GLAST and NANTEN Molecular clouds as a probe of high energy phenomena Yasuo Fukui Nagoya University May 22, 2007 UCLA

NANTEN & Campanas, alt.2400m

Galactic Plane Survey 12 CO(J=1-0), Grid size ~ 4 (|b|<5  ), 8 (5  <|b|<10  ) Integ. time (typ) ~5sec/point, 1,100,000 observed points

POINTS Cosmic ray protons: identify the sites of acceleration by establishing the hadoronic origin of gamma rays X factor = H2/W(CO) is determined GLAST offers a useful tool with NANTEN CO dataset

We are having brand-new samples of VHE gamma-ray sources & dense cloud complexes in our Galaxy. CR accelerators and acceleration process: - SNR, PWN, XRB, UID…. Comparisons of TeV Gamma-rays with molecular data will give us information of - distance - environment - circumstance ISM distribution - CR acceleration efficiency?

Need for Molecular Observations of SNRs ■ Samples of SNR-dense cloud interaction → still poor ■ Observations of γ-rays from CR accelerated in SNRs → angular resolution becoming higher ■ Distances of many Galactic SNRs → still unknown γ-ray…. ・ cannot provide direct information on distance. X-ray …. ・ can estimate absorption N(H) → distance Molecular lines… ・ spatial / velocity distribution of dense clouds ・ kinematic distance ・ column density toward SNRs ( ⇔ X-ray) ・ search for shocked dense gas

Molecular clouds toward GC TeV ridge - NANTEN 13CO(J=1-0), velocity channel maps (increment: 10km/s)

Galactic Center Molecular Loop2 Fukui,Y. et al. Science, 314, 106, 2006

12 CO(J=1-0) and X-ray in G Fukui et al molecular hole surrounding boundary of the SNR CO peaks ⇔ X-ray peaks show good spatial correlation (northwestern bright rim) ↓ indicates interaction of the SNR with molecular clouds. -11 km/s < V LSR < -3 km/s Ｄ Ａ B C

G Velocity distribution

V LSR and kinematic distance

Parametersd = 1 kpc d = 6 kpc Radius (pc) Age (yr)1600>10000 Evolutionary phaseFree-expSedov Ambient density (cm -3 )< Shock velocity (km/s) E total of accelerated particles * (erg) ~ ~ * (E acc /10 48 )(M cloud /200)(l/3) -3 (d/1) -5 = 1.35 (Enomoto et al.2002) Physical parameters of G

XMM and NANTEN Moriguchi et al. 2005

ASTE CO J=3- 2

TeV-gamma & molecular clouds H.E.S.S. image (Aharonian et al. 2004) 17 pc

SNR G (RSJ ) -Shell-like structure: similar with X-rays - No significant variation of spectrum index across the regions -spatial correlation with surrounding molecular gas Aharonian et al. 2005

SNR G (RX J , Vela Jr.) Molecular observations (Moriguchi et al. 2001) Age: several x 1000 yr ? Distance: kpc ? 44 Ti line Detection by COMPTEL (Iyudin et al. 1998)

Concentration of Masers nerby SNR Association with UCHII: W28A2 Hotspots around SNR 2-3 % Size ~ deg Spectra: dN/DE ~ E H.E.S.S. detection toward W28 [Preliminary]

HESS Molecular clouds associated with counterparts of TeV sources - HII region W33, SNR (AXJ ) - distance ~ 4 kpc -> consistent with kinematic dist

HLC Survey toward far-infrared excess clouds 32 HLCs are newly detected Onishi et al. 2005

Per shell of HLC Yamamoto,et al. ApJ, in press, 2006

ASTE CO J=3- 2

12 CO(J=3-2) wing-like profiles

12 CO(J=1-0) wing-like profiles

LVG analysis Large Velocity Gradient model (e.g. Goldreich & Kwan 1974, Kim et al. 2002) One-dimensional uniform velocity gradient. gradV = 5 km/s X(CO) = R(3-2)/(1-0) ~ ↓ n(H 2 ) ~ cm -3 T kin ~ K For typical dark clouds n(H 2 ) ~ cm -3, T kin ~ K

POINTS Cosmic ray protons: identify the sites of acceleration by establishing the hadoronic origin of gamma rays X factor = H2/W(CO) is determined GLAST offers a useful tool with NANTEN CO dataset