pulsar — LLMpedia

pulsar
Name	Pulsar
Type	Neutron star
Mass	~1.4–2.3 M☉
Radius	~10–15 km
Discovered	1967
Discoverer	Jocelyn Bell Burnell; Antony Hewish

Contents

pulsar Pulsars are rapidly rotating, highly magnetized compact star remnants that emit beams of electromagnetic radiation detectable as periodic pulses. First identified in 1967 by Jocelyn Bell Burnell and analyzed by Antony Hewish, pulsars have become central objects for studies by observatories such as Arecibo Observatory, Parkes Observatory, and Very Large Array teams. Their properties link research programs at institutions like Harvard–Smithsonian Center for Astrophysics, Max Planck Institute for Radio Astronomy, and missions including Fermi Gamma-ray Space Telescope and Chandra X-ray Observatory. Pulsars inform models developed by theorists affiliated with Princeton University, Cambridge University, and California Institute of Technology.

Introduction

Pulsars are a subclass of compact star phenomena related to remnants observed after Core-collapse supernova events such as those cataloged by the Supernova Legacy Survey and studied in remnants like Crab Nebula and Cassiopeia A. Observational programs using instruments like the Green Bank Telescope, LOFAR, MeerKAT, and Square Kilometre Array precursor arrays have expanded known populations cataloged by groups at Jodrell Bank Observatory and the European Space Agency. Historic campaigns, including surveys by Swinburne University of Technology and collaborations like the International Pulsar Timing Array, have improved detection rates. Pulsars bridge work by researchers at establishments such as Massachusetts Institute of Technology and University of Manchester.

Pulsars form from the collapsed cores of massive progenitors in events studied by teams at Los Alamos National Laboratory and Lawrence Berkeley National Laboratory and modeled with codes developed at Oak Ridge National Laboratory and Princeton Plasma Physics Laboratory. The internal structure includes a crust and superfluid core as predicted by nuclear physics groups at CERN and RIKEN, and equations of state explored by researchers at University of Illinois Urbana-Champaign and University of Arizona. Rotation rates and moment of inertia constraints are compared to mass measurements from binaries studied by W. M. Keck Observatory and Hubble Space Telescope programs. Magnetic field studies draw on theory from scientists affiliated with University of Cambridge, University of Oxford, and Columbia University.

Emission models for pulsars incorporate coherent radio processes, curvature radiation, and magnetospheric particle acceleration investigated by researchers at Stanford University, University of California, Berkeley, and University of Tokyo. High-energy gamma-ray and X-ray emissions have been analyzed via data from Fermi Gamma-ray Space Telescope and XMM-Newton teams, while optical counterparts were characterized using Keck Observatory and Very Large Telescope observations. Plasma physics labs at Princeton University and Imperial College London contribute to theories of pair production and magnetospheric gaps with links to work by John M. Cordes, Scott Ransom, and Andrei Gruzinov. Models integrate contributions from landmark papers published through Physical Review Letters and Astrophysical Journal collaborations.

Pulsars are classified into types such as radio pulsars, millisecond pulsars, magnetars, and intermittent pulsars using surveys by Parkes Observatory, Arecibo Observatory, and FAST teams. Millisecond pulsars in globular clusters like 47 Tucanae and systems such as PSR B1937+21 were discovered in studies led by D. C. Backer and Frederick A. Rasio. Magnetar behavior links to objects observed by Swift Observatory and catalogs maintained by NASA, with notable sources including SGR 1806−20 and Anomalous X-ray Pulsar 1E 2259+586 studied by groups at Caltech and University College London. Binary pulsars such as PSR B1913+16 and PSR J0737−3039A/B provided tests pursued by researchers at Cornell University, Rutherford Appleton Laboratory, and Max Planck Society.

Pulsar timing precision achieved by arrays like the North American Nanohertz Observatory for Gravitational Waves and European Pulsar Timing Array enables experiments in gravitational physics, including constraints on gravitational wave backgrounds sought by the Laser Interferometer Gravitational-Wave Observatory and theoretical input from Albert Einstein Institute. Timing has measured orbital decay consistent with predictions from Albert Einstein's general theory of relativity and informed work by Joseph Taylor Jr. and Russell Hulse, recipients of the Nobel Prize in Physics. Applications extend to tests of dense-matter physics by groups at Argonne National Laboratory and to searches for planetary companions akin to discoveries by teams at University of California, Santa Cruz.

Pulsar life cycles involve spin-down, accretion-driven recycling in low-mass X-ray binaries observed by RXTE and NICER, and transitions to magnetar-like states as studied by researchers at NASA Goddard Space Flight Center and European Space Agency laboratories. End states include conversion to radio-quiet neutron stars, collapse to black holes in scenarios examined by LIGO Scientific Collaboration and conceptualized by theorists at Kavli Institute for Theoretical Physics, or long-term cooling tracked by observatories like Chandra X-ray Observatory. Evolutionary pathways link to population syntheses performed by groups at Max Planck Institute for Astrophysics and surveys such as those run by Sloan Digital Sky Survey.

Category:Stars