binary pulsar PSR B1913+16

binary pulsar PSR B1913+16
Name	PSR B1913+16
Other names	PSR 1913+16, Hulse–Taylor pulsar
Discovery	1974
Discoverers	Russell Hulse, Joseph Taylor
Constellation	Aquila
Right ascension	19h 15m
Declination	+16° (J2000)
Period	59 ms
Companion	neutron star
Distance	~21,000 ly

binary pulsar PSR B1913+16 is a compact binary system discovered in 1974 that consists of a radio pulsar in orbit with another neutron star, notable for providing the first indirect evidence for gravitational radiation through its orbital decay. The system, often associated with Nobel recognition, has been central to tests of relativistic gravity, pulsar timing methodologies, and studies of compact-object evolution. Observations span radio astronomy observatories, national agencies, and international collaborations that intersect with work on gravitational-wave detectors and theoretical physics.

Discovery and Observational History

The system was discovered by Russell Alan Hulse and Joseph Hooton Taylor Jr. using the Arecibo Observatory radio telescope during a survey for pulsars, an effort connected to programs at the National Radio Astronomy Observatory and collaborations with institutions such as Princeton University and University of Massachusetts Amherst. Early follow-up involved teams from the Harvard–Smithsonian Center for Astrophysics, the National Aeronautics and Space Administration, and personnel affiliated with the United States Naval Observatory and the Max Planck Institute for Radio Astronomy. Subsequent monitoring employed facilities including the Green Bank Observatory, the Jodrell Bank Observatory, the Parkes Observatory, and the Very Large Array, coordinated with theoretical input from researchers at Caltech, MIT, University of Cambridge, and University of Chicago. The discovery led to the Nobel Prize in Physics awarded to Hulse and Taylor, and stimulated comparisons with earlier compact-object work by groups at the Institute for Advanced Study and the Los Alamos National Laboratory.

System Characteristics

The binary comprises a 59 millisecond radio pulsar and a compact companion inferred to be a neutron star; mass estimates arise from timing analyses influenced by models developed at Cornell University, Columbia University, and the University of California, Berkeley. Orbital parameters—eccentricity, semi-major axis, inclination, and periastron advance—were measured using techniques refined in collaboration with researchers from Caltech, Stanford University, and Ohio State University. The system’s orbital period of about 7.75 hours and substantial eccentricity place it in the same class studied by groups at the European Southern Observatory and the Kavli Institute for Theoretical Physics. Distance estimates tie into astrometric efforts by teams at the Space Telescope Science Institute and reference frames maintained by the International Astronomical Union and the Jet Propulsion Laboratory.

Relativistic Effects and Orbital Decay

Observed changes in orbital period match predictions of energy loss via gravitational radiation as formulated in Albert Einstein’s General Relativity and elaborated by work from Kip Thorne, Clifford Will, and others at the Institute for Advanced Study and Princeton University. Measured periastron advance, gravitational redshift/time dilation, and Shapiro delay were quantified with input from the Royal Astronomical Society community and theoreticians at Cambridge University. Results paralleled developments in gravitational-wave theory pursued at Massachusetts Institute of Technology and Caltech, and complemented direct-detection campaigns by collaborations forming the LIGO Scientific Collaboration and the Virgo Collaboration. Analytical frameworks drew on post-Newtonian methods advanced by groups at Max Planck Society and the Kavli Institute.

Tests of General Relativity

The system provided the first high-precision test of gravitational-wave emission predicted by General Relativity, influencing evaluation criteria used by panels at the American Physical Society and committees at the Royal Swedish Academy of Sciences. Comparisons with alternative theories—such as scalar-tensor proposals examined by researchers at Paris Observatory and University of Bologna—were performed by teams at MPI for Gravitational Physics and universities including Yale University and University of Toronto. Tight constraints from timing residuals informed parameter estimation approaches used in analyses at Harvard University, Duke University, and University of Amsterdam, contributing to the broader experimental program that includes the Event Horizon Telescope and space-based mission concepts championed by the European Space Agency and NASA.

Pulsar Timing and Measurement Techniques

Precision timing exploited instrumentation and signal-processing advances developed at Arecibo Observatory, Green Bank Observatory, and Jodrell Bank Observatory, integrating backend hardware from institutions like Northrop Grumman and signal-analysis software inspired by work at Bell Labs and AT&T Laboratories. Calibration and clock standards referenced standards maintained by the National Institute of Standards and Technology and the Bureau International des Poids et Mesures, while ephemerides used models from the Jet Propulsion Laboratory and the International Celestial Reference Frame overseen by the International Astronomical Union. Data pipelines incorporated statistical methods and Monte Carlo techniques advanced at Stanford University, University of Oxford, and ETH Zurich, with long-term campaigns coordinated through consortia including the International Pulsar Timing Array and national observatory networks.

Astrophysical Significance and Evolution

The system informed models of binary stellar evolution developed at research centers such as Monash University, University of Tokyo, and University of Cambridge, and shaped predictions for compact-object merger rates relevant to the LIGO Scientific Collaboration and Virgo Collaboration. Its implications affected understanding of supernova mechanisms studied at Los Alamos National Laboratory and Lawrence Livermore National Laboratory, and population synthesis models refined by groups at Stockholm University, University of Barcelona, and Max Planck Institute for Astrophysics. The Hulse–Taylor system remains a benchmark for the end states of massive stars in clusters like Messier 13 and galactic environments surveyed by the Sloan Digital Sky Survey, influencing ongoing observational strategies at facilities including MeerKAT and the future Square Kilometre Array.

Category:Pulsars