SHIN, I.-G.
(Harvard-Smithsonian Center for Astrophysics)
,
RYU, Y.-H.
(Korea Astronomy and Space Science Institute)
,
UDALSKI, A.
(Warsaw University Observatory)
,
ALBROW, M.
(Department of Physics and Astronomy, University of Canterbury)
,
CHA, S.-M.
(Korea Astronomy and Space Science Institute)
,
CHOI, J.-Y.
(Busan National Science Museum)
,
CHUNG, S.-J.
(Korea Astronomy and Space Science Institute)
,
HAN, C.
(Department of Physics, Chungbuk National University)
,
HWANG, K.-H.
(Department of Physics, Chungbuk National University)
,
JUNG, Y.K.
(Harvard-Smithsonian Center for Astrophysics)
,
KIM, D.-J.
(Korea Astronomy and Space Science Institute)
,
KIM, S.-L.
(Korea Astronomy and Space Science Institute)
,
LEE, C.-U.
(Korea Astronomy and Space Science Institute)
,
LEE, Y.
(Korea Astronomy and Space Science Institute)
,
PARK, B.-G.
(Korea Astronomy and Space Science Institute)
,
PARK, H.
(Busan National Science Museum)
,
POGGE, R.W.
(Department of Astronomy Ohio State University)
,
YEE, J.C.
(Harvard-Smithsonian Center for Astrophysics)
,
PIETRUKOWICZ, P.
(Warsaw University Observatory)
,
MROZ, P.
(Warsaw University Observatory)
,
KOZLOWSKI, S.
(Warsaw University Observatory)
,
POLESKI, R.
(Warsaw University Observatory)
,
SKOWRON, J.
(Warsaw University Observatory)
,
SOSZYNSKI, I.
(Warsaw University)
,
SZYMANSKI, M.K.
,
ULACZYK, K.
,
WYRZYKOWSKI, L.
,
PAWLAK, M.
,
GOULD, A.
We report the characterization of a massive (mp = 3.9±1.4Mjup) microlensing planet (OGLE-2015-BLG-0954Lb) orbiting an M dwarf host (M = 0.33 ± 0.12M⊙) at a distance toward the Galactic bulge of $0.6^{+0.4}_{-0.2}kpc$, which is extremely nearby by microlensing standards. Th...
We report the characterization of a massive (mp = 3.9±1.4Mjup) microlensing planet (OGLE-2015-BLG-0954Lb) orbiting an M dwarf host (M = 0.33 ± 0.12M⊙) at a distance toward the Galactic bulge of $0.6^{+0.4}_{-0.2}kpc$, which is extremely nearby by microlensing standards. The planet-host projected separation is a⊥ ~ 1.2AU. The characterization was made possible by the wide-field (4 deg2) high cadence (Γ = 6 hr–1) monitoring of the Korea Microlensing Telescope Network (KMTNet), which had two of its three telescopes in commissioning operations at the time of the planetary anomaly. The source crossing time t* = 16 min is among the shortest ever published. The high-cadence, wide-field observations that are the hallmark of KMTNet are the only way to routinely capture such short crossings. High-cadence resolution of short caustic crossings will preferentially lead to mass and distance measurements for the lens. This is because the short crossing time typically implies a nearby lens, which enables the measurement of additional effects (bright lens and/or microlens parallax). When combined with the measured crossing time, these effects can yield planet/host masses and distance.
We report the characterization of a massive (mp = 3.9±1.4Mjup) microlensing planet (OGLE-2015-BLG-0954Lb) orbiting an M dwarf host (M = 0.33 ± 0.12M⊙) at a distance toward the Galactic bulge of $0.6^{+0.4}_{-0.2}kpc$, which is extremely nearby by microlensing standards. The planet-host projected separation is a⊥ ~ 1.2AU. The characterization was made possible by the wide-field (4 deg2) high cadence (Γ = 6 hr–1) monitoring of the Korea Microlensing Telescope Network (KMTNet), which had two of its three telescopes in commissioning operations at the time of the planetary anomaly. The source crossing time t* = 16 min is among the shortest ever published. The high-cadence, wide-field observations that are the hallmark of KMTNet are the only way to routinely capture such short crossings. High-cadence resolution of short caustic crossings will preferentially lead to mass and distance measurements for the lens. This is because the short crossing time typically implies a nearby lens, which enables the measurement of additional effects (bright lens and/or microlens parallax). When combined with the measured crossing time, these effects can yield planet/host masses and distance.
KMTNet scientific observations commenced on 10 March, 21 February, and 20 June in Chile (CTIO), South Africa (SAAO), and Australia (SSO), respectively. Overall the data from CTIO, SAAO, and SSO are of good science quality, but the commissioning observations were impacted by a variety of engineeringrelated issues ranging from breaks in the schedule to adjustment of the detector electronics. In the case of the CTIO data there are two times when the detector electronics changed substantially.
대상 데이터
The three KMTNet telescopes were all commissioned in the 2015 bulge season, taking their first scientific data in February (South Africa), March (Chile), and June (Australia). During this commissioning season, they simultaneously took scientific data and underwent various engineering tests and adjustments.
성능/효과
will be large and hence more easily measurable. Either of these effects can provide the second parameter needed for a complete solution, provided that the Einstein radius has been measured by resolving the caustic crossing.
7 mas) and to the arguments that the lens must be in the near disk (from the high proper motion µrel = 18 mas yr-1). Hence, it was crucial both to the mass estimates of the host (0.33±0.12 M⊙) and planet (3.9±1.4 Mjup), and to the recognition that the lens and source will be separately resolvable in just a few years.
No parallax effects were detected in the light curve. Hence, we could not obtain a definitive measurement. Instead we estimated the lens mass and distance based on kinematic arguments from its high proper motion.
High-cadence Γ = 6 hr -1 observations by KMTNet resolved the extremely short 2tcc = 33 minute caustic crossing of the planetary event OGLE-2015-BLG-0954. This proved crucial to both the measurement of the Einstein radius (θE = 1.
In the case of OGLE-2015-BLG-0954, we were able to constrain the mass of the lens from the limit on lens light. No parallax effects were detected in the light curve. Hence, we could not obtain a definitive measurement.
They are also consistent with a white dwarf host, although this would be more surprising. The nature of the lens can be completely resolved in a few years based on high resolution imaging.
These are consistent with independent arguments derived from upper limits on lens light. They are also consistent with a white dwarf host, although this would be more surprising. The nature of the lens can be completely resolved in a few years based on high resolution imaging.
High-cadence Γ = 6 hr -1 observations by KMTNet resolved the extremely short 2tcc = 33 minute caustic crossing of the planetary event OGLE-2015-BLG-0954. This proved crucial to both the measurement of the Einstein radius (θE = 1.7 mas) and to the arguments that the lens must be in the near disk (from the high proper motion µrel = 18 mas yr-1). Hence, it was crucial both to the mass estimates of the host (0.
will be large and hence more easily measurable. Either of these effects can provide the second parameter needed for a complete solution, provided that the Einstein radius has been measured by resolving the caustic crossing.
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