Astrophysics Seminar

Astrophysics Seminar: "The NIHAO project: simulating galaxy formation in a dark universe"

Location: 
Kaplun building, Room No. 200
Tue, 17/01/2017 - 12:30 to 13:30

Lecturer: Prof. Andrea Macciò Affiliation: NYU Abu Dhabi Abstract: In a Universe dominate by Dark Matter and Dark Energy, galaxy formation is a complex mixture of hierarchical halo assembly, dissipational processes and secular evolution. I will then review the past years efforts of my research group at NYUAD in creating realistic (disk) galaxies in a cosmological context, with particular emphasis on the role of stellar feedback. I will then introduce the NIHAO project, a new, unmatched, suite of high resolution cosmological simulations. I will highlight

Astrophysics Seminar: "Observational Studies of Exoplanets – Transits and More"

Location: 
Kaplun building, Room No. 200
Tue, 10/01/2017 - 12:30 to 13:30

Lecturer: Dr. Aviv Ofir Affiliation: Weizmann Institute of Science Abstract: How can one study objects one cannot even see? This is the challenge that observational exoplanets researchers are facing. In this talk I will start by shortly reviewing the different observational techniques used for studying exoplanets: radial velocity, transits, microlensing, direct imaging and astrometry. I will then focus on transits - the passage of an exoplanet in from of its host star. These are usually thought of as the passage of a circular black disk in front of a luminous

Astrophysics Seminar: "The space road to UHECRs studies in the large exposure era: JEM-EUSO and its pathfinders"

Location: 
Kaplun building, Room No. 200
Tue, 28/06/2016 - 12:30 to 13:30

Lecturer: Dr. Etienne Parizot Affiliation: APC Paris Abstract: Ultra-high-energy cosmic rays (UHECRs) stand as one of the pillars of the rapidly developing multi- messenger strategy for high-energy astrophysics and astroparticle physics. JEM-EUSO is currently the most advanced international project aiming at a significant increase in exposure for the study of UHECRs. As a space- based instrument, it will allow for the first time a full-sky coverage with identical exposure and experimental performances, which appears essential to investigate individual

Astrophysics Seminar: "Efficiency of Planetesimal Ablation in Jovian Envelopes"

Location: 
Kaplun building, Room No. 200
Tue, 03/01/2017 - 12:30 to 13:30

Lecturer: Dr. Arazi Pinhas Affiliation: Institute of Astronomy, University of Cambridge Abstract: Observations of exoplanetary spectra are leading to unprecedented constraints on their atmospheric elemental abundances, particularly O/H, C/H, and C/O ratios. Recent studies suggest that elemental ratios could provide important constraints on formation and migration mechanisms of giant exoplanets. A fundamental assumption in such studies is that the chemical composition of the planetary envelope represents the sum-total of compositions of the accreted gas and

Special High Energy Astrophysics Seminar: Accretion in relativistic binary black hole systems

Location: 
Kaplun building, Room No. 200
Sun, 28/05/2017 - 12:30 to 13:30

Lecturer: Prof. Julian Krolik Affiliation: Johns Hopkins University Additional details of the upcoming Astrophysics' seminars can be found on the following link. ‏האירוע הזה כולל שיחת וידאו ב-Google Hangouts. הצטרף: https://plus.google.com/hangouts/_/mail.huji.ac.il/high-energy?hceid=bWFpbC5odWppLmFjLmlsX2c0czhydDlpcmhwZzRvdGNybWIzZGFqcjdvQGdyb3VwLmNhbGVuZGFyLmdvb2dsZS5jb20.rd31g26l8om1re9sv0n0570h2o&hs=121

Astrophysics Seminar: "Determining the acceleration mechanism of quasar-driven outflows and the thermal properties of circumgalactic gas"

