Now showing items 1-4 of 4

    • Chaplygin-gas solutions of f(R) gravity 

      Elmardi, Maye; Abebe, Amare; Tekola, Abiy (World Scientific Publishing, 2016)
      We explore exact f(R) gravity solutions that mimic Chaplygin-gas inspired CDM cosmology. Starting with the original, generalized and modified Chaplygin gas equations of state, we reconstruct the forms of f(R) Lagrangians. ...
    • H.E.S.S. constraints on dark matter annihilations towards the Sculptor and Carina dwarf galaxies 

      Abramowski, A.; Büsching, I.; De Jager, O.C.; Venter, C.; Vorster, M. (Elsevier, 2011)
      The Sculptor and Carina dwarf spheroidal galaxies were observed with the H.E.S.S. Cherenkov telescope array between January 2008 and December 2009. The data sets consist of a total of 11.8 h and 14.8 h of high quality data, ...
    • H.E.S.S. observations of the globular clusters NGC 6388 and M15 and search for a dark matter signal 

      Abramowski, A.; Büsching, I.; De Jager, O.C.; Venter, C.; Vorster, M. (IOP Publishing, 2011)
      Observations of the globular clusters (GCs) NGC 6388 and M15 were carried out by the High Energy Stereoscopic System array of Cherenkov telescopes for a live time of 27.2 and 15.2 hr, respectively. No gamma-ray signal is ...
    • Search for dark matter annihilation signals from the fornax galaxy cluster with HESS 

      Abramowski, A.; Büsching, I.; De Jager, O.C.; Sheidaei, F.; Venter, C.; Vorster, M. (IOP Publishing, 2012)
      The Fornax galaxy cluster was observed with the High Energy Stereoscopic System for a total live time of 14.5 hr, searching for very high energy (VHE; E > 100GeV) γ -rays from dark matter (DM) annihilation. No significant ...