Neutrinos and TeV photons from Soft Gamma Repeater giant flares Neutrino telescopes can be used as TeV detectors for short time scale events using s from photoproduction in showers ! Can AMANDA detect a signal from 27 Dec. giant flare from SGR 1806-20 (above horizon)? In what channels? • Review soft-and X-ray observations on SGR giant flares • A toy model based on Beppo-SAX SGR 1900-14 spectrum • Muon and Neutrino signals • Backgrounds • Useful information for the blind data analysis Francis Halzen, Hagar Landsman, Teresa Montaruli astro-ph/0503348 LBL, IceCube Meeting, Mar. 2005
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Neutrinos and TeV photons from Soft Gamma Repeater giant flares Neutrino telescopes can be used as TeV detectors for short time scale events using
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Neutrinos and TeV photons from Soft Gamma Repeater giant
flares
Neutrino telescopes can be used as TeV detectors for short time scale events using s from
photoproduction in showers !Can AMANDA detect a signal from 27 Dec. giant flare
from SGR 1806-20 (above horizon)? In what channels?
• Review soft- and X-ray observations on SGR giant flares • A toy model based on Beppo-SAX SGR 1900-14 spectrum• Muon and Neutrino signals• Backgrounds• Useful information for the blind data analysis
Francis Halzen, Hagar Landsman, Teresa Montaruliastro-ph/0503348
LBL, IceCube Meeting, Mar. 2005
What are SGR’s?
• X-ray stars emitting short (~100 ms) bursts in X/soft -ray typically of energy 1041 D10
2 ergs
• Steady X-ray emission with luminosities 1035-1036 D10
2 erg/s with OTTB+power law spectra E-(13)
• From slow down rate of steady emission period (5-8 s) huge magnetic fields B ~1014-1015 G
• Similar to 8 Anomalous X-ray Pulsars but typically these do not emit bursts (1 exception)
The Magnetar Model and emissionSteady X-ray emission powered by decay of n star magnetic field Luminosities 1035-1036 D10
2 erg/s periodic (5-8 s)
Neutrinos: Zhang et al ApJ 595 (2003)the potential drop through the magnetosphere of the rotating n star might accelerate protons above photomeson threshold (depends on n star period and B and geometrical factor) interaction on thermal radiation from heated n star surface
Rates strongly depend on beaming angle around polar axis
dN/dE E-2
Why giant flares?
•3 ‘giant’ flares: VERY HARD component dN/dE E-1.5-1.7 (Cheng et al., Nature 1996)
•Dec. 27, 2004 peak lasting 0.25 s followed by a 300 s long tail with 7.57 s
period and -140 s precursor (INTEGRAL, GCN2920) following previous series of bursts: Dec 21 and Oct 5. Still active.
Rearrangements of magnetic field and formation and dissipation of strong localized currents. These may fracture the rigid crust that outbursts
Can be a process in which nucleons and nuclei are accelerated
Similar to small GRB’s: SGR giant flares are 106-7 less intense but d2 1010
Detected radio afterglows imply relativistic outflows + huge luminosities with barion loading fireball (Piran et al, astro-ph0502148, Ioka et al, astro-ph/0503279)
Giant flare energy
Source SGR1900+14 (1998)
SGR1806-20 (2004)
Duration 0.35s 0.25 s
Fluence in initial pulse (ergs/cm2
)
>5.5·10-3 (Konus-Wind 15-250 keV)>6.4 10-4
(Beppo-SAX 40-700 keV)
2.4!!(GEOTAIL)>0.1 (RHESSI)Ge detectors up to 15 MeV saturated
No spectral measurement of the 1st s available. X-ray detectors suffered saturation effects. SGR 1900+14 AMANDA B-10
Beppo-SAX: Spectrum for first 68s up to 700keV (1s resolution)
SGR 1806-20 AMANDA-II (critical period) No spectrum available.
Similar flare. >2 orders of magnitude stronger
GEOTAIL (astro-ph/0502315) not saturated: measured fluence implies for d = 15 kpc a very efficient mechanism that releases ~1047 erg in 600 ms
The SGR 1900-14 Aug 27, 1998 giant outburstBeppo-Sax (Feroci et al, 1999)
A) 0-67 sec 70-650 keV OTTB+PL E-1 exp(-E/31.2 keV)+E-1.47