Igor V. Moskalenko (Stanford U.) Challenges in Astrophysics of CR (knee--) & γ-rays Topics covered:  Intro to the relevant physics  Modeling of the CR propagation and diffuse emission  Perspectives: Pamela, GLAST and other near future missions

Igor V. Moskalenko 2 November 17, 2005Miniworkshop/Rome2, Italy CR Interactions in the Interstellar Medium e + - PHeCNO X,γ gas ISRF e + - π + - P_LiBeB ISM diffusion energy losses energy losses reacceleration reacceleration convection convection etc. etc. π 0 synchrotron IC bremss Chandra GLAST ACE helio-modulation p 42 sigma ( data) HESS Preliminary SNR RX J PSF BHeCNO Flux 20 GeV/n CR species:  Only 1 location  modulation e + - π + - PAMELA BESS AMS

Igor V. Moskalenko 3 November 17, 2005Miniworkshop/Rome2, Italy Elemental Abundances: CR vs. Solar System CR abundances: ACE Solar system abundances LiBeB CNO F Fe ScTiV CrMn Si Cl Al O Volatility Na S Long propagation history…

Igor V. Moskalenko 4 November 17, 2005Miniworkshop/Rome2, Italy Nuclear component in CR: What we can learn? Propagation parameters: Diffusion coeff., halo size, Alfvén speed, convection velosity… Energy markers: Reacceleration, solar modulation Local medium: Local Bubble Material & acceleration sites, nucleosynthesis (r- vs. s-processes) Stable secondaries: Li, Be, B, Sc, Ti, V Radio (t 1/2 ~1 Myr): 10 Be, 26 Al, 36 Cl, 54 Mn K-capture: 37 Ar, 49 V, 51 Cr, 55 Fe, 57 Co Short t 1/2 radio 14 C & heavy Z>30 Heavy Z>30: Cu, Zn, Ga, Ge, Rb Nucleo- synthesis: supernovae, early universe, Big Bang… Solar modulation Diffuse γ-rays Galactic, extragalactic: blazars, relic neutralino Dark Matter (p,đ,e +,γ) -

Igor V. Moskalenko 5 November 17, 2005Miniworkshop/Rome2, Italy Diffuse Galactic Gamma-ray Emission ~80% of total Milky Way luminosity at HE !!! Tracer of CR (p, e − ) interactions in the ISM (π 0,IC,bremss): oStudy of CR species in distant locations (spectra & intensities)  CR acceleration (SNRs, pulsars etc.) and propagation oEmission from local clouds → local CR spectra  CR variations, Solar modulation oMay contain signatures of exotic physics (dark matter etc.)  Cosmology, SUSY, hints for accelerator experiments oBackground for point sources (positions, low latitude sources…) Besides: o“Diffuse” emission from other normal galaxies (M31, LMC, SMC)  Cosmic rays in other galaxies ! oForeground in studies of the extragalactic diffuse emission oExtragalactic diffuse emission (blazars ?) may contain signatures of exotic physics (dark matter, BH evaporation etc.) Calculation requires knowledge of CR (p,e) spectra in the entire Galaxy

Igor V. Moskalenko 6 November 17, 2005Miniworkshop/Rome2, Italy Transport Equations ~90 (no. of CR species) ψ(r,p,t) – ψ(r,p,t) – density per total momentum sources (SNR, nuclear reactions…) convection convection (Galactic wind) diffusion diffusive reacceleration diffusive reacceleration (diffusion in the momentum space) E-loss fragmentation radioactive decay + boundary conditions

Igor V. Moskalenko 7 November 17, 2005Miniworkshop/Rome2, Italy CR Propagation: Milky Way Galaxy Halo Gas, sources 100 pc 40 kpc 4-12 kpc /ccm 1-100/ccm Intergalactic space 1 kpc ~ 3x10 18 cm R Band image of NGC GHz continuum (NVSS), 1,2,…64 mJy/ beam Optical image: Cheng et al. 1992, Brinkman et al Radio contours: Condon et al AJ 115, 1693 NGC891 Sun “Flat halo” model (Ginzburg & Ptuskin 1976)

Igor V. Moskalenko 8 November 17, 2005Miniworkshop/Rome2, Italy A Model of CR Propagation in the Galaxy  Gas distribution (energy losses, π 0, brems)  Interstellar radiation field (IC, e ± energy losses)  Nuclear & particle production cross sections  Gamma-ray production: brems, IC, π 0  Energy losses: ionization, Coulomb, brems, IC, synch  Solve transport equations for all CR species  Fix propagation parameters  “Precise” Astrophysics

