Calendar

March 2018
Public Access |

- User:
- High-Energy Seminars
- Time:
- 1:30pm - 2:30pm
- Send Reminder:
- Yes - 1 day 4 hour 0 minutes before start
- Description:
Joint Theory Seminar Speaker: Email: Title: Host: Room: 432 Abstract:

- User:
- High-Energy Seminars
- Time:
- 4:10pm - 5:10pm
- Send Reminder:
- Yes - 1 day 4 hour 0 minutes before start
- Description:
High Energy Seminar Speaker: Email: Title: Host: Room: 285 Abstract:

- Description:
- Daylight Savings Time begins

- User:
- High-Energy Seminars
- Time:
- 6:30am - 7:30am
- Send Reminder:
- Yes - 1 day 4 hour 0 minutes before start
- Description:
- Joint Theory Seminar

Speaker:Yusuke Yamada (Stanford)

Email: yusukeyy@stanford.edu

Title: Multi-field alpha attractors

Host: Verhaaren

Room: 432

Abstract:The alpha-attractors are a class of inflationary models, that match the current data with the spectral index of the scalar perturbation. The moduli space of the inflaton field is the hyperbolic geometry and the curvature of the moduli space determines the value of the tensor-to-scalar ratio. Some class of 4D N=1 supersymmetric reduction of superstring theory, M-theory, or maximal supergravity are known to have multiple fields with the hyperbolic moduli space geometry.

In this seminar, I will describe alpha-attractors with multiple moduli fields and show its applications. In particular, we will focus on the merger of moduli fields, which can enhance the value of the tensor-to-scalar ratio effectively. Also, the supersymmetric version of the alpha-attractors has the superpartner scalar of the inflaton. I will show that the superpartner axion field is a good candidate for cold dark matter.

- User:
- High-Energy Seminars
- Time:
- 9:10am - 10:10am
- Send Reminder:
- Yes - 1 day 4 hour 0 minutes before start
- Description:
- High Energy Seminar

Speaker: Michael E. Peskin

Email: mpeskin@slac.stanford.edu

Title: Extracting High-Precision Higgs Boson Couplings at the 250 GeV ILC

Host: mulhearn

Room: 285

Abstract: The International Linear Collider at 250 GeV is expected to produce a sample of half a million Higgs bosons, tagged by recoil Z bosons, through the process e+e- -> Zh. Using this sample, it will be straightforward to measure Higgs branching ratios with high precision. However, we would like to do more -- determine the absolute strengths of Higgs boson couplings, measure the Higgs boson width, and test models of new physics beyond the Standard Model. This second step requires a theoretical framework, which, hopefully, should be as model-independent as possible. In this lecture, I will describe the analysis of this problem using Standard Model Effective Field Theory (EFT), the framework now used to discuss Higgs boson coupling strengths and other tests of the Standard Model at the LHC. It turns out that there is a beautiful synergy between the EFT formalism and the suite of observables available at the ILC that increases the power of both. I will present projections for Higgs coupling uncertainties at the ILC at 250 and 500 GeV and discuss the implications of these for the discovery of new physics through precision Higgs measurements.

- Description:
- St Patrick's Day

- User:
- High-Energy Seminars
- Time:
- 6:30am - 7:30am
- Send Reminder:
- Yes - 1 day 4 hour 0 minutes before start
- Description:
- Joint Theory Seminar

Speaker: Peter Stoffer (UCSD)

Email: pstoffer@ucsd.edu

Title: EFT below the electroweak scale and constraints from electric dipole moments

Host: Xiaochuan Lu

Room: 432

Abstract: Under the assumption that physics beyond the standard model consists of heavy particles well above the electroweak scale, its effects at lower energies can be described by an effective field theory, either SMEFT or HEFT above the electroweak scale. Below the electroweak scale, either theory should be mapped to a low-energy EFT (LEFT), where the heavy standard-model particles are integrated out. This is essentially the well-known Fermi theory of weak interactions. I will present the complete LEFT operator basis up to dimension six (which, surprisingly, so far was missing in the literature) as well as the calculation of the full one-loop RGEs.

At low energies, strong constraints on some LEFT Wilson coefficients come from electric dipole moments. In order to exploit the full power of neutron EDM measurements, the uncertainties of hadronic matrix elements should be reduced, e.g. with lattice calculations. In the second part of the talk, I will present ongoing work on matching calculations between the LEFT framework and a scheme that can be implemented on the lattice.

- User:
- High-Energy Seminars
- Time:
- 9:10am - 10:10am
- Send Reminder:
- Yes - 1 day 4 hour 0 minutes before start
- Description:
- High Energy Seminar

Speaker: Bob Svoboda

Email: rsvoboda@physics.ucdavis.edu

Title: The Accelerator Neutrino Neutron Interaction Experiment (ANNIE)

Host: Bob Svoboda

Room: 285

Abstract: Nature has conspired to make efficient neutrino production from proton beams peak at about 80 GeV, resulting in 1-2 GeV neutrinos that need to travel roughly 1,500 for maximum sensitivity to CP violation and neutrino mass ordering. This is the energy range in which cross-sections are uncertain and models are are ambiguous. The ANNIE experiment seeks to make the first-ever measurement of neutron production from muon neutrino interactions in this energy region. The design and construction of the detector is presented, along with the background results from the just-completed Phase 1. Plans for Phase 2 are presented, which include the first use of Large Area Picosecond Photo Detectors (LAPPDs).

- User:
- High-Energy Seminars
- Time:
- 1:30pm - 2:30pm
- Send Reminder:
- Yes - 1 day 4 hour 0 minutes before start
- Description:
Joint Theory Seminar Speaker: Email: Title: Host: Room: 432 Abstract:

- User:
- High-Energy Seminars
- Time:
- 4:10pm - 5:10pm
- Send Reminder:
- Yes - 1 day 4 hour 0 minutes before start
- Description:
High Energy Seminar Speaker: Email: Title: Host: Room: 285 Abstract: