An accreting pulsar with extreme properties drives an ultraluminous x-ray source in NGC 5907
- Others:
- Israel, G. L.
- Belfiore, A.
- Stella, L.
- Esposito, P.
- Casella, P.
- De Luca, A.
- Marelli, M.
- Papitto, A.
- Perri, M.
- Puccetti, S.
- Rodriguez Castillo, G. A.
- Salvetti, D.
- Tiengo, A.
- Zampieri, L.
- D'Agostino, D.
- Greiner, J.
- Haberl, F.
- Novara, G.
- Salvaterra, R.
- Turolla, R.
- Watson, M.
- Wilms, J.
- Wolter, A.
Description
Ultraluminous x-ray sources (ULXs) in nearby galaxies shine brighter than any x-ray source in our Galaxy. ULXs are usually modeled as stellar-mass black holes (BHs) accreting at very high rates or intermediate-mass BHs.We present observations showing that NGC 5907 ULX is instead an x-ray accreting neutron star (NS) with a spin period evolving from 1.43 seconds in 2003 to 1.13 seconds in 2014. It has an isotropic peak luminosity of ∼ 1000 times the Eddington limit for a NS at 17.1 megaparsec. Standard accretion models fail to explain its luminosity, even assuming beamed emission, but a strong multipolar magnetic field can describe its properties. These findings suggest that other extreme ULXs (x-ray luminosity ≥ 1041 erg second-1) might harbor NSs.
Additional details
- URL
- http://hdl.handle.net/11567/1087379
- URN
- urn:oai:iris.unige.it:11567/1087379
- Origin repository
- UNIGE