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Pulsars Multi-Accelerator Radiation model Peking University

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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

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Pulsars + - - + Null surface 1.Strong magnetic field 2.Rapidly rotation Pulsar

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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.

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Observation Note The radio pulse is narrow. The gamma-ray pulse is wide. Bridge emission Off pulse emission

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Spectra Observation Cut-Off

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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

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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

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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

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New Radiation Location n We note the so called Mid-Gap n It locates near than Outer Gap n Farther than Polar Gap

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Input Physics 1. The radiation direction 2. The intensity of radiation 3. NOTE: only at this time! We will calculate the physics very soon.

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Determine the Radiation Geometry

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Abbreviation Correction n The abbreviation will affect the direction of radiation. V c c oo

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The Calculation for the Radiation Map

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Relative intensity

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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

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ICS model sketch map

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Calculation for Radio Radiation

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Unified Results Gamma Radio1 Radio2

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The result of our model 1.Beam patterns 2.Pulse profile We have Bridge Emission Off-pulse Emission Soft rise and down Sight Line Vela

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Vision

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Multi-bands Fitting of Observations Vela Crab Geminga ICS model is used to give radio results Gamma-ray Radio

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Predictions 1.Some pulsar could be only observed at certain bands 2.Some pulsar can be observed at many bands 3.Three components pulsar

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Gamma-B Process n Gamma-B process 1.If the photons fly with some angle respect to the magnetic field 2.The photons have enough energy 3.Strong enough magnetic field The absorption ratio is Cm^-1

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Geometry Condition

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The Equation and Numeric Method n The Radiation Transfer Equation is rather hard to integrate. n Delta like and infinite integration

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The Escape Membrane of the Photons Solve: To get the location of source

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Spectra Result Tev cut-off Solve the spectra problem of outer gap Fit the crab

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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

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Further Work Dynamic & Kinetic

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Thanks

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