1、Qiao,G.J. Dept. of Astronomy, Peking Univ. Collaborators: Zhang, B.(University of Nevada), Xu, R.X.(PKU), Han,J.L.(NAOC), Lin,W.P.(SHO),Lee,K.J.(PKU) Xia,X.Y.,Radio and Gamma-ray emission of pulsars,Radio and Gamma-ray emission of pulsars,I. Radio emission (Inverse Compton scattering model: ICS ) II
2、. Inner annular gap & gamma-ray emission Radio + Gamma ray emission III. Pulsar: Neuron stars or Strange stars?,Core beam Beam-frequency Mode changing,Bi-drifting,Gamma-ray,Core gap,Annular gap,Strange stars,Pulsar emission beams,Observations,Emission beams,Rankin, 1983, ApJ,274,333,Theories,Ruderma
3、n & Sutherland (RS) Model,Ruderman & Shutherland,1975, ApJ,196,51,Emission beams in RS model,Ruderman & Sutherland, 1975,Emission beams,Hollow cone only!,Obs. & Theory(ICS),(1) Core + Cones(2) Different components comefrom different locations(3) Pulse profile shapes changing with freq.(4) Mode chang
4、ing(5) Bi-driftingPulsars: NS or Strange stars?,ICS Model: emission beams Core +cones,Qiao, 1992,ICS: shift of emission beams,Different emission locationshift of the emission beams,Qiao & Lin, 1998, A&A,333,172,Poln: Beam shiftPA jumps,Xu, Qiao & Han, 1997, AA,Poln: PA jump,Xu, Qiao & Han, 1997, AA,
5、ICS model: inner gap sparking 0,=220(1-Cosi),Qiao & Lin, 1998, A&A,Core beam Beam-frequency Mode changing,Bi-drifting,Gamma-ray,Core gap,Annular gap,Strange stars,RS model,Qiao,Liu, Zhang,& Han, 2001,AA,Lyne & Manchester (1988) & Sieber et al. (1975),Kramer,(1994),“S” shape PA & Obs.,Poln of integra
6、ted pulse in ICS,Vcircular poln,LLinear poln,ITotal Intensity,Position angle,Xu,Liu,Han,Qiao, 2000, ApJ,Core beam Beam-frequency Mode changing,Bi-drifting,Gamma-ray,Core gap,Annular gap,Strange stars,Mode changing of pulsars,Rankin, 1986,Zhang,Qiao,Lin,Han, 1997,Tree mode of sparking,Thermal ICS,Cur
7、vature radiation,Resonant ICS,Mode change pulsars,Zhang,Qiao,Lin,Han, 1997,ApJ Zhang,Qiao, Han, 1997,ApJ,Core beam Beam-frequency Mode changing,Bi-drifting,Gamma-ray,Core gap,Annular gap,Strange stars, Polar cap (polar gap),Basic Observational facts vs Theories,Radio- Gamma-rays:Obs.,Outer gap,Gamma
8、-ray,Radio,The magnetosphere of a NS,+,Inner annular gap,Inner annular gap,Qiao,Lee,Wang,Xu, Han, 2004a,ApJL,Inner annular gap,Qiao,Lee,Wang,Xu, 2004a, ApJL,Inner Annular Gap,Qiao,Lee,Wang,Xu, 2004a, ApJL,Core beam Beam-frequency Mode changing,Bi-drifting,Gamma-ray,Core gap,Annular gap,Strange stars
9、,Mclaughlin 2003,astr-ph/0310454,Bi-drifting: Obs.,Drifting subpulses,PULSE LONGITUDE,Drifting subpulses,Taylor et al. (1975),Backer (1973),Accelerators: Inner vacuum gap (Ruderman & Sutherland 1975) requiring high binding energy of charges on stellar surface,Drifting sub-pulses,Xu,Qiao Zhang, 1999,
10、ApJL,522,L112Deshpannde & Rankin, 1999,ApJ, 524,1008,Inner Annular Gap : V= c E x B / B2,Bi-drifting: fitting,Mclaughlin 2003,astr-ph/0310454,Qiao,Lee,Zhang,Xu,Wang,2004b, ApJL,Neutron stars:Binding energy 10 KeVno gap can be formed!Binding energy 10 KeVonly one gap cab be formed:core or annular gap
11、Strange stars:both core & annular gap can be Formed !, Annular Gap mole: different Gamma-ray pulsars can be fitted Pulsars: Strange stars? Observational check: Polarization at high energy bands Theory: two caps=two gap?,Conclusion and discussion,Core beam Beam-frequency Mode changing,Bi-drifting,Gam
