The Frequency of Low-Mass Exoplanets. III. Toward eta-Earth at Short Periods

Details The Frequency of Low-Mass Exoplanets. III. Toward eta-Earth at Short Periods The Frequency of Low-Mass Exoplanets. III. Toward eta-Earth at Short Periods

2011-03-22

arxiv.org/abs/1103.4186v1

Astronomy and Astrophysics

Astrophysics

Earth and Planetary Astrophysics

Submitted to ApJ, 2011 March 16

Scientific paper

Determining the occurrence rate of terrestrial-mass planets (m_p < 10M_earth) is a critically important step on the path towards determining the frequency of Earth-like planets (eta-Earth), and hence the uniqueness of our Solar system. Current radial-velocity surveys, achieving precisions of 1 m/s, are able to detect terrestrial-mass planets and provide meaningful estimates of their occurrence rate. We present an analysis of 67 solar-type stars from the Anglo-Australian Planet Search specifically targeted for very high-precision observations. When corrected for incompleteness, we find that the planet occurrence rate increases sharply with decreasing planetary mass. Our results are consistent with those from other surveys: in periods shorter than 50 days, we find that 1.5% of stars host a giant (m_p > 100M_earth) planet, and that 18.5% of stars host a planet with m_p < 10M_earth. The preponderance of low-mass planets in short-period orbits is in conflict with formation simulations in which the majority of terrestrial-mass planets reside at larger orbital distances. This work gives a hint as to the size of eta-Earth, but to make meaningful predictions on the frequency of terrestrial planets in longer, potentially habitable orbits, low-mass terrestrial planet searches at periods of 100-200 days must be made an urgent priority for ground-based Doppler planet searches in the years ahead.

Affiliated with

Also associated with

No associations

Rating

The Frequency of Low-Mass Exoplanets. III. Toward eta-Earth at Short Periods does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with The Frequency of Low-Mass Exoplanets. III. Toward eta-Earth at Short Periods, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Frequency of Low-Mass Exoplanets. III. Toward eta-Earth at Short Periods will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-48163