Igor V. Moskalenko 9 November 17, 2005Miniworkshop/Rome2, Italy Wherever you look, the GeV  -ray excess is there ! 4a-f EGRET data

Igor V. Moskalenko 10 November 17, 2005Miniworkshop/Rome2, Italy Reacceleration Model vs. Plain Diffusion Plain Diffusion (D xx ~β -3 R 0.6 ) Diffusive Reacceleration B/C ratio Antiproton flux B/C ratio

Igor V. Moskalenko 11 November 17, 2005Miniworkshop/Rome2, Italy Positron Excess ?  Are all the excesses connected somehow ?  A signature of a new physics (DM) ? Caveats:  Systematic errors ?  A local source of primary positrons ?  Large E-losses -> local spectrum… HEAT (Beatty et al. 2004) GALPROP 1 E, GeV 10 e + /e HEAT 2000 HEAT HEAT combined 1 E, GeV 10 Q: Are all the excesses connected? A: “Yes” and “No” Same progenitor (CR p or DM) for pbars, e + ’s, γ’s Systematic errors of different detectors E > 6 GeV

Igor V. Moskalenko 12 November 17, 2005Miniworkshop/Rome2, Italy CR Source Distribution SNR source The CR source (SNRs, pulsars) distribution is too narrow to match the CR distribution in the Galaxy assuming X CO =N(H 2 )/W CO =const (CO is a tracer of H 2 ) Lorimer 2004 Pulsars CR after propagation diffuse γ-ray distribution

Igor V. Moskalenko 13 November 17, 2005Miniworkshop/Rome2, Italy Injection into the ISM Life and death of e + Energy loss Positronium In flight Direct annihilation with bound electrons Radiative Capture Grains Charge Exchange 22 22 22 33 Direct annihilation with free electrons Positronium Thermalisation All sky view of 511 keV emission Knödlseder et al 2005 Positron Annihilation Line W.Gillard INTEGRAL-SPI

Igor V. Moskalenko 14 November 17, 2005Miniworkshop/Rome2, Italy Hypotheses… Provide good agreement with all data (diffuse gammas, pbars, e+)  CR intensity variations  Dark Matter signals Other possibilities: Harder CR spectrum (protons, electrons) – deviates limits from pbars, gamma-ray profiles Influence of the Local Bubble (local component) – helps with pbars, but doesn’t help with diffuse gammas

Igor V. Moskalenko 15 November 17, 2005Miniworkshop/Rome2, Italy Diffuse emission models GeV >0.5 GeV Dark Matter Cosmic Ray Spectral Variations EGRET “GeV Excess” There are two possible BUT fundamentally different explanations of the excess, in terms of exotic and traditional physics:  Dark Matter  CR spectral variations Both have their pros & cons. from Strong et al. ApJ (2004) from de Boer et al. A&A (2005) from Hunter et al. ApJ (1997)

Igor V. Moskalenko 16 November 17, 2005Miniworkshop/Rome2, Italy CR Variations in Space & Time More frequent SN in the spiral arms Historical variations of CR intensity: ~40kyr ( 10 Be in South Polar ice), ~2.8Myr ( 60 Fe in deep sea FeMn crust) Konstantinov et al Electron/positron energy losses Different “collecting” areas A vs. p (σ~30 mb) (different sources ?) SNR number density R, kpc

Igor V. Moskalenko 17 November 17, 2005Miniworkshop/Rome2, Italy Electron Fluctuations/SNR stochastic events GeV electrons 100 TeV electrons GALPROP/Credit S.Swordy Energy losses 10 7 yr 10 6 yr Bremsstrahlung 1 TeV Ionization Coulomb IC, synchrotron 1 GeV Ekin, GeV E(dE/dt) -1,yr Electron energy loss timescale: 1 TeV: ~300 kyr 100 TeV: ~3 kyr

Igor V. Moskalenko 18 November 17, 2005Miniworkshop/Rome2, Italy GeV excess: Optimized/Reaccleration model Uses all sky and antiprotons & gammas to fix the nucleon and electron spectra  Uses antiprotons to fix the intensity of CR HE  Uses gammas to adjust  the nucleon spectrum at LE  the intensity of the CR electrons (uses also synchrotron index)  Uses EGRET data up to 100 GeV protons electrons x4 x1.8 antiprotons E k, GeV

Igor V. Moskalenko 19 November 17, 2005Miniworkshop/Rome2, Italy Secondary e ± are seen in γ-rays ! Lots of new effects ! Improves an agreement at LE brems IC Heliosphere: e + /e~0.2 electrons positrons sec.

