Difference between revisions of "Talk:C-WAYS Spring work"
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Different conclusions from Getman. An age gradient is not found in the south-north direction of the globule; not all star formation in globule is by triggered star formation. NO alternative method given. | Different conclusions from Getman. An age gradient is not found in the south-north direction of the globule; not all star formation in globule is by triggered star formation. NO alternative method given. | ||
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Latest revision as of 16:35, 6 May 2012
Getman 2006 X-Ray Study of Triggered Star Formation and Protostars in IC 1396N
An observation of IC 1396N with Chandra, so X-ray light. How long (total time) was the observation? 30 ks = 30 kilo seconds = 30,000 seconds = 500 min = 8.33 hours - Is this a long observation? I got the impression from the reading that it was short.
Intro - What will be useful in this section for us?
The cometary globule this study looks at is BRC 38?
Nice list of indicators of star formation in IC 1396N. Things we should know about
-IRAS source 21391 +5802
-H2O masers
-molecular outflows
-HH flows
-clusters of IR embedded sources
-radio mm portostars
Explanation of RDI - easy to understand. Explanation of why an x-ray study - I was surprised. Didn't think about magnetic fields being active in YSO.
"2.1 - 2.3 Chandra Observation & Source List - The meat for us!"
The most important things here are the tables and figures. Locations given for the found sources and correlations to 2MASS. Will we eventually understand what each of these columns mean?
2.1 - Interesting that 8 corrections were made to the data. EIGHT pg 317-8 Data reduced to 117 point sources (listed in table 1); 66 of those correlated with 2MASS; 5 newly identified
Sections 3, 4 & 5 - Interesting things about IC 1396N
3.1-3.4 Data reduced to sources coming from star formation. 25 sources are probable members of the globule. Sources classified as class 0, I, II, III.
4.1- 4.3 It was interesting that there was flaring going on. Are YSO variable in the their light output, like a variable star? 4.3 was hard to understand. I have to sort out wavelengths and energies associated with each em light band.
5.1-5.3 Figure 10 a - This is a great picture of results of using different types of observations and even of resolution. Why correlation with other studies is needed. Figure 10 c - Source 66 and 68 are so much brighter than the others. Interesting. It was also interesting that #66 is the brightest x-ray object in IC 1396N. What does it mean that it is 'one of the most heavily absorbed sources'?
Questions
1. Does this symbol mean of the Sun? M⊙ = mass in relation to the Sun?
2. What is IMF - initial mass function? pg 328, last full paragraph
3. What is MedE? pg 331 5.2
4. What is intervening column density? pg 332 5.3 2nd paragraph
5. What is extinction? pg 332 5.3 3rd paragraph
"Section 6 & 7 - Science questions and summary"
Section 6 pulls the info from the study into the larger science questions - What do these results say about triggered star formation and the two initiation methods mentioned? It seems that RDI (radiation driven implosion) is supported.
I like section 7's summary. Easy to understand and I like the list of classifications of the 25 YSO.
Beltran 2009 The stellar population and complex structure of the bright-rimmed cloud IC 1396N
This article discusses the structure of this cloud and gives positions of everything it talks about. 18 pages worth of tables! Their conclusions are also different than the previous paper about star formation.
I found it interesting that individual sources we read about in the previous article have been resolved into several sources by the time this one was written.
Questions
1. They mention that bluer YSO mean older and redder are younger -- this is opposite of main sequence stars
2. What is on source images and off sources images? Why do you do this? this is to try and adjust for background light
The images went through 5 set of corrections or adjustments before photometry
3.2 The authors conclude not all star formation is triggered star formation in this cloud. Then what else is there?
3.3.1 All this info about H2 knots. Dense material. Does the red and blue shift indicate spinning? No, it is looking at a jet face on but not perpendicular
3.3.2 H2 flows are complicated. A lot of assumptions are made.
4. 736 sources found in all three bands - J, H K' 128 sources found only in HK' 67 sources found only in K' 79 sources found only in JH
Different conclusions from Getman. An age gradient is not found in the south-north direction of the globule; not all star formation in globule is by triggered star formation. NO alternative method given.
