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Title: ON THE ORIGIN OF RADIO EMISSION FROM MAGNETARS

Magnetars are the most magnetized objects in the known universe. Powered by the magnetic energy, and not by the rotational energy as in the case of radio pulsars, they have long been regarded as a completely different class of neutron stars. The discovery of pulsed radio emission from a few magnetars weakened the idea of a clean separation between magnetars and normal pulsars. We use the partially screened gap (PSG) model to explain radio emission of magnetars. The PSG model requires that the temperature of the polar cap is equal to the so-called critical value, i.e., the temperature at which the thermal ions outflowing from the stellar surface screen the acceleration gap. We show that a magnetar has to fulfill the temperature, power, and visibility conditions in order to emit radio waves. First, in order to form PSG, the residual temperature of the surface has to be lower than the critical value. Second, since the radio emission is powered by the rotational energy, it has to be high enough to enable heating of the polar cap by backstreaming particles to the critical temperature. Finally, the structure of the magnetic field has to be altered by magnetospheric currents in order tomore » widen a radio beam and increase the probability of detection. Our approach allows us to predict whether a magnetar can emit radio waves using only its rotational period, period derivative, and surface temperature in the quiescent mode.« less
Authors:
; ;  [1]
  1. Kepler Institute of Astronomy, University of Zielona Góra, Lubuska 2, 65-265 Zielona Góra (Poland)
Publication Date:
OSTI Identifier:
22364200
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 800; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACCELERATION; CRITICAL TEMPERATURE; DETECTION; MAGNETIC FIELDS; NEUTRON STARS; NEUTRONS; ORIGIN; PULSARS; PULSES; RADIOWAVE RADIATION; STELLAR MAGNETOSPHERES; SURFACES; UNIVERSE