Astronomy and Astrophysics – Astrophysics
Scientific paper
2006-06-27
Astrophys.J.651:1177-1193,2006
Astronomy and Astrophysics
Astrophysics
accepted for publication in The Astrophysical Journal
Scientific paper
10.1086/507761
We have carried out a sensitive search for gas emission lines at infrared and millimeter wavelengths for a sample of 15 young sun-like stars selected from our dust disk survey with the Spitzer Space Telescope. We have used mid-infrared lines to trace the warm (300-100 K) gas in the inner disk and millimeter transitions of 12CO to probe the cold (~20 K) outer disk. We report no gas line detections from our sample. Line flux upper limits are first converted to warm and cold gas mass limits using simple approximations allowing a direct comparison with values from the literature. We also present results from more sophisticated models following Gorti and Hollenbach (2004) which confirm and extend our simple analysis. These models show that the SI line at 25.23 micron can set constraining limits on the gas surface density at the disk inner radius and traces disk regions up to a few AU. We find that none of the 15 systems have more than 0.04 MJ of gas within a few AU from the disk inner radius for disk radii from 1 AU up to ~40 AU. These gas mass upper limits even in the 8 systems younger than ~30 Myr suggest that most of the gas is dispersed early. The gas mass upper limits in the 10-40 AU region, that is mainly traced by our CO data, are <2 Mearth. If these systems are analogs of the Solar System, either they have already formed Uranus- and Neptune-like planets or they will not form them beyond 100 Myr. Finally, the gas surface density upper limits at 1 AU are smaller than 0.01% of the minimum mass solar nebula for most of the sources. If terrestrial planets form frequently and their orbits are circularized by gas, then circularization occurs early.
Bouwman Jeroen
Carpenter John Michael
Gorti Uma
Herczeg Gregory J.
Hillenbrand Lynne A.
No associations
LandOfFree
Formation and Evolution of Planetary Systems: Upper Limits to the Gas Mass in Disks Around Sun-like Stars 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 Formation and Evolution of Planetary Systems: Upper Limits to the Gas Mass in Disks Around Sun-like Stars, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Formation and Evolution of Planetary Systems: Upper Limits to the Gas Mass in Disks Around Sun-like Stars will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-534641