HATS-7b: A Hot Super Neptune Transiting a Quiet K Dwarf Star
We report the discovery by the HATSouth network of HATS-7b, a transiting Super-Neptune with a mass of 0.120 ± 0.012 M_J, a radius of 0.563_(-0.034)^(+0.046) R_J, and an orbital period of 3.1853 days. The host star is a moderately bright (V = 13.340 ± 0.010 mag, K_S = 10.976 ± 0.026 mag) K dwarf star...
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American Astronomical Society
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ftcaltechauth:oai:authors.library.caltech.edu:78357 2023-05-15T16:39:21+02:00 HATS-7b: A Hot Super Neptune Transiting a Quiet K Dwarf Star Bakos, G. Á. Howard, A. W. Fulton, B. J. 2015-11-10 application/pdf https://authors.library.caltech.edu/78357/ https://authors.library.caltech.edu/78357/1/Bakos_2015_ApJ_813_111.pdf https://authors.library.caltech.edu/78357/2/1507.01024.pdf https://resolver.caltech.edu/CaltechAUTHORS:20170620-080018077 en eng American Astronomical Society https://authors.library.caltech.edu/78357/1/Bakos_2015_ApJ_813_111.pdf https://authors.library.caltech.edu/78357/2/1507.01024.pdf Bakos, G. Á. and Howard, A. W. and Fulton, B. J. (2015) HATS-7b: A Hot Super Neptune Transiting a Quiet K Dwarf Star. Astrophysical Journal, 813 (2). Art. No. 111. ISSN 0004-637X. doi:10.1088/0004-637X/813/2/111. https://resolver.caltech.edu/CaltechAUTHORS:20170620-080018077 <https://resolver.caltech.edu/CaltechAUTHORS:20170620-080018077> other Article PeerReviewed 2015 ftcaltechauth https://doi.org/10.1088/0004-637X/813/2/111 2021-11-18T18:42:34Z We report the discovery by the HATSouth network of HATS-7b, a transiting Super-Neptune with a mass of 0.120 ± 0.012 M_J, a radius of 0.563_(-0.034)^(+0.046) R_J, and an orbital period of 3.1853 days. The host star is a moderately bright (V = 13.340 ± 0.010 mag, K_S = 10.976 ± 0.026 mag) K dwarf star with a mass of 0.849 ± 0.027 M_⊙, a radius of 0.815_(-0.035)^(+0.049) R_⊙, and a metallicity of [Fe/H] = + 0.250 ± 0.080. The star is photometrically quiet to within the precision of the HATSouth measurements, has low RV jitter, and shows no evidence for chromospheric activity in its spectrum. HATS-7b is the second smallest radius planet discovered by a wide-field ground-based transit survey, and one of only a handful of Neptune-size planets with mass and radius determined to 10% precision. Theoretical modeling of HATS-7b yields a hydrogen–helium fraction of 18 ± 4% (rock-iron core and H_2–He envelope), or 9 ± 4% (ice core and H_2–He envelope), i.e., it has a composition broadly similar to that of Uranus and Neptune, and very different from that of Saturn, which has 75% of its mass in H_2–He. Based on a sample of transiting exoplanets with accurately (<20%) determined parameters, we establish approximate power-law relations for the envelopes of the mass–density distribution of exoplanets. HATS-7b, which, together with the recently discovered HATS-8b, is one of the first two transiting super-Neptunes discovered in the Southern sky, is a prime target for additional follow-up observations with Southern hemisphere facilities to characterize the atmospheres of Super-Neptunes (which we define as objects with mass greater than that of Neptune, and smaller than halfway between that of Neptune and Saturn, i.e., 0.054 M_J < M_p < 0.18 M_J). Article in Journal/Newspaper ice core Caltech Authors (California Institute of Technology) The Astrophysical Journal 813 2 111 |
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English |
description |
