Introduction to the High Energy Astrophysics
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Transcript of Introduction to the High Energy Astrophysics
Introduction to the High Energy Astrophysics
Introductory lecture
Cosmic Ray Spectrum
(nuclear component)
Energy eV
„Knee”1 particle/m2 yr
Par
ticl
e F
lux
( m
2 s
sr G
eV )
-1
1 particle/m2 s
„Ankle”1 particle/km2 yr
1 J 61018 eV
Zakres wysokichenergii
E
2 .5 P
arti
cle
Flu
x
Energy (eV)
SNR
Black Holes
Pulsary
Crab Nebula : : wide frequency range electromagnetic
spectrum - 20 decades fotons – over 9
decades !
COMPTEL EGRET
HEGRA100 keV – 100 TeV
CELESTE
Ee ~1015 eV
IC: syn,opt, IR, micro, CMB
B=160 G
SYN
Quasars
Mkn 421
SYN IC
czas w dniach
eV TeV
keVTeV
High variability: one looks into vicinity of the central black hole
Takahashi et al. 2000
Radiosources
Solar magnetosphere
20
Stars
Radio Infrared Visible light X-raysVHE
gamma rays
DustCosmic
electronaccelerators
B
Cosmic proton
accelerators
magnetic fieldadjusts relativeheight of peaks
~
SpectralEnergyDistribution:Energy emitted perlog(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
109 Hz – radio1011 Hz – far IR1014 Hz – close IR1015 Hz – optical (eV)1016 Hz – UV1018 Hz – X-rays (keV)1021 Hz – soft gamma rays (MeV)1024 Hz – high energy gamma rays (GeV)1027 Hz – very high energy gamma rays (TeV)
108
1029
Observational windows of gamma ray astronomy :
LE or MeV : 0.1 -100 MeV (0.1 -10 + 10 -100*)
HE or GeV : 0.1 -100 GeV (0.1 -10 + 10 -100*)
VHE or TeV : 0.1 -100 TeV (0.1 -10 + 10 -100*)
UHE or PeV : 0.1 -100 PeV EHE or EeV : 0.1 -100 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
222 )sin(2)( BUcP BTsyn
Emission time scale
24
19 )(105.2
Btsyn
Emmitted energy with maximum near (B-4 B/[10-4 G])
24100~3.0 Bc Hz
Dla B-4=1 i E~
GeV -> 108 HzTeV -> 1014 Hz PeV -> 1020 Hz
lat
for above B and E, respectively, ~106, ~103 i ~1 lat
Inverse Compton emission ("IC") of relativistic electrons scattering low energy photons
Emission time scale (with Uo,-10 = Uo/[10-10 erg/cm3])
110,0
110, )(10~
Ut TIC lat
oTTIC UcP 2, 3
4
In the Thompson range ( o < mec2 , above: K-N)
Energies of scattered photons2 o
For example, for scattering of CMB photons (o~10-4 eV)and Ee = 1 GeV, 1 TeV, 1 PeV one receives ' = 100 eV, 100 MeV, 100 TeV
Cosmic objects of interest for High Energy Astrophysics
quasarsbalzarsSyfert 1Syfert 2AGNMAS jetskpc-scale jetsradio lobeshot spots in radio lobes
neutron starsblack holesNSXBBHXBaccreting X-ray pulsarsrotation powered pulsarsmilisecond pulsarsplerionsSNRcataclysmic variablesmicroquasarsSgr A*stellar winds near O/B
GRBGRB afterglowsoft gamma ray repeatersmagnetars
Solar protuberancesinterplanetary shock wavesEarth magnetosphereCME cosmic rays
high energy neutinos