New Stellar Companions to Exoplanet Hosts

Binary frequency of planet-host stars at wide separations: A new brown dwarf companion to a planet-host star
http://arxiv.org/abs/1408.1208

You're kinda very blatantly missing the other discoveries, y'know. Update that title!

In other news…

Quote :

We note that only one system, not included in the plots shown by Mugrauer et al. (2007a), has a short period (<40 days) and an eccentricity higher than 0.05, the possible planet "e" around 55 Cnc A (Wisdom 2005) which remains to be confirmed.

…I seem to have developed an urge to punch something.

Good point, I misread the abstract before reading through the paper.

Quote :

In other news…

Well, it has a pretty short period. I wonder if we can confirm it with a transit search?   

Tried to read this as charitably as possible by assuming they meant the eccentricity value is not concerned, but no, they cite Wisdom 2005, call the planet "possible" and in any case the orbital fits since the transit detection generally come out with very low eccentricity values.

I was also interested to see HD 217107 listed as a ~10 AU binary. There IS in fact a listing in the WDS for such a companion, but as noted by Desidera & Barbieri (2007), no evidence was found for this in the planet searches, and would be dynamically inconsistent with the existence of the outer planet. From what I can tell, the arguments given there against the identification of the purported binary companion with the outer RV planet candidate (i.e. the possibility that it is a near-face-on binary) are still applicable to the Wright et al. (2009) orbital solution, at least the given periastron time happens close to the latest WDS observation.

Also, technically only the brown dwarf is new: the wide companion to HD 126614 and the binarity of HD 213240 were already known.

There are a good few new wide companion candidates, is just that they're so wide that the writers aren't sure if they're physically bound. Given the unlikelihood of similar proper motions, I'd say a fair few of those have some level of relationship.