Speaker Institution : George Washington University
Title : Hunting for Transients in the Radio Sky
Abstract : While a large fraction of the observable Universe is steady and does not change on human timescales, there are objects displaying variability on timescales of years to days, to even small fractions of a second. These cosmic transients are usually associated with the most extreme phenomena in the Universe like neutron stars, black holes, or the formation of these exotic objects. Their variability can be observed across the entire electromagnetic spectrum. Within the multi-wavelength picture, the radio regime reveals incoherent synchrotron emission of high-energy particles moving in the present magnetic fields or coherent radiation from ultra-compact structures. In the past, studies of transients at radio frequencies have mostly been prompted by detections at higher frequencies, in particular because most radio observatories were limited in their field of view and/or sensitivity. This has changed significantly in the last few years: all major radio observatories in ! ! the world have recently been upgraded or are currently being upgraded, and several new facilities have been or are being built. This means large improvements in sensitivity, bandwidth, and spatial, spectral and temporal resolution. Some new observatories explore the low-frequency radio sky down to tens of MHz with unprecedented sensitivity. Furthermore, several new radio facilities have a wide field of view, perfectly suited for efficient surveys of the entire sky and searches for transient radio phenomena. In this talk I will discuss the progress that has been made in our understanding of a variety of transients due to radio observations, discoveries of new phenomena in the radio regime, and the current efforts and future opportunities in the hunt for radio transients. Title of Event: JSI Colloquium Series