Moa-2010-BLG-073L

An m-dwarf with a substellar companion at the planet/brown dwarf boundary

R. A. Street, J. Y. Choi, Y. Tsapras, C. Han, K. Furusawa, M. Hundertmark, A. Gould, T. Sumi, I. A. Bond, D. Wouters, R. Zellem, A. Udalski, C. Snodgrass, K. Horne, M. Dominik, P. Browne, N. Kains, D. M. Bramich, D. Bajek, I. A. Steele & 112 others S. Ipatov, F. Abe, D. P. Bennett, C. S. Botzler, P. Chote, M. Freeman, A. Fukui, P. Harris, Y. Itow, C. H. Ling, K. Masuda, Y. Matsubara, N. Miyake, Y. Muraki, T. Nagayama, S. Nishimaya, K. Ohnishi, N. Rattenbury, To Saito, D. J. Sullivan, D. Suzuki, W. L. Sweatman, P. J. Tristram, K. Wada, P. C M Yock, M. K. Szymański, M. Kubiak, G. Pietrzyński, I. Soszyński, R. Poleski, K. Ulaczyk, Wyrzykowski, J. Yee, S. Dong, I. G. Shin, C. U. Lee, J. Skowron, L. Andrade De Almeida, D. L. Depoy, B. S. Gaudi, L. W. Hung, F. Jablonski, S. Kaspi, N. Klein, K. H. Hwang, J. R. Koo, D. Maoz, J. A. Muñoz, R. W. Pogge, D. Polishhook, A. Shporer, J. McCormick, G. Christie, T. Natusch, B. Allen, J. Drummond, D. Moorhouse, G. Thornley, M. Knowler, M. Bos, G. Bolt, J. P. Beaulieu, M. D. Albrow, V. Batista, S. Brillant, J. A R Caldwell, A. Cassan, A. Cole, E. Corrales, Ch Coutures, S. Dieters, D. Dominis Prester, J. Donatowicz, P. Fouqué, E. Bachelet, J. Greenhill, S. R. Kane, D. Kubas, J. B. Marquette, R. Martin, J. Menzies, K. R. Pollard, K. C. Sahu, J. Wambsganss, A. Williams, M. Zub, Khalid Al-Subai, V. Bozza, M. J. Burgdorf, S. Calchi Novati, P. Dodds, S. Dreizler, F. Finet, T. Gerner, S. Hardis, K. Harpsøe, F. Hessman, T. C. Hinse, U. G. Jørgensen, E. Kerins, C. Liebig, L. Mancini, M. Mathiasen, M. T. Penny, S. Proft, S. Rahvar, D. Ricci, G. Scarpetta, S. Schäfer, F. Schönebeck, J. Southworth, J. Surdej

Research output: Contribution to journalArticle

26 Citations (Scopus)

Abstract

We present an analysis of the anomalous microlensing event, MOA-2010-BLG-073, announced by the Microlensing Observations in Astrophysics survey on 2010 March 18. This event was remarkable because the source was previously known to be photometrically variable. Analyzing the pre-event source light curve, we demonstrate that it is an irregular variable over timescales >200 days. Its dereddened color, (V-I)S, 0, is 1.221 ± 0.051 mag, and from our lens model we derive a source radius of 14.7 ± 1.3 R, suggesting that it is a red giant star. We initially explored a number of purely microlensing models for the event but found a residual gradient in the data taken prior to and after the event. This is likely to be due to the variability of the source rather than part of the lensing event, so we incorporated a slope parameter in our model in order to derive the true parameters of the lensing system. We find that the lensing system has a mass ratio of q = 0.0654 ± 0.0006. The Einstein crossing time of the event, tE = 44.3 ± 0.1 days, was sufficiently long that the light curve exhibited parallax effects. In addition, the source trajectory relative to the large caustic structure allowed the orbital motion of the lens system to be detected. Combining the parallax with the Einstein radius, we were able to derive the distance to the lens, DL = 2.8 ± 0.4 kpc, and the masses of the lensing objects. The primary of the lens is an M-dwarf with ML,1 = 0.16 ± 0.03 M, while the companion has ML,2 = 11.0 ± 2.0 MJ, putting it in the boundary zone between planets and brown dwarfs.

