A Search for Pulsed Radio Emission from X-ray Dim Isolated Neutron Stars at Decameter Wavelenghts

Abstract

Our work mainly deals with searching for the radio emission of x-ray dim isolated neutron stars (XDINS) at decameter wavelengths seeing that discrepant data about presence or absence of pulse radiation from them have appeared. The reasons for the search experiment performance became the installation of a new broadband high-sensitivity receiver with a high dynamic range at the UTR-2 radiotelescope and development of the software package for pulse and repetitive radiation search. The results obtained give no ground to speak about the presence of pulse radiation from sources 1RXS J1308+21 and 1RXS J2143+06 at a level above 4σ, σ=2.5 mJy. This can be explained by both absence of radiation and an inverse spectrum slope at low frequencies or signal characteristics changing. High sensitivity of the experiment and developed package of search programs is proved by confident detection (>10σ) of a “test” weak pulsar B1508+55 which has never been detected at decameter waves.