Pulsars and neutron stars/Introduction

Introduction Pulsars are highly magnetized, rapidly rotating neutron stars. They are also astrophysical laboratories for the study of extreme physics. This wiki-book describes the observational and theoretical research relating to such stars. There's no doubt that pulsars and neutron stars are intrinsically interesting. Representing an end-state of stellar evolution, they are incredibly dense and have huge magnetic fields. Neutron stars can be observed in order to study electrodynamics and plasma processes within highly magnetized media or to study quantum and particle physics in the superconducting superfluid of their interiors. Pulsars are (usually) detected by the regular sequence of pulses they emit. Pulsars creating very stable pulsed signals are observed in the hope of making a direct detection of gravitational waves and also to search for irregularities in terrestrial time standards. Pulsars in binary systems are a unique means of studying theories of gravitation in the strong-field limit. They have also been used to probe the electron density distribution in the interstellar medium and globular clusters, to study the size and direction of the Galactic magnetic field and to determine the gravitational potential of the Galaxy and globular clusters. Pulsar observations have also led to measurements of the mass of solar system objects and to search for unknown objects in our solar system. The first extrasolar planets to be discovered were orbiting a pulsar. A new generation of telescopes and instrumentation will soon revolutionize pulsar astronomy. With luck, within a few years, pulsar astronomers will be studying gravitational waves in detail, probing gravity by studying pulsars orbiting black holes and analyzing the population of pulsars in distant galaxies. In the not too distant future it is also possible that spacecraft will be navigating their way through our solar system by means of pulsar observations. The aim of this wikibook There are many excellent text books about pulsars and neutron stars, including: The Handbook of Pulsar Astronomy (Lorimer & Kramer) (2004) Pulsars, Manchester & Taylor (1977) Pulsar Astronomy, Lyne & Graham-Smith (2006) Physics of the pulsar magnetosphere, Gurevich & Beskin (1993) There have also been excellent summaries and reviews of the current state of pulsar research. These include the following reviews of interest to the general reader: center Reviews of interest to the general public "Fifteen months of pulsar astronomy", (Radhakrishnan 1969) "Pulsars for the Beginner" (1971) "Three years with pulsars", (Hewish 1972) "Wealth of data on pulsars", (Bell Burnell 1977) "Little Green Men, White Dwarfs or Pulsars?" (Bell Burnell 1979) "Historical aspects of gamma-ray astronomy" (Sreekantan 2002) "Presidential Address: Pliers, pulsars and extreme physics" (Bell-Burnell 2004) "The Wonders of Pulsars" (Hewish 2008) "Background to Discovery: Some Recollections" (Hewish 2008) “Reflections on the discovery of pulsars” (Bell Burnell 2009) and the following, more advanced reviews: center More advanced reviews "Problems of Understanding Pulsars", (Smith 1973) Weisberg (1993) provides a guide to the literature on radio pulsars "Was Einstein 100% right?" (Damour 1994) "The Insides and Outsides of Pulsars" (Graham-Smith 1994) "The pulsar planets update" (Wolszczan 1995) "Gamma-ray pulsars: emission zones and viewing geometries" (Romani & Yadigaroglu 1995) "physics of SGRs" (Melia & Fatuzzo 1995) "The next five years of pulsar timing" (Taylor 1996) "Applications of pulsar timing" (Wolszczan 1997) "Radio pulsar searches: present and future" (D'Amico 1998) "Radio pulsar timing" (Bell 1998) "The Status of Pulsar Emission Theory" (Melrose 2000) "What's new in the pulsar world?" (Lorimer 2000) "Gravitational wave experiments and early universe cosmology (2000) "Pulsar Observations I. -- Propagation Effects, Searching Distance Estimates, Scintillations and VLBI (Cordes) and Pulsar Observations II. -- Coherent Dedispersion Polarimetry, and Timing (Stairs) "Testing General Relativity with Pulsar Timing" (Stairs (2003) "Bow shocks around pulsars and neutron stars" (Gaensler 2005) "The strongest cosmic magnets: soft gamma-ray repeaters and anomalous X-ray pulsars" (Mereghetti 2008) "Fifteen years of the neutron star planet research" (Wolszcan 2008) “Pulsar Timing and Tests of General Relativity” (Stairs 2010) “Pulsar Timing Arrays and their Applications” (Manchester 2011) “X-ray pulsars: a review “TeV gamma-ray astronomy: A summary” – Holder (2012) "The surprising Crab pulsar and its nebula: a review" - Buhler & Blandford (2014) "The Double Pulsar J0737-3039A/B: a decade of surprises" - Burgay, Kramer & McLaughlin (2014) "The Confrontation between General Relativity and Experiment" - Will (2014) "1974: the discovery of the first binary pulsar" - Damour (2015) The fundamental concepts of pulsar astronomy have been well covered in these books and reviews. However, the pulsar and neutron star research fields are extremely active and new discoveries are made regularly. One advantage of a wikibook is that updates can be made as needed. The pulsar research fields cover numerous topics and no individual person is an expert in them all. Therefore, the second advantage of a wiki book is that experts on diverse topics can all contribute to the book. Of course, wiki-books have advantages over standard text books. They can include animations, tables can be sorted in different ways and the text can be quickly and easily searched. Contributing to this wikibook This wikibook is open for contributions. Any contributors must ensure that no copyright issues arise from their contributions, in particular by copying text from elsewhere and in using figures or animations from elsewhere. This book has made extensive use of NASA's Astrophysics Data System.