Interstellar Matter: verschil tussen versies
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Nieuwe pagina aangemaakt met '=General= =Exams= ==15 June 2010== '''Small questions''' Ten terms that needed explaining e.g. '''Interstellar Gas''' * Describe the dominant heating and cooling pro…' |
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* Derive the accretion timescale for hydrogen on dust particles in a cloud with density <math>1000 cm^{-3}</math> when the dust gas ratio is 1 to 100. | * Derive the accretion timescale for hydrogen on dust particles in a cloud with density <math>1000 cm^{-3}</math> when the dust gas ratio is 1 to 100. | ||
* Give a way to from water molecules in the inter stellar gas. | * Give a way to from water molecules in the inter stellar gas. | ||
[[Categorie:Ms]] | |||
Versie van 15 jun 2010 12:46
General
Exams
15 June 2010
Small questions Ten terms that needed explaining e.g.
Interstellar Gas
- Describe the dominant heating and cooling processes for HI and HII regions
- Explain the cooling function for hydrogen gas. (the equation was given eq 3.30)
- Derive the equations for thermal instabilities in HI gas
- Is HII gas in pressure equilibrium? Motivate your answer
- Wat is cooling coronal gas?
Molecular spectra
- Explain the virba-rotational diagram of H2
- Why has H2 no dipole transitions
- Would HD have dipole transitions?
- Can the exitation temperature of H2 best be determines from the pure rotational lines or from vibra rotational transitions? Why is the difference between the 2 found temperature that big?
Dust
- What is the dominant process to from H2 in the ISM?
- What would that process be in very high density regions?
- What drives the interstellar chemistry in clouds?
- Are the low CO rotational transitions a good tracer of a cold dense molecular cloud? Motivate your answer.
- Derive the accretion timescale for hydrogen on dust particles in a cloud with density when the dust gas ratio is 1 to 100.
- Give a way to from water molecules in the inter stellar gas.