# Particle Physics

This series consists of talks in the areas of Particle Physics, High Energy Physics & Quantum Field Theory.

## Seminar Series Events/Videos

Currently there are no upcoming talks in this series.

## Using quantum computing techniques to detect dark matter axions

Tuesday May 30, 2017
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Quantum non-demolition measurements performed using qubit-based artificial atoms may enable the next generation of higher mass dark matter axion search experiments.  These QND measurements can precisely determine the amplitude of the photon wave sourced by the dark matter axions while placing the back reaction noise into the phase quadrature.

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## The new ultracold neutron facility at TRIUMF

Tuesday May 23, 2017
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A permanent non-zero electric dipole moment of the free neutron (nEDM) violates CP-symmetry. The search for an nEDM contributes to understanding the Baryon asymmetry,
as well as it has a high discovery potential for Beyond Standard Model physics. The tool of choice to investigate the nEDM are ultracold neutrons (UCN), since they have such low energies that they can be stored in traps and allow observation times of hundreds of seconds.

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## Conformal Truncation: QFT Dynamics from CFT Data

Monday May 15, 2017
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Any quantum field theory can be thought of as arising from a perturbed UV conformal field theory, suggesting that information about the full RG flow is encoded in the original CFT. I will discuss ongoing work developing new methods for extracting this information to study strongly-coupled IR dynamics. This method uses a UV basis of conformal Casimir eigenstates to construct the Hamiltonian, which is then truncated at some maximum Casimir eigenvalue and diagonalized to approximate the low energy spectrum of the IR theory.

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## Baryogenesis from L-violating Higgs doublet decay

Tuesday May 09, 2017
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In the framework of the ordinary seesaw model with right-handed neutrinos (and nothing else) we show that the total lepton number violating decay of the Higgs doublet into a right-handed neutrino and a standard model lepton can successfully account for the baryon asymmetry of the Universe. This is possible thanks to thermal effects shortly before the sphalerons decouple.

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## Quark Reggeization from Effective Field Theory

Tuesday May 02, 2017
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We derive in the framework of soft collinear effective field theory (SCET) a Lagrangian describing the t-channel exchange of Glauber quarks, which are incorporated through fermionic potential operators in the effective theory. The Wilson line structure of the operators, which is derived from matching calculations and the symmetries of the effective theory, describe additional soft and collinear emissions from a fermionic t-channel exchange in the forward scattering limit to all orders.

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## Discovering New Physics in Scattering Angles at the LHC

Tuesday Apr 18, 2017
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Since the Higgs, the LHC has offered no discoveries despite a sweeping hunt for new resonances.

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## New Directions in Dark Matter Direct Detection

Tuesday Apr 04, 2017
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Sub-GeV dark matter is a theoretically motivated but largely unexplored paradigm of dark matter. In this talk, I will discuss recent work on the direct detection of sub-GeV dark matter through dark matter-electron scattering. I will present some motivated models that can be probed with these techniques as well as projections for current and near-term noble liquid, semiconductor, and scintillator experiments. Finally, I will discuss some new techniques that may allow us to more robustly discriminate between dark matter signatures and background.

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## Gamma-ray Constraints on Decaying Dark Matter and Implications for IceCube

Tuesday Mar 28, 2017
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Utilizing the Fermi measurement of the gamma-ray spectrum toward the Galactic Center, we derive some of the strongest constraints to date on the dark matter (DM) lifetime in the mass range from hundreds of MeV to above an EeV. Our profile-likelihood based analysis relies on 413 weeks of Fermi Pass 8 data from 200 MeV to 2 TeV, along with up-to-date models for diffuse gamma-ray emission within the Milky Way.

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## Bounding Milli-magnetic charged particles

Tuesday Mar 14, 2017
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Just like how milli-electric charged particles can exist, so can milli-magnetic charged particles.  We review simple ways of evading the standard quantization arguments and why there are no model independent constraints on magnetically charged particles, milli-charged or not.  We then provide the first ever model independent bounds coming from magnetar cooling arguments.

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## Relaxion from particle production

Tuesday Mar 07, 2017

Recently a new solution to the hierarchy problem was proposed which makes use of the cosmological evolution of a light scalar field, a scanner, instead of symmetry or anthropic arguments to select a small Higgs mass. In the original proposal this scanner field could be the QCD axion and thus such class of solution became known as relaxion’’.

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## RECENT PUBLIC LECTURE

### Janna Levin: Black Hole Blues and Other Songs from Outer Space

Speaker: Janna Levin