{"about":{"site":"https://codewithpapers.app","non_affiliation":"Code with Papers and Syntology are not affiliated with, endorsed by, or sponsored by Papers with Code, Meta, or the pwc-archive mirror.","licence":"CC BY-SA 4.0","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","attribution":"https://codewithpapers.app/attribution","modified":"archive material modified by Syntology; see the attribution page"},"url":"/paper/k2-139-b-a-low-mass-warm-jupiter-on-a-29-day","title":"K2-139 b: a low-mass warm Jupiter on a 29-day orbit transiting an active K0 V star","arxiv_id":"1702.00691","date":"2017-02-02","proceeding":null,"authors":["O. Barragán","D. Gandolfi","A. M. S. Smith","H. J. Deeg","M. C. V. Fridlund","C. M. Persson","P. Donati","M. Endl","Sz. Csizmadia","S. Grziwa","D. Nespral","A. P. Hatzes","W. D. Cochran","L. Fossati","S. S. Brems","J. Cabrera","F. Cusano","Ph. Eigmüller","C. Eiroa","A. Erikson","E. Guenther","J. Korth","D. Lorenzo-Oliveira","L. Mancini","M. Pätzold","J. Prieto-Arranz","H. Rauer","I. Rebollido","J. Saario","O. V. Zakhozhay"],"abstract":"We announce the discovery of K2-139 b (EPIC 218916923 b), a transiting warm-Jupiter ($T_\\mathrm{eq}$=547$\\pm$25 K) on a 29-day orbit around an active (log $R^\\prime_\\mathrm{HK}$ = $-$4.46 $\\pm$ 0.06) K0 V star in K2 Campaign 7. We derive the system's parameters by combining the K2 photometry with ground-based follow-up observations. With a mass of~$0.387 _{ - 0.075 } ^ {+ 0.083 } M_{\\rm J}$ and radius of $0.808 _{ - 0.033 } ^ {+ 0.034 } R_{\\rm J}$, K2-139 b is one of the transiting warm Jupiters with the lowest mass known to date. The planetary mean density of $0.91 _{ - 0.20} ^ { + 0.24 }$ $\\mathrm{g cm^{-3}}$ can be explained with a core of $\\sim$50 $M_\\oplus$. Given the brightness of the host star ($V$ = 11.653 mag), the relatively short transit duration ($\\sim$5 hours), and the expected amplitude of the Rossiter-McLaughlin effect ($\\sim25 {\\rm m s^{-1}}$ ), K2-139 is an ideal target to measure the spin-orbit angle of a planetary system hosting a warm Jupiter.","url_abs":"http://arxiv.org/abs/1702.00691v2","url_pdf":"http://arxiv.org/pdf/1702.00691v2.pdf","source":{"archive":"pwc-archive (Hugging Face), CC BY-SA 4.0","snapshot":"2025-07-28","licence_url":"https://creativecommons.org/licenses/by-sa/4.0/legalcode","row_kind":"links_only","authors_date_abstract":"arXiv metadata, CC0 1.0 (https://info.arxiv.org/help/license), from the Kaggle arXiv metadata snapshot of 2026-09-12"},"code_links":[{"paper_slug":"k2-139-b-a-low-mass-warm-jupiter-on-a-29-day","repo_url":"https://github.com/oscaribv/exotrending","is_official":1,"mentioned_in_paper":1,"mentioned_in_github":1,"framework":"none","reach":null}],"tasks":[],"methods":[],"datasets_introduced":[],"methods_introduced":[],"results":[],"syntology":{"syntology_url":null,"atlas_url":null,"mcp":null,"developers":"https://syntology.ai/developers"},"arxiv_metadata":null,"syntology_extracted_results":null}