Events
Astrophysics and Cosmology Seminar
Transient sources in galaxy cluster fields: Prospects for different gravitationally lensed transients
Ms. Miriam Golubchik
BGU
Wed, 15 Jan 2025, 11:10
Sacta-Rashi Building for Physics (54), room 207
Abstract: Strong gravitational lensing of transient sources has spurred much interest in recent years. It can teach us about the lensed sources themselves, the composition of the lens (and mainly its dark component), and the expansion rate of the universe through time delays. In this talk I will present results from three papers related to this topic. The first paper concentrates on a strong-lensing mass model for the first JWST galaxy cluster, SMACS J0723.3-7327, that we constructed to enable studies of lensed galaxies and of the lens. The second paper concentrates on an extensive search for transients in a sample of over 40 galaxy clusters, with a main motivation to look for caustic crossing events (CCEs) of distant stars. The search also led to the detection of 6 supernovae candidates, three of them being new discoveries presented and classified in this work for the first time. The third paper discusses yet another type of varying sources that might be lensed by galaxy clusters -- Type I active galactic nuclei (AGN) and quasars. In this work it is suggested that gravitational time delays between multiple images of strongly lensed quasars may be leveraged to conduct Reverberation Mapping at high redshift on a feasible time scale. I will overview our detailed estimates of the number of both high-mass and high-redshift quasars -- including the recently discovered Little Red Dot population -- that are expected to be strongly lensed by clusters and discoverable with different observing facilities.
Quantum optics seminar
Roto-translational levitated optomechanics
Dr. Marko Toros
University of Ljubljana
Wed, 15 Jan 2025, 16:00
Zoom Only
Abstract: Zoom link: https://us02web.zoom.us/j/84709027087?pwd=rAt6bE9eHxkT25U9jItNPrCe4v2xTT.1
Abstract:
We will start by giving a pedagogical introduction to the description of 3D objects such as nanoparticles. We will introduce the basic concepts required to write the dynamics for the roto-translational degrees of freedom in a Hamiltonian form. We will then proceed to show how to obtain a complete description of all the optomechanical forces and torques for anisotropic particles in a classical setting. In particular, starting from the classical optomechanical interaction, we will recover the gradient and radiation pressure forces and torques as well as the recoil heating of translations and rotations. We will conclude by briefly highlighting how such effects change as we change the particle shape and size in experiments.
Particles and Fields Seminar
TBA
Vladimir Narovlansky
IAS
Mon, 20 Jan 2025, 14:00
Sacta-Rashi Building for Physics (54), room 207
Abstract:
Physics Colloquium
Understanding Star Formation: From Local Galaxies to the Very Young Universe
Prof. Adi Nusser
Technion
Tue, 21 Jan 2025, 12:00
Ilse Katz Institute for Nanoscale Science & Technology (51), room 015
Abstract: Stars form in galaxies when dense regions of gas collapse under gravity, igniting nuclear fusion in their cores. We present a model for understanding the relationship between gas density and the rate at which stars form in a galaxy. This observational relation is known as the Kennicutt-Schmidt (KS) and describes how regions with higher gas density tend to have higher rates of star formation, providing a key framework for studying galactic evolution. The James Webb Space Telescope (JWST) has revealed galaxies with unexpectedly high rates of star formation at very early times, less than a billion years after the Big Bang. . By examining the cosmic histories of these galaxies, we demonstrate how the KS law provides a framework for explaining these elevated star formation rates.
Biological and soft-matter physics
TBA
Prof. Ayelet Lesman
School of Mechanical Engineering, Tel-Aviv University
Thu, 23 Jan 2025, 12:00
Sacta-Rashi Building for Physics (54), room 207
Abstract: TBA
Particles and Fields Seminar
TBA
Bar Glik
BGU
Mon, 27 Jan 2025, 14:00
Sacta-Rashi Building for Physics (54), room 207
Abstract:
All events
Google calendar