We report the discovery by the HATSouth network of HATS-7b, a transiting Super-Neptune with a mass of 0.120 ± 0.012 M_J, a radius of 0.563_(-0.034)^(+0.046) R_J, and an orbital period of 3.1853 days. The host star is a moderately bright (V = 13.340 ± 0.010 mag, K_S = 10.976 ± 0.026 mag) K dwarf star with a mass of 0.849 ± 0.027 M_⊙, a radius of 0.815_(-0.035)^(+0.049) R_⊙, and a metallicity of [Fe/H] = + 0.250 ± 0.080. The star is photometrically quiet to within the precision of the HATSouth measurements, has low RV jitter, and shows no evidence for chromospheric activity in its spectrum. HATS-7b is the second smallest radius planet discovered by a wide-field ground-based transit survey, and one of only a handful of Neptune-size planets with mass and radius determined to 10% precision. Theoretical modeling of HATS-7b yields a hydrogen–helium fraction of 18 ± 4% (rock-iron core and H_2–He envelope), or 9 ± 4% (ice core and H_2–He envelope), i.e., it has a composition broadly similar to that of Uranus and Neptune, and very different from that of Saturn, which has 75% of its mass in H_2–He. Based on a sample of transiting exoplanets with accurately (<20%) determined parameters, we establish approximate power-law relations for the envelopes of the mass–density distribution of exoplanets. HATS-7b, which, together with the recently discovered HATS-8b, is one of the first two transiting super-Neptunes discovered in the Southern sky, is a prime target for additional follow-up observations with Southern hemisphere facilities to characterize the atmospheres of Super-Neptunes (which we define as objects with mass greater than that of Neptune, and smaller than halfway between that of Neptune and Saturn, i.e., 0.054 M_J < M_p < 0.18 M_J). |
format |
Article in Journal/Newspaper |
author |
Bakos, G. Á. Howard, A. W. Fulton, B. J. |
spellingShingle |
Bakos, G. Á. Howard, A. W. Fulton, B. J. HATS-7b: A Hot Super Neptune Transiting a Quiet K Dwarf Star |
author_facet |
Bakos, G. Á. Howard, A. W. Fulton, B. J. |
author_sort |
Bakos, G. Á. |
title |
HATS-7b: A Hot Super Neptune Transiting a Quiet K Dwarf Star |
title_short |
HATS-7b: A Hot Super Neptune Transiting a Quiet K Dwarf Star |
title_full |
HATS-7b: A Hot Super Neptune Transiting a Quiet K Dwarf Star |
title_fullStr |
HATS-7b: A Hot Super Neptune Transiting a Quiet K Dwarf Star |
title_full_unstemmed |
HATS-7b: A Hot Super Neptune Transiting a Quiet K Dwarf Star |
title_sort |
hats-7b: a hot super neptune transiting a quiet k dwarf star |
publisher |
American Astronomical Society |
publishDate |
2015 |
url |
https://authors.library.caltech.edu/78357/ https://authors.library.caltech.edu/78357/1/Bakos_2015_ApJ_813_111.pdf https://authors.library.caltech.edu/78357/2/1507.01024.pdf https://resolver.caltech.edu/CaltechAUTHORS:20170620-080018077 |
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ice core |
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ice core |
op_relation |
https://authors.library.caltech.edu/78357/1/Bakos_2015_ApJ_813_111.pdf https://authors.library.caltech.edu/78357/2/1507.01024.pdf Bakos, G. Á. and Howard, A. W. and Fulton, B. J. (2015) HATS-7b: A Hot Super Neptune Transiting a Quiet K Dwarf Star. Astrophysical Journal, 813 (2). Art. No. 111. ISSN 0004-637X. doi:10.1088/0004-637X/813/2/111. https://resolver.caltech.edu/CaltechAUTHORS:20170620-080018077 <https://resolver.caltech.edu/CaltechAUTHORS:20170620-080018077> |
op_rights |
other |
op_doi |
https://doi.org/10.1088/0004-637X/813/2/111 |
container_title |
The Astrophysical Journal |
container_volume |
813 |
container_issue |
2 |
container_start_page |
111 |
_version_ |
1766029679266889728 |