We report on a recent spectral line survey of the planetary nebula (PN) NGC7027 using the Arizona Radio Observatory (ARO) 12m telescope and the Heinrich Hertz Submillimeter Telescope (SMT) at millimeter wavelengths. The spectra covering the frequency ranges 71–111GHz, 157–161GHz, and 218– 267GHz were obtained with a typical sensitivity of rms < 8mK. A total of 67 spectral lines are detected, 21...

We conducted a systematic study of the irradiation of crystalline water ice in an ultrahigh vacuum chamber at pressures of about 10!10 torr. Crystalline water ices of 115 " 30 nm thickness were irradiated with energetic electrons at 12, 40, 60, and 90 K to simulate energetic particle interaction with solar system and interstellar water ices. The production rates of molecular hydrogen (H2), mole...

The illuminating source of the photodissociation region associated with the reÑection nebula NGC 7023 is HD 200775. We probed the foreground atomic and molecular material through diagnostics observed in absorption against the background star. Ground-based measurements of Na I, K I, and Ca II and of the molecules CH, CH`, and CN were analyzed in order to extract the physical conditions 2 for thi...

We report on the detection with the Infrared Space Observatory (ISO) of a molecular band at 57.5 μm (174 cm) in carbon-rich evolved stars and in Sgr B2. Taking into account the chemistry of these objects the most likelihood carrier is a carbon chain. We tentatively assign the band to the ν5 bending mode of C4 for which a wavenumber of 170-172.4 cm has been derived in matrix experiments (Withey ...

We used the IRAM Interferometer to obtain sub-arcsecond resolution observations of the high-mass star-forming region W3(OH) and its surroundings at a frequency of 220 GHz. With the improved angular resolution, we distinguish 3 peaks in the thermal dust continuum emission originating from the hot core region ≈ 6 (0.06 pc) east of W3(OH). The dust emission peaks are coincident with known radio co...

We have investigated the physical and chemical status of the pre-protostellar core B68. A previous extinction study suggested that the density profile of B68 is remarkably consistent with a Bonnor-Ebert sphere with 2.1 M at 16 K. We mapped B68 in C3H2, CCS, and NH3 with the Deep Space Network (DSN) 70m telescope at Goldstone. Our results show that the NH3 peak coincides with the dust continuum ...

Context. Theories of the origins life propose that early cell membranes were synthesised from amphiphilic molecules simpler than phospholipids, such as fatty alcohols. The discovery in interstellar medium (ISM) ethanolamine, simplest phospholipid head group, raises question whether simple are also space. Aims. We investigate precursors alcohols present ISM. Methods. To do this, we have carried ...

ABSTRACT Hydroxyl ($\rm OH$) is known to form efficiently in cold gas (T ∼ 100 K) along with the molecule $\rm H_2$ and can be used as an efficient tracer of diffuse molecular interstellar medium (ISM). Using a simple formalism describing H\, I/H_2$ transition reduced network major chemical reactions, we present semi-analytical prescription estimate abundances O-bearing molecules ISM. We show t...

Massive star formation exhibits an extremely rich chemistry. However, not much evolutionary details are known yet, especially at high spatial resolution. Therefore, we synthesize previously published Submillimeter Array high-spatial-resolution spectral line observations toward four regions of highmass star formation that are in various evolutionary stages with a range of luminosities. Estimatin...