SENSIBILITA DEL TELESCOPIO ANTARES PER NEUTRINI IN COINCIDENZA CON GAMMARAY BURST

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Neutrino oscillations and astrophysical fluxes
c cos?sol, s sin?sol, ?sol35o x sin?atm
cos?atm, ?atm 450 ?matm2.5 ?10-3 eV2,
?msol7?10-5 eV2
For astrophysical sources Lgtkpc ?m2
L/2E 1
Beam dump when all ms decay
Other scenarios neutron decay
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Neutrino production top down
Decay of neutrons in sources Decay or
annihilation of supermassive relic of Big Bang
1024 eV 1015 GeV MGUT (monopoles, topological
defects, vibrating strings)Resonant UHE
neutrino interactions on relic neutrinos
(Z-bursts)Guaranteed neutrinos GZK
nsUHECR produce ps ?ns ns from CR
interactions in the
Galactic plane
Can explain EHECR
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The Galactic Plane
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The Galaxy
Halo
Sun
Ring bar
Galactic center
Bulge
spiral arms
Sun
1 pc 3.3 ly
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g observations

• EGRET observed a diffuse emission 100MeV-10 GeV
  from Galactic Centre region (300 pc) excess gt
  factor 10 around 1 GeV
• INTEGRAL resolved 91 point sources. 90 of
  diffuse flux can be due to point sources lt100
  keV
• Milagro discovery of TeV emission
  (astr-ph/0502303)
• 4.5s excess from blt5 and l?40,100
• Covered pond with 2 layers of PMTs, from
  relative timing 0.75 shower direction
  resolution, gamma-hadron discrimination based on
  shape of Cherenkov light emitted by showers

FMilagro(gt1TeV)5.1 10-10 cm-2 s-1 sr-1 Steeper
than EGRET alone 2.51 ?0.05
2.610.07
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g observations

• Extreme models g -(2.4-2.9) (hard electron
  disfavoured)
• ns follow primary spectrum (p decay dominates
  over interactions)
• New model in Strong, Moskalenko, and Reimer,
  astro-ph/0406254

INTEGRAL flux from point sources
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Extreme Models
Hard nucleus model E-2.4
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Galactic Centre

• High matter density and activity
• compact radio source Sgr A possibly associated
  to black hole 3 106 Msun in the center
• Sgr A East SNR

HESS TeV-g spectrum in disagreement with the
other experiments Variability? localization? HESS
1 arcmin around Sgr A
HESS (6.1s 4.7h/9.2 s 11.8 h)
astro-ph/0408145
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High Energy Stereoscopic System
Four 12 m diameter telescopes running since 1yr
in Namibia (16 in the future?) Eth ? 100
GeV Cherenkov light is emitted by showers
induced by high-energy gamma rays This light is
very faint - about 10 gs/m2 at Eg100 GeV - and
the duration of the light flash is only a few
nsec. Large mirrors, fast photon detectors and
short signal-integration times are required to
collect enough light from the shower, with
minimal contamination from night-sky background
light. g direction lt 0.1?
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Galactic point Sources
The case of RXJ1713.7-3946
Open problem elusive p0 produced in accelerated
nuclei collisions with SN ambient material. Still
not a clear evidence BUTCANGAROO claim
Enomoto et al, Nature 2002
Controversial Reimer et al., AA390,2002 Incompati
ble with EGRET
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RXJ1713.7-3946
No cut-off in the HE tail of HESS spectrum favors
p0 decay scenario respect to the case of em
processes Study of electron density and B can help
NB CANGAROO measures the spectrum for the NW part
of the rim, HESS for the entire region
RXJ1713.7-3946 Seen by HESS
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Microquasars
Galactic X-ray binaries with radio relativistic
jets Their structure make them similar to
quasars but 106 times smaller Most have
bursting activity (hrs-days) Persistent SS433
GX339-4
Neutrinos from p-g interactions (photons from
synchr. emission of electrons accelerated in jet
or from accretion disc)

• Ljet jet kinetic power (erg/s)
• d jet Doppler factor d ?(1- ß cos?)
• ?p fraction of jet energy transferred to
  protons (0.1)
• fp fraction of p energy transferred pions
• D source distance

