Introduction to the High Energy Astrophysics Introductory lecture

Cosmic Ray Spectrum (nuclear component) Energy eV „Knee ” 1 particle/m 2 yr Particle Flux ( m2 s sr GeV ) -1 1 particle/m 2 s „Ankle ” 1 particle/km 2 yr 1 J  6  eV

Zakres wysokich energii E 2.5 Particle Flux Energy (eV)

SNR

Black Holes

Pulsary

Crab Nebula : : wide frequency range electromagnetic spectrum - 20 decades  fotons – over 9 decades ! COMPTEL EGRET HEGRA 100 keV – 100 TeV CELESTE E e ~10 15 eV IC: syn, opt, IR, micro, CMB B=160  G SYN

Quasars

Mkn 421 SYN IC czas w dniach eVTeV keV TeV High variability: one looks into vicinity of the central black hole Takahashi et al. 2000

Radiosources

Solar magnetosphere

20 Stars RadioInfraredVisible lightX-rays VHE gamma rays Dust Cosmic electron accelerators B Cosmic proton accelerators magnetic field adjusts relative height of peaks  ~  S pectral E nergy D istribution : Energy emitted per log(E) interval

Astronomical osbervation cover a wide range of electromagnetic waves with characteristic frequencies or photon energies: Astronomy uses observations of electromagnetic signals spanning over 20 decades in frequency 10 9 Hz – radio Hz – far IR Hz – close IR Hz – optical (eV) Hz – UV Hz – X-rays (keV) Hz – soft gamma rays (MeV) Hz – high energy gamma rays (GeV) Hz – very high energy gamma rays (TeV)

Observational windows of gamma ray astronomy : LE or MeV : MeV ( *) HE or GeV : GeV ( *) VHE or TeV : TeV ( *) UHE or PeV : PeV EHE or EeV : EeV are open in ranges of MeV, GeV, i TeV: LE,HE – observations from space VHE,.... -observations from the Earth surface * few scientific results

Basic emission processes with CR particles Elektrons: - Synchrotron emission („SYN”) - inmverse Compton emission („IC”) - nonthermal bremsstrahlung (usually not significant) Protons: - interactions p-p pions photons 

Synchrotron emission ("SYN") of relativistic electrons spiraling in the magnetic field Emission time scale Emmitted energy with maximum near (B -4  B/[10 -4 G]) Hz Dla B -4 =1 i E~ GeV -> 10 8 Hz TeV -> Hz PeV -> Hz lat for above B and E, respectively, ~10 6, ~10 3 i ~1 lat

Inverse Compton emission ("IC") of relativistic electrons scattering low energy photons Emission time scale (with U o,-10 = U o /[ erg/cm 3 ]) lat In the Thompson range ( o  < m e c 2, above: K-N) Energies of scattered photons For example, for scattering of CMB photons (  o ~10 -4 eV) and E e = 1 GeV, 1 TeV, 1 PeV one receives  ' = 100 eV, 100 MeV, 100 TeV

Cosmic objects of interest for High Energy Astrophysics quasars balzars Syfert 1 Syfert 2 AGN MAS jets kpc-scale jets radio lobes hot spots in radio lobes neutron stars black holes NSXB BHXB accreting X-ray pulsars rotation powered pulsars milisecond pulsars plerions SNR cataclysmic variables microquasars Sgr A* stellar winds near O/B GRB GRB afterglow soft gamma ray repeaters magnetars Solar protuberances interplanetary shock waves Earth magnetosphere CME cosmic rays high energy neutinos