H 3 + in the Central Molecular Zone of the Galactic Center: Revelation of a New Category of Gas
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Transcript of H 3 + in the Central Molecular Zone of the Galactic Center: Revelation of a New Category of Gas
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H3+ in the Central Molecular Zone of
the Galactic Center:Revelation of a New Category of Gas
Takeshi Oka
Department of Astronomy and Astrophysicsand Department of Chemistry,
The Enrico Fermi Institute, University of Chicago
Smiles, Kos, Greece, October 5, 2010
Tom Geballe Gemini Observatory
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The Central Molecular Zone (CMZ)
The Treasure House of H3+
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
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Discovery of the (J, K) = (3, 3) Metastable H3+
Metastable
27.2 days
20.4 days
Ortho I = 3/2
Para I = 1/2J
K
16 hrs8 hrs (3,3)
(2,2)
(1,1)
Pan and Oka, 1987, ApJ, 305, 518
(1,0)
Goto, McCall, Geballe, Usuda, Kobayashi, Terada, Oka, 2002, PASJ 54, 951
361 K
CO J = 1
(2,2) unstable
(3,3) metastable
(1,1) ground
T ~ 250 K
n ≤ 100 cm-3
Oka, Geballe, Goto, Usuda, McCall, 2005, ApJ, 632, 882
Spontaneous breakdown of symmetry
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The 2 band of H3+
Oka, Phys. Rev. Lett. 45, 531 (1980)
2 = 2521 cm1
2q
= 0.158 D
J
K
(3,3)
(2,2)
(1,1)
Breaking Symmetry
μ
(1,0)
R(3,3)l
R(2,2)l R(1,1)l
R(1,0)
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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
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CMZ
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Quintuplet Cluster
1° × 1° 140 pc × 140 pc
Super-massive clusters
GCS 3-2
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H3+ near the GC
Surprises
UKIRT Huge column density; rich profile Geballe et al. ApJ 1999Subaru (3,3) metastable and (2,2) unstable H3
+ Goto et al. PASJ 2002 Thermalization model analysis Oka & Epp ApJ 2004Gem. S Revelation of warm and diffuse gas Oka et al. ApJ 2005 Review Oka PNAS 2006Subaru From the center to 30 pc east Goto et al. ApJ 2008VLT Scrutiny of the Central core Goto et al. 2010Gem. S Synthesis Oka et al. 2011
30 pc
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Simple chemistry of H3+
Destruction H3+ + e → H + H + H
10-9
10-8
10-7
10-6
10-5
10-4
10-3
10-2
10-1
100
101
102
103
104
105
106
n(X
)
10-1
100
101
102
103
104
105
106
n(H)
Dense Clouds Diffuse Clouds
H2
HCO
C+H3
+
Production H2 → H2+ + e H2
+ +H2 →H + H3+
ζ
ζL = 2 ke N(H3+) (nC/nH)SV RX / f
7.3 ×10-8 cm3/s 1.6 ×10-4 1
(1.8-6.1) ×1015 cm-2 3
(ζL)min = (1.3 – 4.3) ×105 cm/s
ζ L
10-16 (0.4 – 1.4) kpc 10-15 40 - 140 pcGoto, Usuda, Nagata, Geballe, Indriolo, McCall, Suto, Henning, Morong, and Oka, ApJ, 668, 306 (2008)
dn(H3+)/dt = ζn(H2)
= ken(H3+)n(e)
McCall et al. Phys. Rev. A (2004)
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Lazio & Cordes, ApJ, 505, 715 (1998)
0.8 107-8 K
0.1 104-6 K 10 cm-3
0.1 50 K 104 cm-3
Previous concept of gas in the CMZneed to be drastically changed
Warm and diffuse gas> 0.2 250 K 102 cm-3
f:
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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
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CMZ
Opening a New Vista
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Search for bright and hot stars in the CMZGLIMPSE Point Source Catalogue of the Spitzer Space Telescope, L to M Ramírez et al. 2008, ApJS, 175, 147
2MASS photometry at J, H, and K bandsSkrutskie et al. 2006, AJ, 131, 1163
~ 2,000,000 stars
L < 7.5
~ 3,000 stars
(J – K)/(K – L) < 2.5K - L > 1.5J - K > 5
~ 300 stars
Low res. CO first overtone, 2.2 – 2.4μm
Candidate stars
Selected stars
High res. H3+ and CO spectroscopy
83 stars so far
10 new stars and 5 known stars
Star L J – K K – L (J – K)/(K – L)GCS3-2 3.03 7.33 3.16 2.32GCS4 3.71 7.65 3.45 2.22NHS21 4.62 7.03 2.76 2.55*NHS25 6.24 4.81* 1.27* 3.79*
brightness
youth
hotness
location
8
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New bright and hot dust embedded stars suitable for H3
+ spectroscopy
Geballe and Oka, ApJ, 709, L70-73 (2010)
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Two sightlines with remarkable H3+ spectrum
α
ι
Geballe and Oka, ApJ, 709, L70-73 (2010)
0 – 30 pc EastQuintuplet, α, ι
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Geballe and Oka, ApJ 709, L70-73 (2010)
Iota, the Monster
“iota”, 85 pc East, Sgr B
High T
Low n
(3,3)
(2,2)
Subaru May 4, 2010
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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
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αβ
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HCl
Cl−
HCl+ H2Cl+
H2
H−
H2+ H3
+
H2O
OH−
H2O+ H3O+
1 - 10
~ 3.3
Dariusz Lis
Floris van der Tak
107
?????
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http://www.dn.se/nyheter/vetenskap/the-frontrunners-of-the-nobel-prize-2010-1.1181788
Chemistry: Maybe the spectra of spectroscopy – a close up as well as all the way to outer space? William Moerner has developed a spectrometer that can discern individual molecules of elements. William Klemperer has developed methods to establish what molecules are present in the dust clouds between the stars. Maybe a combination of those two, and maybe Richard Zare and/or Allen Bard will be in on it.