NGTS-2b: an inflated hot-Jupiter transiting a bright F-dwarf. Issue 4 (20th September 2018)

• Record Type: Journal Article
• Authors: Raynard, Liam; Goad, Michael R; Gillen, Edward; Nielsen, Louise D; Watson, Christopher A; Thompson, Andrew P G; McCormac, James; Bayliss, Daniel; Soto, Maritza; Csizmadia, Szilard; Chaushev, Alexander; Burleigh, Matthew R; Alexander, Richard; Armstrong, David J; Bouchy, François; Briegal, Joshua T; Cabrera, Juan; Casewell, Sarah L; Chazelas, Bruno; Cooke, Benjamin F; Eigmüller, Philipp; Erikson, Anders; Gänsicke, Boris T; Grange, Andrew; Günther, Maximilian N; Hodgkin, Simon T; Hooton, Matthew J; Jenkins, James S; Lambert, Gregory; Louden, Tom; Metrailler, Lionel; Moyano, Maximiliano; Pollacco, Don; Poppenhaeger, Katja; Queloz, Didier; Raddi, Roberto; Rauer, Heike; Read, Andrew M; Smalley, Barry; Smith, Alexis M S; Turner, Oliver; Udry, Stéphane; Walker, Simon R; West, Richard G; Wheatley, Peter J;
• Is Part Of: Monthly notices of the Royal Astronomical Society. Volume 481:Issue 4(2018)
• Page Start: 4960
• Page End: 4970
• Publication Date: 2018-09-20
• Subjects: planets and satellites: detection -- planets and satellites: fundamental parameters; Astronomy -- Periodicals; Periodicals; 520.5
• DOI: 10.1093/mnras/sty2581
• Languages: English
• ISSNs: 0035-8711

Abstract

Abstract: We report the discovery of NGTS-2b, an inflated hot-Jupiter transiting a bright F5V star (2MASS J14202949 − 3112074; T eff = $6478^{+94}_{-89}$ K), discovered as part of the Next Generation Transit Survey ( NGTS ). The planet is in a P = 4.51 d 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 $1.0{{\ \rm per\ cent}}$ 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 ($v$ sin i = 15.2 ± 0.8 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.