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Talk #6 Fast Radio Burst FAST RADIO BURST Nandini Chatterjee Credit: M. Weiss CfA WHAT ARE FAST RADIO BURSTS? • Powerful flashes of light known as fast radio burst (FRBs) • Radio emissions / radio brightness • Lasts about a second, disappears, and never repeats • Only one of the sources have been localized so far • First described in 2007 • FRB are named ‘FRB YYMMDD’ • Example: FRB 010724 • Found more than 2 dozen Credit: Jingchuan Yu, Beijing Planetarium WHAT CAUSES FAST RADIO BURSTS? • Hypothesis 1: Explosions driven by young, fast- spinning neuron stars with strong magnetic fields • Hypothesis 2: Explosion of a star • Hypothesis 3: Black holes combining together can create radio flashes • Hypothesis 4: Generated by intelligent aliens • Hypothesis 5: Blitzar Credit: Space.com BREAKTHROUGH LISTEN • Announced in July 2015 • Goal: Looking for signs of intelligent alien life • Scans the nearest million stars in the Milky Way and star in 100 other galaxies • Cost: $100 million project • Parkes Telescope in Australia is also involved Credit: National Radio Astronomy Credit: Commonwealth Scientific and Observatory Industrial Research Organization Credit: Breakthrough FRB 121102 Listen/UC Berkeley • A dwarf galaxy discovered Nov. 2, 2012 • 3 billion light years away from Earth • Green Bank Telescope detected 15 new pulses high of frequency (August 26) • Brightest emission at around 7 GHz • Source is newly active • Measurement of the properties of these bursts Credit: ASTRON, the Netherlands Institute for Radio Astronomy WHICH HYPOTHESES HAVE BEEN RULED OUT? • The supermassive black hole hypothesis • The intelligent aliens hypothesis • The Blitzar hypothesis Credit: M. Weiss/CfA EARLIER OCCURRENCES 1 2 3 4 August 24, Smallest Largest FRB detected 2001: 5- wavelength wavelength 6 billion light millisecond dispersion dispersion years away burst burst burst WHY IS FRB IMPORTANT? • Sort out source which are unknown • Increase the number that we discover • Approximately 25,000 flashes each day • Hope to discover at least 10 flashes per day • Learn about the universe’s evolution • Better understanding of the “reionization” • Universe Mapping • Study the magnetic fields • Study turbulence & the materials between Earth and the sources Credit: NASA/WMAP Science Team CITATIONS • Billings, Lee. “A Brilliant Flash, Then Nothing: New.” Scientific American, 9 July 2013, www.scientificamerican.com/article/a-brilliant-flash-then- nothing-new-fast-radio-bursts-mystify-astronomers/. • Drake, Nadia. “Storm of Strange Radio Bursts Emerges From Deep Space.” National Geographic, National Geographic Society, 1 Sept. 2017, news.nationalgeographic.com/2017/09/radio-bursts-galaxy-space-breakthrough-listen-science/. • “Fast Radio Bursts May Be Firing Off Every Second.” Www.cfa.harvard.edu/, Harvard-Smithsonian Center for Astrophysics (CfA), 21 Sept. 2017, www.cfa.harvard.edu/news/2017-28. • “Green Bank Telescope Joins ‘Breakthrough Listen.’” National Radio Astronomy Observatory, National Radio Astronomy Observatory, 20 July 2015, public.nrao.edu/news/gbt-breakthrough-listen/. • Kohler, Susanna. “A New Clue in the Mystery of Fast Radio Bursts.” AAS Nova, 28 June 2017, aasnova.org/2017/06/28/a-new-clue-in-the-mystery- of-fast-radio-bursts/. • Sanders, Robert. “Distant Galaxy Sends out 15 High-Energy Radio Bursts.” Berkeley News, 1 Sept. 2017, news.berkeley.edu/2017/08/30/distant- galaxy-sends-out-15-high-energy-radio-bursts/. • Spaleta, Steve. “Mysterious 'Fast Radio Burst' Source Detected.” Space.com, Space.com, 2 Dec. 2016, www.space.com/31250-mysterious-fast- radio-burst-source-detected-video.html. • Wall, Mike. “Could Mysterious Cosmic Light Flashes Be Powering Alien Spacecraft?”Space.com, Space.com, 9 Mar. 2017, www.space.com/35996-fast-radio-bursts-powering-alien-spacecraft.html. • Wall, Mike. “$100 Million E.T. Hunt Spots 15 Mysterious Light Flashes.” Space.com, Space.com, 30 Aug. 2017, www.space.com/37992-fast-radio- bursts-breakthrough-listen.html. • Wall, Mike. “Fast Radio Bursts Flash throughout the Cosmos.” Scientific American, Scientific American, 26 Sept. 2017, www.scientificamerican.com/article/fast-radio-bursts-flash-throughout-the-cosmos/. • “Welcome to the CSIRO Parkes Observatory.” CSIRO Parkes Observatory | Australia Telescope National Facility, Commonwealth Scientific and Industrial Research Organization, www.parkes.atnf.csiro.au/..
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