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Predictions Galactic sources
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Gamma-Ray Bursts
Vela-4 detects the 1st g emission E?gt0.1 MeV on
July 2nd,1967
BATSE (?1 GRB/d, 3 error box, FoV 4? sr)
EGRET (1 GRB/yr, 10 arcmin, Egt30 MeV,FoV 0.6 sr)
1 arcmin 1/60 deg
Counting rates with time variable from GRB to GRB
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BATSE observations on GRBs
Band et al.
Parametri ?, ? e E0
E0?200 keV
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Beppo-SAX and afterglows
Beppo-SAX (54 GRBs/6yrs, 5 error box, 40-700
keV, FoV 20 ? 20 )
Determined in 5-8 h precise GRB position thanks
to detection in X (WFC)
Xray afterglow discovery delayed emission even
after 1d ? optical counterparts SN
association GRB980425-SN1998bw
GRB030329-SN2003dh position coincidence and
SN like spectrum in afterglow Long GRBs stellar
core collapse into a BH, accretes mass driving a
relativistic jet that penetrates the mantle and
produces GRB Controversial observation off-axis
suppresses g flux
From optical afterglow spectrum redshift ?
cosmological distance
Emitted energy (isotropic) ?1054 erg
Beaming (light curve changes in slope) q 1/G
Eobs G Eemitted G102-103 Eemitted 5 1050
erg
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Current and future missions
Delay of satellite data processing
and transmissiontransmission of alerts
The Gamma-ray bursts Coordinate network GCN
Distribution of alerts
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The fireball model
Compactness problem the optical depth for pair
production very high if initial energy emitted
from a volume with radius R ltc dt 300 km with dt
variability time scale ms in photons with the
observed spectrum ? this would imply thermal
spectra contrary t observations Solution
relativistic motion dimension of source R ltG2 c
dt and Eobs G Emitted
A fireball (?, e?, baryon loading lt10-5 Msun to
reach observed G) forms due to the high energy
density, that expands. When it becomes optically
thin it emits the observed radiation through the
dissipation of particle kinetic energy into
relativistic shocks External shocks relativistic
matter runs on external medium, interstellar or
wind earlier emitted by the progenitor Internal
shocks inner engine emits

many shells with different Lorentz

factors colliding into
one another, and

thermalizing a fraction of their kinetic

energy
Review
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Active Galactic Nuclei
Rotating massive BH with jets along rotation axis
with matter outflow accretion disc Spectra
have a thermal part due to synchrotron radiation
of electrons in a magnetic field (UV bump at
optical-UV frequencies)non thermal
component extending up to 20 orders of
magnitude explained by leptonic/hadronic
models Neutrino production in pg or pp processes
VLA image of Cygnus A
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Upper bounds on X-galactic fluxes
Cosmic p accelerators produce CRs, gs and ns
Ultimate bound of
any scenario involving n and g production from
ps diffuse extra-galactic g background E2Fn lt 6
10-7 GeV /cm2 s sr (EGRET) Measured UHECR flux
provides most restrictive limit (Waxman Bahcall
(1999) -
optically thin sources nucleons from
photohadronic interactions escape
- CR flux above the ankle (gt3 1018eV)
are extragalactic protons with E-2 spectrum ?
E2Fn lt 4.5 10-8 GeV /(cm2 s sr)

• This bound does not apply to harder
• spectra or optically thick

Mannheim, Protheroe Rachen (2000) Magnetic
fields and uncertainties in photohadronic
interactions of protons can largely affect the
bound as these effects restrict number of
protons able to escape
CR rate evolves with z
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Suggested references

• Halzen and Hooper, Rept.Prog.Phys.651025-1078,200
  2
• Learned and Mannheim,
• Ann.Rev.Nucl.Part.Sci.50679-749,2000
• Burgio, Bednarek, TM, New Astron. Rev. 49, 2005
  (galactic point sources)
• http//arxiv.org/PS_cache/astro-ph/pdf/0405/040550
  3.pdf (GRBs)
• Books Longair, High Energy Astrophysics
  Berezinski, Neutrino Astrophysics 1995
• These transparencies
• http//www.icecube.wisc.edu/tmontaruli/

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Neutrino Detection Principle

• ns are weekly interacting ?
• require large target mass and
• conversion into charged particle
• Markov/ Greisen idea (1960)
• Target is surrounding matter
• M r Rm S (Em 1 TeV Rm 2.5 km)
• Events are upgoing

Muon neutrinos are the only topology to allow
source pointing But since ns oscillate other
topologies should be considered that allow to
observe upper sky
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Energy losses
Ionization and atomic excitation interactions
with electrons in the media Continuous
process mip particles at the minimum of
ionization 2 MeV/g/cm2 Radiative discrete
process and stochastic Bremmsstrahlung radiation
emitted by an accelerated or decelerated particle
through the field of an atomic nuclei Energy
emitted ?1/m2 Pair production mN ?
ee- Photonuclear inelastic interaction
of muons with nuclei, produces hadronic showers
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The target mass
Ionization Stochastic losses 2 MeV/g/cm2
(dominate gt 1TeV )
critical energy
Upgoing muons much larger interaction volume
than what is in the instrumented region