J/A+A/608/A120 GJ 1214b optical and near-IR transit phot. (Angerhausen+, 2017)
Simultaneous multicolour optical and near-IR transit photometry of GJ 1214b
with SOFIA.
Angerhausen D., Dreyer C., Placek B., Csizmadia Sz., Eigmueller P.,
Godolt M., Kitzmann D., Mallonn M., Becklin E., Collins P., Dunham E.W.,
Grenfell J.L., Hamilton R.T., Kabath P., Logsdon S.E., Mandell A.,
Mandushev G., McElwain M., McLean I.S., Pfueller E., Rauer H., Savage M.,
Shenoy S., Vacca W.D., Van Cleve J.E., Wiedemann M., Wolf J.
<Astron. Astrophys. 608, A120 (2017)>
=2017A&A...608A.120A 2017A&A...608A.120A (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Planets ; Photometry, SDSS ;
Photometry, infrared
Keywords: planets and satellites: individual: GJ 1214b -
planets and satellites: atmospheres - techniques: photometric -
methods: observational - methods: data analysis - stars: activity
Abstract:
The benchmark exoplanet GJ 1214b is one of the best studied transiting
planets in the transition zone between rocky Earth-sized planets and
gas or ice giants. This class of super-Earth or mini-Neptune planets
is unknown in our solar system, yet is one of the most frequently
detected classes of exoplanets. Understanding the transition from
rocky to gaseous planets is a crucial step in the exploration of
extrasolar planetary systems, in particular with regard to the
potential habitability of this class of planets.
GJ 1214b has already been studied in detail from various platforms at
many different wavelengths. Our airborne observations with the
Stratospheric Observatory for Infrared Astronomy (SOFIA) add
information in the Paschen-αcont. 1.9um infrared wavelength
band, which is not accessible by any other current ground- or
space-based instrument due to telluric absorption or limited spectral
coverage.
We used FLIPO, the combination of the High-speed Imaging Photometer
for Occultations (HIPO) and the First Light Infrared TEst CAMera
(FLITECAM) and the Focal Plane Imager (FPI+) on SOFIA to
comprehensively analyse the transmission signal of the possible
water-world GJ 1214b through photometric observations during transit
in three optical and one infrared channels.
We present four simultaneous light curves and corresponding transit
depths in three optical and one infrared channel, which we compare to
previous observations and current synthetic atmospheric models of
GJ 1214b. The final precision in transit depth is between 1.5 and 2.5
times the theoretical photon noise limit, not sensitive enough to
constrain the theoretical models any better than previous
observations. This is the first exoplanet observation with SOFIA that
uses its full set of instruments available to exoplanet
spectrophotometry. Therefore we use these results to evaluate SOFIAs
potential in this field and suggest future improvements.
Description:
The joint US-German Cycle 2 Guest Investigator (GI) programme -
US-proposal: Angerhausen (2013); Germanproposal: Dreyer (2013) - was
performed on SOFIAs flight number 149 on UT February 27, 2014.
Observations were simultaneously conducted in two optical HIPO
channels: open blue at 0.3-0.6um and Sloan z' at 0.9-m; and one
infrared FLITECAM fiter: Paschen-α cont. at 1.9um.
Complementary data were also obtained with the optical focal plane
guiding camera FPI+ in the Sloan i' band (0.8um).
Objects:
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RA (2000) DE Designation(s)
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17 15 18.94 +04 57 49.7 GJ 1214 = LHS 3275
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 60 4 Observation summary
hipoblue.dat 15 434 SOFIA GJ1214 HIPO blue (open blue) data
hipored.dat 15 436 SOFIA GJ1214 HIPO red (SDSS z') data
fpip.dat 15 4425 SOFIA GJ1214 HIPO FPI (SDSS i') data
flitecam.dat 15 255 SOFIA GJ1214 HIPO FLITECAM (Pa α cont.) data
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See also:
J/A+A/549/A10 : Transits of GJ 1214 (Harpsoe+, 2013)
J/A+A/563/A21 : GJ 1214 Trappist and Spitzer light curves (Gillon+, 2014)
Byte-by-byte Description of file: table2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 9 A9 --- Inst Instrument designation
11- 26 A16 --- Band Pass-band designation (1)
28- 31 F4.2 um lambdaEff Effective wavelength or lower value of
effective wavelength interval (1)
32 A1 --- --- [-]
33- 35 F3.1 um BlambdaEff ? Upper value of effective wavelength interval
37- 40 F4.2 um Width Band width
42- 47 A6 s ExpTime Exposure time
49- 60 A12 --- FileName Name of the file with photometry
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Note (1): taken from Sofia Observer's Handbook for Cycle 2: v2.1.2 .
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Byte-by-byte Description of file: hipoblue.dat hipored.dat fpip.dat flitecam.dat
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Bytes Format Units Label Explanations
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1- 7 F7.5 d HJD Heliocentric Julian date (HJD-2456715)
9- 15 F7.5 --- RFlux Relative flux
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Acknowledgements:
Daniel Angerhausen, daniel.angerhausen(at)gmail.com
(End) Patricia Vannier [CDS] 11-Dec-2017