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Pulsars Multi-Accelerator Radiation model Peking University.

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Presentation on theme: "Pulsars Multi-Accelerator Radiation model Peking University."— Presentation transcript:

1 Pulsars Multi-Accelerator Radiation model Peking University

2 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

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

4 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.

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

6 Spectra Observation Cut-Off

7 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

8 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

9 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

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

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

12 Determine the Radiation Geometry

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

14 The Calculation for the Radiation Map

15 Relative intensity

16 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

17 ICS model sketch map

18 Calculation for Radio Radiation

19 Unified Results Gamma Radio1 Radio2

20 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

21 Vision

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

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

24 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

25 Geometry Condition

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

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

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

29 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

30 Further Work Dynamic & Kinetic

31 Thanks

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