Original languageEnglish
Article number67
JournalAstrophysical Journal
Volume763
Issue number1
DOIs
Publication statusPublished - 20 Jan 2013

Fingerprint

planets
planet
lenses
astrophysics
parallax
light curve
trajectory
timescale
red giant stars
radii
mass ratios
alkalies
trajectories
slopes
parameter
orbits
color
gradients
effect
analysis

Keywords

  • brown dwarfs
  • gravitational lensing: micro
  • planetary systems
  • planets and satellites: formation
  • planets and satellites: general
  • techniques: photometric

ASJC Scopus subject areas

  • Space and Planetary Science
  • Astronomy and Astrophysics

Cite this

Street, R. A., Choi, J. Y., Tsapras, Y., Han, C., Furusawa, K., Hundertmark, M., ... Surdej, J. (2013). Moa-2010-BLG-073L: An m-dwarf with a substellar companion at the planet/brown dwarf boundary. Astrophysical Journal, 763(1), [67]. https://doi.org/10.1088/0004-637X/763/1/67

Moa-2010-BLG-073L : An m-dwarf with a substellar companion at the planet/brown dwarf boundary. / Street, R. A.; Choi, J. Y.; Tsapras, Y.; Han, C.; Furusawa, K.; Hundertmark, M.; Gould, A.; Sumi, T.; Bond, I. A.; Wouters, D.; Zellem, R.; Udalski, A.; Snodgrass, C.; Horne, K.; Dominik, M.; Browne, P.; Kains, N.; Bramich, D. M.; Bajek, D.; Steele, I. A.; Ipatov, S.; Abe, F.; Bennett, D. P.; Botzler, C. S.; Chote, P.; Freeman, M.; Fukui, A.; Harris, P.; Itow, Y.; Ling, C. H.; Masuda, K.; Matsubara, Y.; Miyake, N.; Muraki, Y.; Nagayama, T.; Nishimaya, S.; Ohnishi, K.; Rattenbury, N.; Saito, To; Sullivan, D. J.; Suzuki, D.; Sweatman, W. L.; Tristram, P. J.; Wada, K.; Yock, P. C M; Szymański, M. K.; Kubiak, M.; Pietrzyński, G.; Soszyński, I.; Poleski, R.; Ulaczyk, K.; Wyrzykowski; Yee, J.; Dong, S.; Shin, I. G.; Lee, C. U.; Skowron, J.; Andrade De Almeida, L.; Depoy, D. L.; Gaudi, B. S.; Hung, L. W.; Jablonski, F.; Kaspi, S.; Klein, N.; Hwang, K. H.; Koo, J. R.; Maoz, D.; Muñoz, J. A.; Pogge, R. W.; Polishhook, D.; Shporer, A.; McCormick, J.; Christie, G.; Natusch, T.; Allen, B.; Drummond, J.; Moorhouse, D.; Thornley, G.; Knowler, M.; Bos, M.; Bolt, G.; Beaulieu, J. P.; Albrow, M. D.; Batista, V.; Brillant, S.; Caldwell, J. A R; Cassan, A.; Cole, A.; Corrales, E.; Coutures, Ch; Dieters, S.; Dominis Prester, D.; Donatowicz, J.; Fouqué, P.; Bachelet, E.; Greenhill, J.; Kane, S. R.; Kubas, D.; Marquette, J. B.; Martin, R.; Menzies, J.; Pollard, K. R.; Sahu, K. C.; Wambsganss, J.; Williams, A.; Zub, M.; Al-Subai, Khalid; Bozza, V.; Burgdorf, M. J.; Calchi Novati, S.; Dodds, P.; Dreizler, S.; Finet, F.; Gerner, T.; Hardis, S.; Harpsøe, K.; Hessman, F.; Hinse, T. C.; Jørgensen, U. G.; Kerins, E.; Liebig, C.; Mancini, L.; Mathiasen, M.; Penny, M. T.; Proft, S.; Rahvar, S.; Ricci, D.; Scarpetta, G.; Schäfer, S.; Schönebeck, F.; Southworth, J.; Surdej, J.

In: Astrophysical Journal, Vol. 763, No. 1, 67, 20.01.2013.

