Now showing items 1-4 of 4

    • Evolution of the spin, spectrum and super-orbital period of the ultraluminous X-ray pulsar M51 ULX7 

      Brightman, Murray; Bachetti, Matteo; Earnshaw, Hannah; Fürst, Felix; Heida, Marianne; Israel, Gian Luca; Pike, Sean; Stern, Daniel; Walton, Dominic J (2022-01-21)
      M51 ULX7 is among a small group of known ultra luminous X-ray pulsars (ULXPs). The neutron star powering the source has a spin period of 2.8 s, orbits its companion star with a period of 2 days, and a super orbital period ...
    • The Orbit of NGC 5907 ULX-1 

      Belfiore, Andrea; Salvaterra, Ruben; Sidoli, Lara; Israel, Gian Luca; Stella, Luigi; De Luca, Andrea; Mereghetti, Sandro; Esposito, Paolo; Pintore, Fabio; D’Aì, Antonino; Rodrìguez Castillo, Guillermo; Walton, Dominic J.; Fürst, Felix; Magistrali, Danilo; Wolter, Anna; Imbrogno, Matteo (2024-04-09)
      We report on the orbit of the binary system powering the most extreme ultraluminous X-ray pulsar known to date: NGC 5907 ULX-1 (hereafter ULX1). ULX1 has been the target of a substantial multi-instrument campaign, mainly ...
    • Orbital Decay in M82 X-2 

      Bachetti, Matteo; Heida, Marianne; Maccarone, Thomas; Huppenkothen, Daniela; Israel, Gian Luca; Barret, Didier; Brightman, Murray; Brumback, McKinley; Earnshaw, Hannah P.; Forster, Karl; Fürst, Felix; Grefenstette, Brian W.; Harrison, Fiona A.; Jaodand, Amruta D.; Madsen, Kristin K.; Middleton, Matthew; Pike, Sean N.; Pilia, Maura; Poutanen, Juri; Stern, Daniel; Tomsick, John A.; Walton, Dominic J.; Webb, Natalie; Wilms, Jörn (2022-10-05)
      M82 X-2 is the first pulsating ultraluminous X-ray source discovered. The luminosity of these extreme pulsars, if isotropic, implies an extreme mass transfer rate. An alternative is to assume a much lower mass transfer ...
    • Probing the nature of the low state in the extreme ultraluminous X-ray pulsar NGC 5907 ULX1 

      Fuerst, F.; Walton, D. J.; Israel, Gian Luca; Bachetti, M.; Barret, D.; Brightman, Murray; Earnshaw, H. P.; Fabian, A.; Heida, M.; Imbrogno, M.; Middleton, M. J.; Pinto, C.; Salvaterra, R.; Roberts, T. P.; Castillo, G. A. Rodríguez; Webb, N. (2023-04-12)
      NGC 5907 ULX1 is the most luminous ultra-luminous X-ray pulsar (ULXP) known to date, reaching luminosities in excess of 1041 erg s-1. The pulsar is known for its fast spin-up during the on-state. Here, we present a long-term ...