VIRTUAL Thursday, May 12th 2022 3:45 – 4:45 pm (MT) WEBEX Speaker: Diana S. Parno Assistant Professor, Department of Physics, Carnegie Mellon University “The Unbearable Lightness of Neutrinos” Abstract: Ever since it was first hypothesized more than 90 years ago, the strange and ghostly particle called the neutrino has mystified and inspired particle and nuclear physicists. After decades of experimental and theoretical work, we have now firmly established that neutrinos have mass, and yet their absolute mass scale remains unknown. Now, after many years of painstaking design, construction, and commissioning work, the Karlsruhe Tritium Neutrino experiment (KATRIN) has recently improved the world's best direct neutrino-mass sensitivity by more than a factor of two, establishing at 90% confidence that the neutrino mass scale is less than 0.8 eV/c^2. I will give a tour of KATRIN's 70-m beamline, describe our spectral fits and systematic uncertainties, and show a glimpse of KATRIN's future. Bio: Diana Parno earned her PhD in 2011 from Carnegie Mellon University, with a dissertation on the spin structure of the neutron as explored at Jefferson Lab. She soon shifted her attention to a different neutral particle — the neutrino — with a postdoc position at the University of Washington, where she eventually joined the research faculty and became Associate Director of the Center for Experimental Nuclear Physics and Astrophysics (CENPA). In 2017 she returned to CMU, and is now an Assistant Professor of Physics there. She is an Analysis Co-coordinator for the KATRIN and COHERENT experiments and received a DOE Early Career Award in 2021 to support a heavy-water neutrino detector for COHERENT. She was the chair of the writing team for the Best Practices Guide for LGBT+ Inclusion in Physics and Astronomy Departments in 2018, and helped host the Pittsburgh site of the Conference for Undergraduate Women in Physics 1 month before the pandemic.