Research output: Contribution to journalArticle

Street, RA, Choi, JY, Tsapras, Y, Han, C, Furusawa, K, Hundertmark, M, Gould, A, Sumi, T, Bond, IA, Wouters, D, Zellem, R, Udalski, A, Snodgrass, C, Horne, K, Dominik, M, Browne, P, Kains, N, Bramich, DM, Bajek, D, Steele, IA, Ipatov, S, Abe, F, Bennett, DP, Botzler, CS, Chote, P, Freeman, M, Fukui, A, Harris, P, Itow, Y, Ling, CH, Masuda, K, Matsubara, Y, Miyake, N, Muraki, Y, Nagayama, T, Nishimaya, S, Ohnishi, K, Rattenbury, N, Saito, T, Sullivan, DJ, Suzuki, D, Sweatman, WL, Tristram, PJ, Wada, K, Yock, PCM, Szymański, MK, Kubiak, M, Pietrzyński, G, Soszyński, I, Poleski, R, Ulaczyk, K, Wyrzykowski, Yee, J, Dong, S, Shin, IG, Lee, CU, Skowron, J, Andrade De Almeida, L, Depoy, DL, Gaudi, BS, Hung, LW, Jablonski, F, Kaspi, S, Klein, N, Hwang, KH, Koo, JR, Maoz, D, Muñoz, JA, Pogge, RW, Polishhook, D, Shporer, A, McCormick, J, Christie, G, Natusch, T, Allen, B, Drummond, J, Moorhouse, D, Thornley, G, Knowler, M, Bos, M, Bolt, G, Beaulieu, JP, Albrow, MD, Batista, V, Brillant, S, Caldwell, JAR, Cassan, A, Cole, A, Corrales, E, Coutures, C, Dieters, S, Dominis Prester, D, Donatowicz, J, Fouqué, P, Bachelet, E, Greenhill, J, Kane, SR, Kubas, D, Marquette, JB, Martin, R, Menzies, J, Pollard, KR, Sahu, KC, Wambsganss, J, Williams, A, Zub, M, Al-Subai, K, Bozza, V, Burgdorf, MJ, Calchi Novati, S, Dodds, P, Dreizler, S, Finet, F, Gerner, T, Hardis, S, Harpsøe, K, Hessman, F, Hinse, TC, Jørgensen, UG, Kerins, E, Liebig, C, Mancini, L, Mathiasen, M, Penny, MT, Proft, S, Rahvar, S, Ricci, D, Scarpetta, G, Schäfer, S, Schönebeck, F, Southworth, J & Surdej, J 2013, 'Moa-2010-BLG-073L: An m-dwarf with a substellar companion at the planet/brown dwarf boundary', Astrophysical Journal, vol. 763, no. 1, 67. https://doi.org/10.1088/0004-637X/763/1/67
Street, R. A. ; Choi, J. Y. ; Tsapras, Y. ; Han, C. ; Furusawa, K. ; Hundertmark, M. ; Gould, A. ; Sumi, T. ; Bond, I. A. ; Wouters, D. ; Zellem, R. ; Udalski, A. ; Snodgrass, C. ; Horne, K. ; Dominik, M. ; Browne, P. ; Kains, N. ; Bramich, D. M. ; Bajek, D. ; Steele, I. A. ; Ipatov, S. ; Abe, F. ; Bennett, D. P. ; Botzler, C. S. ; Chote, P. ; Freeman, M. ; Fukui, A. ; Harris, P. ; Itow, Y. ; Ling, C. H. ; Masuda, K. ; Matsubara, Y. ; Miyake, N. ; Muraki, Y. ; Nagayama, T. ; Nishimaya, S. ; Ohnishi, K. ; Rattenbury, N. ; Saito, To ; Sullivan, D. J. ; Suzuki, D. ; Sweatman, W. L. ; Tristram, P. J. ; Wada, K. ; Yock, P. C M ; Szymański, M. K. ; Kubiak, M. ; Pietrzyński, G. ; Soszyński, I. ; Poleski, R. ; Ulaczyk, K. ; Wyrzykowski ; Yee, J. ; Dong, S. ; Shin, I. G. ; Lee, C. U. ; Skowron, J. ; Andrade De Almeida, L. ; Depoy, D. L. ; Gaudi, B. S. ; Hung, L. W. ; Jablonski, F. ; Kaspi, S. ; Klein, N. ; Hwang, K. H. ; Koo, J. R. ; Maoz, D. ; Muñoz, J. A. ; Pogge, R. W. ; Polishhook, D. ; Shporer, A. ; McCormick, J. ; Christie, G. ; Natusch, T. ; Allen, B. ; Drummond, J. ; Moorhouse, D. ; Thornley, G. ; Knowler, M. ; Bos, M. ; Bolt, G. ; Beaulieu, J. P. ; Albrow, M. D. ; Batista, V. ; Brillant, S. ; Caldwell, J. A R ; Cassan, A. ; Cole, A. ; Corrales, E. ; Coutures, Ch ; Dieters, S. ; Dominis Prester, D. ; Donatowicz, J. ; Fouqué, P. ; Bachelet, E. ; Greenhill, J. ; Kane, S. R. ; Kubas, D. ; Marquette, J. B. ; Martin, R. ; Menzies, J. ; Pollard, K. R. ; Sahu, K. C. ; Wambsganss, J. ; Williams, A. ; Zub, M. ; Al-Subai, Khalid ; Bozza, V. ; Burgdorf, M. J. ; Calchi Novati, S. ; Dodds, P. ; Dreizler, S. ; Finet, F. ; Gerner, T. ; Hardis, S. ; Harpsøe, K. ; Hessman, F. ; Hinse, T. C. ; Jørgensen, U. G. ; Kerins, E. ; Liebig, C. ; Mancini, L. ; Mathiasen, M. ; Penny, M. T. ; Proft, S. ; Rahvar, S. ; Ricci, D. ; Scarpetta, G. ; Schäfer, S. ; Schönebeck, F. ; Southworth, J. ; Surdej, J. / Moa-2010-BLG-073L : An m-dwarf with a substellar companion at the planet/brown dwarf boundary. In: Astrophysical Journal. 2013 ; Vol. 763, No. 1.
@article{cd0c471c3928461eb7f4c6477cb05bde,
title = "Moa-2010-BLG-073L: An m-dwarf with a substellar companion at the planet/brown dwarf boundary",
