TY - JOUR
T1 - Origin of Pulsar Radio Emission
AU - Philippov, Alexander
AU - Timokhin, Andrey
AU - Spitkovsky, Anatoly
N1 - Funding Information:
The authors would like to thank J. Arons, A. Beloborodov, V. Beskin, A. Jessner, and Yu. Lyubarsky for numerous insightful discussions. A. P. and A. S. acknowledge hospitality of KITP, where part of this work was performed. This work was supported by NASA Grant No. 80NSSC18K1099 and by the National Science Foundation under Grants No. NSF AST-1616632 and No. NSF PHY-1748958. Resources supporting this work were provided by the NASA High-End Computing Program through the NASA Advanced Supercomputing Division at Ames Research Center. Research at the Flatiron Institute is supported by the Simons Foundation, which also supported A. S. (Grant No. 267233). We also thank the anonymous referees for valuable comments on the Letter.
Publisher Copyright:
© 2020 American Physical Society.
PY - 2020/6/19
Y1 - 2020/6/19
N2 - Since pulsars were discovered as emitters of bright coherent radio emission more than half a century ago, the cause of the emission has remained a mystery. In this Letter we demonstrate that coherent radiation can be directly generated in nonstationary pair plasma discharges which are responsible for filling the pulsar magnetosphere with plasma. By means of large-scale two-dimensional kinetic plasma simulations, we show that if pair creation is nonuniform across magnetic field lines, the screening of electric field by freshly produced pair plasma is accompanied by the emission of waves which are electromagnetic in nature. Using localized simulations of the screening process, we identify these waves as superluminal ordinary (O) modes, which should freely escape from the magnetosphere as the plasma density drops along the wave path. The spectrum of the waves is broadband and the frequency range is comparable to that of observed pulsar radio emission.
AB - Since pulsars were discovered as emitters of bright coherent radio emission more than half a century ago, the cause of the emission has remained a mystery. In this Letter we demonstrate that coherent radiation can be directly generated in nonstationary pair plasma discharges which are responsible for filling the pulsar magnetosphere with plasma. By means of large-scale two-dimensional kinetic plasma simulations, we show that if pair creation is nonuniform across magnetic field lines, the screening of electric field by freshly produced pair plasma is accompanied by the emission of waves which are electromagnetic in nature. Using localized simulations of the screening process, we identify these waves as superluminal ordinary (O) modes, which should freely escape from the magnetosphere as the plasma density drops along the wave path. The spectrum of the waves is broadband and the frequency range is comparable to that of observed pulsar radio emission.
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U2 - 10.1103/PhysRevLett.124.245101
DO - 10.1103/PhysRevLett.124.245101
M3 - Article
C2 - 32639807
AN - SCOPUS:85087697285
SN - 0031-9007
VL - 124
JO - Physical Review Letters
JF - Physical Review Letters
IS - 24
M1 - 245101
ER -