Igor V. Moskalenko 20 November 17, 2005Miniworkshop/Rome2, Italy Diffuse Gammas at Different Sky Regions Intermediate latitudes: l=0°-360°,10°<|b|<20° Outer Galaxy: l=90°-270°,|b|<10° Intermediate latitudes: l=0°-360°,20°<|b|<60° Inner Galaxy: l=330°-30°,|b|<5° Hunter et al. region: l=300°-60°,|b|<10° l=40°-100°,|b|<5° corrected Milagro

Igor V. Moskalenko 21 November 17, 2005Miniworkshop/Rome2, Italy Longitude Profiles |b|<5° MeV 2-4 GeV GeV 4-10 GeV

Igor V. Moskalenko 22 November 17, 2005Miniworkshop/Rome2, Italy Latitude Profiles: Inner Galaxy MeV 2-4 GeV0.5-1 GeV 4-10 GeV20-50 GeV

Igor V. Moskalenko 23 November 17, 2005Miniworkshop/Rome2, Italy Latitude Profiles: Outer Galaxy MeV 2-4 GeV GeV 4-10 GeV

Igor V. Moskalenko 24 November 17, 2005Miniworkshop/Rome2, Italy Anisotropic Inverse Compton Scattering  Electrons in the halo see anisotropic radiation  Observer sees mostly head-on collisions e-e- e-e- head-on: large boost & more collisions γ γ small boost & less collisions γ sun Energy density Z, kpc R=4 kpc high latitudes !

Igor V. Moskalenko 25 November 17, 2005Miniworkshop/Rome2, Italy Extragalactic Gamma-Ray Background Predicted vs. observed E, MeV E 2 xF Sreekumar et al Strong et al Elsaesser & Mannheim, astro-ph/ Blazars Cosmological neutralinos EGRB in different directions

Igor V. Moskalenko 26 November 17, 2005Miniworkshop/Rome2, Italy Distribution of CR Sources & Gradient in the CO/H 2 CR distribution from diffuse gammas (Strong & Mattox 1996) SNR distribution (Case & Bhattacharya 1998) sun X CO =N(H 2 )/W CO : Histo –This work, Strong et al.’ Sodroski et al.’95,’97 1.9x Strong & Mattox’96 ~Z -1 – Boselli et al.’02 ~Z Israel’97,’00, [O/H]=0.04,0.07 dex/kpc Pulsar distribution Lorimer 2004

Igor V. Moskalenko 27 November 17, 2005Miniworkshop/Rome2, Italy Again Diffuse Galactic Gamma Rays More IC in the GC – better agreement ! The pulsar distribution vs. R falls too fast OR larger H 2 /CO gradient Very good agreement ! 2-4 GeV

Igor V. Moskalenko 28 November 17, 2005Miniworkshop/Rome2, Italy E.Bloom’05

Igor V. Moskalenko 29 November 17, 2005Miniworkshop/Rome2, Italy Matter, Dark Matter, Dark Energy… Ω ≡ ρ/ρ crit Ω tot =1.02 +/−0.02 Ω Matter =4.4%+/−0.4% Ω DM =23% +/−4% Ω Vacuum =73% +/−4% “Supersymmetry is a mathematically beautiful theory, and would give rise to a very predictive scenario, if it is not broken in an unknown way which unfortunately introduces a large number of unknown parameters…” Lars Bergström (2000) SUSY DM candidate has also other reasons to exist -particle physics…

Igor V. Moskalenko 30 November 17, 2005Miniworkshop/Rome2, Italy Where is the DM ?! Flavors:  Neutrinos ~ visible matter  Super-heavy relics: “wimpzillas”  Axions  Topological objects “Q-balls” Neutralino-like, KK-like Places: Galactic halo, Galactic center  The sun and the Earth Tools:  Direct searches –low-background experiments (DAMA, EDELWEISS) –neutrino detectors (AMANDA/IceCUBE) –Accelerators (LHC) Indirect searches –CR, γ’s (PAMELA,GLAST,BESS) from E.Bloom presentation

Igor V. Moskalenko 31 November 17, 2005Miniworkshop/Rome2, Italy Example “Global Fit:” diffuse γ’s, pbars, positrons  Look at the combined (pbar,e +,γ) data  Possibility of a successful “global fit” can not be excluded -non-trivial ! pbars e+e+ γ GALPROP/W. de Boer et al. hep-ph/ Supersymmetry:  MSSM (DarkSUSY)  Lightest neutralino χ 0  m χ ≈ GeV  S=½ Majorana particles  χ 0 χ 0 −> p, pbar, e +, e −, γ

