ABSTRACT We explore how dense filament widths, when measured using different molecular species, may change as a consequence of gas accretion towards the filament. As parcel falls into filament, it will experience density, temperature, and extinction values. The rate at which this environment changes affect differently abundance molecules. So, molecule that forms quickly better reflect local phy...

An algebraic principle for blind source separation is presented in this paper. This separation principle identi"es a (smaller) set of equations whose solutions can blindly extract non-Gaussian signals. The concept of `Mth-order uncorrelatednessa is introduced and it is proven that for Mth-order uncorrelated source signals, signals with nonzero kth-order cumulant (2(k)M) can always be extracted ...

We study the bending motion in the tetratomic molecules C2H2 (X̃ (1)Σg (+)), C2H2 (Ã (1)Au) trans-S1, C2H2 (Ã (1)A2) cis-S1, and X̃ (1)A1 H2CO. We show that the algebraic operator expansion method with only linear terms comprised of the basic operators is able to describe the main features of the level energies in these molecules in terms of two (linear) or three (trans-bent, cis-bent, and branch...

Maser is an acronym for microwave amplification by stimulated emission of radiation; in astronomy mega-masers are masers in galaxies that are ≥ 10(6) times more luminous than typical galactic maser sources. Observational studies of mega-masers can help us to understand their origins and characteristics. More importantly, mega-masers can be used as diagnostic tracers to probe the physical proper...

Table 1. Chemical composition of the Martian atmosphere. Spacecraft data are in black, ground-based spectroscopy is in red, spectroscopy from Earthorbiting observatories in blue. Species Mixing ratio Instrument CO2 0.955 GS N2 0.027 Viking/MS Ar 0.016 Viking/MS Ne 2.5 ppm Viking/MS Kr 0.3 ppm Viking/MS Xe 80 ppb Viking/MS H 2.7×10 cm Mariner/UVS O 0.01-0.02 Mariner/UVS O2 (1.2−2)×10 FPI CO 8×10...

We report the first high angular resolution imaging (3.4× 3.0) of deuterated formaldehyde (HDCO) toward Orion–KL, carried out with the Submillimeter Array (SMA). We find that the spatial distribution of the formaldehyde emission systematically differs from that of methanol: while methanol is found towards the inner part of the region, HDCO is found in colder gas that wraps around the methanol e...

We present VLBI observations of 6.7 and 12.2 GHz methanol masers in the star forming region NGC7538. Our results show the existence of two groups of masers. The first group exhibits a linear velocity gradient and forms a line in our VLBI map which is consistent with a rotating disc of masers seen edge-on around a massive star. The second group of masers are blueshifted with respect to the first...

The first and second hyperpolarizability beta and gamma are obtained for formaldehyde oligomers (H2CO)n (n = 1-7) using computational methods. We have used the finite field (FF) approach and hyperpolarizability density analysis (HDA) to predict the microscopic first and second nonlinear hyperpolarizability of the formaldehyde oligomers. The spatial contributions of electrons to the hyperpolariz...

conclusions trichotillomania may also be seen in preschool-aged children and may be associated with separation anxiety disorder. improper and late treatment can be associated with a worsening of the disorder. case presentation a 4.5-year-old girl without any psychiatric disorders in the family. she was cared for by her mother, and the child had a history of separation anxiety. after detection o...