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Title: On the Possibility of Stellar Lenses in the Black Hole Candidate Microlensing Events MACHO-96-BLG-5 and MACHO-98-BLG-6
Award ID(s):
1909641
PAR ID:
10250640
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
912
Issue:
2
ISSN:
0004-637X
Page Range / eLocation ID:
146
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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    Aims. We investigate the 2023 season data from high-cadence microlensing surveys with the aim of detecting partially covered shortterm signals and revealing their underlying astrophysical origins. Through this analysis, we ascertain that the signals observed in the lensing events KMT-2023-BLG-0416, KMT-2023-BLG-1454, and KMT-2023-BLG-1642 are of planetary origin. Methods. Considering the potential degeneracy caused by the partial coverage of signals, we thoroughly investigate the lensing-parameter plane. In the case of KMT-2023-BLG-0416, we have identified two solution sets, one with a planet-to-host mass ratio ofq~ 10−2and the other withq~ 6 × 10−5, within each of which there are two local solutions emerging due to the inner-outer degeneracy. For KMT-2023-BLG-1454, we discern four local solutions featuring mass ratios ofq~ (1.7−4.3) × 10−3. When it comes to KMT-2023-BLG-1642, we identified two locals withq~ (6 − 10) × 10−3resulting from the inner-outer degeneracy. Results. We estimate the physical lens parameters by conducting Bayesian analyses based on the event time scale and Einstein radius. For KMT-2023-BLG-0416L, the host mass is ~0.6M⊙, and the planet mass is ~(6.1−6.7)MJaccording to one set of solutions and ~0.04MJaccording to the other set of solutions. KMT-2023-BLG-1454Lb has a mass roughly half that of Jupiter, while KMT-2023-BLG-1646Lb has a mass in the range of between 1.1 to 1.3 times that of Jupiter, classifying them both as giant planets orbiting mid M-dwarf host stars with masses ranging from 0.13 to 0.17 solar masses. 
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  2. ; ; ; ; ; ; ; ; ; ; et al (, Astronomy & Astrophysics)
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  3. ; ; ; ; ; ; ; ; ; ; et al (, Astronomy & Astrophysics)
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