Artykuł w czasopiśmie
Brak miniatury
Licencja
 

Candidate Brown-dwarf Microlensing Events with Very Short Timescales and Small Angular Einstein Radii

Uproszczony widok
dc.abstract.enShort-timescale microlensing events are likely to be produced by substellar brown dwarfs (BDs), but it is difficult to securely identify BD lenses based on only event timescales ${t}_{{\rm{E}}} because short-timescale events can also be produced by stellar lenses with high relative lens-source proper motions. In this paper, we report three strong candidate BD-lens events found from the search for lensing events not only with short timescales ( ${t}_{{\rm{E}}}\lesssim 6\,\mathrm{days} ) but also with very small angular Einstein radii ( ${\theta }_{{\rm{E}}}\lesssim 0.05\,\mathrm{mas} ) among the events that have been found in the 2016-2019 observing seasons. These events include MOA-2017-BLG-147, MOA-2017-BLG-241, and MOA-2019-BLG-256, in which the first two events are produced by single lenses and the last event is produced by a binary lens. From the Monte Carlo simulations of Galactic events conducted with the combined ${t}_{{\rm{E}}} and ${\theta }_{{\rm{E}}} constraint, it is estimated that the lens masses of the individual events are ${0.051}_{-0.027}^{+0.100}\,{M}_{\odot }, ${0.044}_{-0.023}^{+0.090}\,{M}_{\odot }, and ${0.046}_{-0.023}^{+0.067}\,{M}_{\odot }/{0.038}_{-0.019}^{+0.056}\,{M}_{\odot } and the probability of the lens mass smaller than the lower limit of stars is ˜80% for all events. We point out that routine lens mass measurements of short-timescale lensing events require survey-mode space-based observations.
dc.affiliationUniwersytet Warszawski
dc.contributor.authorUdalski, Andrzej
dc.contributor.authorSzymański, Michał
dc.contributor.authorSkowron, Jan
dc.contributor.authorSoszyński, Igor
dc.contributor.authorPietrukowicz, Paweł
dc.contributor.authorKozłowski, Szymon
dc.contributor.authorHan, Cheongho
dc.contributor.authorLee, Chung-Uk
dc.contributor.authorGould, Andrew
dc.contributor.authorBond, Ian A.
dc.contributor.authorBozza, Valerio
dc.contributor.authorAlbrow, Michael D.
dc.contributor.authorChung, Sun-Ju
dc.contributor.authorHwang, Kyu-Ha
dc.contributor.authorJung, Youn Kil
dc.contributor.authorRyu, Yoon-Hyun
dc.contributor.authorShin, In-Gu
dc.contributor.authorShvartzvald, Yossi
dc.contributor.authorYee, Jennifer C.
dc.contributor.authorZang, Weicheng
dc.contributor.authorCha, Sang-Mok
dc.contributor.authorKim, Dong-Jin
dc.contributor.authorKim, Hyoun-Woo
dc.contributor.authorKim, Seung-Lee
dc.contributor.authorLee, Dong-Joo
dc.contributor.authorLee, Yongseok
dc.contributor.authorPark, Byeong-Gon
dc.contributor.authorPogge, Richard W.
dc.contributor.authorJee, M. James
dc.contributor.authorKim, Doeon
dc.contributor.authorMróz, Przemysław
dc.contributor.authorPoleski, Radosław
dc.contributor.authorUlaczyk, Krzysztof
dc.contributor.authorRybicki, Krzysztof
dc.contributor.authorIwanek, Patryk
dc.contributor.authorWrona, Marcin
dc.contributor.authorAbe, Fumio
dc.contributor.authorBarry, Richard
dc.contributor.authorBennett, David P.
dc.contributor.authorBhattacharya, Aparna
dc.contributor.authorDonachie, Martin
dc.contributor.authorFujii, Hirosane
dc.contributor.authorFukui, Akihiko
dc.contributor.authorItow, Yoshitaka
dc.contributor.authorHirao, Yuki
dc.contributor.authorKamei, Yuhei
dc.contributor.authorKondo, Iona
dc.contributor.authorKoshimoto, Naoki
dc.contributor.authorLi, Man Cheung Alex
dc.contributor.authorMatsubara, Yutaka
dc.contributor.authorMuraki, Yasushi
dc.contributor.authorMiyazaki, Shota
dc.contributor.authorNagakane, Masayuki
dc.contributor.authorRanc, Clément
dc.contributor.authorRattenbury, Nicholas J.
dc.contributor.authorSatoh, Yuki
dc.contributor.authorShoji, Hikaru
dc.contributor.authorSuematsu, Haruno
dc.contributor.authorSullivan, Denis J.
dc.contributor.authorSumi, Takahiro
dc.contributor.authorSuzuki, Daisuke
dc.contributor.authorTristram, Paul J.
dc.contributor.authorYamakawa, Takeharu
dc.contributor.authorYamawaki, Tsubasa
dc.contributor.authorYonehara, Atsunori
dc.date.accessioned2024-01-24T19:03:20Z
dc.date.available2024-01-24T19:03:20Z
dc.date.copyright2019-10-24
dc.date.issued2020
dc.description.accesstimeBEFORE_PUBLICATION
dc.description.financePublikacja bezkosztowa
dc.description.number4
dc.description.versionORIGINAL_AUTHOR
dc.description.volume159
dc.identifier.doi10.3847/1538-3881/AB6F66
dc.identifier.issn0004-6256
dc.identifier.urihttps://repozytorium.uw.edu.pl//handle/item/102663
dc.identifier.weblinkhttp://adsabs.harvard.edu/abs/2020AJ....159..134H
dc.languageeng
dc.pbn.affiliationastronomy
dc.relation.ispartofAstronomical Journal
dc.relation.pages134
dc.rightsOther
dc.sciencecloudnosend
dc.titleCandidate Brown-dwarf Microlensing Events with Very Short Timescales and Small Angular Einstein Radii
dc.typeJournalArticle
dspace.entity.typePublication