IPPP Summer Studentships 2019:
The IPPP will offer the possibility for students (preferably Year 3) of working on a project in theoretical particle physics for about three weeks in Summer 2019. The topics and the names of the supervisors are given below. The exact dates can be agreed individually with the supervisor; successful applicants will receive 100 pounds per week from the IPPP. In the previous years this turned out to be a very successful program. Time by time the summer projects even run into publications, or click here.
If you are interested then please send an email with a ranking of your favourite projects to daniel.maitre@durham.ac.uk.
The deadline for the application is 3rd March 2019.
Simon Badger Understanding the physics of scattering amplitudes
Scattering amplitudes are the fundamental building block in Quantum Field Theory that enable us to predict result measured in high energy collider experiments. This project will introduce some of the basic ingredients needed for describing the scattering of gluons – the mediator of the strong force – and show how amplitudes that seem impossible at first sight, are found to have extremely simple expression.
David Cerdeño Dark Matter
Astrophysical and cosmological evidence indicates that the majority of the matter in the Universe takes the form of non-luminous particles known as dark matter. Detecting these particles in underground detectors might be possible but it is extremely challenging. In this project we will investigate methods to discriminate dark matter signals from neutrino interactions in this kind of experiments.
Frank Krauss and Marek Schönherr Automated Calculation of Dark Matter Annihilation Rates
An important particle physics input for cosmology is the calculation of annihilation rates of possible Dark Matter candidates. Such cross section calculations have been fully automated in a variety of frameworks in perturbation theory. A framework for this is also available in the SHERPA program that is being developed at IPPP. In this project the student will adapt the framework to Dark Matter annihilation rates, by supplementing the code with the thermal spectrum of Dark Matter particles. The code is written in C++, so the student needs to be sufficiently familiar with this programming language.
Alexander Lenz New physics around the corner?
Experiments running currently at the Large Hadron Collider at CERN have obtained first hints for deviations of measurements from the predictions of the Standard Model of Particle Physics. In the summer project these anomalous observables will be investigated and ideas for how to extend the Standard Model will be searched for..
References:
Overview talk of Flavour Physics
Lecture notes for Flavour Physics
Daniel Maitre Software development
The goal of this project is to develop a library to deal with histograms that retain error correlation information. The project can either start from existing code and modernize it or start from scratch. The library should be written in c++ with Python bindings. This project requires some familiarity with c++ and python, but does not require experience in mixing both.
Silvia Pascoli Sterile neutrinos: truth or fiction?
Neutrinos are the most elusive of the fundamental components of the Universe. But they provide us with the only particle physics evidence that the current and very successful picture of particles and their interactions, the Standard Model, is not the ultimate answer. Something is missing and is required to explain why neutrinos have, albeit tiny, masses. Some even more puzzling pieces of information are emerging. Some experiments seem to indicate that there exists a new type of neutrinos, called sterile neutrinos, which do not interact via the four known forces but can manifest themselves in neutrino oscillation experiments. This project will focus on the still-controversial experimental hints in favour and against sterile neutrinos and will try to compose a coherent theoretical picture. Results from the Neutrino 2018 conference, in June 2018, will also be considered as well as the tests at the now-starting programme SBN at Fermilab.
Michael Spannowsky BSM and Machine Learning
1) Electroweak scale model building has undergone a significant change since the discovery of the Higgs boson in 2012. Supersymmetric model-building has been shifted out of the focus and has been replaced by other ideas, such as the Relaxion, the Clockwork mechanism or composite Higgs models. We will review some of these models and study how they can be searched for at future colliders.
2) Machine-learning techniques have become of increasing importance in various applications for particle physics theory. We will study and develop Neural Networks to improve the classification of data sets. We will try to perform a fit using machine learning methods. A very good understanding of python is needed to be able to work on this project.
IPPP Summer Studentships 2018:
The IPPP will offer the possibility of working on a project in theoretical particle physics for about three weeks in Summer 2018. The topic and the names of the supervisors are given below. The exact dates can be agreed individually with the supervisor; successful applicants will receive 100 pounds per week from the IPPP. In the previous years this turned out to be a very successful program. Three years ago some of the students managed even to write a publication. Durham students should apply via the Physics department webpage, non-Durham students please contact alexander.lenz@durham.ac.uk.
The deadline for the application is 27th March 2018.
Simon Badger and Fabrizio Caola – Finding new physics in the Higgs sector
With no direct sign of new physics at the LHC so far, search for subtle
deviations from the Standard Model is becoming an essential task.
A useful and popular framework to perform these studies is provided by
effective field theory (EFT) techniques, which allow to study many
different beyond the standard model (BSM) scenarios at once, with only
few theoretical assumptions.
