NANOGrav is a collaboration of scientists working to detect and study gravitational waves — tiny ripples in the fabric of space and time.
The National Science Foundation (NSF) has awarded the North American Nanohertz Observatory for Gravitational Waves (NANOGrav) $14.5 million over 5 years to create and operate a Physics Frontiers Center (PFC).
The NANOGrav PFC will address a transformational challenge in astrophysics: the detection of low-frequency gravitational waves. Gravitational waves are elusive ripples in the fabric of space-time, which theories predict should arise from extremely energetic and large-scale cosmic events, such as orbiting pairs of massive black holes found at the centers of merging galaxies, phase transitions in the very early Universe, or as relics from cosmic inflation, the period just after the Big Bang when all of the Universe that we can see expanded rapidly from a minuscule volume in a tiny fraction of a second.
In Einstein’s theory of gravity, these events produce waves that distort, or ripple, the actual fabric of the cosmos as they emanate throughout space. The waves have such a long wavelength—significantly larger than our Solar System—that we cannot build a detector large enough to observe them. Fortunately, the Universe itself has created its own detection tool, millisecond pulsars—the rapidly spinning, superdense remains of massive stars that have exploded as supernovas. These ultra-stable stars are nature’s most precise celestial clocks, appearing to “tick” every time their beamed emissions sweep past the Earth like a lighthouse beacon. Gravitational waves may be detected in the small but perceptible fluctuations—a few tens of nanoseconds over five or more years—they cause in the measured arrival times at Earth of radio pulses from these millisecond pulsars.
NANOGrav was founded in 2007 and at the time consisted of 17 members in the United States and Canada. It has since grown to 55 scientists and students at 15 institutions. The NANOGrav PFC will provide funding for 23 senior personnel, 6 postdoctoral researchers, 10 graduate students, and 25 undergraduate students distributed across 11 institutions.Read More...
Gravitational wave astronomy is at the cutting edge of modern science and is about to open a whole new window on our Universe.
About this image: An artist's impression of two merging black holes. The blue waves represent gravitational waves, which actually emit no light. NANOGrav will be sensitive to systems like this. Image credit: NASA
We use exotic objects called pulsars to create a "cosmic global positioning system".
About this image: A schematic diagram of a pulsar timing array. NANOGrav uses this technique to detect the influence of gravitational waves on the Earth.
We are a diverse group of astronomers, physicists, and engineers comprised of senior scientists, postdoctoral fellows, and graduate and undergraduate students.
About this image: NANOGrav members gather for a group photo at our Fall 2012 meeting at Oberlin College.
NANOGrav members are located at over a dozen institutions throughout North America, and we collaborate with colleagues from around the world.
About this image: The location of NANOGrav member institutions across the United States and Canada.
We predict that we will detect gravitational waves within the next decade. But detection is only the first step towards ushering in a new era of gravitaional wave astronomy.
About this image: In this graph, solid lines represent the sensitivity of current and future gravitational wave experiments (regions above the lines can be detected). The shaded regions show the expected strength of gravitational waves from various sources according to different models. Pulsar timing arrays are towards the left, at the lowest frequencies, and are expected to make a detection of supermassive black holes or cosmic strings by no later than 2020.
Laura Sampson, Neil Cornish and Sean McWilliams have had their paper entitled Constraining the Solution to the Last Parsec Problem with Pulsar Timing accepted for publication in Physical Review D.
Maura McLaughlin was recently named an Eberly Family Distinguished Professor of Physics and Astronomy" at West Virginia University
Wei Wei Zhu and collaborators have released an exciting new paper entitled "Testing Theories of Gravitation Using 21-Year Timing of Pulsar Binary J1713+0747". Read it on the arXiv here
Jim Cordes and Dan Stinebring (along with Ryan Shannon) have released a paper discussing "Frequency-Dependent Dispersion Measures and Implications for Pulsar Timing". Read it on the arXiv here
Michael Lam and collaborators published Pulsar Timing Errors from Asynchronous Multi-frequency Sampling of Dispersion Measure Variations" in the Astrophysical Journal
Dusty Madison was awarded an NRAO Jansky Fellowship. He will continue his work with NANOGrav from NRAO in Charlottesville, VA upon completion of his PhD at Cornell University. He joins Sarah Burke Spolaor (Jansky Fellowship 2014) as NANOGrav's second current Jansky Fellow.
Chiara Mingarelli has had her thesis accepted for publication in the Springer Theses series. Internationally top-ranked research institutes select their best thesis annually for publication in this series.
This material is based in part on work supported by the National Science Foundation under Grant Number 968296. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.