2012ApJ...744..116B -
Astrophys. J., 744, 116 (2012/January-2)
A 30 AU radius CO gas hole in the disk around the Herbig Ae star Oph IRS 48.
BROWN J.M., HERCZEG G.J., PONTOPPIDAN K.M. and VAN DISHOECK E.F.
Abstract (from CDS):
The physical processes leading to the disappearance of disks around young stars are not well understood. A subclass of transitional disks, the so-called cold disks with large inner dust holes, provides a crucial laboratory for studying disk dissipation processes. IRS 48 has a 30 AU radius hole previously measured from dust continuum imaging at 18.7 µm. Using new optical spectra, we determine that IRS 48 is a pre-main-sequence A0 star. In order to characterize this disk's gas distribution, we obtained AO-assisted Very Large Telescope CRIRES high-resolution (R ∼ 100,000) spectra of the CO fundamental rovibrational band at 4.7 µm. All CO emission, including that from isotopologues and vibrationally excited molecules, is off-source and peaks at 30 AU. The gas is thermally excited to a rotational temperature of 260 K and is also strongly UV pumped, showing a vibrational excitation temperature of ∼5000 K. We model the kinematics and excitation of the gas and posit that the CO emission arises from the dust hole wall. Prior imaging of UV-excited polycyclic aromatic hydrocarbon molecules, usually a gas tracer, within the hole makes the large CO hole even more unexpected.
Abstract Copyright:
∼
Journal keyword(s):
planetary systems - protoplanetary disks - stars: individual: Oph IRS 48 - stars: pre-main sequence
Simbad objects:
13
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2012ApJ...744..116B and select 'bookmark this link' or equivalent in the popup menu