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Title: Detections of Planets in Binaries Through the Channel of Chang–Refsdal Gravitational Lensing Events

Abstract

Chang–Refsdal (C–R) lensing, which refers to the gravitational lensing of a point mass perturbed by a constant external shear, provides a good approximation in describing lensing behaviors of either a very wide or a very close binary lens. C–R lensing events, which are identified by short-term anomalies near the peak of high-magnification lensing light curves, are routinely detected from lensing surveys, but not much attention is paid to them. In this paper, we point out that C–R lensing events provide an important channel to detect planets in binaries, both in close and wide binary systems. Detecting planets through the C–R lensing event channel is possible because the planet-induced perturbation occurs in the same region of the C–R lensing-induced anomaly and thus the existence of the planet can be identified by the additional deviation in the central perturbation. By presenting the analysis of the actually observed C–R lensing event OGLE-2015-BLG-1319, we demonstrate that dense and high-precision coverage of a C–R lensing-induced perturbation can provide a strong constraint on the existence of a planet in a wide range of planet parameters. The sample of an increased number of microlensing planets in binary systems will provide important observational constraints in giving shape tomore » the details of planet formation, which have been restricted to the case of single stars to date.« less

Authors:
 [1]; ;  [2]
  1. Department of Physics, Chungbuk National University, Cheongju 361-763 (Korea, Republic of)
  2. Harvard-Smithsonian Center for Astrophysics, 60 Garden St., Cambridge, MA 02138 (United States)
Publication Date:
OSTI Identifier:
22663850
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 835; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCURACY; APPROXIMATIONS; BINARY STARS; DETECTION; DISTURBANCES; GRAVITATIONAL LENSES; LIMITING VALUES; MASS; PERTURBATION THEORY; PLANETS; STARS; VISIBLE RADIATION

Citation Formats

Han, Cheongho, Shin, In-Gu, and Jung, Youn Kil. Detections of Planets in Binaries Through the Channel of Chang–Refsdal Gravitational Lensing Events. United States: N. p., 2017. Web. doi:10.3847/1538-4357/835/2/115.
Han, Cheongho, Shin, In-Gu, & Jung, Youn Kil. Detections of Planets in Binaries Through the Channel of Chang–Refsdal Gravitational Lensing Events. United States. doi:10.3847/1538-4357/835/2/115.
Han, Cheongho, Shin, In-Gu, and Jung, Youn Kil. Wed . "Detections of Planets in Binaries Through the Channel of Chang–Refsdal Gravitational Lensing Events". United States. doi:10.3847/1538-4357/835/2/115.
@article{osti_22663850,
title = {Detections of Planets in Binaries Through the Channel of Chang–Refsdal Gravitational Lensing Events},
author = {Han, Cheongho and Shin, In-Gu and Jung, Youn Kil},
abstractNote = {Chang–Refsdal (C–R) lensing, which refers to the gravitational lensing of a point mass perturbed by a constant external shear, provides a good approximation in describing lensing behaviors of either a very wide or a very close binary lens. C–R lensing events, which are identified by short-term anomalies near the peak of high-magnification lensing light curves, are routinely detected from lensing surveys, but not much attention is paid to them. In this paper, we point out that C–R lensing events provide an important channel to detect planets in binaries, both in close and wide binary systems. Detecting planets through the C–R lensing event channel is possible because the planet-induced perturbation occurs in the same region of the C–R lensing-induced anomaly and thus the existence of the planet can be identified by the additional deviation in the central perturbation. By presenting the analysis of the actually observed C–R lensing event OGLE-2015-BLG-1319, we demonstrate that dense and high-precision coverage of a C–R lensing-induced perturbation can provide a strong constraint on the existence of a planet in a wide range of planet parameters. The sample of an increased number of microlensing planets in binary systems will provide important observational constraints in giving shape to the details of planet formation, which have been restricted to the case of single stars to date.},
doi = {10.3847/1538-4357/835/2/115},
journal = {Astrophysical Journal},
number = 2,
volume = 835,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}
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