The aim of this project is to first understand the EFT theoretical
framework, and then apply it to key Higgs processes at present and
future colliders.
Silvia Pascoli – Sterile neutrinos: truth or fiction?
Neutrinos are the most elusive of the fundamental components of the Universe. But they provide us with the only particle physics evidence that the current and very successful picture of particles and their interactions, the Standard Model, is not the ultimate answer. Something is missing and is required to explain why neutrinos have, albeit tiny, masses. Some even more puzzling pieces of information are emerging. Some experiments seem to indicate that there exists a new type of neutrinos, called sterile neutrinos, which do not interact via the four known forces but can manifest themselves in neutrino oscillation experiments. This project will focus on the still-controversial experimental hints in favour and against sterile neutrinos and will try to compose a coherent theoretical picture. Results from the Neutrino 2018 conference, in June 2018, will also be considered as well as the tests at the now-starting programme SBN at Fermilab.
David Cerdeno – Introduction to the detection of dark matter particles
Astrophysical and cosmological evidence indicates that the majority of the matter in the Universe takes the form of non-luminous particles known as dark matter. The detection and identification of this new kind of matter constitutes one of the main open problems in modern Astroparticle Physics. In this project we will investigate ways to detect these particles in experiments on Earth, through their collisions with a target material.
Alexander Lenz, Luca DiLuzio – Introduction to grand unified theories
Various features of the Standard Model of elementary particles point to a deeper structure in which the strong and electroweak forces are unified. In this project, we shall pass through the motivation for extending the SU(3)xSU(2)xU(1) gauge symmetry of the Standard Model to a simple or semi-simple gauge group, which would eventually leave us with two basic classes of unified frameworks – the SU(5) grand unification and the left-right symmetric models involving namely the Pati-Salam and SO(10) scenarios. We shall consider some of the consequences of embedding the Standard Model into such unified theories, like the unification of gauge and Yukawa couplings at some very high scale, the implications for neutrino masses and baryon stability. While an elementary knowledge of quantum field theory and group theory is welcome, the project will be tuned to the student’s level.
Michael Spannowsky, Ramona Gröber – The Higgs sector beyond the Standard Model:
The Higgs boson, discovered in 2012, was the last missing ingredient of the Standard Model.
This now opens up the possibility for a precise understanding of the origin of particle’s masses
and the mechanism of electroweak symmetry breaking. Since the Higgs boson is the only
spin-0 particle of the Standard Model, one can ask the question whether the Higgs sector might be
extended and whether such an extensions can be related to yet unsolved issues of the Standard Model.
In this project we will investigate the Higgs sector of the
Standard Model and extensions and how it can be probed at the LHC.
Steven Abel, Jakub Scholtz – Constraints on Andromeda DM halo ellipticity from its Plane of Satellites
It appears that 15 out of ~30 satellite galaxies of the Andromeda lie in a very narrow plane (width ~ 20 kpc, radius ~ 200kpc). If the dark matter halo of Andromeda were sufficiently elliptical, then the spherical symmetry breaking terms would lead to angular momentum non-conservation and randomize the orbits of the satellites that were originally all in one plane. As a result the existence of this plane of satellites can be interpreted as a bound on the ellipticity of the dark matter halo.
A summer student could determine the orbits of these satellites in a non-spherical halo using GalPot — a scientific software that is designed to integrate the orbits. Once the student is familiar with GalPot, we would scan over a range of ellipticities and orientations of the triaxial halo and determine which configurations lead to significant losses of planarity. These configurations are then ruled out. The creative research element comes from determining a reasonable criterion that determines the loss of planarity. I would think that growth of the standard deviation of unit angular momentum vectors of the satellite population would work, but I would like the student to come up with their own ideas in this regard.
Frank Krauss, Jonas Lindert – Top-quark reconstruction in ttbb production at the Large Hadron Collider
Precise measurements of Higgs boson production in association with top-quark pairs
allow for constraints on the top-quark Yukawa coupling, which in turn is crucial to fully
characterise the scalar sector of the Standard Model and could also open a window on
Beyond-the-Standard-Model interactions. At the Large Hadron Collider, searches for
ttH production in the dominant H -> b bar channel are plagued by a large QCD background,
which is dominated by ttbb production. The detailed understanding of this
multi-particle background process is of crucial importance for the sensitivity of ttH(->b bar)
analyses. In this project we will employ state-of-the art simulation software
including higher-orders in perturbation theory for the modeling of ttbb and will
investigate and compare different analyses techniques for the identification of
top-quark candidates in ttbb production. In particular we want to develop a strategy
based on Machine Learning techniques to separate b-quarks originating in the hard process
against b-quarks from top-quark decays.
