An Approach for Estimating the Deformation of Pulsar Included in Binary-System PSR B 1913+16

M. Soleiman, Mohammed Hasan; Elgogary, Magdi Mohamed; Abdel-AZIZ Saleh, Sayed Saleh; Omar, Ahmed Imsaery

doi:10.21608/ejphysics.2018.6174.1015

An Approach for Estimating the Deformation of Pulsar Included in Binary-System PSR B 1913+16

Document Type : Original Article

Authors

¹ Physics Department, Faculty of Science, Cairo University, Giza, Egypt.

² Physics Department, Faculty of Science, Cairo University, Giza 12613, Egypt.

³ Physics Department, Faculty of Science, Cairo University, Giza 12613, Egypt, and Physics Department, Faculty of Science, Sebha University, Sebha, Libya.

10.21608/ejphysics.2018.6174.1015

Abstract

Discovery of pulsars included in binary systems (BS) is dated to 1974, when Hulse and Taylor announced the parameters of pulsar PSR B 1913+16. It inspires great motivations for possible new physical measurements of the properties of neutron stars (NSs). We present a simple model to estimate the deformation in shape of two neutron stars bounded to each other in a binary system due to their mutual gravity. The model predicts the Bulk modulus of the pulsar – as an infinite nuclear matter. In particular, the model determines the stress and the strain of a pulsar included in PSR B 1913+16 binary system within the frame of Newtonian theory of gravity. The calculations show that, our approach is consistent with the model of two spherical neutron stars up to the eccentricity-squared. The model could evaluate the axial elongation of the observed NS as well as the eccentricity. The eccentricity is found to be of order 10^(-5) and the elongation is of the order 10^(-9) km.

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