OGLE-2017-BLG-0173Lb: Low-mass-ratio Planet in a "Hollywood" Microlensing Event
We present microlensing planet OGLE-2017-BLG-0173Lb, with planet-host mass ratio of either or , the lowest or among the lowest ever detected. The planetary perturbation is strongly detected, Δχ2 ∼ 10000, because it arises from a bright (therefore, large) source passing over and enveloping the planet...
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| creator | Hwang, K.-H. Udalski, A. Shvartzvald, Y. Ryu, Y.-H. Albrow, M. D. Chung, S.-J. Gould, A. Han, C. Jung, Y. K. Shin, I.-G. Yee, J. C. Zhu, W. Cha, S.-M. Kim, D.-J. Kim, H.-W. Kim, S.-L. Lee, C.-U. Lee, D.-J. Lee, Y. Park, B.-G. Pogge, R. W. Skowron, J. Mróz, P. Poleski, R. Koz owski, S. Soszy ski, I. Pietrukowicz, P. Szyma ski, M. K. Ulaczyk, K. Pawlak, M. Bryden, G. Beichman, C. Novati, S. Calchi Gaudi, B. S. Henderson, C. B. Jacklin, S. Penny, M. T. |
| description | We present microlensing planet OGLE-2017-BLG-0173Lb, with planet-host mass ratio of either or , the lowest or among the lowest ever detected. The planetary perturbation is strongly detected, Δχ2 ∼ 10000, because it arises from a bright (therefore, large) source passing over and enveloping the planetary caustic: a so-called "Hollywood" event. The factor ∼2.5 offset in q arises because of a previously unrecognized discrete degeneracy between Hollywood events in which the caustic is fully enveloped and those in which only one flank is enveloped, which we dub "Cannae" and "von Schlieffen," respectively. This degeneracy is "accidental" in that it arises from gaps in the data. Nevertheless, the fact that it appears in a Δχ2 = 10000 planetary anomaly is striking. We present a simple formalism to estimate the sensitivity of other Hollywood events to planets and show that they can lead to detections close to, but perhaps not quite reaching, the Earth/Sun mass ratio of . This formalism also enables an analytic understanding of the factor ∼2.5 offset in q between the Cannae and von Schlieffen solutions. The Bayesian estimates for the host mass, system distance, and planet-host projected separation are , , and , respectively. The two estimates of the planet mass are and . The measured lens-source relative proper motion will permit imaging of the lens in about 15 years or at first light on adaptive-optics imagers on next-generation telescopes. These will allow one to measure the host mass but probably will not be able to resolve the planet-host mass-ratio degeneracy. |
| doi_str_mv | 10.3847/1538-3881/aa992f |
| format | Article |
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D. ; Chung, S.-J. ; Gould, A. ; Han, C. ; Jung, Y. K. ; Shin, I.-G. ; Yee, J. C. ; Zhu, W. ; Cha, S.-M. ; Kim, D.-J. ; Kim, H.-W. ; Kim, S.-L. ; Lee, C.-U. ; Lee, D.-J. ; Lee, Y. ; Park, B.-G. ; Pogge, R. W. ; Skowron, J. ; Mróz, P. ; Poleski, R. ; Koz owski, S. ; Soszy ski, I. ; Pietrukowicz, P. ; Szyma ski, M. K. ; Ulaczyk, K. ; Pawlak, M. ; Bryden, G. ; Beichman, C. ; Novati, S. Calchi ; Gaudi, B. S. ; Henderson, C. B. ; Jacklin, S. ; Penny, M. T.</creator><creatorcontrib>Hwang, K.-H. ; Udalski, A. ; Shvartzvald, Y. ; Ryu, Y.-H. ; Albrow, M. D. ; Chung, S.-J. ; Gould, A. ; Han, C. ; Jung, Y. K. ; Shin, I.-G. ; Yee, J. C. ; Zhu, W. ; Cha, S.-M. ; Kim, D.-J. ; Kim, H.-W. ; Kim, S.-L. ; Lee, C.-U. ; Lee, D.-J. ; Lee, Y. ; Park, B.