abstract = "We present an analysis of the anomalous microlensing event, MOA-2010-BLG-073, announced by the Microlensing Observations in Astrophysics survey on 2010 March 18. This event was remarkable because the source was previously known to be photometrically variable. Analyzing the pre-event source light curve, we demonstrate that it is an irregular variable over timescales >200 days. Its dereddened color, (V-I)S, 0, is 1.221 ± 0.051 mag, and from our lens model we derive a source radius of 14.7 ± 1.3 R⊙, suggesting that it is a red giant star. We initially explored a number of purely microlensing models for the event but found a residual gradient in the data taken prior to and after the event. This is likely to be due to the variability of the source rather than part of the lensing event, so we incorporated a slope parameter in our model in order to derive the true parameters of the lensing system. We find that the lensing system has a mass ratio of q = 0.0654 ± 0.0006. The Einstein crossing time of the event, tE = 44.3 ± 0.1 days, was sufficiently long that the light curve exhibited parallax effects. In addition, the source trajectory relative to the large caustic structure allowed the orbital motion of the lens system to be detected. Combining the parallax with the Einstein radius, we were able to derive the distance to the lens, DL = 2.8 ± 0.4 kpc, and the masses of the lensing objects. The primary of the lens is an M-dwarf with ML,1 = 0.16 ± 0.03 M⊙, while the companion has ML,2 = 11.0 ± 2.0 MJ, putting it in the boundary zone between planets and brown dwarfs.",
keywords = "brown dwarfs, gravitational lensing: micro, planetary systems, planets and satellites: formation, planets and satellites: general, techniques: photometric",
author = "Street, {R. A.} and Choi, {J. Y.} and Y. Tsapras and C. Han and K. Furusawa and M. Hundertmark and A. Gould and T. Sumi and Bond, {I. A.} and D. Wouters and R. Zellem and A. Udalski and C. Snodgrass and K. Horne and M. Dominik and P. Browne and N. Kains and Bramich, {D. M.} and D. Bajek and Steele, {I. A.} and S. Ipatov and F. Abe and Bennett, {D. P.} and Botzler, {C. S.} and P. Chote and M. Freeman and A. Fukui and P. Harris and Y. Itow and Ling, {C. H.} and K. Masuda and Y. Matsubara and N. Miyake and Y. Muraki and T. Nagayama and S. Nishimaya and K. Ohnishi and N. Rattenbury and To Saito and Sullivan, {D. J.} and D. Suzuki and Sweatman, {W. L.} and Tristram, {P. J.} and K. Wada and Yock, {P. C M} and Szymański, {M. K.} and M. Kubiak and G. Pietrzyński and I. Soszyński and R. Poleski and K. Ulaczyk and Wyrzykowski and J. Yee and S. Dong and Shin, {I. G.} and Lee, {C. U.} and J. Skowron and {Andrade De Almeida}, L. and Depoy, {D. L.} and Gaudi, {B. S.} and Hung, {L. W.} and F. Jablonski and S. Kaspi and N. Klein and Hwang, {K. H.} and Koo, {J. R.} and D. Maoz and Mu{\~n}oz, {J. A.} and Pogge, {R. W.} and D. Polishhook and A. Shporer and J. McCormick and G. Christie and T. Natusch and B. Allen and J. Drummond and D. Moorhouse and G. Thornley and M. Knowler and M. Bos and G. Bolt and Beaulieu, {J. P.} and Albrow, {M. D.} and V. Batista and S. Brillant and Caldwell, {J. A R} and A. Cassan and A. Cole and E. Corrales and Ch Coutures and S. Dieters and {Dominis Prester}, D. and J. Donatowicz and P. Fouqu{\'e} and E. Bachelet and J. Greenhill and Kane, {S. R.} and D. Kubas and Marquette, {J. B.} and R. Martin and J. Menzies and Pollard, {K. R.} and Sahu, {K. C.} and J. Wambsganss and A. Williams and M. Zub and Khalid Al-Subai and V. Bozza and Burgdorf, {M. J.} and {Calchi Novati}, S. and P. Dodds and S. Dreizler and F. Finet and T. Gerner and S. Hardis and K. Harps{\o}e and F. Hessman and Hinse, {T. C.} and J{\o}rgensen, {U. G.} and E. Kerins and C. Liebig and L. Mancini and M. Mathiasen and Penny, {M. T.} and S. Proft and S. Rahvar and D. Ricci and G. Scarpetta and S. Sch{\"a}fer and F. Sch{\"o}nebeck and J. Southworth and J. Surdej",
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month = "1",
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doi = "10.1088/0004-637X/763/1/67",
language = "English",
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TY - JOUR

