Presentation is loading. Please wait.

Presentation is loading. Please wait.

Neutrinos and TeV photons from Soft Gamma Repeater giant flares Neutrino telescopes can be used as TeV  detectors for short time scale events using 

Similar presentations


Presentation on theme: "Neutrinos and TeV photons from Soft Gamma Repeater giant flares Neutrino telescopes can be used as TeV  detectors for short time scale events using "— Presentation transcript:

1 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

2 What are SGR’s? X-ray stars emitting short (~100 ms) bursts in X/soft  -ray typically of energy 10 41 D 10 2 ergs Steady X-ray emission with luminosities 10 35 -10 36 D 10 2 erg/s with OTTB+power law spectra E -(1  3) From slow down rate of steady emission period (5-8 s)  huge magnetic fields B ~10 14 -10 15 G Similar to 8 Anomalous X-ray Pulsars but typically these do not emit bursts (1 exception) 5 galactic except for SGR 0526-66 in LMC http://solomon.as.utexas.edu/magnetar.html Woods & Thompson, astro-ph/0406133

3 The Magnetar Model and emission Steady X-ray emission powered by decay of n star magnetic field Luminosities 10 35 -10 36 D 10 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

4 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 10 6-7 less intense but d 2  10 10 Detected radio afterglows imply relativistic outflows + huge luminosities with barion loading  fireball (Piran et al, astro-ph0502148, Ioka et al, astro-ph/0503279)

5 Giant flare energy SourceSGR1900+14 (1998)SGR1806-20 (2004) Duration0.35s0.25 s Fluence in initial pulse (ergs/cm 2 ) >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 1 st 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 ~10 47 erg in 600 ms

6 The SGR 1900-14 Aug 27, 1998 giant outburst Beppo-Sax (Feroci et al, 1999) A) 0-67 sec 70-650 keV OTTB+PL E -1 exp(-E/31.2 keV)+E -1.47 B) 68-195 sec 70-400 keV OTTB E -1 exp(-E/34.2 keV) + E -4.5 C) 196-323 sec 70-400 keV OTTB E -1 exp(-E/28.9 keV) E -1.47 Guidorzi et al, 2004: response function of GRBM was not well known at large off-axis angles  70-600 keV only and 10% sys error

7 Spectrum Extrapolation at TeV energies OTTB+PL fits New best fit accounts better for the <60 keV region but for HE we use negative power law and vary it to account for the errors Guidorzi private communication

8 Muons from Gammas Competition of pion interaction and decay in the atmosphere (Drees Halzen Hikasa, PRD39, 1989, Stanev Gaisser Halzen PRD32 1985) : AMANDA-II horizontal averaged area = 30000 m 2 and 0.3 s At South Pole:  =-20˚   = 70˚  spectra Pion photoproduction cross section in FLUKA  energy to produce  of energy E E ,th = 10 GeV

9 Muon signal But this particular flare was at 68˚ and Milagro analyses are commonly performed up to 45˚ astro-ph/0110513 1 Hz in 8 2 deg 2 and 0.3 s at 5 km depth 0.8 6 Gamma showers in MILAGRO

10 For a source below horizon as SGR1900+14 But also horizontal muons from neutrinos but 1/ 2.65 Upward-going muons and cascades in AMANDA

11 Conclusions We calculated possible muon and neutrino rates for Dec 27 giant flare as a function of spectrum. AMANDA can constrain it ! Relevant time scale of the order of 0.1 s and spatial constraint allow a search using downgoing muons We should use the neutrino cascade channel and look for neutrino induced muons We will preferably use IceTray or SIEGLINDE Start from raw data -> ROOT files


Download ppt "Neutrinos and TeV photons from Soft Gamma Repeater giant flares Neutrino telescopes can be used as TeV  detectors for short time scale events using "

Similar presentations


Ads by Google