12、ma-ray,Core flow,Annular flow,Neutron stars,?,?,?,Qiao,Lee,Zhang, Wang & Xu,2005,Can free flow produce drifting pulses? If not, can we distinguish NS from SS? More drifting phenomena need to be obs. Sub-millisecond pulsar need to be found?100 m telescope will be helpful for the research above!,?,100
13、m at Effelsberg,New Green Bank Telescope,Jodrell Bank,KaShi,China ?,Thank you !,Multi-cones in the ICS model,Qiao,Wang,Wang,Xu, 2002,ChJAA,Multi-frequency fitting of PSR J0437-4715,Qiao,Wang,Wang,Xu, 2002,ChJAA,Magnetosphere of pulsars,Goldreich & Julian (1969),Charge density GJ(Goldreich & Julian 1
14、969 ),Acceleration electric field,Inner annular gap,Qiao,Lee,Wang,Xu, Han, 2004,Ruderman & Sutherland, 1975,Neutron stars: binding energy 10KeV,Cant form core and annular gap at the same time!,Strange stars: binding energy 10KeV,Can form core and annular gap at the same time!,Interstellar Dispersion
15、,Ionised gas in the interstellar medium causes lower radio frequencies to arrive at the Earth with a small delay compared to higher frequencies. Given a model for the distribution of ionised gas in the Galaxy, the amount of delay can be used to estimate the distance to the pulsar. P-period DM-disper
16、sion measure,Crab pulsar,Vela Pulsar,Geminga,Inner annular gap,Qiao,Lee,Wang,Xu, 2003,PA jumps: individual pulses ?,Stinebring et at. 1984,OPM Depolarization (Xu.R.X), Orthogonal Poln Mode (OPM) Depolarization (Low LP ?Or Low LPOPM ?,Daugherty & Lerche, 1975,The “Death line” of radio pulsars,The Dea
17、th line of radio pulsars,Death and appearance line,Qiao et al.,2003,Sparking condition !,Does not Hubble line!,The Death line of radio pulsars,Qiao & Zhang,1996,The magnetosphere of a NS,Critical field line,NCS,Low L PolnOPM ?,Xu & Qiao, 2000, Science in China,Outer Gap Model,Emission beams: 1 &4：to
18、ward out side 2 & 3：toward inside,Muslimov & Harding, 2003,Slot gap model,Beams in ICS model,Type I,Type II,Qiao,Liu,Zhang & Han, 2001,Obs. & ICS : Type I a,Obs.,ICS,Qiao,Liu, Zhang,& Han, 2001,AA,Lyne & Manchester (1988) & Sieber et al. (1975),Obs. & ICS: Type Ib,Obs.,ICS,Qiao,Liu, Zhang,& Han, 200
19、1,AA,Kramer (1994).,Obs. & ICS : Type IIa,ICS,Obs.,Qiao,Liu, Zhang,& Han, 2001,AA,Phillips & Wolszczan (1992).,Magnetospere of pulsars,Am-mass of ion, Z-charge of ion,Outer gap, 1,Space charge limited flow,Inner gap,Holloway 1975 MN,Poln. of Individual pulses in ICS model,Xu,Liu,Han,Qiao, 2000, ApJ,
20、Radio emission of pulsars,Observations & TheoriesEmission beams:Core+ConesEmission locationsPolarization: linear, circular, “orthogonal mode”Pulse profiles changing with frequencies,Rankin (1983, 1993),Gil ,Gangadhara & Gupta 2001,Lyne & Manchester 1988,Han & Manchester 2001,Core and Cones,=220(1-Co
21、si),ICS model: The low frequency wave canPropagate near the surface,Qiao & Lin, 1998, AA,Polar Cap Model,Inner annular gap,Qiao,Lee,Wang,Xu, 2003,Gamma-ray +radio emission,Radio + Gamma ray emission model Basic picturePulse profiles fitting: radio + Gamma-rays,Gamma-ray emission of pulsars,Current m
22、odels Polar cap model Outer gap model Radio + Gamma ray emission model Basic picturePulse profiles fitting: radio + Gamma-rays,Pulsars are broad-band emitters (gamma-ray, X-ray, optical, radio) Pulsars must be particle accelerators Two preferred acceleration regions:- Polar cap region- Outer gap region,Pulsar Gaps,Gamma-ray OBS. Of Radio Pulsars,Janssenet al. astr-ph/0406484: PSR B1818-13,
