Ambiguity of converting phase-averaged flux into luminosity for millisecond pulsars in gamma rays

TL;DR

This paper investigates how using phase-averaged flux to estimate gamma-ray luminosity of millisecond pulsars can lead to significant over- or underestimation, depending on viewing angles and energy bands.

Contribution

It introduces a numerical modeling approach to quantify the discrepancy between actual and pseudo luminosity estimates for millisecond pulsars in gamma rays.

Findings

The ratio L_{pseudo}/L_{actual} varies with viewing angle.

Discrepancies are significant in Fermi GST and H.E.S.S. II energy bands.

The study highlights potential biases in luminosity estimation methods.

Abstract

We study a magnitude of possible over/underestimation of the actual gamma-ray luminosity L_{actual} of a millisecond pulsar when using so-called pseudo luminosity L_{pseudo} which is inferred from a phase-averaged flux. Both, L_{actual} and L_{pseudo} are calculated with the numerical code thatmodels the millisecond pulsar magnetospheric activity in the space charge limited flow approximation with unscreened accelerating electric field. The behaviour of L_{pseudo}/L_{actual} depending on viewing angle is analysed in the energy bands corresponding to the operational energy bands of Fermi GST and H.E.S.S. II.