White dwarf pulsars as possible cosmic ray electron-positron factories
- Department of Physics, Kyoto University, Kyoto 606-8502 (Japan)
We suggest that white dwarf (WD) pulsars can compete with neutron star (NS) pulsars for producing the excesses of cosmic ray electrons and positrons (e{sup {+-}}) observed by the PAMELA, ATIC/PPB-BETS, Fermi, and H.E.S.S. experiments. A merger of two WDs leads to a rapidly spinning WD with a rotational energy ({approx}10{sup 50} erg) comparable to the NS case. The birth rate ({approx}10{sup -2}-10{sup -3}/yr/galaxy) is also similar, providing the right energy budget for the cosmic ray e{sup {+-}}. Applying the NS theory, we suggest that the WD pulsars can in principle produce e{sup {+-}} up to {approx}10 TeV. In contrast to the NS model, the adiabatic and radiative energy losses of e{sup {+-}} are negligible since their injection continues after the expansion of the pulsar wind nebula, and hence it is enough that a fraction {approx}1% of WDs are magnetized ({approx}10{sup 7}-10{sup 9} G) as observed. The long activity also increases the number of nearby sources ({approx}100), which reduces the Poisson fluctuation in the flux. The WD pulsars could dominate the quickly cooling e{sup {+-}} above TeV energy as a second spectral bump or even surpass the NS pulsars in the observing energy range {approx}10 GeV-1 TeV, providing a background for the dark matter signals and a nice target for the future AMS-02, CALET, and CTA experiment.
- OSTI ID:
- 21503920
- Journal Information:
- Physical Review. D, Particles Fields, Vol. 83, Issue 2; Other Information: DOI: 10.1103/PhysRevD.83.023002; (c) 2011 American Institute of Physics; ISSN 0556-2821
- Country of Publication:
- United States
- Language:
- English
Similar Records
Discriminating different scenarios to account for the cosmic e{sup {+-}} excess by synchrotron and inverse Compton radiation
Utilizing cosmic-ray positron and electron observations to probe the averaged properties of Milky Way pulsars
Related Subjects
COSMOLOGY AND ASTRONOMY
COOLING
COSMIC ELECTRONS
COSMIC POSITRONS
COSMIC RADIATION
COSMIC RAY SOURCES
ECOSYSTEMS
ENERGY BALANCE
EXPANSION
FLUCTUATIONS
GALAXIES
GEV RANGE
INJECTION
NEBULAE
NEUTRON STARS
NONLUMINOUS MATTER
PARTURITION
PULSARS
WHITE DWARF STARS
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
COSMIC RADIO SOURCES
DWARF STARS
ELECTRONS
ELEMENTARY PARTICLES
ENERGY RANGE
FERMIONS
INTAKE
IONIZING RADIATIONS
LEPTONS
MATTER
POSITRONS
RADIATIONS
SECONDARY COSMIC RADIATION
STARS
VARIATIONS