TEMPO2

TEMPO2
Name	TEMPO2
Programming language	C, Python, FORTRAN
Operating system	Unix-like, macOS, Windows (via Cygwin)
Genre	Pulsar timing software

TEMPO2

TEMPO2 is a precision pulsar-timing package used for modeling, fitting, and analyzing the pulse arrival times from radio, X-ray, and gamma-ray observatories. It provides high-fidelity timing solutions that interface with instruments and observatories such as Parkes Observatory, Arecibo Observatory, Green Bank Telescope, Chandra X-ray Observatory, and Fermi Gamma-ray Space Telescope. TEMPO2 supports workflows linking pulsar catalogs maintained by European Pulsar Network, ATNF Pulsar Catalogue, and databases curated by institutions like CSIRO and NASA.

Overview

TEMPO2 is designed for high-precision analysis of rotational and orbital parameters for rotating neutron stars discovered in surveys by Palomar Observatory, Jodrell Bank Observatory, Arecibo Observatory, Green Bank Telescope, and LOFAR. The package ingests time-of-arrival measurements produced by pipelines from instruments operated by Square Kilometre Array Organisation, MeerKAT, FAST, and observatories associated with European Southern Observatory. It is used in collaborations such as the International Pulsar Timing Array, North American Nanohertz Observatory for Gravitational Waves, and the Parkes Pulsar Timing Array to search for signals predicted by General relativity, Gravitational waves, and models developed at institutions like Max Planck Institute for Radio Astronomy and MIT.

Features and Capabilities

TEMPO2 implements multi-parameter least-squares fitting, model comparison, and residual analysis for datasets from arrays including Very Large Array, Atacama Large Millimeter/submillimeter Array, and telescopes of the National Radio Astronomy Observatory. The software supports plugins and toolchains developed by groups at Monash University, Swinburne University of Technology, University of Manchester, and University of British Columbia. It handles barycentric corrections using ephemerides such as DE421, DE430, and incorporates planetary models from Jet Propulsion Laboratory. TEMPO2 provides extensions for template matching, polarization calibration consistent with pipelines used by European Space Agency missions, and timing model components tied to standards from International Astronomical Union.

Mathematical and Physical Models

TEMPO2 models pulsar spin-down using formalisms drawing on work by P. Goldreich, W. H. Press, and theories tested in contexts like the Hulse–Taylor binary, PSR B1913+16, and PSR J0737−3039A/B. It includes relativistic binary models such as those based on the Damour–Deruelle parametrization and frameworks applied to systems studied at Princeton University and Harvard–Smithsonian Center for Astrophysics. The software accounts for dispersion measure variability influenced by interstellar medium studies from teams at Arecibo Observatory, Jodrell Bank Observatory, and Max Planck Institute for Radio Astronomy, and incorporates propagation effects modeled in research from University of Chicago and Caltech. Timing corrections reference standards established by International Bureau of Weights and Measures and ephemerides used by Jet Propulsion Laboratory.

Software Architecture and Implementation

TEMPO2 is implemented in a modular architecture with a core engine in C and plugin interfaces compatible with Python, enabling interoperability with analysis ecosystems at CERN and Los Alamos National Laboratory. The build system and continuous integration practices mirror workflows from projects like GNU Project and use version control platforms similar to those employed by GitHub and GitLab. Its I/O formats interoperate with data formats standardized by FITS conventions adopted by European Space Agency and tools used at STScI and NRAO. Performance-critical routines draw on numerical libraries and algorithms referenced in publications from Numerical Recipes and high-performance computing centers at Argonne National Laboratory.

Applications and Use Cases

TEMPO2 is central to timing campaigns for millisecond pulsars used in gravitational-wave detection efforts by International Pulsar Timing Array and European Pulsar Timing Array, and for tests of alternative theories of gravity explored by researchers at Perimeter Institute and Institute for Advanced Study. It supports timing solutions for targets from surveys conducted by PALFA Survey, Pulsar Arecibo L-band Feed Array, High Time Resolution Universe Survey, and programs run at CSIRO Astronomy and Space Science. The package is used in characterization of glitches and timing noise studied at Max Planck Institute for Radio Astronomy and for multi-wavelength timing alignment between datasets from Fermi Gamma-ray Space Telescope, XMM-Newton, and Chandra X-ray Observatory.

Development History and Release Timeline

TEMPO2 originated from efforts by research groups established at Swinburne University of Technology, with contributions from collaborators at University of Manchester, Australia Telescope National Facility, and Monash University. Key releases coordinated with workshops at institutions like University of British Columbia and conferences hosted by American Astronomical Society and International Astronomical Union introduced features for gravitational-wave searches and plugin frameworks. The project evolved alongside related efforts such as TEMPO and drew comparisons in community discussions at meetings of European Pulsar Network and working groups of the International Pulsar Timing Array.

User Community and Support

The TEMPO2 user community includes researchers at University of Manchester, Max Planck Institute for Radio Astronomy, CSIRO, Princeton University, MIT, Monash University, Swinburne University of Technology, and observatory teams from Parkes Observatory and Green Bank Telescope. Support is coordinated through mailing lists, workshops at conferences organized by the American Astronomical Society and International Astronomical Union, and collaborative repositories akin to those used by projects at CERN and NASA. Training materials and example pipelines are distributed within curricula at universities such as University of Melbourne and University of Sydney.

Category:Astronomy software