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Multimessenger PerspectivesMultimessenger PerspectivesTeV Particle Astrophysics 2009, Menlo Park, CA, July 15, 2009
Eun-Suk Seo
IPST and Dept. of Phys.University of Maryland
SOURCESInterstellar
medium ChandraSNRs, shocksSuperbubbles
photon emission
X, γe-
P e-γ
Synchrotron
Inverse ComptonBr
acceleration PHe
C, N, O etc.Z = 1- 92
γ
gas
P
Inverse Compton
Bremstrahlung
+
CGROEnergy lossesReacceleration
DiffusionConvection
PHe
C, N, O etc. gasHalo
Disk: sources, gas B
oπ+π −πe+e-
Voyagerγ
Exotic Sources:Antimatter
pescape
BBe
10Be ACE
ATIC
AntimatterDark matter etc..
AMSBESS
ATIC
CREAM
Cosmic Ray Propagation
Consider propagation of CR in the interstellar medium with random hydromagnetic waves.
Steady State Transport Eq.:⎤⎡
∑<
+=⎥⎥⎦
⎤
⎢⎢⎣
⎡⎟⎠⎞
⎜⎝⎛
∂∂
+∂
∂
∂∂
++∂
∂
∂∂
∂jk
jkjjionj
jjj
jj Sqf
dtdpp
pppf
Kppp
fvmz
fD
z ,
22
22
11σρ
The momentum distribution function f is normalized as where N is CR number density, D: spatial diffusion coefficient, σ: cross
section…
fpdpN ∫= 2
{ } kjk
jkjj
ionjj
j
e
j Im
QI
dxdE
dEdI
mXI
∑<
+=⎥⎥⎦
⎤
⎢⎢⎣
⎡⎟⎠⎞
⎜⎝⎛+++
σρ
ασ
0
...
Cosmic ray intensityEscape length XeReacceleration parameter α
jkionje <⎥⎦⎢⎣ ⎠⎝ ρ0,
)()( 02 pfpAEI jjj =
CREAM Eun-Suk Seo 3
Reacceleration parameter αE. S. Seo and V. S. Ptuskin, Astrophys. J., 431, 705-714, 1994.
Cosmic Ray Energetics And Mass (CREAM)
TCDTCDTCD
Upper TRD
Lower TRD
Cherenkov
Upper TRD
Lower TRD
Cherenkov
Upper TRD
Lower TRD
Cherenkov
Calorimeter
Lower TRD
SCD S0/S1Target 1Target 2
Calorimeter
Lower TRD
SCD S0/S1Target 1
Calorimeter
Lower TRD
SCD S0/S1Target 1Target 2
CommandDataM d l
CommandDataM d l
CommandDataM d lModuleModuleModule
H. S. Ahn et al., NIM A, 579, 1034-1053, 2007; Seo et al, Adv. Space Res. 42, 1656-1663, 2008
CREAM 4Eun-Suk Seo
Four successful flights: ~119 days cumulative exposure
CREAM-I12/16/04 – 1/27/05
Record breaking 42 days
CREAM-II12/16/05-1/13/06
28 d
CREAM-III12/19/07-1/17/08
29 d
CREAM-IV12/19/08 – 1/7/09
19 days 13 hrsRecord breaking 42 days 28 days 29 days 19 days 13 hrs
Many thanks to CSBF, WFF, NSF & RPSC for a great campaign!
CREAM 5Eun-Suk Seo
Charge MeasurementsAhn et al, Nucl. Instr. and Meth. A , 602, 525, 2009; Park et al., Nucl. Instr. Meth. A, 581, 133-135, 2007
TCD
SCD
Si
Fe
σ ~ 0 2e p HeC
ONNe
MgSi
CREAM Eun-Suk Seo 6
σz 0.2e p
Calorimeter data for > 3 decades in energySeo 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
1014 eV
1015 eV
CREAM 7Eun-Suk Seo
What is the history of cosmic rays in the Galaxy?Ahn et al. Astropart. Phys., 30/3, 133-141, 2008
• Measurements of the relative abundances of secondary cosmic rays (e g secondary cosmic rays (e.g., B/C) in addition to the energy spectra of primary nuclei will allow determination of cosmic-ray 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
d lmodelsδ−∝RXe
CREAM Eun-Suk Seo 8
Elemental e e aSpectra
CREAM Eun-Suk Seo 9
P & He: prior to CREAM
γ−∝EI ∝EIj
JACEE J CγP = 2.80 ± 0.04γHe = 2.68+0.04-0.06
ATIC2γ = 2 63 ± 0 01AMS
RUNJOBγP = 2.78 ± 0.05
(2.74 ± 0.08) γ = 2 81 ± 0 06γP = 2.63 ± 0.01
γHe = 2.58 ± 0.01γP = 2.78 ± 0.009γHe = 2.74 ± 0.01
γHe = 2.81 ± 0.06(2.78 ± 0.2)
CREAM Eun-Suk Seo 10
CREAM: p & He spectra are not the sameOur fluxes are significantly higher than the extrapolation of a single-power law fit to the l
Unpublished Data low energy spectra
Different types of
Not shownDifferent types of sources or acceleration mechanisms? (e g mechanisms? (e.g., Biermann, P. L. A&A 271, 649,1993)
CREAM Eun-Suk Seo 11
TeV spectra are harder than spectra <100 GeV/n Departure from a single power law caused by cosmic ray interactions
ith th sh ck?with the shock?(e.g., Ellison et al. ApJ540, 292, 2000)Unpublished Data The reported flattening of the synchrotron spectrum of SN1006 indicated spectral curvature which
Not shownspectral curvature, which provides evidence that cosmic rays are dynamically important (Allen et al. ApJ683/2,773, 2008).