T1 - Moa-2010-BLG-073L

T2 - An m-dwarf with a substellar companion at the planet/brown dwarf boundary

AU - Street, R. A.

AU - Choi, J. Y.

AU - Tsapras, Y.

AU - Han, C.

AU - Furusawa, K.

AU - Hundertmark, M.

AU - Gould, A.

AU - Sumi, T.

AU - Bond, I. A.

AU - Wouters, D.

AU - Zellem, R.

AU - Udalski, A.

AU - Snodgrass, C.

AU - Horne, K.

AU - Dominik, M.

AU - Browne, P.

AU - Kains, N.

AU - Bramich, D. M.

AU - Bajek, D.

AU - Steele, I. A.

AU - Ipatov, S.

AU - Abe, F.

AU - Bennett, D. P.

AU - Botzler, C. S.

AU - Chote, P.

AU - Freeman, M.

AU - Fukui, A.

AU - Harris, P.

AU - Itow, Y.

AU - Ling, C. H.

AU - Masuda, K.

AU - Matsubara, Y.

AU - Miyake, N.

AU - Muraki, Y.

AU - Nagayama, T.

AU - Nishimaya, S.

AU - Ohnishi, K.

AU - Rattenbury, N.

AU - Saito, To

AU - Sullivan, D. J.

AU - Suzuki, D.

AU - Sweatman, W. L.

AU - Tristram, P. J.

AU - Wada, K.

AU - Yock, P. C M

AU - Szymański, M. K.

AU - Kubiak, M.

AU - Pietrzyński, G.

AU - Soszyński, I.

AU - Poleski, R.

AU - Ulaczyk, K.

AU - Wyrzykowski,

AU - Yee, J.

AU - Dong, S.

AU - Shin, I. G.

AU - Lee, C. U.

AU - Skowron, J.

AU - Andrade De Almeida, L.

AU - Depoy, D. L.

AU - Gaudi, B. S.

AU - Hung, L. W.

AU - Jablonski, F.

AU - Kaspi, S.

AU - Klein, N.

AU - Hwang, K. H.

AU - Koo, J. R.

AU - Maoz, D.

AU - Muñoz, J. A.

AU - Pogge, R. W.

AU - Polishhook, D.

AU - Shporer, A.

AU - McCormick, J.

AU - Christie, G.

AU - Natusch, T.

AU - Allen, B.

AU - Drummond, J.

AU - Moorhouse, D.

AU - Thornley, G.

AU - Knowler, M.

AU - Bos, M.

AU - Bolt, G.

AU - Beaulieu, J. P.

AU - Albrow, M. D.

AU - Batista, V.

AU - Brillant, S.

AU - Caldwell, J. A R

AU - Cassan, A.

AU - Cole, A.

AU - Corrales, E.

AU - Coutures, Ch

AU - Dieters, S.

AU - Dominis Prester, D.

AU - Donatowicz, J.

AU - Fouqué, P.

AU - Bachelet, E.

AU - Greenhill, J.

AU - Kane, S. R.

AU - Kubas, D.

AU - Marquette, J. B.

