250 K) and diffuse (≤ 100 cm -3 ) gas and high ionization rate (ζ > 10 -15 s -1 ) in the Central Molecular Zone by the Infrared Spectrum of H 3 + Takeshi Oka Department of Astronomy and Astrophysics and Department of Chemistry The Enrico Fermi Institute, University of Chicago tar formation under extreme conditions: the Galactic center at the Besançon Observatory, December 7, 2010 m Geballe Gemini Observatory wa Goto Max-Planck Institut für Astrono
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Star formation under extreme conditions: the Galactic center
Revelation of a vast amount of warm (~ 250 K) and diffuse (≤ 100 cm -3 ) gas and high ionization rate ( ζ > 10 -15 s -1 ) in the Central Molecular Zone by the Infrared Spectrum of H 3 + Takeshi Oka Department of Astronomy and Astrophysics and Department of Chemistry - PowerPoint PPT Presentation
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Revelation of a vast amount of warm (~ 250 K) and diffuse (≤ 100 cm-3) gas and high ionization rate (ζ > 10-15 s-1)
in the Central Molecular Zone by the Infrared Spectrum of
H3+
Takeshi Oka
Department of Astronomy and Astrophysics and Department of Chemistry
The Enrico Fermi Institute, University of Chicago
Star formation under extreme conditions: the Galactic center
at the Besançon Observatory, December 7, 2010
Tom Geballe Gemini ObservatoryMiwa Goto Max-Planck Institut für Astronomie
2005 Revelation of warm and diffuse gass near GC Oka, Geballe, Goto, Usuda, McCall, ApJ 632, 882
1999 High H3+ abundance in the Galactic center
H3+, the new astrophysical probe
+
1951
19701973
1996
1980 Oka, Phys. Rev. Lett. 45, 531Laboratory Spectrum
1996Geballe, Oka, Nature 384, 334
Interstellar H3+, Discovery, Dense Clouds
H
H2
H3+
1989 - 95
2002 Metastable H3+, Discovery, Galactic center
Goto, McCall, Geballe, Oka, et al. PASJ 54, 951
1975 HC5N, HC7N, HC9N
2008 Ubiquity Central 30 pc of the Galactic center Goto, Geballe, Oka, et al. ApJ 688, 306
T.G.
2010 Exploring wider regions of the Galactic center Geballe, Oka, ApJ, 709, L70
92
10~
a
Telescopes and spectrometersTelescope D Spectrom. λ/Δλ UKIRT 3.8 m CGS4 40,000 Mauna Kea 1982 Subaru 8.2 m IRCS 20,000 Mauna Kea 2000Gemini South 8 m Phoenix 60,000 Cerro Pachon 2003VLT 8.2 m CRIRES 100,000 Cerro Paranal 2006 Gemini North 8 m GENIRS 18,000 Mauna Kea 2011
Subaru UKIRTGemini South
VLT
Gemini North
Quintuplet Cluster
1° × 1° 140 pc × 140 pc
Super-massive clusters
GCS 3-2
High abundance of H3+ in the CMZ
CMZ
R(1, 1)u R(1, 0)
T. R. Geballe, Phil. Trans. Roy. Soc. Lond. A358, 2503 (2000)
3 × 1014 cm-2
10-5
10%
400 pc
(J, K) = (3, 3) metastable H3+, the fingerprint of GC
Chandra 20 pc × 20 pc (0.5 – 8) keV Muno et al. ApJ 589, 225 (2003)
Warwick, Sakano Decourchelle (2006) Revnivtsev et al. (2006)
X-ray: Chandra comes to rescue
Remarkable similarity between velocity profilesof H3
+ toward Iota and H2O+, CH+ toward Sgr B2 Herschel observations of ortho- and para-oxidaniumyl (H2O+) in spiral arm clouds toward Sgr B2(M) ⋆
P. Schilke,1,2 C. Comito,2 H. S. P. M¨uller,1 E. A. Bergin,3 E. Herbst,14 D. C. Lis,4 D. A. Neufeld,20 T. G. Phillips,4 T. A. Bell,4 G.A. Blake5 E. Caux,6,7 C. Ceccarelli,8 J. Cernicharo,9 N. R. Crockett,3 F. Daniel,9,10 M.-L. Dubernet,11,12 M. Emprechtinger,4 P. Encrenaz,10 M. Gerin,10 T. F. Giesen,1 J. R. Goicoechea,9 P. F. Goldsmith,13 H. Gupta,13 C. Joblin,6,7 D. Johnstone,15 W. D. Langer13 W. B. Latter16 S. D. Lord,16 S. Maret,8 P. G. Martin,17 G. J. Melnick,18 K. M. Menten,2 P. Morris,16 J. A. Murphy,19 V. Ossenkopf,12,21 J. C. Pearson,13 M. P´erault,10 R. Plume,22 S.-L. Qin,13 S. Schlemmer,1 J. Stutzki,1 N. Trappe,19 F. F. S. van der Tak,21 C. Vastel,6,7 S. Wang,3 H. W. Yorke,13 S. Yu,13 N.Erickson,25 F.W. Maiwald,13 J. Kooi,4 A. Karpov,4 J. Zmuidzinas,4 A. Boogert,4 R. Schieder,1 and P. Zaal21A&A June 22 2010
Geballe & Oka, 2010, ApJ, 709, L70
H3+ R(1,1)l
H2O+ 111← 000
H2O+ 110← 101
17 pc
3 kpc ScutumSgittarius
E. Falgarone et al. 2010
NH3 Metastable rotational levels
0 1 2 30
1
2
3
J
K
NH3
ΔK = 0
0 1 2 30
1
2
3
J
K
NH3
NH3 Metastable rotational levels
Δk = 3
Metastable rotational levels
0
1
2
3
JNH3
μ
T. Oka, F. O. Shimizu, T. Shimizu, J. K. G. Watson, ApJ 165, L15 (1971)