CREAM Eun-Suk Seo 12
Heavies look like He
Unpublished Data Not shown
CREAM Eun-Suk Seo 13
Electrons: the same valley?
Chang et al. Nature, 456. 362, 2008
Abdo et al. PRL, 102, 181101, 2009
If so is a single mechanism responsible for all the If so, is a single mechanism responsible for all the elements, as well as electrons?
CREAM Eun-Suk Seo 14
Results & Implications
• Spectral difference between p and He– Are there different types of sources or acceleration mechanisms? 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? 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)f ff f l d f h l – 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, 221101, 2008)?221101, 2008)?Related to the electron excess reported by ATIC?
CREAM Eun-Suk Seo 15
Refurbish CREAM-III (IV) for CREAM-V (VI) integrationCREAM-V Launch is planned for December 2009
CREAM Eun-Suk Seo 16
A step closer to ULDB
Successful SPB Test Flight
7 MCF At FloatThe super pressure balloon’s altitude stability
CREAM-IV
ANITA-II
SPB
CREAM Eun-Suk Seo 17
54 days (12/28/08 – 2/20/09)
http://cosmicray.umd.edu/creamCREAM Collaboration
http //cosm cray.um . u/cr am
E. S. Seoa,b, H. S. Ahn a, P. Allisonc, T. Andersond, M.G. Bagliesie, L. Barbierf, A. Barraug, R. Bazer-Bachig, J. J. Beatty c, G. Bigongiarie, P. Bhoyar a, P. Boyleh, T. T Brandt c M Buénerdg N B Conklind S Coutud L Deromeg M A DuVernois j T. Brandt , M. Buénerdg, N. B. Conklin , S. Coutu , L. Deromeg, M. A. DuVernois j, O. Ganela, M. Gesked, J. H. Hana, J. A. Jeonk, K. C. Kima, M. H. Leea, J. Linkf, L. Lutza, A. Malinina, M. Mangin-Brinet g, P. S. Marrocchesie, P. Maestroe, A. Menchaca-Rochal, J. W. Mitchellf, S. I. Mognet e, G. Nak, S. Namk, S. Nutterm, I. H. Parkk, N. H. Parkk, J. N. Périég , A. Putzg, Y. Sallaz-Damazg, S. Swordyh, S.
h k by
Wakelyh, P. Walpolea, J. Wua, J. Yangk, Y. S. Yoonb, R. Zeie, and S. Y. Zinna
aInst. for Phys. Sci. and Tech., University of Maryland, College Park, MD 20742, USAbDept. of Physics, University of Maryland, College Park, MD 20742, USA
cDept of Physics Ohio State University Columbus Ohio 43210 USADept. of Physics, Ohio State University, Columbus, Ohio 43210, USAdDept. of Physics, Penn State University, University Park, PA 16802, USA
eDept. of Physics, University of Siena and INFN, Via Roma 56, 53100 Siena, ItalyfNASA Goddard Space Flight Center, Greenbelt, MD 20771, USA
gLaboratorire de Physique Subatomique et de Cosmologie, Grenoble, FrancehE i F i I i d D f Ph i U i i f Chi Chi IL 60637 USAhEnrico Fermi Institute and Dept. of Physics, University of Chicago, Chicago, IL 60637, USAiCentre d’Etude Spatiale des Rayonnements, UFR PCA - CNRS - UPR 8002, Toulouse, France
jSchool of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455, USAkDept. of Physics, Ewha Womans University, Seoul, 120-750, Republic of Korea
lInstituto de Fisica, Universidad Nacional Autonoma de Mexico, Mexico
CREAM Eun-Suk Seo 18
Instituto de Fisica, Universidad Nacional Autonoma de Mexico, MexicomDept. of Physics and Geology, Northern Kentucky University, Highland Heights, KY 41099,
USA
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