Related papers: A Resolved Molecular Gas Disk around the Nearby A …
We present the first scattered-light images of the debris disk around 49 ceti, a ~40 Myr A1 main sequence star at 59 pc, famous for hosting two massive dust belts as well as large quantities of atomic and molecular gas. The outer disk is…
Gas-rich primordial disks and tenuous gas-poor debris disks are usually considered as two distinct evolutionary phases of the circumstellar matter. Interestingly, the debris disk around the young main-sequence star 49 Ceti possesses a…
We present far-IR/sub-mm imaging and spectroscopy of 49 Ceti, an unusual circumstellar disk around a nearby young A1V star. The system is famous for showing the dust properties of a debris disk, but the gas properties of a low-mass…
We present ~0.4 resolution images of CO(3-2) and associated continuum emission from the gas-bearing debris disk around the nearby A star 49 Ceti, observed with the Atacama Large Millimeter/Submillimeter Array (ALMA). We analyze the ALMA…
We present analysis of time-variable, shifted absorption features in far-UV spectra of the unusual 49 Ceti debris disk. This nearly edge-on disk is one of the brightest known, and is one of the very few containing detectable amounts of…
We present Hubble Space Telescope STIS far-UV spectra of the edge-on disk around 49 Ceti, one of the very few debris disks showing sub-mm CO emission. Many atomic absorption lines are present in the spectra, most of which arise from…
Sub-arcsecond scale Keck images of the young A1V star, 49 Ceti, resolve emission at lambda = 12.5 and 17.9 microns from a disk with long axis at PA 125 pm 10 degrees and inclination phi = 60 pm 15 degrees . At 17.9 microns, the emission is…
Surprisingly strong CO emission has been observed from more than a dozen debris disks around nearby main-sequence stars. The origin of this CO is unclear, in particular whether it is left over from the protoplanetary disk phase or is…
We present the first sub-arcsecond images of 49 Ceti in the [C I]3P1-3P0 emission and the 614 micron dust continuum emission observed with ALMA, as well as that in the CO(J=3-2) emission prepared by using the ALMA archival data. The spatial…
We present high resolution ALMA observations of the CO(3-2) and 350 GHz continuum emissions of the debris disc of 49 Ceti, known to be particularly rich in molecular gas in spite of its age. The main new results are: i) both CO and dust…
The gaseous molecular disk that orbits the main sequence A-type star 49 Ceti has been known since 1995, but the stellar age and the origin of the observed carbon monoxide molecules have been unknown. We now identify 49 Ceti as a member of…
Characterization of gas component in debris disks is of fundamental importance for understanding its origin. Toward this goal, we have conducted non-LTE (local thermodynamic equilibrium) analyses of the rotational spectral lines of CO…
We measured 304 absorption features in the ultraviolet and visible spectra of the star 51 Oph, which is known to have a debris disk with a high inclination. We analyzed the relative populations of atoms in excited fine-structure and…
In a multi-wavelength study of thermal emission and scattered light images we analyse the dust properties and structure of the debris disc around the A1-type main sequence star 49~Cet. As a basis for this study, we present new scattered…
Previous molecular gas observations at arcsecond-scale resolution of the Seyfert 2 galaxy M51 suggest the presence of a dense circumnuclear rotating disk, which may be the reservoir for fueling the active nucleus and obscures it from direct…
94 Ceti is a triple star system with a circumprimary gas giant planet and far-infrared excess. Such excesses around main sequence stars are likely due to debris discs, and are considered as signposts of planetary systems and, therefore,…
According to the current paradigm of circumstellar disk evolution, gas-rich primordial disks evolve into gas-poor debris disks compose of second-generation dust. To explore the transition between these phases, we searched for $^{12}$CO,…
We investigate the physical structure of the gas component of the disk around the pre-main-sequence star HD169142. The 13CO and C18O J=2-1 line emission is observed from the disk with 1.4'' resolution using the Submillimeter Array. We adopt…
We have detected [C I] 3P1-3P0 emissions in the gaseous debris disks of 49 Ceti and Beta Pictoris with the 10 m telescope of the Atacama Submillimeter Telescope Experiment, which is the first detection of such emissions. The line profiles…
Previous observations revealed the existence of CO gas at nearly protoplanetary level in several dust-rich debris disks around young A-type stars. Here we used the ALMA 7m-array to measure $^{13}$CO and C$^{18}$O emission toward two debris…