Thursday, October 27, 2005

Random Snippets from PPV: Part II


Wittenmeyer et al have taken 20 years of McDonald data plus some data from the pioneering Campbell & Walker radial velocity survey (1988) to constrain high mass giant planets in long period orbits.
Conclusion is that within their sensitivity limit (~ 3 M_Jupiter at ~ 5 AU) less than 20% of their stars (+- 5 %) have such massive long period planets.

Galland et al show the radial velocity surveys can be done on F and A stars. And find a ~ 10 M_Jupiter object at ~ 1 AU around an F6V star.

About 1% of stars in searched samples have "hot jupiters"

About 10% (formally 7%) of stars have "warm eccentric jupiters"

About 20% of stars appear to have no giant planets out to quite large semi-major axis.

It is possible that 50-70% of stars (K and G main sequence stars) have planetary systems similar to the Solar Systems.
Preliminary indications are that >> 10% do, based on incomplete data and trends (this is my personal interpretation of unpublished data others have taken, not a scientific analysis; a very conservative extrapolation at this meeting claimed minumum 12-15%).

M stars being surveyed at high precision are now showing velocity trends and we can expect a lot of planets around M stars. This will confound formation theories at a nuisance level. Possibly major nuisance. I still think the basic theory is right, but a lot of detail is missing.

Hyades survey found no short orbital periods jovians around a sample of 100 metal rich stars.

Boss reports that Hatzes et al (2005) have 10 detections of long period jovians around metal poor K giants.
I can not find the preprint, yet.

There will be a lot of G and K giant stars with planets found around them, probing the intermediate mass and old solar mass population, soon.

There are now 7 known planets, detected through optical radial velocity surveys, with masses less than 20 Earth masses.
This number will increase very rapidly over the next couple of years.

This is getting to be really interesting.


Blogger Adam Solomon said...

Getting to be really interesting indeed! Wish I could be (could have been?) there.

12:15 AM  

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