TeV Particle Astrophysics 2009, Menlo Park, CA, July 15, Eun-Suk Seo. IPST and Dept. of Phys. University of Maryland

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1 Multimessenger Perspectives TeV Particle Astrophysics 2009, Menlo Park, CA, July 15, 2009 Eun-Suk Seo IPST and Dept. of Phys. University of Maryland

2 SOURCES SNRs, shocks Superbubbles photon emission acceleration Halo Exotic Sources: Disk: sources, gas Antimatter Dark matter etc.. escape X, γ e - Interstellar medium P e - B r γ P He C, N, O etc. Z = 1-92 Energy losses Reacceleration Diffusion Convection P He C, N, O etc. gas gas e + e - o + π π p π Synchrotron Inverse Compton Bremstrahlung γ Chandra CGRO Voyager B Be 10 Be ACE ATIC BESS AMS CREAM

3 Cosmic Ray Propagation Consider propagation of CR in the interstellar medium with random hydromagnetic waves. Steady State Transport Eq.: f ρ + vσf j m 1 p f p p dp dt j 2 j 2 Dj + p Kj z z p p p j, ion 1 f j = q The momentum distribution function f is normalized as where N is CR number density, D: spatial diffusion coefficient, σ: cross section I X σ d de j + k< j S jk N = dpp j jk {}... + I j = + Ik j j + I j + α e m de dx j, ion ρ 0 k < j 2 I j ( E) = Aj p f0 j( p) Cosmic ray intensity Escape length Xe Reacceleration parameter α Q E. S. Seo and V. S. Ptuskin, Astrophys. J., 431, , CREAM Eun-Suk Seo 3 σ m 2 f

4 Cosmic Ray Energetics And Mass (CREAM) TCD Upper TRD Cherenkov Lower TRD SCD Target 1 Target 2 Calorimeter S0/S1 Command Data Module H. S. Ahn et al., NIM A, 579, , 2007; Seo et al, Adv. Space Res. 42, , 2008 CREAM Eun-Suk Seo 4

5 Four successful flights: ~119 days cumulative exposure CREAM-I CREAM-II CREAM-III CREAM-IV 12/16/04 1/27/05 12/16/05-1/13/06 12/19/07-1/17/08 12/19/08 1/7/09 Record breaking 42 days 28 days 29 days 19 days 13 hrs Many thanks to CSBF, WFF, NSF & RPSC for a great campaign! CREAM Eun-Suk Seo 5

6 Charge Measurements Ahn et al, Nucl. Instr. and Meth. A, 602, 525, 2009; Park et al., Nucl. Instr. Meth. A, 581, , 2007 TCD Fe SCD Si Mg Ne O CN σz ~ 0.2e 0 2e CREAM p Eun-Suk Seo He 6

7 Calorimeter data for > 3 decades in energy Seo et al., Nucl. Phys. B Proc. Suppl. 176, 155, 2008; Seo et al, J. Phys. Soc. Japan, Suppl. A. 78, 63, 2009 Consistent power law for all particle data from 4 flights Lower Energy Threshold for CREAM-III & IV ev ev CREAM Eun-Suk Seo 7

8 What is the history of cosmic rays in the Galaxy? Ahn et al. Astropart. Phys., 30/3, , 2008 Measurements of the relative abundances of secondary cosmic rays (e.g., B/C) in addition to the energy spectra of primary nuclei will allow determination of cosmic-ray source spectra at energies where measurements are not currently available First B/C ratio at these high energies to distinguish among the propagation models X e δ R CREAM Eun-Suk Seo 8

9 Elemental e Spectra CREAM Eun-Suk Seo 9

10 P & He: prior to CREAM γ I j E JACEE γ P = 2.80 ± 0.04 γ He = AMS γ P = 2.78 ± γ He = 2.74 ± 0.01 ATIC2 γ P =263± γ He = 2.58 ± 0.01 RUNJOB γ P = 2.78 ± 0.05 (2.74 ± 0.08) γ He =281± (2.78 ± 0.2) CREAM Eun-Suk Seo 10

11 CREAM: p & He spectra are not the same Unpublished Data Not shown Our fluxes are significantly higher than the extrapolation of a single-power law fit to the low energy spectra Different types of sources or acceleration mechanisms? (e.g., Biermann, P. L. A&A 271, 649,1993) CREAM Eun-Suk Seo 11

