrared Background Experiment. As our
observations are performed above the Earth's atmosphere, our spectra
are free from telluric contamination, which makes them a unique
resource for near-infrared spectral calibration. Two-Micron All-Sky
Survey photometry information is used to identify cross-matched stars
after reduction and extraction of the spectra. We identify the
spectral types of the observed stars by comparing them with spectral
templates from the Infrared Telescope Facility library. All the
observed spectra are consistent with late F to M stellar spectral
types, and we identify various infrared absorption lines.
Description:
We present flux-calibrated near-infrared spectra of 105 stars from
0.8≤λ≤1.8µm with spectral resolution
15≤λ/Δλ≤30 over the range.
The Low-Resolution Spectrometer (LRS) is one of the four optical
instruments of the Cosmic Infrared Background Experiment (CIBER)
payload; the others are a narrowband spectrometer and two wide-field
imagers. The LRS is a prism-dispersed spectrometer with five
rectangular 5.35°*2.8' slits imaging a 5.8°*5.8° field of
view. The detector has 256*256 pixels at a pixel scale of 1.36'*1.36'.
CIBER has flown four times (2009 February, 2010 July, 2012 March, and
2013 June) with apogees and total exposure times of over 325km and
∼240s, respectively, in the first three flights and of 550km and 335s
in the final, non-recovered flight. Due to spurious signal
contamination from thermal emission from the shock-heated rocket skin,
we do not use the first flight data in this work.
The star spectral types are determined by fitting known spectral
templates to the measured LRS spectra. We use the Infrared Telescope
Facility (IRTF) and Pickles 1998 (Cat. J/PASP/110/863) templates for
the SED fitting. The SpeX instrument installed on the IRTF observed
stars using a medium-resolution spectrograph (R=2000). The template
library contains spectra for 210 cool stars (F to M type) with
wavelength coverage from 0.8 to 2.5µm (Cushing 2005ApJ...623.1115C 2005ApJ...623.1115C;
Rayner 2009ApJS..185..289R 2009ApJS..185..289R). The Pickles library is a synthetic
spectral library that combines spectral data from various observations
to achieve wavelength coverage from the UV (0.115µm) to the
near-infrared (2.5µm). It contains 131 spectral templates for all
star types (i.e., O to M type) with a uniform sampling interval of
5Å.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 36 11 *Rocket-commanded coordinates for the observed field
table2.dat 29 3 Number of stars rejected at each criterion
table3.dat 141 110 Star catalog
spectra/* . 110 Low-Resolution Spectrometer (LRS) spectra
hrspex/* . 110 High-resolution SpeX spectra
lrspex/* . 110 Low-resolution SpeX spectra
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Note on table1.dat: Arabic numbers after the Hyphen for the Elat fields indicate
the flight number.
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See also:
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
J/PASP/110/863 : A Stellar Spectral Flux Library: 1150 - 25000 A (Pickles 1998)
http://astro.snu.ac.kr/~mgkim/project/ciber/index.html : CIBER
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Field Field name
9 I1 --- Flight ? Flight number
11- 12 I2 h RAh Hour of Right Ascension (J2000)
14- 15 I2 min RAm Minute of Right Ascension (J2000)
17- 22 F6.3 s RAs [0/60] Second of Right Ascension (J2000)
24 A1 --- DE- Sign of the Declination (J2000)
25- 26 I2 deg DEd Degree of Declination (J2000)
28- 29 I2 arcmin DEm Arcminute of Declination (J2000)
31- 36 F6.3 arcsec DEs Arcsecond of Declination (J2000)
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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- 3 A3 --- Flight Flight
5- 10 A6 --- --- [flight]
12- 14 I3 --- Nc Total number of candidates
16- 17 I2 --- i Number of candidate stars rejected at
criterion (i) (1)
19- 20 I2 --- ii Number of candidate stars rejected at
criterion (ii) (2)
22 I1 --- iii Number of candidate stars rejected at
criterion (iii) (3)
24- 26 I3 --- iv Number of candidate stars rejected at
criterion (iv) (4)
28- 29 I2 --- Ns Total number of stars in final catalog
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Note (1): Each candidate must have J<11.