Igor V. Moskalenko 32 November 17, 2005Miniworkshop/Rome2, Italy Longitude and Latitude Distr. E >0.5 GeV In the plane (± 5 0 in lat.) Out of the plane (± 30 0 in long.. )

Igor V. Moskalenko 33 November 17, 2005Miniworkshop/Rome2, Italy x y z 2003, Ibata et al, Yanny et al. Outer Ring Inner Ring DM halo disk bulge Rotation Curve xy xz xy xz Expected Profile (NFW) Halo profile Isothermal Profile v 2  M/r=cons. and  M/r 3  1/r 2 for const. rotation curve Observed Profile: EGRET data + GALPROP Executive Summary –de Boer et al. astro-ph/

Page Number PAMELA: Secondary to Primary ratios plots: M.Simon  LE: sec/prim peak: one instrument -no cross calibration errors  HE: D xx (R)

Igor V. Moskalenko 35 November 17, 2005Miniworkshop/Rome2, Italy PAMELA positrons  A factor of 2 will become statistically significant  Measuring absolute flux not ratio  Solar minimum conditions After 3 years

Igor V. Moskalenko 36 November 17, 2005Miniworkshop/Rome2, Italy PAMELA antiprotons After 3 years

Igor V. Moskalenko 37 November 17, 2005Miniworkshop/Rome2, Italy DM in Diffuse γ-rays: Spectral Signature Ullio et al.2002 Smoking gun! GLAST LAT

Igor V. Moskalenko 38 November 17, 2005Miniworkshop/Rome2, Italy Pohl et al.2003 sun Positions of the local clouds The Excess: Clues from the Local Medium Digel et al.2001 Observations of the local medium in different directions, e.g. local clouds, will provide a clue to the origin of the excess (assuming it exists). Inconclusive based on EGRET data YesNo Poor knowledge of π 0 -production cross section: better understanding of π 0 -production Dark Matter signal: look for spectral signatures in cosmic rays (PAMELA, BESS, AMS) and in collider experiments (LHC) Possibility: cosmic-ray spectral variations. Further test: look at more distant clouds Will GLAST see the excess? EGRET data

Igor V. Moskalenko 39 November 17, 2005Miniworkshop/Rome2, Italy

Igor V. Moskalenko 40 November 17, 2005Miniworkshop/Rome2, Italy σ σ

Igor V. Moskalenko 41 November 17, 2005Miniworkshop/Rome2, Italy A.Morselli

Igor V. Moskalenko 42 November 17, 2005Miniworkshop/Rome2, Italy GLAST LAT simulations EGRET intensity (>100 MeV) LAT simulation (>100 MeV) |b| < 20° Seth Digel

Igor V. Moskalenko 43 November 17, 2005Miniworkshop/Rome2, Italy GLAST LAT: The Gamma-Ray Sky EGRET (>100 MeV) Simulated LAT (>100 MeV, 1 yr) Simulated LAT (>1 GeV, 1 yr) This is an animation that steps from 1. EGRET (>100 MeV), to 2. LAT (>100 MeV), to 3. LAT (>1 GeV) Seth Digel

Igor V. Moskalenko 44 November 17, 2005Miniworkshop/Rome2, Italy Conclusions I Accurate measurements of nuclear species in CR, secondary positrons, antiprotons, and diffuse γ-rays simultaneously may provide a new vital information for Astrophysics – in broad sense, Particle Physics, and Cosmology. Gamma rays: GLAST is scheduled to launch in 2007 – diffuse gamma rays is one of its priority goals CR species: New measurements at LE & HE simultaneously (PAMELA, Super-TIGER, AMS…) Hunter et al. region: l=300°-60°,|b|<10° Dark Matter Z h increase Be 10 /Be 9 E k, MeV/nucleon B/C E k, MeV/nucleon

Igor V. Moskalenko 45 November 17, 2005Miniworkshop/Rome2, Italy Conclusions II Antiprotons: PAMELA (2006), AMS (2008) and a new BESS- polar instrument to fly a long- duration balloon mission (in 2004, 2006…), we thus will have more accurate and restrictive antiproton data HE electrons: Several missions are planned to target specifically HE electrons In few years we may expect major breakthroughs in Astrophysics and Particle Physics ! CERN Large Hadronic Collider – will address SUSY Positrons: PAMELA (2006), AMS (2008): accurate and restrictive positron data

Igor V. Moskalenko 46 November 17, 2005Miniworkshop/Rome2, Italy Thank you !