1 / 32

M82 as Playground for Galaxy and Star Formation

M82 as Playground for Galaxy and Star Formation. Wing-Huen Ip Institute of Astronomy National Central University Weihai, August 11, 2005. Outline. Introduction Star Formation History – Density Wave vs. SSPSF M82 – A Prototype of Starburst Galaxy M82 – Dusty Superwind and H  Cap

jonny
Download Presentation

M82 as Playground for Galaxy and Star Formation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. M82 as Playground for Galaxy and Star Formation Wing-Huen Ip Institute of Astronomy National Central University Weihai, August 11, 2005

  2. Outline • Introduction • Star Formation History – Density Wave vs. SSPSF • M82 – A Prototype of Starburst Galaxy • M82 – Dusty Superwind and H Cap • Disk-Halo Interaction • Massive Coronas of Galaxies • Summary

  3. Learning from BATC • Juei-Hua Hu: NGC 2168 (Exoplanets/V*) NGC 381 V* SLT 20-cm (Exoplanets/V*) • Zhong-Yi Lin: Comets Q2; 9P/Tempel 1 (Deep Impact) • Chia-Hao Hsia: H imaging of PNe (also 2.16 m) H imaging of nearby galaxies (LOT) to compare with 2Mass NIR data

  4. NGC 6946 From Yi-Tong Chen

  5. Large-scaled Star Formation Process • Density Wave Theory: Orbital velocity pattern plus gas density enhancement at spiral arms • Stochastic Self-Propagating Star Formation: Pressure waves generated by supernovae or massive stars plus differential rotation

  6. Test Cases • Dwarf galaxies (no spiral arms) • Starburst galaxies (nuclear regions) • Both types provide information on star formation and galaxy building processes in early universe (Lyman forests with metal absorption lines -> massive coronas ….)

  7. The Rosette Nebula

  8. Henize 70 in LMC 30 Doradus in LMC

  9. 2.3 Elephant Trunk of the Rosette Nebula

  10. LOT Kenboo Wu NCU

  11. http://amundsen.swarthmore.edu/SHASSA/

  12. Diffuse Ionized Gas (DIG) or Reynold Layer

  13. H emission 11 Kpc above M82Devine and Bally (1999) Continuous H emission out to 11-12 kpc from nuclues until a cap- like structure Shell-like feature (colliminated super- wind?) with blueshifted speed of 50-200 km/s Formation of bow shock from the expansion of the superwind? Question: Any similar structure in other wavelengths (BATC obs.?)

  14. Other Important Obs. • Very extended soft X-ray emission in good correlation with H emission (kT = 0.87 keV); Lehnert et al., 1999; Stevens et al., 2004 • Shock heating (galactic superwind speed ~ 800 km/s); Lehnert et al., 1999. • Galex obs. of UV halos suggested emission of cold gas and dust (until the H cap); Hoopes et al., 2005.

  15. Massive Coronas of Galaxies • Dark matter halos contain about 10 times the mass of the visible baryonic matter. • Mass in the extended corona (r ~ 300 kpc) of a spiral galaxy in ionized hot gas could be much larger than the “condensed” baryons (Fukugita and Peebles, 2005) • Half coronal hot plasma (kT ~ 0.3 kev) and half dark matter! • Star fomration rate balanced by plasma condensation rate!

  16. NGC 6946 From Yi-Tong Chen

  17. Summary Still many puzzles and many challenging issues inspired by M82!

More Related