Planets at UZ For?

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Planets at UZ For?

Post by Sirius_Alpha on 7th June 2011, 9:10 pm

Possible detection of two giant extrasolar planets orbiting the eclipsing polar UZ Fornacis
http://arxiv.org/abs/1106.1404

We present new high-speed, multi-observatory, multi-instrument photometry of the eclipsing polar UZ For in order to measure precise mid-eclipse times with the aim of detecting any orbital period variations. When combined with published eclipse times and archival data spanning ~27 years, we detect departures from a linear and quadratic trend of ~60 s. The departures are strongly suggestive of two cyclic variations of 16(3) and 5.25(25) years. The two favoured mechanisms to drive the periodicities are either two giant extrasolar planets as companions to the binary (with minimum masses of 6.3(1.5)M(Jupiter) and 7.7(1.2)M(Jupiter)) or a magnetic cycle mechanism (e.g. Applegate's mechanism) of the secondary star. Applegate's mechanism would require the entire radiant energy output of the secondary and would therefore seem to be the least likely of the two, barring any further refinements in the effect of magnetic fieilds (e.g. those of Lanza et al.). The two planet model can provide realistic solutions but it does not quite capture all of the eclipse times measurements. A highly eccentric orbit for the outer planet would fit the data nicely, but we find that such a solution would be unstable. It is also possible that the periodicities are driven by some combination of both mechanisms. Further observations of this system are encouraged.

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Re: Planets at UZ For?

Post by Lazarus on 29th January 2014, 2:16 am

Wobbling Ancient Binaries - Here Be Planets?
http://arxiv.org/abs/1401.6742

Looks like along with NN Serpentis, this orbital configuration is long-term stable. Looks like it will be the next one to go through a determination of whether the planets can be primordial planets that survived the common-envelope stage or not.
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Re: Planets at UZ For?

Post by Edasich on 30th January 2014, 9:50 am

Lazarus wrote: Wobbling Ancient Binaries - Here Be Planets?
http://arxiv.org/abs/1401.6742

Looks like along with NN Serpentis, this orbital configuration is long-term stable. Looks like it will be the next one to go through a determination of whether the planets can be primordial planets that survived the common-envelope stage or not.

Would this also imply that second planet candidate "UZ Fornacis c" is confirmed?  Question
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Re: Planets at UZ For?

Post by Edasich on 31st January 2014, 5:31 am

Self-answer. NASA Exoplanet archive lists it as "confirmed":

http://exoplanetarchive.ipac.caltech.edu/cgi-bin/DisplayOverview/nph-DisplayOverview?objname=UZ+For+c&type=CONFIRMED_PLANET
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