High-energy physics

South Pole Telescope helps Argonne scientists study earliest ages of the universeOctober 28, 2013

For Argonne physicist Clarence Chang, looking backward in time to the earliest ages of the universe is all in a day’s work.

Insights from Electron Scattering as Input to Precision Neutrino Studies
The 6 GeV program at Jefferson Lab has provided several new insights into the structure of nucleons and nuclei. Some of these results impact the current generation of high-luminosity neutrino scattering experiments aimed at understanding neutrino properties, nucleon structure, and nuclear medium effects. I will briefly highlight some of the results of the Jefferson Lab 6 GeV program which will act as input to current and future neutrino scattering measurements, and discuss the insight into hadronic structure that will be provided by these neutrino measurements.

Truth and Beauty Together: Evidence for S-channel Single Top Production
Single top quarks at the Tevatron are produced via the electroweak interaction from the decay of an off-shell W boson in the s-channel, or fusion of a virtual W boson with a b quark in the t-channel. In particular, the s-channel production rate is comparatively low at the LHC, and the much larger background contamination at the LHC would make it very difficult to measure the s-channel cross section.
Bottom-Up Naturalness
We study the naturalness problem using a model independent bottom up approach by considering models where only the interaction terms needed to cancel the Higgs quadratic divergences are present. If quadratic divergences are canceled by terms linear in the Higgs field, then the collider phenomenology is well covered by current electroweakino and fourth generation searches. If quadratic divergences are canceled by terms bilinear in the Higgs field, then the signatures are highly dependent on the quantum numbers of the new particles.
Argonne research helps pave way for physics Nobel October 8, 2013

The 2013 Nobel Prize in Physics was awarded today to theoretical physicists François Englert and Peter Higgs for their theory of an elementary particle now known as the Higgs boson, which scientists believe is responsible for giving mass to other elementary particles.

The Need for an Early Anti-neutrino Run of NOvA
NOvA, with equal three year neutrino and anti-neutrino runs, can determine the mass hierarchy for only favorable half-plane of \delta_CP , due to hierarchy-\delta_CP degeneracy. In this talk, I consider the residual degeneracies in the first three years of neutrino data of NOvA. Such data is still affected by the sin2^2\theta_13-hierarchy degeneracy if the error in sin2^2\theta_13 is the present 10%, but becomes independent of it, if the error is reduced to 5%.
Project Poltergeist, a Ghostly Neutrino and a Specter
It is not quite Halloween yet... In this talk we will discuss how Project Poltergeist shaped neutrino physics for decades to come and made nuclear reactors the workhorse of early oscillation searches. A renaissance of reactor neutrino experiments around 2010 lead to the very precise measurement of one of the mixing parameters, theta13 -- in the run-up to this measurement flux calculations from the 1980's were scrutinized and surprisingly the flux was found to be higher than previously expected leading to the so-called reactor anomaly.