graduate

Interaction of matter and radiation under extreme astrophysical conditions

TYPEDistinguished Lecture Series
Speaker:Rashid Sunyaev
Affiliation:Max Planck Institute for Astrophysics in Garching, Germany
Dates:17.11 - 21.11.2013
Time:All Day
Location:Physics Department Technion
Abstract:Astrophysics and Cosmology provide us with an exciting variety of physical conditions not achievable in ground based laboratories. Prof. Rashid Sunyaev plans to speak on: (a) how the presence of hot (kTe ~ 3 - 10 KeV) rarefied gas in clusters of galaxies (most massive gravitationally bound objects in the Universe) leads to the appearance of "negative sources" in the angular distribution of the Cosmic Microwave Background Radiation (CMB), and permits the peculiar velocities of these clusters to be measured relative to the unique coordinate frame where the CMB is isotropic. The Planck spacecraft, ground based South Pole telescope, and Atacama Cosmology Telescopes discovered recently hundreds of previously unknown Clusters of Galaxies at high redshifts, by detecting these "negative sources." Prof. Sunyaev will describe: The Russian-German Spectrum-X/eRosita space mission, which plans to detect all clusters of galaxies in the observable universe, and up to 3 million accreting supermassive black holes (Active Galactic Nuclei), during a 4-year X-Ray sky survey. (b) How and at which redshifts the observed close to ideal black body spectrum of the CMB was formed. Why do we dream that proposed space missions, such as PRISM and PIXIE, will be able to detect traces of any significant energy release in our Universe at redshifts smaller than 2 million? (c) How X-Ray observations are able to detect traces of strong activity of the central black hole of our Galaxy that occurred hundreds of years ago. Why we believe that the iron K-alpha line will become a great instrument for the investigations of molecular and atomic hydrogen clouds in our and external galaxies. Prof. Rashid Sunyaev has done fundamental work and is a leader in the fields of Cosmology and High Energy Astrophysics. In particular, with Yakov B. Zel'dovich, he proposed what is known as the Sunyaev-Zel'dovich (SZ) effect, which is due to electrons associated with hot gas in galaxy clusters scattering the CMB radiation. In their work on emission from accreting black holes, Sunyaev and Shakura developed a model of accretion disks, which describes the structure of matter spiraling into a black hole and its X-ray emission. In recognition of his achievements, Prof. Sunyaev has won many prizes including: the Gold Medal of the Royal Astronomical Society (1995), the Bruce Medal ( 2000) for a lifetime of outstanding research in astronomy, Heineman Prize (2003), Crafoord Prize (2008), and Kyoto Prize (2011). He is a member of the Russian Academy of Sciences (since 1984).