Note (2): The J-band magnitude difference between the Low-Resolution
Spectrometer (LRS) candidate and the matched 2MASS counterpart must be
<1.5.
Note (3): The J-H color difference between the Low-Resolution Spectrometer (LRS)
candidate star and the matched 2MASS counterpart must be <0.3.
Note (4): Among the candidate 2MASS counterparts within the 500'' (=6 pixel)
radius of a given Low-Resolution Spectrometer (LRS) star, the
second-brightest 2MASS star must be fainter than the brightest one by more
than 2mag at the J-band.
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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- 3 A3 --- Flight Flight (either 2nd, 3rd, or 4th)
5- 11 A7 --- Field Field name
13- 18 A6 --- Star Star identifier
20 A1 --- f_Star [e] Flag 'e' for a star observed from two
independent flights
22- 35 A14 --- Name Star name
37- 38 I2 h RAh Hour of Right Ascension (J2000) (1)
40- 41 I2 min RAm Minute of Right Ascension (J2000) (1)
43- 48 F6.3 s RAs Second of Right Ascension (J2000) (1)
50 A1 --- DE- Sign of the Declination (J2000) (1)
51- 52 I2 deg DEd Degree of Declination (J2000) (1)
54- 55 I2 arcmin DEm Arcminute of Declination (J2000) (1)
57- 62 F6.3 arcsec DEs Arcsecond of Declination (J2000) (1)
64- 69 F6.3 mag Jmag1 [6.5/11] Low-Resolution Spectrometer (LRS)
Vega J-band magnitude (2)
71- 76 F6.3 mag Hmag1 [5.7/10.7] Low-Resolution Spectrometer (LRS)
Vega H-band magnitude (2)
78- 83 F6.3 mag Jmag2 [5.7/10.6] 2MASS Vega J-band magnitude (3)
85- 90 F6.3 mag Hmag2 [5/10.1] 2MASS Vega H-band magnitude (3)
92- 96 A5 --- SpT1 SIMBAD spectral type
98-114 A17 --- SpT2 Best-fit Infrared Telescope Facility (IRTF)
spectral type (4)
116-120 F5.3 --- chi2 [0.03/4.6] Χ2
122-141 A20 --- Note Note
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Note (1): The J2000.0 right ascension and declination of a star in a sexagesimal
from 2MASS data.
Note (2): From the spectra, we can compute synthetic magnitudes in the J- and
H-bands, which facilitate comparison to Two-Micron All-Sky Survey (2MASS;
see Cutri et al. 2003, Cat. II/246) measurements. We first convert surface
brightness in nW/m2/sr to flux in nW/m2/Hz and then integrate the
monochromatic intensity over the 2MASS band, applying the filter
transmissivity of the J- and H-bands (Cohen et al. 2003AJ....126.1090C 2003AJ....126.1090C). To
determine the appropriate zero magnitude, we integrate the J- and H-band
intensity of Vega's spectrum (Bohlin & Gilliland 2004AJ....127.3508B 2004AJ....127.3508B) with
the same filter response. The J- and H-band magnitudes of each source are
then calculated.
Note (3): Vega magnitude of the matched 2MASS point source catalog (Cutri et al.
2003, Cat. II/246).
Note (4): The star spectral types are determined by fitting known spectral
templates to the measured LRS spectra. We use the Infrared Telescope
Facility (IRTF) and Pickles 1998 (Cat. J/PASP/110/863) templates for the
SED fitting. See Section 4.1 in the paper for further details.
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Byte-by-byte Description of file: spectra/*,lrspex/*
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Bytes Format Units Label Explanations
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9- 20 F12.10 um lambda Wavelength λ
29- 40 F12.10 --- Flux J-band-normalized observed Low-Resolution
Spectrometer (LRS) flux (1)
48- 60 F13.10 --- b_Flux Lower value of the flux interval
69- 80 F12.10 --- B_Flux Upper value of the flux interval
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Note (1): λfλ/λfλ(J-band).
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Byte-by-byte Description of file: hrspex/*
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Bytes Format Units Label Explanations
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9- 20 F12.10 um lambda Wavelength λ
29- 40 F12.10 --- Flux Flux
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History:
From electronic version of the journal
(End) Sylvain Guehenneux [CDS] 23-Jun-2017