October, 1970 H2S2H2S2 March 28-31, 1966, APS Durham, NC April 22, 1966, Invitation to give a seminar

Scrutiny of the Central Parsec of the Galactic Center by Infrared Spectra of H 3 + and 13 CO: GCIRS 3 and GCIRS 1W 66th OSU International Symposium, June 21, 2011 Miwa Goto, Max-Planck-Institute for Astronomy, Heidelberg Tomonori Usuda, Subaru Telescope, Hilo Thomas R. Geballe, Gemini Observatory, Hilo Farhad Yusef-Zadeh, Northwestern University, Evanston Nick Indriolo, and Ben J. McCall, University of Illinois at Urbana-Champaign, Urbana Takeshi Oka, University of Chicago, Chicago Harvey Liszt, National Radio Astronomy Observatory

α+α+ λ ε+ε+ ε-ε- η+η+ θ-θ- θ+θ+ δ+δ+ 30 pc Oka, Geballe, Goto, Usuda, McCall, 2005, ApJ, 632, 882 GCS 3-2 Goto, Usuda, Nagata, Geballe, McCall, Indriolo, Suto, Henning, Morong, Oka, 2008, ApJ, 688, 306 ,  Geballe, Oka, 2010, ApJ, 709, L70 T ~ 250 K n < 100 cm -3  L > 2.2  10 5 cm/s  = 2  s -1  L > 35 pc

N. Z. Scoville, 1972 T. Sawada et al The Expanding Molecular Ring T. Sawada et al Molecular face-on view of the GC R ~ 180 pc 130 pc 101 pc Reid, Menten, Zheng, Brunthaler, Xu, ApJ, 2009

J. Kormendy & R. C. Kennicutt, 2004, ARA&A, 42, 603

The Central Cluster 8.4” 0.33 pc The ISAAC L-band image of the Galactic center showing most of the named sources (from Viehmann et al. 2005)

H 3 + and 13 CO spectra toward GCIRS 3 and GCIRS 1W Warm and diffuse gas (3,3) (2,2) (1,1) 27 days 361 K

H 3 + and 13 CO spectra toward GCIRS 3 and GCIRS 1W Velocity profiles and radial location of gas Subtract spiral arms Expanding Mol. Ring Inner Molecular gas  140 km s -1

Dense cloud near Sgr A* toward GCIRS 3 N(1,1) = 1.89 ± 0.31 cm -2 N(2,2) = 2.05 ± 0.57 cm -2 N(3,3) = 2.78 ± 0.30 cm -2 T ~ 300 K

Ionization rate  L = 2 k L N(H 3 + ) (n C /n H ) SV R X / f(H 2 ) 1.8 ×10 -9 cm 3 /s1.6 × ×10 15 cm -2 3  L = 2 k e N(H 3 + ) (n C /n H ) SV R X / f(H 2 ) ~ 1700 cm s -1 if L = 0.5 pc,  = 1.1  s -1

Ubiquity of H 3 + Sgr A* to 30 pc East 30 pc Goto, et al. 2008, ApJ, 688, 306