TY - JOUR
T1 - K2-161b
T2 - A low-density super-neptune on an eccentric orbit
AU - Brahm, R.
AU - Espinoza, N.
AU - Rabus, M.
AU - Jordán, A.
AU - Díaz, M. R.
AU - Rojas, F.
AU - Vučković, M.
AU - Zapata, A.
AU - Cortés, C.
AU - Drass, H.
AU - Jenkins, J. S.
AU - Lachaume, R.
AU - Pantoja, B.
AU - Sarkis, P.
AU - Soto, M. G.
AU - Vasquez, S.
AU - Henning, Th
AU - Jones, M. I.
N1 - Funding Information:
RB acknowledges support from FONDECYT Post-doctoral Fellowship Project No. 3180246. AJ acknowledges support from FONDECYT project 1171208, BASAL CATA PFB-06, and project IC120009 ‘Millennium Institute of Astrophysics (MAS)’ of the Millennium Science Initiative, Chilean Ministry of Economy. AZ acknowledges support by CONICYT-PFCHA/Doctorado Nacional-21170536, Chile. MRD acknowledges support by CONICYT-PFCHA/Doctorado Nacional-21140646, Chile. JSJ acknowledges support by FONDECYT project 1161218 and partial support by BASAL CATA PFB-06. Support for CC is provided by Proyecto FONDECYT Iniciación a la Investigación 11150768. This paper includes data collected by the K2 mission. Funding for the K2 mission is provided by the NASA Science Mission directorate. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https: //www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programmes 094.C-0428(A), 0101.C-0407(A), 0101.C-0497(A).
Funding Information:
RB acknowledges support from FONDECYT Post-doctoral Fellowship Project No. 3180246. AJ acknowledges support from FONDECYT project 1171208, BASAL CATA PFB-06, and project IC120009 'Millennium Institute of Astrophysics (MAS)' of the Millennium Science Initiative, Chilean Ministry of Economy. AZ acknowledges support by CONICYT-PFCHA/Doctorado Nacional-21170536, Chile. MRD acknowledges support by CONICYTPFCHA/Doctorado Nacional-21140646, Chile. JSJ acknowledges support by FONDECYT project 1161218 and partial support by BASAL CATA PFB-06. Support for CC is provided by Proyecto FONDECYT Iniciación a la Investigación 11150768. This paper includes data collected by the K2 mission. Funding for the K2 mission is provided by the NASA Science Mission directorate. This work has made use of data from the European Space Agency (ESA) mission Gaia (https://www.cosmos.esa.int/gaia), processed by the Gaia Data Processing and Analysis Consortium (DPAC, https: //www.cosmos.esa.int/web/gaia/dpac/consortium). Funding for the DPAC has been provided by national institutions, in particular the institutions participating in the Gaia Multilateral Agreement. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere under ESO programmes 094.C-0428(A), 0101.C-0407(A), 0101.C-0497(A).
Publisher Copyright:
© 2018 The Author(s).
PY - 2019/2/21
Y1 - 2019/2/21
N2 - We report the discovery of K2-161b, which was first identified as a planetary candidate from Kepler K2 photometry of Campaign 14, and whose planetary nature and orbital parameters were then confirmed with precision radial velocities. K2-161b is half as massive as Saturn (MP = 0.179 ± 0.021 MJ), and has a radius of RP = 0.840 ± 0.011 RJ, which translates into a bulk density of ρP = 0.37 ± 0.05 g cm-3. K2-161b transits its slightly evolved G-type host star (M∗ = 1.105 ± 0.019 M⊙, R∗ = 1.669 ± 0.022 R⊙) every 11.633 64 ± 0.000 10 d and presents a significantly eccentric orbit (e = 0.420 ± 0.034). We estimate a relatively short circularization time-scale of 1.8 Gyr for the planet, but given the advanced age of the system we expect the planet to be engulfed by its evolving host star in ∼1 Gyr before the orbit circularizes. The low density of the planet coupled to the brightness of the host star (J = 9.4) makes this system one of the best candidates known to date in the super-Neptune regime for atmospheric characterization via transmission spectroscopy, and to further study the transition region between ice and gas giant planets.
AB - We report the discovery of K2-161b, which was first identified as a planetary candidate from Kepler K2 photometry of Campaign 14, and whose planetary nature and orbital parameters were then confirmed with precision radial velocities. K2-161b is half as massive as Saturn (MP = 0.179 ± 0.021 MJ), and has a radius of RP = 0.840 ± 0.011 RJ, which translates into a bulk density of ρP = 0.37 ± 0.05 g cm-3. K2-161b transits its slightly evolved G-type host star (M∗ = 1.105 ± 0.019 M⊙, R∗ = 1.669 ± 0.022 R⊙) every 11.633 64 ± 0.000 10 d and presents a significantly eccentric orbit (e = 0.420 ± 0.034). We estimate a relatively short circularization time-scale of 1.8 Gyr for the planet, but given the advanced age of the system we expect the planet to be engulfed by its evolving host star in ∼1 Gyr before the orbit circularizes. The low density of the planet coupled to the brightness of the host star (J = 9.4) makes this system one of the best candidates known to date in the super-Neptune regime for atmospheric characterization via transmission spectroscopy, and to further study the transition region between ice and gas giant planets.
KW - Planets and satellites: fundamental parameters
KW - Stars: fundamental parameters
KW - Stars: individual: K2-161
KW - Techniques: photometric
KW - Techniques: radial velocities
UR - http://www.scopus.com/inward/record.url?scp=85066980377&partnerID=8YFLogxK
U2 - 10.1093/mnras/sty3230
DO - 10.1093/mnras/sty3230
M3 - Article
AN - SCOPUS:85066980377
SN - 0035-8711
VL - 483
SP - 1970
EP - 1979
JO - Monthly Notices of the Royal Astronomical Society
JF - Monthly Notices of the Royal Astronomical Society
IS - 2
ER -