Difference between revisions of "ProtostarsInNGC281"

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===Introduction to NGC 281===
 
===Introduction to NGC 281===
 
NGC 281 is an active star-forming nebulosity about 2.81± 0.24 kpc or 9200 light-years away (Sato et al. 2008) at a relatively high galactic latitude (<math>\alpha</math>2000=00h52m, <math>\delta</math>2000=+56d34m or l=123.1deg, b= -6.3deg) in the constellation Cassiopeia. <br/><br/>
 
NGC 281 is an active star-forming nebulosity about 2.81± 0.24 kpc or 9200 light-years away (Sato et al. 2008) at a relatively high galactic latitude (<math>\alpha</math>2000=00h52m, <math>\delta</math>2000=+56d34m or l=123.1deg, b= -6.3deg) in the constellation Cassiopeia. <br/><br/>
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'''NGC 281 contains several distinct regions:'''  
NGC 281 contains several distinct regions:'''  
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*an HII emission region Sharpless 184 of diameter 20 arcminutes containing the young galactic cluster IC 1590 centered about the OB star trapezium system HD5005.<br/>
*an HII emission region Sharpless 184 of diameter 20 arcminutes containing the young galactic cluster IC 1590 centered about the OB star trapezium system HD5005 (Guetter & Turner 1997). <br/>
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*Two quite distinct CO molecular clouds:
*Two quite distinct CO molecular clouds (Elmegreen & Lada 1978):
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**The southeastern CO region (N281A) with local standard of rest (LSR) similar to that of the HII region itself (-30.5 km/s vs. -26.5 km/s). This region contains highly recognizable “pillars of creation.” These pillars are known to contain newborn stars as a result of triggering from the nearby OB star trapezium system.  
**The southeastern CO region (N281A) with local standard of rest (LSR) similar to that of the HII region itself (-30.5 kms-1 vs. -26.5 kms-1) (Leisawitz 1988). This region contains highly recognizable “pillars of creation.” These pillars are known to contain newborn stars as a result of triggering from the nearby OB star trapezium system.  
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**NGC 281 West (N281B), a molecular cloud in the southwestern region with three distinct clumps (NE, NW and S) (Megeath & Wilson 1997). The region is heavily obscured by dust and has a LSR (+44 km/s) quite different from that of its eastern neighbor and the HII region it borders.  
 
 
**NGC 281 West (N281B), a molecular cloud in the southwestern region with three distinct clumps (NE, NW and S) (Megeath & Wilson 1997). The region is heavily obscured by dust (Guetter & Turner 1997) and has a LSR (+44 kms-1) quite different from that of its eastern neighbor and the HII region it borders (Leisawitz 1988).  
 
  
  

Revision as of 13:33, 6 December 2013

The idea is to start gathering two items:

  1. Relevant figures
  2. Text and references.


Abstract

  • Carol.


Introduction to NGC 281

NGC 281 is an active star-forming nebulosity about 2.81± 0.24 kpc or 9200 light-years away (Sato et al. 2008) at a relatively high galactic latitude (Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://en.wikipedia.org/api/rest_v1/":): {\displaystyle \alpha} 2000=00h52m, Failed to parse (MathML with SVG or PNG fallback (recommended for modern browsers and accessibility tools): Invalid response ("Math extension cannot connect to Restbase.") from server "https://en.wikipedia.org/api/rest_v1/":): {\displaystyle \delta} 2000=+56d34m or l=123.1deg, b= -6.3deg) in the constellation Cassiopeia.

NGC 281 contains several distinct regions:

  • an HII emission region Sharpless 184 of diameter 20 arcminutes containing the young galactic cluster IC 1590 centered about the OB star trapezium system HD5005.
  • Two quite distinct CO molecular clouds:
    • The southeastern CO region (N281A) with local standard of rest (LSR) similar to that of the HII region itself (-30.5 km/s vs. -26.5 km/s). This region contains highly recognizable “pillars of creation.” These pillars are known to contain newborn stars as a result of triggering from the nearby OB star trapezium system.
    • NGC 281 West (N281B), a molecular cloud in the southwestern region with three distinct clumps (NE, NW and S) (Megeath & Wilson 1997). The region is heavily obscured by dust and has a LSR (+44 km/s) quite different from that of its eastern neighbor and the HII region it borders.


Protostar basics

  • Lynn


Two Scenarios for Star Formation

  • Peggy

Spontaneous vs. Triggered Star Formation

• Most star formation begins due to spontaneous processes on a galactic scale, given sufficient time and material free fall will result in star formation.
• An outside source of energy can trigger the formation of a star before conditions become sufficient for free fall, leaving sequentially younger stars in its path while clouds broken into filaments by magnetic fields will show a filamentary pattern of protostars.

Star formation in a “controlled” environment

• small regions where the formation conditions except for the trigger are the same
• physical and geographical characteristics of protostars created can therefore be related to triggering mechanism.

NGC 281

• HII emission containing the young galactic cluster IC 1590, OB star trapezium system HD5005 with what appears to be two distinct start forming regions around it;
• Triggered East side with “pillars of creation”, newborn stars as a result of triggering from the nearby OB star trapezium system.
• Crowded West side with three distinct clumps (NE, NW and S) of star formation.

Herschel data

  • Carol


Spitzer data

  • Melissa


Source Identification

  • Carol


Photometry Using APT

  • Lynn


Final Source Selection

  • Melissa
  • Peggy


Analysis & Results

  • TBD


Discussion & Conclusions

  • TBD


List of References

  • TBD


List of Authors & Affiliations

  • Carol