Location: 
Kaplun building, Room No. 200
Tue, 27/12/2016 - 12:30 to 13:30

Lecturer: Dr. Jonathan Stern Affiliation: Galaxies and Cosmology Department Max-Planck-Institute for Astronomy [MPIA] Abstract: I will present two novel observational tests of astrophysical theories that are central to our understanding of galaxy evolution. The first test concerns quasar- driven galactic-scale outflows, which are often invoked by cosmological simulations to regulate star formation in massive galaxies. Several physical mechanisms have been proposed for the acceleration of these outflows, such as the ram pressure of shock-heated

Astrophysics Seminar: "Cosmic Ray Diffusion in a Dynamic Milky Way: Implications to Composition, Positron/electron Ratio and the Gama Ray Sky"

Location: 
Kaplun building, Room No. 200
Tue, 14/06/2016 - 12:30 to 13:30

Lecturer: Mr. David Benyamin Affiliation: Racah Institute of Physics, The Hebrew University of Jerusalem Abstract: Over the years, significant effort has been devoted to the understanding of cosmic ray propagation in the galaxy, based on the energy dependence of the secondary to primary ratios in galactic cosmic rays. We developed a fully three dimensional numerical code describing the diffusion of cosmic rays in the Milky Way. This code enables us to explore a model in which a large fraction of the cosmic ray acceleration takes place in the vicinity of galactic spiral arms and

Astrophysics Seminar: "TBA" (Dr. Elinor Medezinski, Department of Astrophysical Sciences, Princeton University)

Location: 
Kaplun building, Room No. 200
Tue, 21/11/2017 - 12:30 to 13:30

Additional details of the upcoming Astrophysics' seminars can be found on the following link. ‏האירוע הזה כולל שיחת וידאו ב-Google Hangouts. הצטרף: https://plus.google.com/hangouts/_/mail.huji.ac.il/astrophysics?hceid=bWFpbC5odWppLmFjLmlsX2c0czhydDlpcmhwZzRvdGNybWIzZGFqcjdvQGdyb3VwLmNhbGVuZGFyLmdvb2dsZS5jb20.2rj2e02855c6e7jvu7o0v693l9&hs=121

Astrophysics Seminar: "Angular correlation of cosmic neutrinos with astrophysical cosmic-ray and γ-ray sources"

Location: 
Kaplun building, Room No. 200
Tue, 15/11/2016 - 12:30 to 13:30

Lecturer: Dr. Reetanjali Moharana Affiliation: Racah Institute of Physics, The Hebrew University of Jerusalem Abstract: IceCube is the world’s largest detector for cosmic neutrinos, built in South Pole. Recently reported 54 high-energy starting events (HESE) by IceCube is one of the main attractions for astrophysics as well as particle physics. This sample collected within 1347 days of operation, have deposited energy ranging from 20 TeV to 2 PeV. These events correspond to a 6.5σ detection of cosmic neutrinos above an estimated ~9.0 atmospheric neutrino

Astrophysics Seminar: "The tidal disruption of G2"

Location: 
Kaplun building, Room No. 200
Tue, 09/05/2017 - 12:30 to 13:30

Lecturer: Mr. Elad Steinberg Affiliation: Racah Institute of Physics, The Hebrew University of Jerusalem Abstract: Recently a gas cloud, called G2, has been observed in the midst of being tidally disrupted in the center of our galaxy. I'll talk about recent advances in the understanding of the disruption process, obtained with analytic arguments coupled with simulations done with the RICH code. Additional details of the upcoming Astrophysics'

Astrophysics Seminar: "Childhood Obesity Among Black Holes - on The Early Growth of Supermassive Black Holes and Their Host Galaxies"

Location: 
Kaplun building, Room No. 200
Tue, 20/12/2016 - 12:30 to 13:30

Lecturer: Dr. Benny Trakhtenbrot Affiliation: Institute of Astronomy, ETH Zurich Abstract: Supermassive black holes (SMBHs), with masses reaching ten billions solar masses, are found in the centers of most galaxies, and their growth and energy release mechanisms appear to be closely linked to the galaxies that host them, making them central to our understanding of galaxy evolution. However, the existence of these extreme systems less than 1 Gyr after the Big Bang poses major challenges to our understanding of black hole formation and early growth. I will