HD 4203

View previous topic View next topic Go down

HD 4203

Post by Edasich on 9th January 2014, 4:26 am

I'm posting this eprint here because of some new data concerning exoplanet host star HD 4203 (a G dwarf) and evidence of an additional planet. Free to move this post elsewhere.

Limits on Stellar Companions to Exoplanet Host Stars With Eccentric Planets

Though there are now many hundreds of confirmed exoplanets known, the binarity of exoplanet host stars is not well understood. This is particularly true of host stars which harbor a giant planet in a highly eccentric orbit since these are more likely to have had a dramatic dynamical history which transferred angular momentum to the planet. Here we present observations of four exoplanet host stars which utilize the excellent resolving power of the Differential Speckle Survey Instrument (DSSI) on the Gemini North telescope. Two of the stars are giants and two are dwarfs. Each star is host to a giant planet with an orbital eccentricity > 0.5 and whose radial velocity data contain a trend in the residuals to the Keplerian orbit fit. These observations rule out stellar companions 4-8 magnitudes fainter than the host star at passbands of 692nm and 880nm. The resolution and field-of-view of the instrument result in exclusion radii of 0.05-1.4 arcsecs which excludes stellar companions within several AU of the host star in most cases. We further provide new radial velocities for the HD 4203 system which confirm that the linear trend previously observed in the residuals is due to an additional planet. These results place dynamical constraints on the source of the planet's eccentricities, constraints on additional planetary companions, and informs the known distribution of multiplicity amongst exoplanet host stars.

Emphasis mine.
avatar
Edasich
dM star
dM star

Number of posts : 1530
Location : Tau Ceti g - Mid Latitudes
Registration date : 2008-06-02

View user profile

Back to top Go down

Re: HD 4203

Post by Lazarus on 9th January 2014, 1:02 pm

Also it seems that the RV trend in HD 168443 is due to a third planet rather than a stellar companion.
avatar
Lazarus
dG star
dG star

Number of posts : 2894
Registration date : 2008-06-12

View user profile

Back to top Go down

Re: HD 4203

Post by Edasich on 11th January 2014, 11:57 am

avatar
Edasich
dM star
dM star

Number of posts : 1530
Location : Tau Ceti g - Mid Latitudes
Registration date : 2008-06-02

View user profile

Back to top Go down

Re: HD 4203

Post by Sponsored content


Sponsored content


Back to top Go down

View previous topic View next topic Back to top


 
Permissions in this forum:
You cannot reply to topics in this forum