Antimatter from Supernova Remnants Michael Kachelrieß NTNU, Trondheim with S. Ostapchenko, R. Tom` as
PAMELA anomaly )) 0.4 - (e φ 0.3 )+ + (e 0.2 φ ) / ( + (e φ Positron fraction 0.1 Muller & Tang 1987 MASS 1989 TS93 HEAT94+95 CAPRICE94 AMS98 HEAT00 0.02 Clem & Evenson 2007 PAMELA 0.01 0.1 1 10 100 Energy (GeV) Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 2 / 18
Astrophysical sources for anti-matter: CR secondaries standard secenario for Galactic CRs: ◮ sources are SNRs: kinetic energy output of SNe: 10 M ⊙ ejected with v ∼ 5 × 10 8 cm/s every 30 yr ⇒ L SN , kin ∼ 3 × 10 42 erg/s ◮ explains local energy density of CR ǫ CR ∼ 1 eV/cm 3 for a escape time from disc τ esc ∼ 6 × 10 6 yr Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 3 / 18
Astrophysical sources for anti-matter: CR secondaries standard secenario for Galactic CRs: ◮ sources are SNRs: kinetic energy output of SNe: 10 M ⊙ ejected with v ∼ 5 × 10 8 cm/s every 30 yr ⇒ L SN , kin ∼ 3 × 10 42 erg/s ◮ explains local energy density of CR ǫ CR ∼ 1 eV/cm 3 for a escape time from disc τ esc ∼ 6 × 10 6 yr ◮ 1.order Fermi shock acceleration ⇒ dN/dE ∝ E − γ with γ = 2 . 0 − 2 . 2 ◮ diffusion with D ( E ) ∝ τ esc ( E ) ∼ E − δ and δ ∼ 0 . 5 explains observed spectrum E − 2 . 6 Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 3 / 18
Astrophysical sources for anti-matter: CR secondaries standard secenario for Galactic CRs: ◮ sources are SNRs: kinetic energy output of SNe: 10 M ⊙ ejected with v ∼ 5 × 10 8 cm/s every 30 yr ⇒ L SN , kin ∼ 3 × 10 42 erg/s ◮ explains local energy density of CR ǫ CR ∼ 1 eV/cm 3 for a escape time from disc τ esc ∼ 6 × 10 6 yr ◮ 1.order Fermi shock acceleration ⇒ dN/dE ∝ E − γ with γ = 2 . 0 − 2 . 2 ◮ diffusion with D ( E ) ∝ τ esc ( E ) ∼ E − δ and δ ∼ 0 . 5 explains observed spectrum E − 2 . 6 electrons, positrons: τ loss ≪ τ esc and τ loss ∝ 1 /E Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 3 / 18
Astrophysical sources for anti-matter: CR secondaries standard secenario for Galactic CRs: ◮ sources are SNRs: kinetic energy output of SNe: 10 M ⊙ ejected with v ∼ 5 × 10 8 cm/s every 30 yr ⇒ L SN , kin ∼ 3 × 10 42 erg/s ◮ explains local energy density of CR ǫ CR ∼ 1 eV/cm 3 for a escape time from disc τ esc ∼ 6 × 10 6 yr ◮ 1.order Fermi shock acceleration ⇒ dN/dE ∝ E − γ with γ = 2 . 0 − 2 . 2 ◮ diffusion with D ( E ) ∝ τ esc ( E ) ∼ E − δ and δ ∼ 0 . 5 explains observed spectrum E − 2 . 6 electrons, positrons: τ loss ≪ τ esc and τ loss ∝ 1 /E electrons dN − /dE ∝ E − γ − 1 positrons dN + /dE ∝ E − γ − δ − 1 Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 3 / 18
Astrophysical sources for anti-matter: CR secondaries standard secenario for Galactic CRs: ◮ sources are SNRs: kinetic energy output of SNe: 10 M ⊙ ejected with v ∼ 5 × 10 8 cm/s every 30 yr ⇒ L SN , kin ∼ 3 × 10 42 erg/s ◮ explains local energy density of CR ǫ CR ∼ 1 eV/cm 3 for a escape time from disc τ esc ∼ 6 × 10 6 yr ◮ 1.order Fermi shock acceleration ⇒ dN/dE ∝ E − γ with γ = 2 . 0 − 2 . 2 ◮ diffusion with D ( E ) ∝ τ esc ( E ) ∼ E − δ and δ ∼ 0 . 5 explains observed spectrum E − 2 . 6 electrons, positrons: τ loss ≪ τ esc and τ loss ∝ 1 /E electrons dN − /dE ∝ E − γ − 1 positrons dN + /dE ∝ E − γ − δ − 1 ⇒ ratio n + ∝ E − δ n − ⇒ CR secondaries can not explain increasing positron fraction Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 3 / 18
Possible explanations for the PAMELA anomaly: Astrophysics: as primaries from ◮ pulsars ◮ supernova remnants (SNR) Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 4 / 18
Possible explanations for the PAMELA anomaly: Astrophysics: as primaries from ◮ pulsars ◮ supernova remnants (SNR) Dark matter ◮ requires large boost factors ∼ 100 ⋆ Sommerfeld enhancement ⋆ dense, cold clumps Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 4 / 18
