none

NRAO/Socorro Colloquium Series

Ashley Zauderer

Harvard University

Radio Observations of the Tidal Disruption Event Swift J164449.3+573451: Two Years in Review

On 25 March 2011, an unusual gamma-ray detected transient source (Swift J164449.3+573451) was found. The long-lived X-ray emission and its decline rate, the coincidence of this source with the nucleus of an inactive galaxy, and the energetics indicate this to be a strong candidate for transient accretion onto a supermassive black hole from the tidal disruption of a solar mass star. I will show how radio detections established the presence of a relativistic outflow, not predicted to occur in tidal disruption events. I will summarize the extensive monitoring campaign at radio wavelengths, whereby we track the parsec-scale environment around a previously dormant supermassive black hole. Additionally, the radio observations inform the energetics of the event, the Lorentz factor, and the size. Finally, I will discuss the most recent dramatic change in X-ray emission and compare it to our radio observations. I will summarize the theoretical models presented to-date to explain the observations, and give a brief overview of predicted future behavior and our observing strategy. I will conclude with some comments about other tidal disruption event candidates and constraints on event rates.



March 22, 2013
11:00 am

Array Operations Center Auditorium

All NRAO employees are invited to attend via video, available in Charlottesville Room 230, Green Bank Room 137 and Tucson N525.

Local Host: Michael Rupen

Connect with NRAO

The NSF National Radio Astronomy Observatory and NSF Green Bank Observatory are facilities of the U.S. National Science Foundation operated under cooperative agreement by Associated Universities, Inc.

Founded in 1956, the NSF NRAO provides state-of-the-art radio telescope facilities for use by the international scientific community. NSF NRAO telescopes are open to all astronomers regardless of institutional or national affiliation. Observing time on NSF NRAO telescopes is available on a competitive basis to qualified scientists after evaluation of research proposals on the basis of scientific merit, the capability of the instruments to do the work, and the availability of the telescope during the requested time. NSF NRAO also provides both formal and informal programs in education and public outreach for teachers, students, the general public, and the media.

The U.S. National Science Foundation (U.S. NSF) is an independent federal agency created by Congress in 1950 "to promote the progress of science; to advance the national health, prosperity, and welfare; to secure the national defense..."

AUI collaborates with the scientific community and research sponsors to plan, build, and operate cutting-edge facilities. We cultivate excellence, deliver value, enhance education, and engage the public.