A Caltech Library Service

MOA-2007-BLG-400 A Super-Jupiter-mass Planet Orbiting a Galactic Bulge K-dwarf Revealed by Keck Adaptive Optics Imaging

Bhattacharya, Aparna and Bennett, David P. and Beaulieu, Jean Philippe and Bond, Ian A. and Koshimoto, Naoki and Lu, Jessica R. and Blackman, Joshua W. and Vandorou, Aikaterini and Terry, Sean K. and Batista, Virginie and Marquette, Jean Baptiste and Cole, Andrew A. and Fukui, Akihiko and Henderson, Calen B. and Ranc, ‪Clément (2021) MOA-2007-BLG-400 A Super-Jupiter-mass Planet Orbiting a Galactic Bulge K-dwarf Revealed by Keck Adaptive Optics Imaging. Astronomical Journal, 162 (2). Art. No. 60. ISSN 0004-6256. doi:10.3847/1538-3881/abfec5.

[img] PDF - Published Version
See Usage Policy.

[img] PDF - Submitted Version
See Usage Policy.


Use this Persistent URL to link to this item:


We present Keck/NIRC2 adaptive optics imaging of planetary microlensing event MOA-2007-BLG-400 that resolves the lens star system from the source. We find that the MOA-2007-BLG-400L planetary system consists of a 1.71 ± 0.27 M_(Jup) planet orbiting a 0.69 ± 0.04 M_⊙ K-dwarf host star at a distance of 6.89 ± 0.77 kpc from the Sun. So, this planetary system probably resides in the Galactic bulge. The planet–host star projected separation is only weakly constrained due to the close-wide light-curve degeneracy; the 2σ projected separation ranges are 0.6–1.0 au and 4.7–7.7 au for close and wide solutions, respectively. This host mass is at the top end of the range of masses predicted by a standard Bayesian analysis. Our Keck follow-up program has now measured lens-source separations for six planetary microlensing events, and five of these six events have host star masses above the median prediction under the assumption that assumes that all stars have an equal chance of hosting planets detectable by microlensing. This suggests that more massive stars may be more likely to host planets of a fixed mass ratio that orbit near or beyond the snow line. These results also indicate the importance of host star mass measurements for exoplanets found by microlensing. The microlensing survey imaging data from NASA's Nancy Grace Roman Space Telescope (formerly WFIRST) mission will be doing mass measurements like this for a huge number of planetary events.

Item Type:Article
Related URLs:
URLURL TypeDescription Paper
Bennett, David P.0000-0001-8043-8413
Beaulieu, Jean Philippe0000-0003-0014-3354
Koshimoto, Naoki0000-0003-2302-9562
Lu, Jessica R.0000-0001-9611-0009
Blackman, Joshua W.0000-0001-5860-1157
Vandorou, Aikaterini0000-0002-9881-4760
Terry, Sean K.0000-0002-5029-3257
Batista, Virginie0000-0002-9782-0333
Marquette, Jean Baptiste0000-0002-7901-7213
Cole, Andrew A.0000-0003-0303-3855
Fukui, Akihiko0000-0002-4909-5763
Henderson, Calen B.0000-0001-8877-9060
Ranc, ‪Clément0000-0003-2388-4534
Additional Information:© 2021. The American Astronomical Society. Received 2020 September 4; revised 2021 April 20; accepted 2021 May 5; published 2021 July 15. This work has made use of data from the Astro Data Lab at Natioanal Science Foundation's OIR Lab, which is operated by the Association of Universities for Research in Astronomy (AURA), Inc. under a cooperative agreement with the National Science Foundation. We also acknowledge the help of Dr. Peter Stetson, which provided us with feedback on our analysis of Keck data. The Keck Telescope observations and analysis were supported by a NASA Keck PI Data Award 80NSSC18K0793. Data presented herein were obtained at the W. M. Keck Observatory from telescope time allocated to NASA through the agency's scientific partnership with the California Institute of Technology and the University of California. The Observatory was made possible by the generous financial support of the W. M. Keck Foundation. D.P.B., A.B., N.K., and S.K.T. were also supported by NASA through grant NASA-80NSSC18K0274 and by NASA award No. 80GSFC17M0002. This work was supported by the University of Tasmania through the UTAS Foundation and the endowed Warren Chair in Astronomy and the ANR COLD- WORLDS (ANR-18-CE31-0002). This research was also supported in part by the Australian Government through the Australian Research Council Discovery Program (project No. 200101909) grant awarded to A.A.C. and J.P.B.. Work by N.K. is supported by JSPS KAKENHI grant No. JP18J00897. A.F.'s work was partly supported by JSPS KAKENHI grant No. JP17H02871.
Group:Infrared Processing and Analysis Center (IPAC)
Funding AgencyGrant Number
W. M. Keck FoundationUNSPECIFIED
University of TasmaniaUNSPECIFIED
Agence Nationale pour la Recherche (ANR)ANR-18-CE31-0002
Australian Research Council200101909
Japan Society for the Promotion of Science (JSPS)JP18J00897
Japan Society for the Promotion of Science (JSPS)JP17H02871
Subject Keywords:Exoplanets; High-resolution microlensing event imaging; Gravitational microlensing
Issue or Number:2
Classification Code:Unified Astronomy Thesaurus concepts: Exoplanets (498); High-resolution microlensing event imaging (2138); Gravitational microlensing (672)
Record Number:CaltechAUTHORS:20210726-231115574
Persistent URL:
Official Citation:Aparna Bhattacharya et al 2021 AJ 162 60
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:110020
Deposited By: Tony Diaz
Deposited On:28 Jul 2021 17:33
Last Modified:28 Jul 2021 17:33

Repository Staff Only: item control page