出版社：SISSA, Scuola Internazionale Superiore di Studi Avanzati
摘要：Neutron stars generate powerful winds of relativistic particles that form bright synchrotron nebulae
around them. Polarimetry provides a unique insight into the geometry and magnetic configuration
of the wind, but high-energy measurements have failed until recently. The Integral-IBIS
telescope has been used in its Compton mode to search for linearly polarized emission for energies
above 200 keV from the Crab nebula. The asymmetries in the instrument response are small
and we obtain evidence for a strongly polarized signal at an angle parallel to the pulsar rotation
axis. This result confirms the detection recently reported by Dean et al. (2008), and extends the
polarization measure for all the pulsar’s phases. The hard X-ray/soft g -ray observations therefore
probe the inner jets or equatorial flow of the wind. The achieved sensitivity opens a new window
for polarimetric studies at energies above 200 keV.