12 TeV spectra are harder than spectra <100 GeV/n Unpublished Data Not shown Departure from a single power law caused by cosmic ray interactions with the shock? (e.g., Ellison et al. ApJ 540, 292, 2000) The reported flattening of the synchrotron spectrum of SN1006 indicated spectral curvature, which provides evidence that cosmic rays are dynamically important (Allen et al. ApJ 683/2,773, 2008). CREAM Eun-Suk Seo 12

13 Heavies look like He Unpublished Data Not shown CREAM Eun-Suk Seo 13

14 Electrons: the same valley? Chang et al. Nature, , 2008 Abdo et al. PRL, 102, , 2009 If so, is a single mechanism responsible for all the elements, as well as electrons? CREAM Eun-Suk Seo 14

15 Results & Implications Spectral difference between p and He Are there different types of sources or acceleration mechanisms? (Biermann, P. L. A&A 271, 649,1993) Flattening of elemental spectra at high energies Evidence for concavity due to cosmic ray interactions with the shock? (Ellison et al. ApJ 540, 292,2000; Allen et al. ApJ 683/2,773, 2008). Indicate source spectra that are harder than previously thought, based on the low energy data? Some propagation effect, such as reacceleration, boosts low energy spectra? Contributions from multi sources (Zatsepin & Sokolskaya, A&A 458, 1, 2006) If not an effect of acceleration or propagation, and if the conventional model is valid, are we seeing a local source of hadrons? Related to 10 TeV anisotropy reported by Milagro (Abdo et al. PRL, 101, , 2008)? Related to the electron excess reported by ATIC? CREAM Eun-Suk Seo 15

16 Refurbish CREAM-III (IV) for CREAM-V (VI) integration CREAM-V Launch is planned for December 2009 CREAM Eun-Suk Seo 16

17 A step closer to ULDB Successful SPB Test Flight 7 MCF At Float The super pressure balloon s altitude stability CREAM-IV ANITA-II SPB 54 days (12/28/08 2/20/09) CREAM Eun-Suk Seo 17

18 CREAM Collaboration cray.um. u/cr am E. S. Seo a,b, H. S. Ahn a, P. Allison c, T. Anderson d, M.G. Bagliesi e, L. Barbier f, A. Barrau g, R. Bazer-Bachi g, J. J. Beatty c,g. Bigongiari e, P. Bhoyar a, P. Boyle h, T. T. Brandt c, M. Buénerd g, N. B. Conklin d, S. Coutu d, L. Derome g, M. A. DuVernois j, O. Ganel a, M. Geske d, J. H. Han a, J. A. Jeon k, K. C. Kim a,m. H. Lee a,j. Link f, L. Lutz a,a. Malinin a, M. Mangin-Brinet g, P. S. Marrocchesi e, P. Maestro e, A. Menchaca-Rocha l, J. W. Mitchell f, S. I. Mognet e, G. Na k,s. Nam k, S. Nutter m,i. H. Park k, N. H. Park k, J. N. Périé g, A. Putz g, Y. Sallaz-Damaz g, S. Swordy h,s. Wakely h, P. Walpole a,j. Wu a, J. Yang k, Y. S. Yoon b, R. Zei e, and S. Y. Zinn a a Inst. for Phys. Sci. and Tech., University of Maryland, College Park, MD 20742, USA b Dept. of Physics, University of Maryland, College Park, MD 20742, USA c Dept. of Physics, Ohio State University, Columbus, Ohio 43210, USA d Dept. of Physics, Penn State University, University Park, PA 16802, USA e Dept. of Physics, University of Siena and INFN, Via Roma 56, Siena, Italy f NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA g Laboratorire de Physique Subatomique et de Cosmologie, Grenoble, France h Enrico Fermi Institute and Dept. of Physics, University i of Chicago, Chicago, IL 60637, USA i Centre d Etude Spatiale des Rayonnements, UFR PCA - CNRS - UPR 8002, Toulouse, France j School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USA k Dept. of Physics, Ewha Womans University, Seoul, , Republic of Korea l Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Mexico m Dept. of Physics and Geology, Northern Kentucky University, Highland Heights, KY 41099, USA CREAM Eun-Suk Seo 18