October, 1970

H2S2

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 H3

+ and 13CO: GCIRS 3 and GCIRS 1W

66th OSU International Symposium, June 21, 2011

Miwa Goto, Max-Planck-Institute for Astronomy, Heidelberg Tomonori Usuda, Subaru Telescope, HiloThomas 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+

λε+ ε-η+

θ-

θ+

δ+

30 pc

Oka, Geballe, Goto, Usuda, McCall, 2005, ApJ, 632, 882GCS 3-2

Goto, Usuda, Nagata, Geballe, McCall, Indriolo,Suto, Henning, Morong, Oka, 2008, ApJ, 688, 306

, Geballe, Oka, 2010, ApJ, 709, L70

T ~ 250 Kn < 100 cm-3

L > 2.2 105 cm/s = 2 10-15 s-1 L > 35 pc

N. Z. Scoville, 1972 T. Sawada et al. 2001

The Expanding Molecular RingT. Sawada et al. 2004

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 Cluster8.4” 0.33 pc

The ISAAC L-band image of the Galactic center showing most of the named sources (from Viehmann et al. 2005)

H3+ and 13CO spectra toward GCIRS 3 and GCIRS 1W

Warm and diffuse gas

(3,3)

(2,2)

(1,1)

27 days361 K

H3+ and 13CO 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 kL N(H3+) (nC/nH)SV RX / f(H2)

1.8 ×10-9 cm3/s 1.6 ×10-4 1

1.0 ×1015 cm-2 3

L = 2 ke N(H3+) (nC/nH)SV RX / f(H2)

~ 1700 cm s-1

if L = 0.5 pc, = 1.1 10-15 s-1

Ubiquity of H3+

Sgr A* to 30 pc East

30 pc

1.00

0.95

0.90

0.85

0.80

0.75

0.70

-200 -150 -100 -50 0 50 100

GCS 4

NHS 21

NHS 25

NHS 42

FMM 361

Goto, et al. 2008, ApJ, 688, 306