Results 271 to 280 of about 56,054 (306)
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Carbon Dioxide in Star-forming Regions
The Astrophysical Journal, 2000We consider the gas-phase chemistry of CO2 molecules in active regions. We show that CO2 molecules evaporated from dust in hot cores cannot be efficiently destroyed and are in fact copiously produced in cooler gas. When CO2-rich ices are sputtered in strong MHD shock waves, the increase in atomic hydrogen, due to H2 dissociation by ion-neutral ...
, Charnley, , Kaufman
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Vistas in Astronomy, 1988
With recent improvements in the mm-wave, IR and high-sensitivity optical observations various new features of star formation embedded in dark clouds have been revealed. These are expanding shock fronts due to newly formed massive stars, gaseous disks surrounding proto stars, the energetic bipolar molecular flows, and the weRlcollimat'ed ionized jets ...
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With recent improvements in the mm-wave, IR and high-sensitivity optical observations various new features of star formation embedded in dark clouds have been revealed. These are expanding shock fronts due to newly formed massive stars, gaseous disks surrounding proto stars, the energetic bipolar molecular flows, and the weRlcollimat'ed ionized jets ...
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The star-forming region in Orion KL
Astronomy Letters, 2003We have studied the fine structure of the active H2O supermaser emission region in Orion KL with an angular resolution of 0.1 mas. We found central features suggestive of a bipolar outflow, bullets, and an envelope which correspond to the earliest stage of low-mass star formation.
Matveyenko, L. I. +3 more
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Magnetic massive stars in star forming regions
Proceedings of the International Astronomical Union, 2018AbstractOne idea for the origin of magnetic fields in massive stars suggests that the magnetic field is the fossil remnant of the Galactic ISM magnetic field, amplified during the collapse of the magnetised gas cloud. A search for the presence of magnetic fields in massive stars located in active sites of star formation led to the detection of rather ...
Swetlana Hubrig +2 more
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2012
Satisfactory assessments of star forming regions in the Galaxy are essential for the understanding of early stellar evolution and today a vast amout of astronomical studies are available. Star-forming regions distinguish themselves from other regions in the Galaxy. Many different physical processes are displayed with high levels of variability, a large
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Satisfactory assessments of star forming regions in the Galaxy are essential for the understanding of early stellar evolution and today a vast amout of astronomical studies are available. Star-forming regions distinguish themselves from other regions in the Galaxy. Many different physical processes are displayed with high levels of variability, a large
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Molecular shocks in star forming regions
Astrophysics and Space Science, 1995The role of excited molecular hydrogen as a powerful observational tool is examined in the context of shock phenomena in molecular clouds, particularly in star forming regions. Conclusions that may be drawn from line intensities and line profiles, and the properties of J and C shocks in a bow shock structure are discussed.
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Acetaldehyde in star-forming regions
Advances in Space Research, 2004Abstract Observations of acetaldehyde (CH 3 CHO) in a survey of nine star-forming regions are presented. Emission is clearly detected from both the A and E symmetry states in the 4 04 –3 03 and 5 05 –4 04 transitions. Both the range of the measured CH 3 CHO column densities (∼4×10 12 –10 14 cm −2 ), and the derived fractional abundances, are in ...
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The Chemistry of Star Forming Regions
1998Abstract The first generation of stars formed in gas that was almost entirely hydrogen and helium, and the chemistry that was important during their births, is treated in Chapter 3. In this chapter we focus on star forming regions in which elements more massive than helium a.re important in the chemistry that controls star formation ...
T W Hartquist, P Caselli
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Chemistry of Star-Forming Regions
2017Birth of protostars significantly affects chemical compositions of parent molecular clouds. Observational results of low-mass and high-mass star-forming regions are summarized, which show significant chemical differentiation within a source as well as among sources.
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Masers in Star-Forming Regions
1999The subject of astronomical masers is now more than forty years old, and as a consequence, several good reviews have appeared in print. For the readers who want to enter the subject of astronomical masers in a serious way, we want to recommend two reviews (Elitzur 1982; Reid and Moran 1988) and a book (Elitzur 1992a).
N. D. Kylafis, K. G. Pavlakis
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