-G. ; Pogge, R. W. ; Skowron, J. ; Mróz, P. ; Poleski, R. ; Koz owski, S. ; Soszy ski, I. ; Pietrukowicz, P. ; Szyma ski, M. K. ; Ulaczyk, K. ; Pawlak, M. ; Bryden, G. ; Beichman, C. ; Novati, S. Calchi ; Gaudi, B. S. ; Henderson, C. B. ; Jacklin, S. ; Penny, M. T. ; UKIRT Microlensing Team ; OGLE Collaboration ; KMTNet Collaboration</creatorcontrib><description>We present microlensing planet OGLE-2017-BLG-0173Lb, with planet-host mass ratio of either or , the lowest or among the lowest ever detected. The planetary perturbation is strongly detected, Δχ2 ∼ 10000, because it arises from a bright (therefore, large) source passing over and enveloping the planetary caustic: a so-called "Hollywood" event. The factor ∼2.5 offset in q arises because of a previously unrecognized discrete degeneracy between Hollywood events in which the caustic is fully enveloped and those in which only one flank is enveloped, which we dub "Cannae" and "von Schlieffen," respectively. This degeneracy is "accidental" in that it arises from gaps in the data. Nevertheless, the fact that it appears in a Δχ2 = 10000 planetary anomaly is striking. We present a simple formalism to estimate the sensitivity of other Hollywood events to planets and show that they can lead to detections close to, but perhaps not quite reaching, the Earth/Sun mass ratio of . This formalism also enables an analytic understanding of the factor ∼2.5 offset in q between the Cannae and von Schlieffen solutions. The Bayesian estimates for the host mass, system distance, and planet-host projected separation are , , and , respectively. The two estimates of the planet mass are and . The measured lens-source relative proper motion will permit imaging of the lens in about 15 years or at first light on adaptive-optics imagers on next-generation telescopes. These will allow one to measure the host mass but probably will not be able to resolve the planet-host mass-ratio degeneracy.</description><identifier>ISSN: 0004-6256</identifier><identifier>EISSN: 1538-3881</identifier><identifier>DOI: 10.3847/1538-3881/aa992f</identifier><language>eng</language><publisher>Madison: The American Astronomical Society</publisher><subject>Adaptive optics ; Astronomy ; Formalism ; gravitational lensing: micro ; Microlenses ; Optics ; Perturbation ; planetary systems ; Planets ; Telescopes</subject><ispartof>The Astronomical journal, 2018-01, Vol.155 (1), p.20</ispartof><rights>2017. The American Astronomical Society. All rights reserved.</rights><rights>Copyright IOP Publishing Jan 2018</rights><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c416t-3635371b64e5342f9804bb74ec0d45b3d1e91831449816784a67e7363df5ad403</citedby><cites>FETCH-LOGICAL-c416t-3635371b64e5342f9804bb74ec0d45b3d1e91831449816784a67e7363df5ad403</cites><orcidid>0000-0001-9481-7123 ; 0000-0001-9823-2907 ; 0000-0001-8877-9060 ; 0000-0001-9504-8258 ; 0000-0002-9241-4117 ; 0000-0001-7506-5640 ; 0000-0003-3316-4012 ; 0000-0003-1435-3053 ; 0000-0002-2339-5899 ; 0000-0003-1525-5041 ; 0000-0003-0395-9869 ; 0000-0002-2335-1730</orcidid></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><linktopdf>$$Uhttps://iopscience.iop.org/article/10.3847/1538-3881/aa992f/pdf$$EPDF$$P50$$Giop$$H</linktopdf><link.rule.ids>314,776,780,27901,27902,38845,38867,53815,53842</link.rule.ids><linktorsrc>$$Uhttps://iopscience.iop.org/article/10.3847/1538-3881/aa992f$$EView_record_in_IOP_Publishing$$FView_record_in_$$GIOP_Publishing</linktorsrc></links><search><creatorcontrib>Hwang, K.-H.</creatorcontrib><creatorcontrib>Udalski, A.</creatorcontrib><creatorcontrib>Shvartzvald, Y.</creatorcontrib><creatorcontrib>Ryu, Y.-H.</creatorcontrib><creatorcontrib>Albrow, M. D.</creatorcontrib><creatorcontrib>Chung, S.-J.</creatorcontrib><creatorcontrib>Gould, A.</creatorcontrib><creatorcontrib>Han, C.</creatorcontrib><creatorcontrib>Jung, Y. K.</creatorcontrib><creatorcontrib>Shin, I.-G.</creatorcontrib><creatorcontrib>Yee, J. C.</creatorcontrib><creatorcontrib>Zhu, W.</creatorcontrib><creatorcontrib>Cha, S.-M.</creatorcontrib><creatorcontrib>Kim, D.-J.</creatorcontrib><creatorcontrib>Kim, H.-W.</creatorcontrib><creatorcontrib>Kim, S.-L.</creatorcontrib><creatorcontrib>Lee, C.-U.</creatorcontrib><creatorcontrib>Lee, D.-J.