Possible explanations for the PAMELA anomaly: Astrophysics: as primaries from ◮ pulsars ◮ supernova remnants (SNR) Dark matter ◮ requires large boost factors ∼ 100 ⋆ Sommerfeld enhancement ⋆ dense, cold clumps ◮ “exclusive” coupling to leptons Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 4 / 18
Supernova remnants Astrophysical explanations II: SNR [ P. Blasi ’09 ] N CR ( E ) ≫ N e ( E ) for energies E ≫ m p in acceleration region Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 5 / 18
Supernova remnants Astrophysical explanations II: SNR [ P. Blasi ’09 ] N CR ( E ) ≫ N e ( E ) for energies E ≫ m p in acceleration region significant e ± production by CRs even for small τ pp in source Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 5 / 18
Supernova remnants Astrophysical explanations II: SNR [ P. Blasi ’09 ] N CR ( E ) ≫ N e ( E ) for energies E ≫ m p in acceleration region significant e ± production by CRs even for small τ pp in source secondary e ± are accelerated, spectra becomes harder Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 5 / 18
Supernova remnants Astrophysical explanations II: SNR [ P. Blasi ’09 ] N CR ( E ) ≫ N e ( E ) for energies E ≫ m p in acceleration region significant e ± production by CRs even for small τ pp in source secondary e ± are accelerated, spectra becomes harder several important implications for CR physics: ⇒ increase of ¯ p/p , B/C, . . . Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 5 / 18
Supernova remnants Positron ratio from SNR: [ Blasi ’09 ] Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 6 / 18
Supernova remnants Antiproton ratio from SNR: [ Blasi, Serpico ’09 ] 0.001 Bohm-like ISM ISM+B term Total -/p 0.0001 p A term B term 1e-05 10 100 1000 Kinetic Energy, T [GeV] Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 7 / 18
Supernova remnants Antiproton ratio from SNR: Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 7 / 18
Supernova remnants Antiproton ratio from SNR: [ Blasi, Serpico ’09 ] J ¯ p,SNRs ( E ) ≃ 2 n 1 c [ A ( E ) + B ( E )] J p ( E ) where � E � E max � 1 � dω ω γ − 3 D 1 ( ω ) d E E 2 − γ σ p ¯ ξ + r 2 A ( E ) = γ × p ( E , ω ) , u 2 m ω 1 and � E max B ( E ) = τ SNR r d E E 2 − γ σ p ¯ p ( E , E ) . 2 E 2 − γ E Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 8 / 18
Supernova remnants Antiproton ratio from SNR: [ Blasi, Serpico ’09 ] J ¯ p,SNRs ( E ) ≃ 2 n 1 c [ A ( E ) + B ( E )] J p ( E ) where � E � E max � 1 � dω ω γ − 3 D 1 ( ω ) d E E 2 − γ σ p ¯ ξ + r 2 A ( E ) = γ × p ( E , ω ) , u 2 m ω 1 and � E max B ( E ) = τ SNR r d E E 2 − γ σ p ¯ p ( E , E ) . 2 E 2 − γ E A increases for large D and small u ⇒ old SNR Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 8 / 18
Supernova remnants Antiproton ratio from SNR: [ Blasi, Serpico ’09 ] J ¯ p,SNRs ( E ) ≃ 2 n 1 c [ A ( E ) + B ( E )] J p ( E ) where � E � E max � 1 � dω ω γ − 3 D 1 ( ω ) d E E 2 − γ σ p ¯ ξ + r 2 A ( E ) = γ × p ( E , ω ) , u 2 m ω 1 and � E max B ( E ) = τ SNR r d E E 2 − γ σ p ¯ p ( E , E ) . 2 E 2 − γ E A increases for large D and small u ⇒ old SNR constraints: t acc ∝ D ( E ) /u 2 < ∼ τ SNR and D ( E ) /u 2 ≪ u 1 τ SNR Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 8 / 18
Supernova remnants Advantage of a Monte Carlo framework: you don’t need to think Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 9 / 18
Supernova remnants Advantage of a Monte Carlo framework: you don’t need to think – easy to include: time-dependence of v sh , D, . . . Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 9 / 18
Supernova remnants Advantage of a Monte Carlo framework: you don’t need to think – easy to include: time-dependence of v sh , D, . . . interactions: production of multi-particle states Michael Kachelrieß (NTNU Trondheim) Antimatter from Supernova Remnants TeVPA, Paris 2010 9 / 18
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