J/AJ/159/261 LC of microlensing event OGLE-2012-BLG-0838 (Poleski+, 2020)
A Wide-orbit Exoplanet OGLE-2012-BLG-0838Lb.
Poleski R., Suzuki D., Udalski A., Xie X., Yee J.C., Koshimoto N.,
Gaudi B.S., Gould A., Skowron J., Szymanski M.K., Soszynski I.,
Pietrukowicz P., Kozlowski S., Wyrzykowski L., Ulaczyk K., Abe F.,
Barry R.K., Bennett D.P., Bhattacharya A., Bond I.A., Donachie M.,
Fujii H., Fukui A., Itow Y., Hirao Y., Kamei Y., Kondo I., Alex Li M.C.,
Matsubara Y., Miyazaki S., Muraki Y., Nagakane M., Ranc C.,
Rattenbury N.J., Satoh Y.K., Shoji H., Suematsu H., Sullivan D.J.,
Sumi T., Tristram P.J., Yamakawa T., Yamawaki T., Yonehara A., Han C.,
Dong S., Morzinski K.M., Males J.R., Close L.M., Pogge R.W.,
Beaulieu J.-P., Marquette J.-B.
<Astron. J., 159, 261 (2020)>
=2020AJ....159..261P 2020AJ....159..261P
ADC_Keywords: Exoplanets; Gravitational lensing; Photometry, VRI
Keywords: Gravitational microlensing ; Exoplanet detection methods ;
Extrasolar ice giants
Abstract:
We present the discovery of a planet on a very wide orbit in the
microlensing event OGLE-2012-BLG-0838. The signal of the planet is
well separated from the main peak of the event and the planet-star
projected separation is found to be twice the Einstein ring radius,
which corresponds to a projected separation of ∼4au. Similar planets
around low-mass stars are very hard to find using any technique other
than microlensing. We discuss microlensing model fitting in detail and
discuss the prospects for measuring the mass and distance of the lens
system directly.
Description:
Optical Gravitational Lensing Experiment (OGLE) is a large-scale
photometric survey. It is currently in its fourth phase (OGLE-IV) and
operates a 1.3m telescope at Las Campanas Observatory (Chile) that is
equipped with a 32CCD chip camera (256Mpixels in total). The camera
field of view is 1.4deg2, and the pixel scale is 0.26". OGLE bulge
observations are performed in the I-band, and we use only these to fit
the microlensing model.
The Microlensing Observations in Astrophysics (MOA) collaboration also
conducts a microlensing survey toward the bulge using the MOA-II 1.8m
telescope. The telescope is located at Mt. John University Observatory
(New Zealand). The camera used is the MOA-cam3. It is mounted on the
prime focus of the telescope and has field of view of 2.2deg2, which
enables high-cadence observations.
The Variables in the Via Lactea (VVV) survey observed the Galactic
bulge between 2010 and 2015 using the near-infrared 4m Visible and
Infrared Survey Telescope for Astronomy (VISTA) telescope situated at
the Paranal Observatory (Chile). VVV took most of its observations in
the Ks band.
The Microlensing Follow Up Network ({micro}FUN) initiated observations
using the ANDICAM dual-beam optical-infrared camera on the Small and
Medium Research Telescope System (SMARTS) 1.3m telescope at Cerro
Tololo InterAmerican Observatory (CTIO, Chile). The sole purpose of
these observations was to characterize the source, primarily to
measure the H-band source flux in order to compare to possible future
high-resolution adaptive optics imaging. During these H-band
observations using the infrared channel, the optical channel was used
to obtain V and I data as a backup for the unlikely possibility of
problems with the OGLE V-band data.
Objects:
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RA (2000) DE Designation(s)
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18 12 00.74 -25 42 41.8 OGLE-2012-BLG-0838 = EWS 2012-BLG-838
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
figure1.dat 66 1177 Light curve of OGLE-2012-BLG-0838
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See also:
II/337 : VISTA Variables in the Via Lactea Survey DR1 (Saito+, 2012)
I/345 : Gaia DR2 (Gaia Collaboration, 2018)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/AcA/50/421 : OGLE-II DIA BUL_SC1 field (Wozniak, 2000)
J/A+A/428/587 : Cepheids BVRIJHK dereddened magnitudes (Kervella+, 2004)
J/A+A/533/A134 : Abundances microlensed stars in the Bulge (Bensby+, 2011)
J/A+A/529/A75 : Limb-darkening coefficients (Claret+, 2011)
J/other/Nat/481.167 : 2002-2007 PLANET microlensing events (Assan+, 2012)
J/ApJ/814/92 : Spitzer IRAC events obs. in crowded fields (Calchi+,2015)
J/MNRAS/449/2618 : M-dwarfs Multiples (MinMs) survey. I. (Ward-Duong+,2015)
J/ApJS/224/12 : Kepler planetary candidates.VII 48-month (Coughlin+,2016)
J/A+A/595/A77 : GJ676A radial velocity curve (Sahlmann+, 2016)
J/AcA/68/183 : Predicted Microlensing Events 21st Century (Bramich+, 2018)
J/AJ/158/187 : Confirmed members nearby young moving groups (Baron+,2019)
J/AJ/158/181 : Radial velocities & S-index values for HR 5183 (Blunt+,2019)
J/AJ/158/13 : The first 300 stars observed by the GPIES (Nielsen+, 2019)
J/ApJS/244/29 : Microlensing events toward the Galactic bulge (Mroz+, 2019)
Byte-by-byte Description of file: figure1.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Inst The instrument-Filter identifier (1)
10- 22 F13.5 d HJD [2455267/2457275] Heliocentric Julian Date
24- 30 F7.1 --- Flux [3598/52581]? Observed flux
32- 36 F5.1 --- e_Flux [98/414]? Uncertainty in Flux/Mag (2)
38- 44 F7.4 mag magobs [14.1/19.5]? Observed magnitude
46- 51 F6.4 mag e_magobs [0.009/0.21]? Error on magobs (2)
53- 59 F7.4 mag mag [15.9/17.8] Brightness scaled to OGLE I-band (3)
61- 66 F6.4 mag e_mag [0.005/0.23] Uncertainty in mag
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Note (1): Instruments as follows:
MOA-Red = MOA-II 1.8mtelescope at Mt. John University Observatory
(New Zealand) in red band (349 occurrences)
MOA-V = MOA-II 1.8mtelescope at Mt. John University Observatory
(New Zealand) in V band (19 occurrences)
OGLE-I = Optical Gravitational Lensing Experiment 1.3m telescope at
Las Campanas Observatory (Chile) phase I (323 occurrences)
OGLE-V = Optical Gravitational Lensing Experiment 1.3m telescope at
Las Campanas Observatory (Chile) phase V (32 occurrences)
SMARTS-H = Small and Medium Research Telescope System 1.3m telescope at
Cerro Tololo InterAmerican Observatory (CTIO, Chile)
(150 occurrences)
VVV-Ks = Visible and Infrared Survey Telescope for Astronomy telescope a the
Paranal Observatory (Chile) in Ks band.(304 occurrences)
Note (2): After normalization.
Note (3): For convience the OGLE I band data from the Flux/Mag column
is repeated here.
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 21-Jul-2020