AU - Martin, R.

AU - Menzies, J.

AU - Pollard, K. R.

AU - Sahu, K. C.

AU - Wambsganss, J.

AU - Williams, A.

AU - Zub, M.

AU - Al-Subai, Khalid

AU - Bozza, V.

AU - Burgdorf, M. J.

AU - Calchi Novati, S.

AU - Dodds, P.

AU - Dreizler, S.

AU - Finet, F.

AU - Gerner, T.

AU - Hardis, S.

AU - Harpsøe, K.

AU - Hessman, F.

AU - Hinse, T. C.

AU - Jørgensen, U. G.

AU - Kerins, E.

AU - Liebig, C.

AU - Mancini, L.

AU - Mathiasen, M.

AU - Penny, M. T.

AU - Proft, S.

AU - Rahvar, S.

AU - Ricci, D.

AU - Scarpetta, G.

AU - Schäfer, S.

AU - Schönebeck, F.

AU - Southworth, J.

AU - Surdej, J.

PY - 2013/1/20

Y1 - 2013/1/20

N2 - We present an analysis of the anomalous microlensing event, MOA-2010-BLG-073, announced by the Microlensing Observations in Astrophysics survey on 2010 March 18. This event was remarkable because the source was previously known to be photometrically variable. Analyzing the pre-event source light curve, we demonstrate that it is an irregular variable over timescales >200 days. Its dereddened color, (V-I)S, 0, is 1.221 ± 0.051 mag, and from our lens model we derive a source radius of 14.7 ± 1.3 R⊙, suggesting that it is a red giant star. We initially explored a number of purely microlensing models for the event but found a residual gradient in the data taken prior to and after the event. This is likely to be due to the variability of the source rather than part of the lensing event, so we incorporated a slope parameter in our model in order to derive the true parameters of the lensing system. We find that the lensing system has a mass ratio of q = 0.0654 ± 0.0006. The Einstein crossing time of the event, tE = 44.3 ± 0.1 days, was sufficiently long that the light curve exhibited parallax effects. In addition, the source trajectory relative to the large caustic structure allowed the orbital motion of the lens system to be detected. Combining the parallax with the Einstein radius, we were able to derive the distance to the lens, DL = 2.8 ± 0.4 kpc, and the masses of the lensing objects. The primary of the lens is an M-dwarf with ML,1 = 0.16 ± 0.03 M⊙, while the companion has ML,2 = 11.0 ± 2.0 MJ, putting it in the boundary zone between planets and brown dwarfs.

AB - We present an analysis of the anomalous microlensing event, MOA-2010-BLG-073, announced by the Microlensing Observations in Astrophysics survey on 2010 March 18. This event was remarkable because the source was previously known to be photometrically variable. Analyzing the pre-event source light curve, we demonstrate that it is an irregular variable over timescales >200 days. Its dereddened color, (V-I)S, 0, is 1.221 ± 0.051 mag, and from our lens model we derive a source radius of 14.7 ± 1.3 R⊙, suggesting that it is a red giant star. We initially explored a number of purely microlensing models for the event but found a residual gradient in the data taken prior to and after the event. This is likely to be due to the variability of the source rather than part of the lensing event, so we incorporated a slope parameter in our model in order to derive the true parameters of the lensing system. We find that the lensing system has a mass ratio of q = 0.0654 ± 0.0006. The Einstein crossing time of the event, tE = 44.3 ± 0.1 days, was sufficiently long that the light curve exhibited parallax effects. In addition, the source trajectory relative to the large caustic structure allowed the orbital motion of the lens system to be detected. Combining the parallax with the Einstein radius, we were able to derive the distance to the lens, DL = 2.8 ± 0.4 kpc, and the masses of the lensing objects. The primary of the lens is an M-dwarf with ML,1 = 0.16 ± 0.03 M⊙, while the companion has ML,2 = 11.0 ± 2.0 MJ, putting it in the boundary zone between planets and brown dwarfs.

KW - brown dwarfs

KW - gravitational lensing: micro

KW - planetary systems

KW - planets and satellites: formation

KW - planets and satellites: general

KW - techniques: photometric

UR - http://www.scopus.com/inward/record.url?scp=84872239600&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=84872239600&partnerID=8YFLogxK

U2 - 10.1088/0004-637X/763/1/67

DO - 10.1088/0004-637X/763/1/67

M3 - Article

VL - 763

JO - Astrophysical Journal

JF - Astrophysical Journal

SN - 0004-637X

IS - 1

M1 - 67

ER -