Constraints on the Circumstellar Disk Masses in the IC 348 Cluster

A 5.2' x 5.2' region toward the young cluster IC 348 has been imaged in themillimeter continuum at 4.0" x 4.9" resolution with the OVRO interferometer toa RMS noise level of 0.75 mJy/beam at 98 GHz. The data are used to constrainthe circumstellar disk masses in a cluster environment at an age of about 2Myr. The mosaic encompasses 95 known members of the IC 348 cluster with astellar mass distribution that peaks at 0.2-0.5 Msun. None of the stars aredetected in the millimeter continuum at an intensity level of 3 sigma orgreater. The mean observed flux for the ensemble of 95 stars is 0.22 +/- 0.08mJy. Assuming a dust temperature of 20 K, a mass opacity coefficient of kappa_o= 0.02 cm^2/g at 1300 um, and a power law index of beta=1 for the particleemissivity, these observations imply that the 3 sigma upper limit to the diskmass around any individual star is 0.025 Msun, and that the average disk massis 0.002 +/- 0.001 Msun. The absence of disks with masses in excess of 0.025Msun in IC 348 is different at the about 3 sigma confidence level from Taurus,where about 14% of the stars in an optically selected sample have such diskmasses. Compared with the minimum mass needed to form the planets in our solarsystem (about 0.01 Msun), the lack of massive disks and the low mean disk massin IC 348 suggest either that planets more massive than a few Jupiter masseswill form infrequently around 0.2-0.5 Msun stars in IC 348, or that the processto form such planets has significantly depleted the disk of small dust grainson time scales less than the cluster age of about 2 Myr.Comment: accepted by A