What is LIGO ?
LIGO (the Laser Interferometer Gravitational-Wave Observatory) is a
cutting-edge project to detect gravitational waves directly for the
first time. These waves, predicted by Einstein's general theory of
relativity, are emitted when matter moves in certain ways; in a sense
they are the "echo" of a rapidly-changing gravitational field. Black
holes and neutron stars are expected to emit gravitational waves when
they orbit closely, merge, or are perturbed; collapsing massive stars
and possibly other astrophysical sources should also emit
gravitational waves through a number of physical mechanisms that
have been modeled but not yet confirmed. Upgrades to the three LIGO
detectors in the U.S. and its sister detectors Virgo and GEO600 in
Europe, currently in progress, will reach sensitivity levels at
which gravitational-wave signals are expected to be detected regularly.
Measurements of the waves themselves will also determine their
properties (polarization components, etc.) and thereby test the
theory of general relativity.
LIGO thus sits at the interface between physics and astronomy, and
between experiment and theory.
University of Maryland physicists, including
professors Peter
Shawhan (in
the Gravitation Experiment
group)
and Alessandra
Buonanno (in
the Gravitation Theory
group) plus postdocs and students, are active members of the LIGO
Scientific Collaboration, especially in the areas of analyzing the
data to search for and interpret "burst" and "inspiral" signals.
For more information, see...
A few selected papers
- "LOOC UP: locating and observing optical counterparts to gravitational wave bursts", J. Kanner, T. L. Huard, S. Márka, D. C. Murphy, J. Piscionere, M. Reed, and P. Shawhan, Classical and Quantum Gravity 25, 184034 (2008)
- "Implications for the Origin of GRB 070201 from LIGO Observations", B. Abbott et al. (LIGO Scientific Collaboration) plus K. C. Hurley, Astrophysical Journal 681, 1419 (2008).
- "All-sky Search for Gravitational-Wave Bursts in the First Joint LIGO-GEO-Virgo Run", J. Abadie et al. (LIGO Scientific Collaboration and Virgo Collaboration), Physical Review D 81, 102001 (2010).
- "Search for gravitational waves from binary black hole inspiral, merger, and ringdown", J. Abadie et al. (LIGO Scientific Collaboration and Virgo Collaboration), Physical Review D 83, 122005 (2011).