1 / 13

NGC7538-IRS1 N: modelling a maser disc

NGC7538-IRS1 N: modelling a maser disc. Michele Pestalozzi, M. Elitzur, J. Conway, R. Booth. Discs in high-mass star-forming regions. Zhang et al. 1998 Cesaroni et al. 2000 Shepherd et al. 2001 Sandell et a l. 2003. NGC7538-IRS1N: “the” disc. 6.7 GHz. Pestalozzi et al. 2004.

camden
Télécharger la présentation

NGC7538-IRS1 N: modelling a maser disc

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. NGC7538-IRS1 N:modelling a maser disc Michele Pestalozzi, M. Elitzur, J. Conway, R. Booth European Workshop on Astronomical Molecules, Zwolle 2004

  2. Discs in high-mass star-forming regions • Zhang et al. 1998 • Cesaroni et al. 2000 • Shepherd et al. 2001 • Sandell et al. 2003 European Workshop on Astronomical Molecules, Zwolle 2004

  3. NGC7538-IRS1N: “the” disc 6.7 GHz Pestalozzi et al. 2004 Minier et al. 1998 Gaume et al. 1995 European Workshop on Astronomical Molecules, Zwolle 2004

  4. The data disp. / LOS Vel. Pestalozzi et al. 2001 Minier et al. 1998 R.A. / DEC European Workshop on Astronomical Molecules, Zwolle 2004

  5. Comparison 6.7 / 12.2 GHz European Workshop on Astronomical Molecules, Zwolle 2004

  6. Keplerian rotating disc seen edge-on Gain per unit length between R0 and Ri: power-law (1 / rp) Amplification of a continuum background (Tb ~ 104K) 4. Maser is unsaturated Assumptions: Geometry European Workshop on Astronomical Molecules, Zwolle 2004

  7. Model (3.) (1.) (2.,4.) Free parameters: h, W European Workshop on Astronomical Molecules, Zwolle 2004

  8. Results 30 M8 (from others) 1000 AU in radius h = 0.39 6.7 GHz 12.2 GHz European Workshop on Astronomical Molecules, Zwolle 2004

  9. Velocity Coherence The ‘kink’ European Workshop on Astronomical Molecules, Zwolle 2004

  10. Important note IRAM 04191+1522 PdB, CS Belloche et al.2002 European Workshop on Astronomical Molecules, Zwolle 2004

  11. Advantages: • Masers allow to resolve the • same linear scales further away • 1 AU @ 1 kpc • Fine tracers of dynamics MASER vs Thermal emission European Workshop on Astronomical Molecules, Zwolle 2004

  12. Found and modelled a disc in NGC7538 30 M8, 1000 AU radius, h=0.39 Masers behave as thermal emission regarding optical depth Optimal tool to study small linear and dynamical scales at large distances Future: 3D modelling, outliers, satellite lines... Summary European Workshop on Astronomical Molecules, Zwolle 2004

  13. Thank you European Workshop on Astronomical Molecules, Zwolle 2004

More Related