Presentation on theme: "Pulsars Multi-Accelerator Radiation model Peking University."— Presentation transcript:
Pulsars Multi-Accelerator Radiation model Peking University
Outline n The difficulties of present pulsar models n The apocalypse from observation & theoretical research n A new acceleration region and a new model n Properties of this model n Comparing to observations
Pulsars + - - + Null surface 1.Strong magnetic field 2.Rapidly rotation Pulsar
Difficulties of present model There are two kinds of models For Polar Gap Model (Muslimov & Harding 2003) Require small inclination angle and impact angle For Outer Gap Model (Cheng et al 1986, 1994, 2000...) No off-pulse emission No Tev cut-off Too sharp rise of pulse profile We will solve these problem here.
Observation Note The radio pulse is narrow. The gamma-ray pulse is wide. Bridge emission Off pulse emission
The apocalypse from observation Pulse profile show: n The radio radiation comes from a compact region while gamma-ray radiation comes from a wide region Spectra show n Tev cut-off require the radiation location not far from the pulsar
The theory of pulsar radiation Polar Gap Model n Radiation locates at the magnetic pole of the pulsar Outer Gap Model n Radiation locates outside the null surface,far from the pulsar
Reasons for Difficulties of Present Model For Polar Gap Model Require small inclination angle and impact angle Reason n Too near For Outer Gap Model No off-pulse emission No Tev cut-off Too sharp rise of pulse profile Reason Too far
New Radiation Location n We note the so called Mid-Gap n It locates near than Outer Gap n Farther than Polar Gap
Input Physics 1. The radiation direction 2. The intensity of radiation 3. NOTE: only at this time! We will calculate the physics very soon.
Radio? n We also consider the radio radiation in this region n Take the Inverse Compton Scatter model to calculate the radio radiation Have the intrinsic Beauty of Unification! n Not a machine made model
The Equation and Numeric Method n The Radiation Transfer Equation is rather hard to integrate. n Delta like and infinite integration
The Escape Membrane of the Photons Solve: To get the location of source
Spectra Result Tev cut-off Solve the spectra problem of outer gap Fit the crab
Our Work Study a new gamma-ray pulsar model with a new accelerator Investigate the possible acceleration mechanisms Discuss the physical and geometrical conditions of this region Discuss the spectra properties induced by gamma-B process Give the last escape membrane of photons. Compare our model with observation