[Theory-seminars] Seminars next week

[Carlota Andres]

Dear all, 

Here is a reminder for next week's seminars:

Theory Seminars:

-Monday, December 10th, 1:00PM, Room L102
Jian Liang (U. of Kentucky), "Calculating hadronic tensor on the lattice" 

Abstract:
The direct lattice calculation of hadronic tenor is believed to be helpful for both parton physics in the deep inelastic scattering (DIS) region and neutrino-nucleus scatterings in the shallow inelastic scattering (SIS) region. In this talk, I will briefly introduce the framework of calculating hadronic tenor on the lattice. The inverse problem encountered in the calculation and several methods aiming to solve this problem will be discussed. Preliminary numerical results show that fine lattice spacings are crucial to our calculation.


-Wednesday, December 12th, 1:00PM, Room L102
Aleksandrs Aleksejevs (Memorial University), "The Role of Two-Loop Electroweak Contributions in Search for Physics Beyond the Standard Model"

Abstract:
As the new generation of precision experiments aims to search for physics beyond the Standard Model, it becomes increasingly important to evaluate the relevant higher-order corrections. In collaboration with MOLLER and P2, we work to address the full set of two-loop electroweak radiative corrections to electron-electron (Møller) and electron-proton scattering cross sections and asymmetries. Clearly, the two-loop calculations have to be automatized to keep precision, and that requires a new approach. In this presentation, we will review progress in the evaluation of the electroweak radiative corrections for Møller and describe the recent developments in dispersive subloop insertion approach in two-loop calculations.


-Friday, December 14th, 1:00PM, Room F224-225
Robert Perry (U. of Adelaide), "Hadron Electromagnetic Form Factors"

Abstract: 
Electromagnetic form factors give Lorentz invariant information about the electromagnetic charge distributions inside hadrons. They are thus a key probe of the dynamics of QCD in the low energy, non-perturbative regime. Importantly, it is well known that due to its characteristically light mass, the pion plays an important role in low energy observables. In particular, the effects of implementing pion loop corrections at the hadron level (as opposed to the quark level) will be discussed. I will show results for electromagnetic form factors calculated in the NJL Model, and in particular, that one obtains am improved prediction of the predicted Hyperon Magnetic moment when the pion loop effects are implemented in this way.
One important input into this calculation is the pion form factor itself. Modern extractions of the pion form factor for moderate values of the photon virtuality (above about 0.3 GeV^2) arise from a model dependent extraction from pion electro-production data. In the second half of the talk, a simple model of pion electro-production, will be described and used to examine the model dependence of the extraction method. In the context of this simple model, the extracted form factor is systematically overestimated.


BlueJeans connection: https://bluejeans.com/321085255

Raza, Vincent, Carlota