Dust and the Gas Phase Composition of Dense Clouds
نویسندگان
چکیده
منابع مشابه
Dense Star-forming Gas and Dust in the Magellanic Clouds
The early stages of the star formation process are closely related to the condition of the parent interstellar medium, in particular to the heating/cooling balance, which itself is a function of ambient conditions. Important questions such as dust abundance, size distribution, temperature distribution, fraction of molecular gas, fraction of dense gas, gas surface density and total amount of gas...
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The interstellar medium of Centaurus A (NGC 5128) has been studied extensively in recent years, using mostly molecular lines tracing low to medium density gas (500 to several 10 cm). The amount and distribution of the dense molecular gas was largely unknown. Here we present new millimeter data of the HCN(1–0), CS(2–1), and CS(3–2) rotational transitions towards the nearby radio galaxy Centaurus...
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We report on GHRS observations which reveal conspicuous differences in the absorption spectra of two nearby stars, close to each other. The star HD102065 lies behind a cloud in Chamaeleon with unusually strong mid–IR emission, indicating a large abundance of very small dust particles. Along this line of sight, 5% of the gas (about 6 1019 cm−2) is at large velocities (up to -50 km s−1) compared ...
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ژورنال
عنوان ژورنال: Symposium - International Astronomical Union
سال: 1989
ISSN: 0074-1809
DOI: 10.1017/s0074180900125288