Related papers: Systematic Molecular Differentiation in Starless C…
Determining the level of chemical complexity within dense starless and gravitationally bound prestellar cores is crucial for constructing chemical models, which subsequently constrain the initial chemical conditions of star formation. We…
Pre-stellar cores represent the initial conditions in the process of star and planet formation. Their low temperatures ($<$10 K) allow the formation of thick icy dust mantles, which will be partially preserved in the future protoplanetary…
Observations of low mass protostars which probe small enough size scales to be within likely CO depletion regions show the highest [NH2D]/[NH3] ratios yet measured, of 4--33%. These molecular D/H ratios are higher than those measured on…
High resolution molecular line observations of CS, HCO+, C18O and N2H+ were obtained toward the starless globule FeSt 1-457 in order to investigate its kinematics and chemistry. The HCO+ and CS spectra show clear self-reversed and…
The chemical evolution in high-mass star-forming regions is still poorly constrained. Studying the evolution of deuterated molecules allows to differentiate between subsequent stages of high-mass star formation regions due to the strong…
The results of single-dish observations of low- and high-J transitions of selected molecules from protoplanetary disks around two TTauri stars (LkCa15 and TWHya) and two HerbigAe stars (HD163296 and MWC480) are reported. Simple molecules…
The 1-50 GHz GBT PRIMOS data contains ~50 molecular absorption lines observed in diffuse and translucent clouds located in the Galactic Center, Bar, and spiral arms in the line-of-sight to Sgr B2(N). We measure the column densities and…
We studied sulfur chemistry of massive star-forming regions through single-dish submillimeter spectroscopy. OCS, O13CS, 13CS, H2S and SO transitions were observed toward a sample of massive star-forming regions with embedded UCH II or CH II…
High resolution molecular line observations of CS, HCO+, C18O and N2H+ were obtained toward the starless globule FeSt 1-457 in order to investigate its kinematics and chemistry. The HCO+ and CS spectra show clear self-reversed and…
We report the detection of complex molecules (HCOOCH_3, HCOOH and CH_3CN), signposts of a "hot core" like region, toward the low mass, Class 0 source NGC1333-IRAS4A. This is the second low mass protostar where such complex molecules have…
New HCN, HNC, and HCO+ measurements of 46 normal galaxies in transitions up to J=4-3 are included in a multitransition database covering HCN and HCO+ (130 galaxies) and HNC (94 galaxies). The near-linear luminosity relations are dominated…
We present the results of the first detailed millimeter and submillimeter molecular line survey of bright rimmed clouds, observed at FCRAO in the CO (J=1-0), C18O (J=1-0), HCO+ (J=1-0), H13CO+ (J=1-0), and N2H+ (J=1-0) transitions, and at…
We performed a carbon-chain molecule (CCM) survey toward four low-mass outflow sources, IRAS 04181+2655 (I04181), HH211, L1524, and L1598, using the 13.7 m telescope at the Purple Mountain Observatory (PMO) and the 65 m Tian Ma Radio…
Presented here are NOEMA interferometric observations of the neighboring hot cores W3(H$_{2}$O) and W3(OH). The presence of two star-forming cores at different evolutionary stages within the same parent cloud presents a unique opportunity…
The destiny of complex organic molecules (COMs) in star-forming regions is interlinked with various evolutionary phases. Therefore, identifying these species in diversified environments of identical star-forming regions would help to…
We have mapped the starless core TMC-1C in a variety of molecular lines with the IRAM 30m telescope. High density tracers show clear signs of self-absorption and sub-sonic infall asymmetries are present in N2H+ (1-0) and DCO+ (2-1) lines.…
We report new results from CARMA observations of both continuum and HCO+(1-0) emission at 3.4 mm from W3-SE, a molecular core of intermediate mass, together with the continuum observations at 1.1 and 0.85/0.45 mm with the SMA and JCMT. A…
We present a near-infrared extinction study of nine dense cores at evolutionary stages between starless to Class I. Our results show that the density structure of all but one observed cores can be modeled with a single power law rho \propto…
We investigate the evolution of molecular abundance in quiescent protoplanetary disks which are presumed to be around weak-line T Tauri stars. In the region of surface density less than $10^2$ g cm$^{-2}$ (distance from the star $\gtrsim…
We present CS(3-2) and DCO+(2-1) observations of 94 starless cores and compare the results with previous CS(2-1) and N2H+(1-0) observations to study inward motions in starless cores. The velocity shifts of the CS(3-2) and (2-1) lines with…