Sirius_Alpha Admin
Number of posts : 4320 Location : Earth Registration date : 2008-04-06
| Subject: HARPS-N finds planets at HD 238914 and TYC 3318-01333-1 (and others) 15th January 2018, 9:38 pm | |
| Tracking Advanced Planetary Systems (TAPAS) with HARPS-N. VI. HD 238914 and TYC 3318-01333-1 - two more Li-rich giants with planets https://arxiv.org/abs/1801.04379 - Quote :
- We present the latest results of our search for planets with HARPS-N at the 3.6 m Telescopio Nazionale Galileo under the Tracking Advanced Planetary Systems project: an in-depth study of the 15 most Li abundant giants from the PennState - Toru\'n Planet Search sample. Our goals are first, to obtain radial velocities of the most Li-rich giants we identified in our sample to search for possible low-mass substellar companions, and second, to perform an extended spectral analysis to define the evolutionary status of these stars. Methods. This work is based on high-resolution spectra obtained with the Hobby-Eberly Telescope and its High Resolution Spectro- graph, and with the HARPS-N spectrograph at the Telescopio Nazionale Galileo. Two stars, HD 181368 and HD 188214 , were also observed with UVES at the VLT to determine beryllium abundances. We report i) the discovery of two new planetary systems around the Li-rich giant stars: HD 238914 and TYC 3318-01333- 1 (a binary system); ii) reveal a binary Li-rich giant, HD 181368 ; iii) although our current phase coverage is not complete, we suggest the presence of planetary mass companions around TYC 3663-01966-1 and TYC 3105-00152-1 ; iv) we confirm the previous result for BD+48 740 and present updated orbital parameters, and v) we find a lack of a relation between the Li enhancement and the Be abundance for the stars HD 181368 and HD 188214 , for which we acquired blue spectra. We found seven stars with stellar or potential planetary companions among the 15 Li-rich giant stars. The binary star frequency of the Li-rich giants in our sample appears to be normal, but the planet frequency is twice that of the general sample, which suggests a possible connection between hosting a companion and enhanced Li abundance in giant stars. We also found most of the companions orbits to be highly eccentric.
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Last edited by Sirius_Alpha on 16th January 2018, 5:54 pm; edited 1 time in total | |
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Sirius_Alpha Admin
Number of posts : 4320 Location : Earth Registration date : 2008-04-06
| Subject: Re: HARPS-N finds planets at HD 238914 and TYC 3318-01333-1 (and others) 16th January 2018, 5:38 pm | |
| Reading through the paper, there's quite a few more planets in there than I thought. None of these planets I had in my notes, with the exception of BD+48 740 b as previously unconfirmed.
BD+48 740 Ab, HD 238914 Ab, TYC 3318-1333-1 Ab, TYC 3663-1966 Ab, TYC 3105-152-1 Ab _________________ Caps Lock: Cruise control for 'Cool'!
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