Contribution of pulsars to the gamma-ray background and their observation with the space telescopes GLAST and AGILE

E. Bisesi

doi:10.1007/1-4020-4339-2_45

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Contribution of pulsars to the gamma-ray background and their observation with the space telescopes GLAST and AGILE

E. Bisesi

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Abstract

Luminosities and uxes of the expected population of galactic gamma-ray pulsars become foreseeable if physical distributions at birth and evolutive history are assigned. In this work we estimate the contribution of pulsar uxes to the gamma-ray background, which has been measured by the EGRET experiment on board of the CGRO. For pulsar luminosities we select some of the most important gamma-ray emission models, taking into account both polar cap and outer gap scenarios. We nd that this contribution strongly depends upon controversial neutron star birth properties. A comparison between our simulation results and EGRET data is presented for each model, nding an average contribution of about 10%. In addition, we perform the calculation of the number of new gamma-ray pulsars detectable by GLAST and AGILE, showing a remarkable di erence between the two classes of models. Finally, we suggest some improvements in the numerical code, including more sophisticated galactic m odels and di erent populations of pulsars like binaries, milliseconds, anomalous pulsars and magnetars.

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E. Bisesi. 2005-03-24. Contribution of pulsars to the gamma-ray background and their observation with the space telescopes GLAST and AGILE. https://doi.org/10.1007/1-4020-4339-2_45

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