Neutrinos produced by heavy nuclei injected by the pulsars in massive binaries Marek Bartosik & W. Bednarek, A. Sierpowska Erice ISCRA 2004

6 July 2004 ISCRA Erice The purpose  Neutrinos from massive binaries e.g. Gaisser & Stanev 1985 Berezinsky et al large angles – non eclipsing binaries

6 July 2004 ISCRA Erice Binary system What we need? Binary with an energetic pulsar no accretion small separation star with massive & fast wind  WR or OB – perfect

6 July 2004 ISCRA Erice The shock geometry  The geometry of the shock is described by the parameter  = L em /(c M loss V WR ), which is the ratio of momentum carried by the pulsar wind and the momentum of the stellar wind. L em = 6  B 12 2 P -4 erg s -1,  The distance from the pulsar to the termination shock is:  =  1/2 D(1+  1/2 ) Ball & Dodd 2001

6 July 2004 ISCRA Erice Scenario

6 July 2004 ISCRA Erice Parameters  =0.06 Cygnus X-3 d=10kpc

6 July 2004 ISCRA Erice Iron from the NS surface  Binding energy of the iron nuclei on the NS surface is not known (  2-3keV?).  It is assumed that iron nuclei can be emitted for (Usov&Melrose, 1995)  Temp. of NS star surface can be high enough:  In a short time after its formation  As a result of heating of the polar cap by e-m cascades (polar cap model)

6 July 2004 ISCRA Erice Acceleration of nuclei  Charged particles can be accelerated to the energy  Expected Lorentz factors of iron nuclei in Cyg X-3 Arons, 1998 Arons  0.3 (for Crab) then -  10 7

6 July 2004 ISCRA Erice Optical depth Optical depths for dissociation of single nucleon in the PWZ for different angles of injection (from 0  to 150  )

6 July 2004 ISCRA Erice Nucleons extraction Number of dissolved nucleons from primary iron nuclei during their propagation in the PWZ for angles from 0  to 150 

6 July 2004 ISCRA Erice Shock zone  The magnetic field at the termination shock at the „pulsar side” is  10 3 G  Larmor radius for iron nuclei with Lorentz factor  10 6 is  cm  Iron nuclei & protons can pass through the shock.

6 July 2004 ISCRA Erice Magnetic field of WR star r A - Alfven radius Eichler & Usov, 1993

6 July 2004 ISCRA Erice Nucleons above the PWZ  Part of nucleons extracted from iron nuclei and remnant nuclei impinge onto the massive star.  Hadrons lose energy on pion production during their propagation in the WR star atmosphere Atmosphere model: Hamann 1985

6 July 2004 ISCRA Erice Can we get a neutrino? If pion decays and neutrino & muon are produced.

6 July 2004 ISCRA Erice Spectra of neutrinos - comparison 0.2 R star - red 0.4 R star -green 0.6 R star - blue 0.8 R star - violet Lorentz factors thick thin Modulation due to companion star matter

6 July 2004 ISCRA Erice Integral neutrino fluxes Integral neutrino fluxes as a function of the impact parameter for the observer in the plane of the binary system at energies above: 10 2 GeV - black 3  10 2 GeV - red 10 3 GeV - green 3  10 3 GeV – blue (  =10 6 – thick,  =10 7 – thin)

6 July 2004 ISCRA Erice Spectra of neutrinos Spectra of neutrinos for different viewing angles in respect to the plane of the binary; cos  : (black line), (red), (green) and (blue).  is azimuthal angle.  =

6 July 2004 ISCRA Erice Conclusions  Heavy nuclei, if injected by a compact object inside the close massive binary (e.g. similar to Cyg X-3), can significantly disintegrate in the radiation field of a massive star.  Some neutrons dissolved from the nuclei impinge on the massive star surface producing high energy neutrinos in the plane of the massive binary.  Some protons and neutrons dissolved from nuclei and remnant nuclei, after propagation in the magnetic field of the massive star above the pulsar termination shock, can also impinge on the massive star surface producing neutrinos at large angles to the plane of the binary system.  The flux of neutrinos produced at large angles to the system plane is about 30% of the flux produced in the cone intercepted by the massive star in the considered case.

6 July 2004 ISCRA Erice