NGTS-2b: An inflated hot-Jupiter transiting a bright F-dwarf

Liam Raynard; Michael R. Goad; Edward Gillen; Louise D. Nielsen; Christopher A. Watson; Andrew P. G. Thompson; James McCormac; Daniel Bayliss; Maritza Soto; Szilard Csizmadia; Alexander Chaushev; Matthew R. Burleigh; Richard Alexander; David J. Armstrong; François Bouchy; Joshua T. Briegal; Juan Cabrera; Sarah L. Casewell; Bruno Chazelas; Benjamin F. Cooke; Philipp Eigmüller; Anders Erikson; Boris T. Gänsicke; Andrew Grange; Maximilian N. Günther; Simon T. Hodgkin; Matthew J. Hooton; James S. Jenkins; Gregory Lambert; Tom Louden; Lionel Metrailler; Maximiliano Moyano; Don Pollacco; Katja Poppenhaeger; Didier Queloz; Roberto Raddi; Heike Rauer; Andrew M. Read; Barry Smalley; Alexis M. S. Smith; Oliver Turner; Stéphane Udry; Simon R. Walker; Richard G. West; Peter J. Wheatley

doi:10.1093/mnras/sty2581

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arXiv · 1805.10449

NGTS-2b: An inflated hot-Jupiter transiting a bright F-dwarf

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Abstract

We report the discovery of NGTS-2b, an inflated hot-Jupiter transiting a bright F5V star (2MASS J14202949-3112074; $T_{\rm eff}$=$6478^{+94}_{-89}$ K), discovered as part of the Next Generation Transit Survey (NGTS). The planet is in a P=4.51 day orbit with mass $0.74^{+0.13}_{-0.12}$ M$_{J}$, radius $1.595^{+0.047}_{-0.045}$ R$_{J}$ and density $0.226^{+0.040}_{-0.038}$ g cm$^{-3}$; therefore one of the lowest density exoplanets currently known. With a relatively deep 1.0% transit around a bright V=10.96 host star, NGTS-2b is a prime target for probing giant planet composition via atmospheric transmission spectroscopy. The rapid rotation ($vsin$i=$15.2\pm0.8$ km s$^{-1}$) also makes this system an excellent candidate for Rossiter-McLaughlin follow-up observations, to measure the sky-projected stellar obliquity. NGTS-2b was confirmed without the need for follow-up photometry, due to the high precision of the NGTS photometry.

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Liam Raynard, Michael R. Goad, Edward Gillen, Louise D. Nielsen, Christopher A. Watson, Andrew P. G. Thompson, James McCormac, Daniel Bayliss, Maritza Soto, Szilard Csizmadia, Alexander Chaushev, Matthew R. Burleigh, Richard Alexander, David J. Armstrong, François Bouchy, Joshua T. Briegal, Juan Cabrera, Sarah L. Casewell, Bruno Chazelas, Benjamin F. Cooke, Philipp Eigmüller, Anders Erikson, Boris T. Gänsicke, Andrew Grange, Maximilian N. Günther, Simon T. Hodgkin, Matthew J. Hooton, James S. Jenkins, Gregory Lambert, Tom Louden, Lionel Metrailler, Maximiliano Moyano, Don Pollacco, Katja Poppenhaeger, Didier Queloz, Roberto Raddi, Heike Rauer, Andrew M. Read, Barry Smalley, Alexis M. S. Smith, Oliver Turner, Stéphane Udry, Simon R. Walker, Richard G. West, Peter J. Wheatley. 2018-05-26. NGTS-2b: An inflated hot-Jupiter transiting a bright F-dwarf. https://doi.org/10.1093/mnras%2Fsty2581

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