The Structure and Signals of Neutron Stars, from Birth to Death

New multiwavelength observations of two gamma-ray pulsars J0357+3205 and J1357-6429

28 Mar 2014, 17:00

15m

Evening session - Parallel B

Speaker

Ms Aida Kirichenko (Ioffe Physical Technical Institute)

Description

Recent discoveries of the Fermi mission have increased the number of known gamma-ray pulsars by a factor of twenty. Multiwavelength investigations of these objects are crucial for unveiling the pulsar emission nature. Because gamma-ray pulsars are typically nearby and energetic, they, in particular, appear to be promising targets for studies in X-ray and optical domains. We present new observations of two gamma-ray pulsars J0357+3205 and J1357-6429 obtained with GTC/OSIRIS and VLT/NACO facilities. We also performed an independent analysis of the archival X-ray data obtained with XMM-Newton/EPIC and Chandra/ACIS. For the radio quiet pulsar J0357+3205 we set a deep upper limit g>28.1 on its brightness in the optical and compare it with the X-ray data. The upper limit implies that the optical nonthermal power-law emission of the pulsar is about two orders of magnitude lower than it was expected from the X-ray data and suggests a spectral break in the pulsar nonthermal spectrum between the optical and X-rays. At the same time the optical upper limit is consistent with the upper limit on the temperature of the neutron star entire surface of 40 eV followed from the X-ray data, making it one of the coldest among cooling middle-aged neutron stars known and a promising target for observations in the UV. For the pulsar J1357-6429 we present new adaptive-optical near-IR observations and discuss possible counterpart candidates of the object. New radio interferometric ATCA observations are also presented. They allow us to put new constraints on the pulsar proper motion.