</creatorcontrib><creatorcontrib>Lee, Y.</creatorcontrib><creatorcontrib>Park, B.-G.</creatorcontrib><creatorcontrib>Pogge, R. 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T.</creatorcontrib><creatorcontrib>UKIRT Microlensing Team</creatorcontrib><creatorcontrib>OGLE Collaboration</creatorcontrib><creatorcontrib>KMTNet Collaboration</creatorcontrib><title>OGLE-2017-BLG-0173Lb: Low-mass-ratio Planet in a "Hollywood" Microlensing Event</title><title>The Astronomical journal</title><addtitle>AJ</addtitle><addtitle>Astron. J</addtitle><description>We present microlensing planet OGLE-2017-BLG-0173Lb, with planet-host mass ratio of either or , the lowest or among the lowest ever detected. The planetary perturbation is strongly detected, Δχ2 ∼ 10000, because it arises from a bright (therefore, large) source passing over and enveloping the planetary caustic: a so-called "Hollywood" event. The factor ∼2.5 offset in q arises because of a previously unrecognized discrete degeneracy between Hollywood events in which the caustic is fully enveloped and those in which only one flank is enveloped, which we dub "Cannae" and "von Schlieffen," respectively. This degeneracy is "accidental" in that it arises from gaps in the data. Nevertheless, the fact that it appears in a Δχ2 = 10000 planetary anomaly is striking. We present a simple formalism to estimate the sensitivity of other Hollywood events to planets and show that they can lead to detections close to, but perhaps not quite reaching, the Earth/Sun mass ratio of . This formalism also enables an analytic understanding of the factor ∼2.5 offset in q between the Cannae and von Schlieffen solutions. The Bayesian estimates for the host mass, system distance, and planet-host projected separation are , , and , respectively. The two estimates of the planet mass are and . The measured lens-source relative proper motion will permit imaging of the lens in about 15 years or at first light on adaptive-optics imagers on next-generation telescopes. These will allow one to measure the host mass but probably will not be able to resolve the planet-host mass-ratio degeneracy.</description><subject>Adaptive optics</subject><subject>Astronomy</subject><subject>Formalism</subject><subject>gravitational lensing: micro</subject><subject>Microlenses</subject><subject>Optics</subject><subject>Perturbation</subject><subject>planetary systems</subject><subject>Planets</subject><subject>Telescopes</subject><issn>0004-6256</issn><issn>1538-3881</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2018</creationdate><recordtype>article</recordtype><recordid>eNp1kM9LwzAcxYMoOKd3j2FejUua3950zE2o1IOeQ7qm0tE1M-kc--_NqOjJ04Mv773v4wPANcF3VDE5JZwqRJUiU2u1zuoTMPo9nYIRxpghkXFxDi5iXGNMiMJsBIpikc9RholEj_kCJaV5eQ9zv0cbGyMKtm88fG1t53rYdNDCydK37WHvfTWBL80q-NZ1sek-4PzLdf0lOKttG93Vj47B-9P8bbZEebF4nj3kaMWI6BEVlFNJSsEcpyyrdRpTlpK5Fa4YL2lFnCaKEsa0IkIqZoV0MqWqmtuKYToGN0PvNvjPnYu9Wftd6NJLk1HBhdJK6eTCgyvNjDG42mxDs7HhYAg2R2zmyMgcGZkBW4rcDpHGb_86_7V_A0OPaSg</recordid><startdate>20180101</startdate><enddate>20180101</enddate><creator>Hwang, K.-H.</creator><creator>Udalski, A.</creator><creator>Shvartzvald, Y.</creator><creator>Ryu, Y.-H.</creator><creator>Albrow, M. 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D. ; Chung, S.-J. ; Gould, A. ; Han, C. ; Jung, Y. K. ; Shin, I.-G. ; Yee, J. C. ; Zhu, W. ; Cha, S.-M. ; Kim, D.-J. ; Kim, H.-W. ; Kim, S.-L. ; Lee, C.-U. ; Lee, D.-J. ; Lee, Y. ; Park, B.-G. ; Pogge, R. W. ; Skowron, J. ; Mróz, P. ; Poleski, R. ; Koz owski, S. ; Soszy ski, I. ; Pietrukowicz, P. ; Szyma ski, M. K. ; Ulaczyk, K. ; Pawlak, M. ; Bryden, G. ; Beichman, C. ; Novati, S. Calchi ; Gaudi, B. S. ; Henderson, C. B. ; Jacklin, S. ; Penny, M. 