Rodrigo%20Parra%20%20John%20Conway%20%20Ylva%20Pihlstrom

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Rodrigo Parra John Conway Ylva Pihlstrom
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Roadmap
Diffuse Compact Two phase gas??
Clumpy medium?
Formalism
Proposed model
Monte Carlo
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IIIZw35

• Single dish (Staveley-Smith et al. 1986)
• VLBA (Trotter et al. 1997)
• G. VLBI (Diamond et al. 1999)
• EVN MERLIN (Pihlström et al. 2001)

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Model
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Path length
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Truncated series
5 mas
G. VLBI
30 mas
EVN MERLIN
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Solving the equations
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Solutions
A2 12 A1 72
?0
P1 gt 500
?
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Monte-Carlo simulations
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Results - Continuum
Pihlström et al., 2001
EVN MERLIN 33.0 x 28.7 mas
Simulation 30 x 30 mas
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Results - Spectrum
Staveley Smith et al., 1986 Trotter et al., 1997
Simulation
Single dish (JBT)
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Results - OH maser emissionEVN MERLIN
Pihlström et al., 2001
EVN MERLIN 33.0 x 28.7 mas
Simulation 30 x 30 mas
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Results - OH maser emissionVLBI
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Arp 220 ?
Lonsdale et al., 1998
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Conclusions Future
The model reproduces both, the compact and smooth
components of the maser emission, without the
need of a two-phase gas.
The concept of statistical gain is an accurate
representation of clumpy media.
Application of the model to other sources (ie.
Arp 220, Mrk 273)
Improve the model Line widths, coherence, beaming
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Thank you!
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Answers
50pc
Ionised Thermal wind

• -Inward Propagating starburst Ring
• Gas clouds in ring not bound
• - Orbital/random velocity of 50km/s at r25pc,
  enclosed mass is 10E8 solar masses

Quiescient Disk