Determination of the geometry of the PSR B1913+16 system by geodetic precession

Abstract

New observations of the binary pulsar B1913+16 are presented. Since 1978 the leading component of the pulse profile has weakend dramatically by about 40%. For the first time, a decrease in component separation is observed, consistent with expectations of geodetic precession. Assuming the correctness of general relativity and a circular hollow-cone like beam, a fully consistent model for the system geometry is developed. The misalignment angle between pulsar spin and orbital momentum is determined giving direct evidence for an asymmetric kick during the second supernova explosion. It is argued that the orbital inclination angle is $132\fdg8$ (rather than $47\fdg2$). A prediction of this model is that PSR B1913+16 will not be observable anymore after the year 2025.