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J</addtitle><date>2018-01-01</date><risdate>2018</risdate><volume>155</volume><issue>1</issue><spage>20</spage><pages>20-</pages><issn>0004-6256</issn><eissn>1538-3881</eissn><abstract>We present microlensing planet OGLE-2017-BLG-0173Lb, with planet-host mass ratio of either or , the lowest or among the lowest ever detected. The planetary perturbation is strongly detected, Δχ2 ∼ 10000, because it arises from a bright (therefore, large) source passing over and enveloping the planetary caustic: a so-called "Hollywood" event. The factor ∼2.5 offset in q arises because of a previously unrecognized discrete degeneracy between Hollywood events in which the caustic is fully enveloped and those in which only one flank is enveloped, which we dub "Cannae" and "von Schlieffen," respectively. This degeneracy is "accidental" in that it arises from gaps in the data. Nevertheless, the fact that it appears in a Δχ2 = 10000 planetary anomaly is striking. We present a simple formalism to estimate the sensitivity of other Hollywood events to planets and show that they can lead to detections close to, but perhaps not quite reaching, the Earth/Sun mass ratio of . This formalism also enables an analytic understanding of the factor ∼2.5 offset in q between the Cannae and von Schlieffen solutions. The Bayesian estimates for the host mass, system distance, and planet-host projected separation are , , and , respectively. The two estimates of the planet mass are and . The measured lens-source relative proper motion will permit imaging of the lens in about 15 years or at first light on adaptive-optics imagers on next-generation telescopes. These will allow one to measure the host mass but probably will not be able to resolve the planet-host mass-ratio degeneracy.</abstract><cop>Madison</cop><pub>The American Astronomical Society</pub><doi>10.3847/1538-3881/aa992f</doi><tpages>12</tpages><orcidid>https://orcid.org/0000-0001-9481-7123</orcidid><orcidid>https://orcid.org/0000-0001-9823-2907</orcidid><orcidid>https://orcid.org/0000-0001-8877-9060</orcidid><orcidid>https://orcid.org/0000-0001-9504-8258</orcidid><orcidid>https://orcid.org/0000-0002-9241-4117</orcidid><orcidid>https://orcid.org/0000-0001-7506-5640</orcidid><orcidid>https://orcid.org/0000-0003-3316-4012</orcidid><orcidid>https://orcid.org/0000-0003-1435-3053</orcidid><orcidid>https://orcid.org/0000-0002-2339-5899</orcidid><orcidid>https://orcid.org/0000-0003-1525-5041</orcidid><orcidid>https://orcid.org/0000-0003-0395-9869</orcidid><orcidid>https://orcid.org/0000-0002-2335-1730</orcidid><oa>free_for_read</oa></addata></record> |
| fulltext | fulltext_linktorsrc |
| identifier | ISSN: 0004-6256 |
| ispartof | The Astronomical journal, 2018-01, Vol.155 (1), p.20 |
| issn | 0004-6256 1538-3881 |
| language | eng |
| recordid | cdi_crossref_primary_10_3847_1538_3881_aa992f |
| source | IOP Publishing Free Content |
| subjects | Adaptive optics Astronomy Formalism gravitational lensing: micro Microlenses Optics Perturbation planetary systems Planets Telescopes |
| title | OGLE-2017-BLG-0173Lb: Low-mass-ratio Planet in a "Hollywood" Microlensing Event |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-02-21T17%3A17%3A49IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-proquest_O3W&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=OGLE-2017-BLG-0173Lb:%20Low-mass-ratio%20Planet%20in%20a%20%22Hollywood%22%20Microlensing%20Event&rft.jtitle=The%20Astronomical%20journal&rft.au=Hwang,%20K.-H.&rft.aucorp=UKIRT%C2%A0Microlensing%C2%A0Team&rft.date=2018-01-01&rft.volume=155&rft.issue=1&rft.spage=20&rft.pages=20-&rft.issn=0004-6256&rft.eissn=1538-3881&rft_id=info:doi/10.3847/1538-3881/aa992f&rft_dat=%3Cproquest_O3W%3E2365689889%3C/proquest_O3W%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_pqid=2365689889&rft_id=info:pmid/&rfr_iscdi=true |