Events at Physics |
Events on Wednesday, February 18th, 2015
- NPAC (Nuclear/Particle/Astro/Cosmo) Forum
- Faculty Candidate Seminar
- Measuring the Neutrino Mass with Tritium Beta Decays
- Time: 8:30 am - 9:30 am
- Place: 4274 Chamberlin Hall
- Speaker: Noah Oblath, MIT
- Abstract: Neutrinos are the most common matter particles in the universe, and yet many fundamental questions about them remain unanswered. They are a crit- ical part of our understanding of everything from cosmology and astrophysics to nuclear reactors and particle accelerators. The absolute neutrino mass scale is one of those unanswered questions, and the most sensitive direct measure- ments of it are made by tritium beta-decay experiments. I will discuss two such experiments: the Karlsruhe Tritium Neutrino Experiment (KATRIN), and Project 8. The KATRIN experiment will use a large electromagnetic spectrometer to improve the sensitivity to the neutrino mass scale by an order of magnitude over the previous generation of tritium beta-decay experiments. The Project 8 experiment will allow us to further improve the sensitivity to the neutrino mass using a novel technique: measuring the frequency of the cyclotron radiation emitted by beta-decay electrons as they travel in a mag- netic field. I will describe these experimental efforts, including recent results from Project 8, and discuss how, over the next several years, they will both contribute to our knowledge of the properties of neutrinos and their role in the universe.
- Host: Dasu
- Department Meeting
- Time: 12:15 pm
- Place: 5310 Chamberlin Hall
- R. G. Herb Condensed Matter Seminar
- Faculty Candidate Seminar
- Spin-charge scattering in Luttinger Liquids
- Time: 4:00 pm
- Place: 4274 Chamberlin Hall
- Speaker: Alex Levchenko
- Abstract: I will discuss the violation of spin-charge separation in generic Luttinger liquids and investigate its effect on the relaxation, thermal and electrical transport of genuine spin-1/2 electron liquids in ballistic quantum wires. We will identify basic scattering processes compatible with the symmetry of the problem and conservation laws that lead to the decay of plasmons into the spin modes and also discuss Brownian backscattering of spin excitations. I will present a closed set of coupled kinetic equations for the spin-charge excitations and solve the problem of electrical and thermal conductance of interacting electrons for an arbitrary relation between the quantum wire length and spin-charge thermalization length.
- Host: Coppersmith