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Magnetars: wind braking H. Tong Xinjiang Astronomical Observatory Traditional magnetar model Magnetar = young NS (SNR MSC) Bdip BQED=4.4×1013 G (braking) Bmul=1014 -1015 G (burst and super-Eddington luminosity and persistent emission) “Magnetic dipole braking” of normal pulsars Rotational energy?magnetic dipole radiation+particle wind (rotation-powered) Effects: higher order modifications, e.g. braking index (Michel 1969; Manchester 1985; Xu Qiao 2001; Contopoulos Spitkovsky 2006; Wang+ 2012)timing noise (Lyne+ 2010; Liu+ 2011)+a rotation-powered PWN Exist: intermittent pulsars (Kramer+ 2006; Camilo+ 2012) Magnetic dipole braking is only a pedagogical model! Rotating dipole in vaccum! Only as first order approximation to the real case Normal pulsars braked down by a rotation-powered particle wind Existence of a particle wind in magnetars Varying period derivative Higher level of timing noise (compared with HBPSRs) Magnetism-powered PWN Correlation between Lpwn and Lx Higher Lpwn/Edot Rotational energy loss rate In summary Magnetism-powered particle wind When Lp Edot, a much lower magnetic field (plus higher order effects, magnetar case) Dipole magnetic field (1): magnetic dipole braking Dipole magnetic field (2): wind braking Conclusions (1) Wind braking: Wind-aided spin down A lower surface dipole field Magnetars=NS+strong multipole field Explain challenging observations of magnetars Their SNe energies are of normal value Non-detection of magnetars by Fermi-LAT The problem of low-B SGRs The relation between magnetars and HBPSRs A decreasing Pdot during magnetar outburst Low luminosity mangetars more likely to have radio emissons Two predictions A magentism-powered PWN A braking index n3 Conclusions (2): subsequent developments Magnetism-powered pulsar wind nebula around SGR Swift J1834.9-0846 (Younes et al. 2012) Geometrical effect during wind braking:small inclination angle-- higher B(Tong Xu 2012) A paradigm shift in the future? FAST: more ra