J/MNRAS/484/3731 GJ 9827 HARPS-N RV data (Rice+, 2019)
Masses and radii for the three super-Earths orbiting GJ 9827, and implications
for the composition of small exoplanets.
Rice K., Malavolta L., Mayo A., Mortier A., Buchhave L.A., Affer L.,
Vanderburg A., Lopez-Morales M., Poretti E., Zeng L., Cameron A.C.,
Damasso M., Coffinet A., Latham D.W., Bonomo A.S., Bouchy F.,
Charbonneau D., Dumusque X., Figueira P., Martinez Fiorenzano A.F.,
Haywood R.D., Johnson J.A., Lopez E., Lovis C., Mayor M., Micela G.,
Molinari E., Nascimbeni V., Nava C., Pepe F., Phillips D.F., Piotto G.,
Sasselov D., Segransan D., Sozzetti A., Udry S., Watson C.
<Mon. Not. R. Astron. Soc., 484, 3731-3745 (2019)>
=2019MNRAS.484.3731R 2019MNRAS.484.3731R (SIMBAD/NED BibCode)
ADC_Keywords: Stars, double and multiple ; Stars, K-type ; Exoplanets ;
Radial velocities
Keywords: techniques: radial velocities - planets and satellites: composition -
planets and satellites: detection -
planets and satellites: fundamental parameters -
planets and satellites: general - stars: individual: GJ 9827
Abstract:
Super-Earths belong to a class of planet not found in the Solar
system, but which appear common in the Galaxy. Given that some
super-Earths are rocky, while others retain substantial atmospheres,
their study can provide clues as to the formation of both rocky and
gaseous planets, and - in particular - they can help to constrain
the role of photoevaporation in sculpting the exoplanet population.
GJ 9827 is a system already known to host three super-Earths with
orbital periods of 1.2, 3.6, and 6.2d. Here, we use new HARPS-N radial
velocity measurements, together with previously published radial
velocities, to better constrain the properties of the GJ 9827 planets.
Our analysis cannot place a strong constraint on the mass of
GJ 9827 c, but does indicate that GJ 9827 b is rocky with a
composition that is probably similar to that of the Earth, while
GJ 9827 d almost certainly retains a volatile envelope. Therefore,
GJ 9827 hosts planets on either side of the radius gap that appears to
divide super-Earths into pre-dominantly rocky ones that have radii
below ∼1.5R⊕, and ones that still retain a substantial
atmosphere and/or volatile components, and have radii above
∼2R⊕. That the less heavily irradiated of the three planets
still retains an atmosphere, may indicate that photoevaporation has
played a key role in the evolution of the planets in this system.
Description:
tablea1.dat contains the radial velocities and activity indicators for
GJ 9827 obtained by HARPS-N.
Objects:
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RA (2000) DE Designation(s)
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23 27 04.84 -01 17 10.6 GJ 9827 = EPIC 246389858
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 60 41 HARPS-N RV data
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Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 14 F14.6 d BJD Barycentric Julian Day
16- 23 F8.2 m/s RV Radial Velocity
25- 28 F4.2 m/s e_RV Error in radial velocity
30- 34 F5.2 m/s BIS Bisector Inverse Span
36- 42 F7.5 km/s FWHM Full-width-at-half-maximum of the CCF
44- 51 F8.6 --- SMW Mount Wilson S-index
53- 60 F8.6 --- e_SMW Mount wilson S-index error
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Acknowledgements:
Ken Rice, wkmr(at)roe.ac.uk
(End) Patricia Vannier [CDS] 08-Feb-2021