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The discovery of the white dwarf binary system AR Scorpii (AR Sco) with itsfascinating non-thermal dominated multi-frequency emission has sparked renewedinterest in potential high energy gamma-ray emission from white dwarf pulsars.The Spectral Energy Distribution (SED) below and above optical shows evidenceof non-thermal synchrotron emission, with pulsed emission in optical and X-raybands at the white dwarf spin period ($P_{*} = 117 \, \mbox{s}$) as well as abeat period ($P_{\rm b} = 118.1 \, \mbox{s}$) with the binary period. From anenergy perspective, the highly magnetic rotating white dwarf can accelerateparticles to TeV energies. In this study, a search for high energy gamma-rayemission was conducted between 100 MeV - 500 GeV by analysing the newlyavailable Fermi-LAT Pass 8 data with the new Fermi 1.0.1 Science Tools. Binnedlikelihood analysis was done using power law, broken power law and log parabolamodels. From the selected Region of Interest (ROI) centred on AR Sco'sposition, we calculated a significance of $\sqrt{TS}\leq$ 3.87$\sigma$ for theintegrated gamma-ray activity between 100 MeV - 500 GeV at a photon flux levelof 0.486 $\pm$ 0.261 x 10$^{-8}$ photons cm$^{-2}$ s$^{-1}$ using the brokenpower law model. This resulted in a 3$\sigma$ upper-limit detection from theposition of AR Sco. The location of AR Sco inside the Rho Ophiuchi (Rho Oph)molecular cloud complex combined with the poor spatial resolution of Fermi-LAT,complicates any positive identification of low-level gamma-ray activity at thelocation that coincides with the position of AR Sco.

Results from the long-term Fermi-LAT observations of the white dwarf binary pulsar AR Scorpii