Letter to the Editor
INTEGRAL high energy observations of 2S 0114+65
LUTh, Observatoire de Paris, 92195 Meudon Cedex, France e-mail: email@example.com
2 CEA Saclay, DSM/DAPNIA/Service d'Astrophysique (CNRS FRE 2591), 91191 Gif-sur-Yvette, France
Accepted: 28 April 2005
We report the first INTEGRAL timing and spectral analysis of the high mass X-ray binary source 2S 0114+65 at high energies (5–100 keV). The pulse period was found at 2.668 h with a high pulsed fraction, ~80% in both the 20–40 keV and 40–80 keV energy bands. The spin-up trend over ~8 years was measured to be 10-7 s s-1. The hard X-ray spectrum obtained with JEM-X/ISGRI is well described by a high energy exponential cut-off power law model where the estimated luminosity is 1.8 1036 erg s-1 in the 5–100 keV energy band, for a source distance of 7.2 kpc. We tentatively identify a cyclotron resonance scattering feature at ~22 keV with one harmonic, implying a magnetic field of ~2.5 1012 G.
Key words: pulsars: individual: 2S 0114+65 / stars: neutron / X-rays: stars
© ESO, 2005