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Probe into Magnetic Field and Initial Period of Neutron Star Basis Two models 72 Pulsars data with transverse velocities( form Dr Wang, possible recycle pulsars are deducted) Superfluid Vortex of NS Vortex flow Vortex core (normal neutrons) Spin-down by neutrino radiation from superfluid vortex (Basic theory: Peng et al.1982) It is general believed that neutron superfluid in the interior of neutron stars is in a vortex state, and the vortex lines are parallel to the rotation axis of the neutron star. The circularly moved neutrons may emit neutrino pairs owning to the weak interaction of the neutral current. Radiation power: the superfluid neutrons plus normal neutrons Wv BG(n) G(n) n7 / n B 1.0 1057 (8 / 2/ 3 )Rs3 n is the vortex quantum number; is the energy gap caused by the interaction of attraction of the 1S0 wave between neutrons. Rotation energy of the neutron star keeps infusing to the supfluid vortices via “Ekman pump mechanism”. Hybrid model Rotation energy loss rate: Period derivative: Assumptions: Magnetic field: Age: Braking index: (Dipole model+Superfluid) (n decreases with increased P) Contrast between the two models items Hybrid Model Period derivative Magnetic field Age Braking index 3 n 3 Dipole Model The observed kick velocities for Pulsars V(km/s) Number Percentage 100 71 75% 300 36 38% 500 14 15% 1000 5 5% Parity violation Ji J Jf p n J i J J f n Neutrino Jet Rocket Model If the neutron angular momentum is carried away mainly by neutrinos, the direction of emitted neutrinos with left hand spin must be opposite to the original neutron angular momentum , while the neutron itself will get a recoil along its angular momentum direction. On the contrary, If the neutron angular momentum is carried away mainly by the anti-neutrinos, the direction of the emitted anti-neutrinos with right hand spin must be the same as the original neutron angular momentum direction , while the neutron itself will get a recoil opposite to its angular momentum direction. Formulae W dV M dt c :Asymmetry factor 2 CG ( n ) B dP 0 12 V P0 McA0 ( P ) (1 B G (n ) B 2 ) P 3 P 3 0 0 12 0 P0 P 72 Pulsars’ B12 and P0 According to upwards models, we calculate 72 Pulsars’ B12 and P0 ,here we choose =3.0 to simplify solving the non-linear equations, and closed 3 makes for acceleration. For each pulsar, we choose least n0 make equation solved. Calculation Results P0 min=0.000423s ( B12 =2.832, n0=950 V=2500km/s) B12 max=27.558 (P0 =0.00057s, n0=1115,V=252km/s ) 2) Hybrid Model can reduce magnetic field calculated by Dipole Model effectively. n0 max=1325 (B12=11.725,P0=0.000433s, V=1730km/s) P0 P0_n0 0.006 0.005 0.004 0.003 0.002 0.001 200 B12 400 600 800 B12_n0 20 15 15 10 10 5 5 400 600 1200 P0 20 200 1000 800 1000 1200 n0 B12_P0 n0 0.001 0.002 0.003 0.004 0.005 0.006 B12 Statistics and Fit n0 Log B12 P0 Correlation coefficient:0.882565 _Log n0 7 6.5 6 5.5 6 8 10 Log B12 P0 B12 ln n0 0.264 ln( ) 4.312 P0 Physics Signification The B12 is higher, that is said, the presupernova collapsed more fiercely, so the interior overfall is more disordered, it can be anticipated n0 is larger. If P0 increased,because of angular momentum conversation law,we can draw same conclusion. Conclusion and Discussion 1) Neutrino Jet Rocket Model is a gradual acceleration model, main accelerating period : P 0.5 s, Vmax 1000 km/s 3)Use the connection of B12-n0-P0, maybe solve the problem of high magnetic field and calculate more pulsars’ velocities etc. 4)More work should be done about making certain involved parameter more reasonably. Thank you!