Is PSR J0855−4644 responsible for the 1.4 TeV electron spectral bump hinted by DAMPE?

Abstract

DAMPE observation on the cosmic ray electron spectrum hints a narrow excess at ∼1.4 TeV. Although the excess can be ascribed to dark matter particles, pulsars and pulsar wind nebulae are believed to be a more natural astrophysical origin: electrons injected from nearby pulsars at their early ages can form a bump-like feature in the spectrum due to radiative energy losses. In this paper, with a survey of nearby pulsars, we find 4 pulsars that may have notable contributions to ∼1.4 TeV cosmic ray electrons. Among them, PSR J0855−4644 has a spin down luminosity more than 50 times higher than others and presumably dominates the electron fluxes from them. X-ray observations on the inner compact part (which may represent a tunnel for the transport of electrons from the pulsar) of PWN G267.0−01.0 are then used to constrain the spectral index of high energy electrons injected by the pulsar. We show that high-energy electrons released by PSR J0855−4644 could indeed reproduce the 1.4 TeV spectral feature hinted by the DAMPE with reasonable parameters.

Research on electron and positron spectrum in the high-energy region based on the gluon condensation model

“…The CRs with energies above 1 TeV usually come from distances within 1 kpc from the solar system, highlighting the importance of nearby sources as detection targets. The energy spectra of CRs may be influenced by nearby sources such as pulsar wind nebulae (PWNe) [6][7][8][9][10][11][12], supernova remnants (SNRs) [6,[13][14][15][16][17][18], and dark matter (DM) particle annihilation or decay [19][20][21][22][23][24][25]. A commonly accepted idea is that the detected spectrum should be a combination of contributions originating from background and local SNR sources.…”