Neutron star between 10 and 10 (100 million to 1 quadrillion) times as strong as that of the Earth. The gravitational field at the neutron star's surface is about (200 billion) times that of the Earth. As the star's core collapses, its rotation rate increases as a result of conservation of angular momentum, hence newly formed neutron stars rotate at up to several hundred times per second. Some neutron stars emit beams of electromagnetic radiation that make them detectable as pulsars. Indeed, the discovery of pulsars by Jocelyn Bell Burnell in 1967 was the first observational suggestion that neutron stars exist. The
Beam spoiler Beam spoiler A beam spoiler is a piece of material, placed into the path of the photon beam in radiotherapy. The purpose of the spoiler is to reduce the depth of the maximum radiation dosage. The beam spoiler is composed of a sheet of material which has a low atomic number, typically lucite, the thickness of which is varied according to the beam energy and the distance by which the radiation dose must be shifted. As the primary photon beam passes through the plate, secondary electrons are generated. The beam exiting the spoiler is a combination of the spoiler-attenuated photons