H 3 + in the Central Molecular Zone of the Galactic Center: Revelation of a New Category of Gas

H3+in the Central Molecular Zone of the Galactic Center: Revelation of a New Category of Gas Takeshi Oka Department of Astronomy and Astrophysics and Department of Chemistry, The Enrico Fermi Institute, University of Chicago Tom Geballe Gemini Observatory Smiles, Kos, Greece, October 5, 2010

The Central Molecular Zone (CMZ)The Treasure House of H3+ R(1, 1)u R(1, 0) 3 × 1014 cm-2 10-5 10% T. R. Geballe, Phil. Trans. Roy. Soc. Lond. A358, 2503 (2000) CMZ 400 pc

Discovery of the (J, K) = (3,3) Metastable H3+ Goto, McCall, Geballe, Usuda, Kobayashi, Terada, Oka, 2002, PASJ 54, 951 Spontaneous breakdown of symmetry (1,1) ground ParaI = 1/2 J OrthoI = 3/2 (3,3)metastable T ~ 250 K 8 hrs Metastable (3,3) 16 hrs (2,2) unstable n ≤ 100 cm-3 (2,2) 361 K 20.4 days (1,0) 27.2 days CO J = 1 (1,1) K Pan and Oka, 1987, ApJ, 305, 518 Oka, Geballe, Goto, Usuda, McCall, 2005, ApJ, 632, 882

Breaking Symmetry The 2 band of H3+ μ 2 = 2521 cm1 = 0.158 D J R(1,0) R(3,3)l R(1,1)l R(2,2)l (3,3) (2,2) (1,0) (1,1) K Oka, Phys. Rev. Lett. 45, 531 (1980)

Telescopes and spectrometers Telescope D Spectrom. λ/Δλ UKIRT 3.8 m CGS4 40,000 Mauna Kea 1982 Subaru8.2 m IRCS 20,000Mauna Kea 2000 Gemini South 8 m Phoenix 60,000Cerro Pachon 2003 VLT 8.2 m CRIRES 100,000 Cerro Paranal 2006 Gemini North 8 m GENIRS 18,000 Mauna Kea 2011 Gemini North Gemini South Subaru UKIRT VLT

CMZ

Super-massive clusters Quintuplet Cluster GCS 3-2 1° × 1° 140 pc × 140 pc

H3+ near the GC Surprises 30 pc UKIRT Huge column density; rich profile Geballe et al. ApJ 1999 Subaru(3,3) metastable and (2,2) unstable H3+ Goto et al. PASJ 2002 Thermalization model analysis Oka & Epp ApJ 2004 Gem. S Revelation of warm and diffuse gas Oka et al. ApJ 2005 Review Oka PNAS 2006 Subaru From the center to 30 pc east Goto et al. ApJ 2008 VLT Scrutiny of the Central core Goto et al. 2010 Gem. S Synthesis Oka et al. 2011

7.3 ×10-8 cm3/s 1.6 ×10-4 1 (1.8-6.1) ×1015 cm-2 3 Simple chemistry of H3+ ζ ProductionH2→H2+ + e H2++H2 →H + H3+ dn(H3+)/dt = ζn(H2) = ken(H3+)n(e) DestructionH3+ + e → H + H + H McCall et al. Phys. Rev. A (2004) ζL = 2 keN(H3+) (nC/nH)SV RX / f (ζL)min = (1.3 – 4.3) ×105 cm/s ζ L 10-16 (0.4 – 1.4) kpc 10-1540 - 140 pc Goto, Usuda, Nagata, Geballe, Indriolo, McCall, Suto, Henning, Morong, and Oka, ApJ, 668, 306 (2008)

Previous concept of gas in the CMZ need to be drastically changed f: 0.8 107-8 K 0.1 104-6 K 10 cm-3 Lazio & Cordes, ApJ, 505, 715 (1998) 0.1 50 K 104 cm-3 Warm and diffuse gas >0.2 250 K102 cm-3

X-ray: Chandra comes to rescue Chandra 20 pc × 20 pc (0.5 – 8) keV Muno et al. ApJ 589, 225 (2003) Warwick, Sakano Decourchelle (2006) Revnivtsev et al. (2006)

Opening a New Vista CMZ

Search for bright and hot stars in the CMZ GLIMPSE 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 bands Skrutskie et al. 2006, AJ, 131, 1163 Star LJ – KK – L (J – K)/(K – L) GCS3-2 3.03 7.33 3.16 2.32 GCS4 3.71 7.65 3.45 2.22 NHS21 4.62 7.03 2.76 2.55* NHS25 6.24 4.81*1.27*3.79* ~ 2,000,000 stars 8 brightness L < 7.5 ~ 3,000 stars youth J - K > 5 K - L > 1.5 (J –K)/(K – L)< 2.5 ~ 300 stars 83 stars so far hotness Low res. CO first overtone, 2.2 – 2.4μm Candidate stars 10 new stars and 5 known stars location High res. H3+ and CO spectroscopy Selected stars

New bright and hot dust embedded stars suitable for H3+ spectroscopy Geballe and Oka, ApJ, 709, L70-73 (2010)

Two sightlines with remarkable H3+ spectrum Quintuplet,α, ι 0 – 30 pc East α ι Geballe and Oka, ApJ, 709, L70-73 (2010)

Iota, the Monster “iota”, 85 pc East, Sgr B (2,2) Low n High T (3,3) Subaru May 4, 2010 Geballe and Oka, ApJ 709, L70-73 (2010)

Remarkable similarity between velocity profiles of 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. Zaal21 3 kpc Scutum Sgittarius H2O+ 110← 101 H3+ R(1,1)l H2O+ 111← 000 A&A June 22 2010 E. Falgarone et al. 2010 Geballe & Oka, 2010, ApJ, 709, L70 17 pc

????? HCl+ H2Cl+ HCl Cl− 1 - 10 H2+ H3+ Dariusz Lis H2 H− 107 H2O+ H3O+ H2O ~ 3.3 OH− Floris van der Tak

http://www.dn.se/nyheter/vetenskap/the-frontrunners-of-the-nobel-prize-2010-1.1181788http://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.

H 3 + in the Central Molecular Zone of the Galactic Center: Revelation of a New Category of Gas