Related papers: A Low-Mass H2 Component to the AU Microscopii Circ…
We report observations of molecular oxygen (O$_2$) rotational transitions at 487 GHz, 774 GHz, and 1121 GHz toward Orion Peak A. The O2 lines at 487 GHz and 774 GHz are detected at velocities of 10-12 km/s with line widths 3 km/s; however,…
In front of the LMC molecular hydrogen is found in absorption near 0 km/s, being local disk gas, near +60 km/s in an intermediate velocity cloud, and near +120 km/s, in a high velocity halo cloud. The nature of the gas is discussed based on…
Recent studies of nearby spiral galaxies suggest that photodissociation regions (PDRs) are capable of producing much of the observed HI in galaxy disks. In that case, measurements of the HI column density and the far-ultraviolet (FUV)…
[Abridged] Do some environments favor efficient conversion of molecular gas into stars? To answer this, we need to be able to estimate the H2 mass. Traditionally, this is done using CO and a few assumptions but the Herschel observations in…
We study the sub-AU-scale circumstellar environment of the Herbig Ae star HD144432 with near-infrared (NIR) VLTI/AMBER observations to investigate the structure of its inner dust disk. The interferometric observations were carried out with…
The ultraviolet and far--ultraviolet spectra of HD 147888 allows to access the v=0 as well as higher vibrational levels of the ground H2 electronic level. We have determined column densities of the H2 molecule on vibrational levels v=0-5…
We report infrared spectroscopic observations of HD 105, a nearby ($\sim 40$ pc) and relatively young ($\sim 30$ Myr) G0 star with excess infrared continuum emission, which has been modeled as arising from an optically thin circumstellar…
We model gas and dust emission from regions 0.3-20 AU from a central low mass star in intermediate-aged(~10Myr) disks with optically thin dust. The models treat thermal balance and chemistry self-consistently and calculate the vertical…
Using high-resolution (~85000) and high signal-to-noise ratio (~200) optical spectra acquired with the European Southern Observatory Ultraviolet and Visual Echelle Spectrograph, we have determined the interstellar column densities of C2 for…
Aims: The aim of this work is to study the structure of the protoplanetary disk surrounding the Herbig Ae star HD 163296. Methods: We have used high-resolution and high-sensitivity ALMA observations of the CO(3-2) emission line and the…
Studying molecular species in protoplanetary disks is very useful to characterize the properties of these objects, which are the site of planet formation. We attempt to constrain the chemistry of S-bearing molecules in the cold parts of…
We have detected H$_2$O and O$_2$ absorption against the far-UV continuum of stars located on lines of sight near the nucleus of Comet 67P/Churyumov-Gerasimenko using the Alice imaging spectrograph on Rosetta. These stellar appulses…
Mid-infrared spectroscopy of protoplanetary disks provides a chemical inventory of gas within a few au, where planets are readily detected around older stars. With the JWST Disk Infrared Spectral Chemistry Survey (JDISCS), we explore…
We present the far-ultraviolet (FUV) fluorescent molecular hydrogen (H_2) emission map of the Milky Way Galaxy obtained with FIMS/SPEAR covering ~76% of the sky. The extinction-corrected intensity of the fluorescent H_2 emission has a…
[abridged]CO rovibrational lines are efficient probes of warm molecular gas and can give unique insights into the inner 10 AU of proto-planetary disks. Recent studies have found a relation between the ratio of lines originating from the…
High-resolution infrared spectroscopy in the 2.3-4.6 micron region is reported for the peculiar A supergiant, single-lined spectroscopic binary HR 4049. Lines from the CO fundamental and first overtone, OH fundamental, and several H2O…
According to traditional gas-phase chemical models, O2 should be abundant in molecular clouds, but until recently, attempts to detect interstellar O2 line emission with ground- and space-based observatories have failed. Following the…
We present ultraviolet interstellar absorption line measurements for the sightline towards the O9.5 V star mu Columbae obtained with the Goddard High Resolution Spectrograph (GHRS) on board the Hubble Space Telescope. These archival data…
We report the detection of absorption lines by the reactive ions OH+, H2O+ and H3O+ along the line of sight to the submillimeter continuum source G10.6$-$0.4 (W31C). We used the Herschel HIFI instrument in dual beam switch mode to observe…
Aims: To calculate chemistry and gas temperature of evolving protoplanetary disks with decreasing mass or dust settling, and to explore the sensitivity of gas-phase tracers. Methods: The density and dust temperature profiles for a range of…