J/AJ/159/256 Light curve of OGLE-2018-BLG-0677 (Herrera-Martin+, 2020)
OGLE-2018-BLG-0677Lb: a Super-Earth near the Galactic Bulge.
Herrera-Martin A., Albrow M.D., Udalski A., Gould A., Ryu Y.-H., Yee J.C.,
Chung S.-J., Han C., Hwang K.-H., Jung Y.K., Lee C.-U., Shin I.-G.,
Shvartzvald Y., Zang W., Cha S.-M., Kim D.-J., Kim H.-W., Kim S.-L.,
Lee D.-J., Lee Y., Park B.-G., Pogge R.W., Szymanski M.K., Mroz P.,
Skowron J., Poleski R., Soszynski I., Kozlowski S., Pietrukowicz P.,
Ulaczyk K., Rybicki K., Iwanek P., Wrona M.
<Astron. J., 159, 256 (2020)>
=2020AJ....159..256H 2020AJ....159..256H
ADC_Keywords: Gravitational lensing; Exoplanets; Photometry; Optical
Keywords: Gravitational microlensing exoplanet detection ;
Gravitational microlensing ; Astrostatistics strategies ;
Super Earths ; Exoplanets
Abstract:
We report the analysis of the microlensing event OGLE-2018-BLG-0677. A
small feature in the light curve of the event leads to the discovery
that the lens is a star-planet system. Although there are two
degenerate solutions that could not be distinguished for this event,
both lead to a similar planet-host mass ratio. We perform a Bayesian
analysis based on a Galactic model to obtain the properties of the
system and find that the planet corresponds to a super-
Earth/sub-Neptune with a mass of
Mplanet=3.96-2.66+5.88M⊕. The host star has a mass of
Mhost=0.12-0.08+0.14M☉. The projected separation for the
inner and outer solutions are 0.63-0.17+0.20au and
0.72-0.19+0.23au respectively. At
Δχ2=χ2(1L1S-χ2(2L1S)=46, this is by far the
lowest Δχ2 for any securely detected microlensing planet
to date, a feature that is closely connected to the fact that it is
detected primarily via a "dip" rather than a "bump."
Description:
Observations were made with the Optical Gravitational Lensing
Experiment (OGLE; Udalski, 2003AcA....53..291) and KMTNet.
The event was first detected by the OGLE Early Warning System with
designations OGLE-2018-BLG-0677 and OGLE-2018-BLG-0680, since it lies
in the overlap region of two survey fields. The observations from the
two fields have a frequency of 1-3 data points per day.
KMTNet is a wide-field imaging system, with three telescopes and
cameras sharing the same specifications, installed at Cerro-Tololo
Inter-American Observatory in Chile (KMTC), the South African
Astronomical Observatory in South Africa (KMTS), and the Siding Spring
Observatory in Australia (KMTA). The telescopes each have a 1.6m
primary mirror, and a wide-field camera (a mosaic of four 9kx9kCCDs)
that image approximately a 2.0x2.0 square degree field of view.
Objects:
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RA (2000) DE Designation(s)
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17 55 00.270 -32 00 59.51 OGLE-2018-BLG-0677 = KMT-2018-BLG-0816
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fig1.dat 45 1624 Light curve for OGLE-2018-BLG-0677
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See also:
J/AcA/50/1 : OGLE microlensing events in Galactic Bulge (Udalski+, 2000)
J/AcA/50/307 : OGLE LMC BVI photometry (Udalski+, 2000)
J/AcA/52/217 : OGLE II. VI photometry of Galactic Bulge (Udalski+, 2002)
J/ApJ/631/906 : MACHO Galactic Bulge microlensing events (Thomas+, 2005)
J/ApJ/636/240 : OGLE II microlensing parameters (Sumi+, 2006)
J/ApJ/668/643 : Multiply imaged gravitational lens systems (Limousin+, 2007)
J/ApJ/711/L48 : 2008 OGLE Bulge microlensing alerts (Cohen+, 2010)
J/A+A/533/A134 : Abundances of microlensed stars in the Bulge (Bensby+, 2011)
J/ApJ/755/31 : Compilation of 122 strong gravitational lenses (Cao+, 2012)
J/ApJS/216/12 : OGLE-III Galactic bulge microlensing (Wyrzykowski+, 2015)
J/A+A/617/A135 : 20 years of photometric microlensing (Mustill+, 2018)
J/ApJS/244/29 : Microlensing events toward the Galactic bulge (Mroz+, 2019)
Byte-by-byte Description of file: fig1.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Inst Instrument identifier (1)
15- 23 F9.4 d HJD [8200/8260] Heliocentric Julian Date; HJD-2450000
25- 35 F11.6 --- Flux [97.3/1836] Relative flux
37- 45 F9.6 --- e_Flux [8.1/75] Uncertainty in Flux
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Note (1): Instruments as follows:
KMTA01 = Siding Spring Observatory in Australia, BLG01
KMTA41 = Siding Spring Observatory in Australia, BLG41
KMTC01 = Cerro-Tololo Inter-American Observatory in Chile, BLG01
KMTC41 = Cerro-Tololo Inter-American Observatory in Chile, BLG41
KMTS01 = South African Astronomical Observatory in South Africa,
BLG01
KMTS41 = South African Astronomical Observatory in South Africa,
BLG41
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 07-Jul-2020