Synchro-Curvature Self Compton Radiation Bo Zhang & Zi-Gao Dai Department of Astronomy, Nanjing University

Outline Background Basic scheme & equations Sample results Conclusions 2019/7/14 Kyoto 2010

Background “Traditional” high energy radiation mechanisms: Synchrotron radiation Curvature radiation Inverse Compton scattering On synchro-curvature radiation: Proposed by Cheng & Zhang in mid-1990s (e.g. Cheng & Zhang 1996) Electrons moving around curved field lines Synchrotron and curvature radiations as two limits Already be applied to pulsars & GRBs 2019/7/14 Kyoto 2010

Basic Schemes of Magnetic Fields Synchrotron radiation Curvature radiation Synchro-curvature radiation and corresponding self Compton scattering B B 2019/7/14 Kyoto 2010

Basic Equations Synchro-curvature seed spectrum: Self Compton scattering: 2019/7/14 Kyoto 2010

Basic Assumptions Circular magnetic field Spiral trajectory around circular field lines Guiding center on field lines Decrease of velocity ignored Drifts of electrons ignored Isotropic distribution of electrons 2019/7/14 Kyoto 2010

Calculation Results p=5 p=2.5 2019/7/14 Kyoto 2010

Results With Cooling Effects Fast cooling Slow cooling 2019/7/14 Kyoto 2010

Results With KN Cutoff Considered 2019/7/14 Kyoto 2010

Conclusions The synchro-curvature self Compton emission could differ from SSC radiation in Thompson regime Larger p, larger deviation Cooling effects may change the resulting spectrum KN cutoff may make the deviation between SSC and synchro-curvature self Compton smaller 2019/7/14 Kyoto 2010

Possible Applications High energy radiation from pulsars, AGNs, etc… GRBs? Synchro-curvature radiation already be used to interpret high energy turnoffs High energy turnoff as well as cutoff? (e.g. GRB 090926 A, see Ohno’s talk) Problem: Large p required; physics of particle acceleration? GRB 930131 GRB 910503 Deng et al. 2005 2019/7/14 Kyoto 2010