GLAST Lunch Talk 5/12/05

PSR J2021+3651 and Pulsar Wind Tori Fitting

Stephen C.-Y. Ng(Romani Group)

GLAST Lunch Talk 5/12/05

Outline Gamma-ray Pulsars from 3EG catalogue Chandra Observation of PSR J2021+3651 Examples of PWN from Chandra Tori Fitting Results & applications Summary

GLAST Lunch Talk 5/12/05

Gamma-ray Pulsars

• Egret: Vela, Geminga, PSR B1706-44,…• More for GLAST• PSR J2021+3651 (Hessels et. al 04)

– 103.7ms period radio pulsar– Coincident with Egret Source GeV2020+3658– 19ks Chandra X-ray Observation

GLAST Lunch Talk 5/12/05

PSR J2021+3651

Spectral parameters

GLAST Lunch Talk 5/12/05

PWNe from Chandra

GLAST Lunch Talk 5/12/05

More examples

GLAST Lunch Talk 5/12/05

Model Torus3D torus model (Ng & Romani 03)

Parameters: ,,r, ,d

Poisson statistics, max likelihood

Error estimation-- Monte Carlo Simulation

GLAST Lunch Talk 5/12/05

Results

GLAST Lunch Talk 5/12/05

Results

GLAST Lunch Talk 5/12/05

Applications• Viewing Geometry for Gamma Ray emission

(Romani & Yadigaroglu 95)

• Spin axis - proper motion alignment=> Pulsar kick=> Core collapse physics

GLAST Lunch Talk 5/12/05

Pulsar KickCrab Vela

VV

GLAST Lunch Talk 5/12/05

Summary•PSR J2021+3651, which coincident with Egret source, shows PWN structure.

•Toroidal PWN is observed in many in energetic young pulsars.

•Torus model Fitting gives the viewing geometry:

-- to understand Gamma-ray emission mechanism.

-- to investigate spin-kick which gives new information on NS birth properties.