This Thursday (April 27, 2017) Nobel Laureate, Art McDonald, of Queens University in Kingston Ontario, will be at Virginia Tech to give the next lecture in the J. Mark Sowers Distinguished Lecture Series. The lecture, titled "How unusual: Going 1.2 Miles Underground to Study the Sun and the Space Between the Stars," will be held at 7:30 pm in McBryde Hall, room 100. It is open to all and free of charge, but please do plan to arrive early as the available seating should fill-up quickly.
Prof. McDonald is best known for his role as leader of the Sudbury Neutrino Observatory (SNO)
Collaboration, which made critical contributions to our understanding of neutrinos, by observing
neutrinos from the sun and using them to show that neutrinos mix between types in a process known as
oscillations, which also proved that neutrinos have mass. For this contribution, Prof. McDonald was
awarded the 2007 Benjamin Franklin Medal in Physics, and he shared the 2015 Nobel Prize in Physics and \
the 2016 Breakthrough Prize in Fundamental Physics.
|Art McDonald accepting the 2015 Nobel Prize for Physics.|
After almost 3 years of preparations, an experiment lead by CNP Members Camillo
Mariani and Omar Benhar and aimed at the determination of the nuclear structure of argon started its run
at the Thomas Jefferson National Laboratory (JLab). By detecting protons knocked out from the argon
nucleus by an electron beam, the measurement will provide complete information on the shell structure of
argon, filling an important gap in our knowledge. The collected data will help the neutrino community to
make more reliable estimates of neutrino-argon cross sections and to model nuclear effects more accurately
in the next generation of neutrino-oscillation experiments, such as the Deep Underground Neutrino
Experiment (DUNE). An improved description of nuclear effects will allow a reduction in the systematic
uncertainties in the measurement of charge-parity symmetry violation in neutrino oscillations and the
search for proton decay, bringing us closer to understanding the matter-antimatter asymmetry of the
Universe and constraining possible extensions of the Standard Model of particle physics.
|The Hall A spectrometer at JLab, which will be used in the Argon Scattering Experiment.|
The Center for Neutrino Physics at Virginia Tech will host the 2017 String Phenomenology conference will be held at Virginia Tech, July 3rd through 7th. String Pheno is a forum that brings together diverse researchers aiming to bridge the gap between fundamental theory and observable physics. In light of new data from the LHC, as well as important results from astrophysics and cosmology, such as those coming from LIGO and the Dark Energy Survey, this conference will fully explore the connections between the properties of string theory and the forthcoming new data. The conference includes both invited plenary talks and contributed parallel sessions, and is expected to have a diverse international participation: of the 33 confirmed invited speakers 9 different countries are represented.
|String Pheno Coming to Virginia Tech in July|
In a new study, the Daya Bay Collaboration, which includes several members of the Center for Neutrino Physics, measured the relative contributions of the two main fissionable isotopes, uranium-235 (235U) and plutonium-239 (239Pu), to the antineutrino flux from nuclear reactors. After refueling, a typical power reactor runs mostly on 235U, but over time other fissionable isotopes, like 239Pu build up in the reactor fuel. Daya Bay used this increasing rate of 239Pu fission to determine, for the first time, the interaction rates of neutrinos from the two isotopes in their detectors. The results of this study turned out to have interesting and unexpected consequences for a vexing problem known as the Reactor Antineutrino Anomaly.
The Reactor Antineutrino Anomaly refers to observation, first made in 2011, that the rate of antineutrinos observed in reactor neutrino experiments falls short of theoretical expectations by about 6%. This observation led to speculation that the missing neutrinos may be due to a new type neutrino oscillations involving the hypothetical sterile neutrino. This new result from Daya Bay, which finds that the missing antineutrinos are almost all associated with the 235U flux and are not spread evenly across both isotopes, throws cold water on that speculation, and instead suggests that the anomaly is due to errors in the modeling of the 235U antineutrinos.
|The four identical antineutrinno detector in the Daya Bay far hall.|
The proceedings from Heavy Quarks and Leptons 2016 are now available online.