Summer Internship Programme 2019

Oxford Particle Physics is running a Summer Internship Programme for undergraduate physics students. We anticipate taking about 7 students. Priority will be given to students in their second year and above.

Students will work with a supervisor in the department, usually a postdoctoral researcher or lecturer, on a self-contained project. Students are encouraged to take part in department life, joining researchers for coffee and discussions.

The projects run for typically 8 weeks during the Oxford summer vacation. Students will be paid £396.05 per week. The project is full-time but hours can be discussed with your supervisor.

Eligibility

Unfortunately, due to UK visa regulations, all candidates must have existing right to work in the UK.

How to apply

You should email a one-page-only application, in pdf format, to Sue Geddes (sue.geddes@physics.ox.ac.uk) by Sunday of 1st week, 28 April 2019. Students should ask for a short academic reference letter to be emailed by the same date. Offers will be made in mid May 2018.

On your 1-page application you should tell us why you are interested in the programme and which project(s) most interest you. Also include your contact details, your year and course, and contact details (including email) of your academic referee. Please also mention any computer programming experience and any previous research experience that you have had.

You are welcome to informally contact the supervisor(s) to find out more details about the projects that interest you. For any administrative issues, contact Sue Geddes (sue.geddes@physics.ox.ac.uk).

Projects

Gaining sensitivity to electroweak production of Dark Matter at ATLAS

Supervisor: Professor Alan Barr (alan.barr@physics.ox.ac.uk)
Duration: 8 weeks

The LHC has now delivered sufficient luminosity to allow production of low cross-section process: such as direct electroweak production of supersymmetric charginos and sleptons. These then decay promptly to Dark Matter candidates and Standard Model particles. However such processes have backgrounds from other processes such as W+W- production, and in several very interesting cases the LHC experiments have not yet gained sensitivity beyond the limits of the previous LEP experiments. In this project we will investigate whether state-of-the-art machine learning algorithms can help us get sensitivity to these very interesting cases.

Advance accelerator concepts: wakefield acceleration and beam dynamics mediated by the high-impedance periodic surface lattice

Supervisor: Dr Ivan Konoplev (ivan.konoplev@physics.ox.ac.uk)
Duration: 8 weeks

The project is dedicated to theoretical studies of the wake-field formation and its interaction with the electron beam propagating in the vicinity of the high-impedance periodic surface lattice.

If the electron beam propagates above high-impedance periodic surface lattice it excites the wakefield which interacts with the beam leading to the beam density and energy modulations. This phenomena can be used for generation of terahertz radiation as well as beam acceleration. In particular it was recently applied at FACET (SLAC, Stanford University, USA) for the measurements of the longitudinal profile of the femtosecond electron beams. The aim of the project will be understanding of the wakefield excitation and formation on the surface of the lattice as well as study the relativistic electron beam dynamics if such a wakefield is excited.

The project will be divided into two sub-projects: EM wakefield generation and beam dynamics. Each sub-project will take up to 4 weeks to complete.

  1. Study of EM field excitation
  2. Study of beam dynamics in the self-induced fields

The first sub-project will be dedicated to the theoretical studies of the wakefield generation if a relativistic electron beam propagates above the two dimensional periodic surface lattice. Such a surface lattice can be machined on the bulk of the metal and it is ideal for applications in accelerators for beam diagnostics and EM radiation generation. The aim of the sub-project is to develop understanding of the wakefield formation and the periodic surface optimisation for a specific task.

The second sub-project will be focused on the studies of the interaction of the wakefield generated with the relativistic electron beam. The studies will be dedicated to investigations of a single electron dynamics in such field as well as dynamic of group of electron oscillators (electron bunch). Both the wakefield acceleration and the EM field generation will be considered for a specific conditions.

The studies of the beam dynamic as well as the wakefield generation will be carried out using both analytical and numerical methods. Knowledge of Special Relativity, EM theory and capability to write codes using MATLAB or other programming languages are essential.

Software development for and physics exploration with VISualisation of OScillations (VISOS)

Supervisor: Dr Xianguo Lu (xianguo.lu@physics.ox.ac.uk)
Duration: 8 weeks

The software program VISOS (VISualisation of OScillations) is a brand-new project to illustrate neutrino oscillations. Its primary goal is to precisely explain this beyond-Standard-Model physics to the general public in an intuitive manner. It also has an attractive potential to help researchers in the field explore the phenomenology of neutrino oscillations in different parameter space. The initial proof-of-principle stage of the project has been recently concluded with success and one summer student is encouraged to join the second-stage development for software development and/or physics exploration.

The successful candidate for the software development is expected to help design and develop a web-based application of VISOS; the successful candidate for the physics exploration is expected to expand the functionality of VISOS for different physics configurations, closely connected to current and future flagship neutrino experiments.

2nd and 3rd year students with strong interest in neutrino physics and software development are encouraged to apply. Candidates should indicate their software qualifications and project preference in the application.

Absolute distance interferometry using a frequency comb

Supervisor: Professor Armin Reichold (armin.reichold@physics.ox.ac.uk)
Duration: 8 weeks

Frequency scanning interferometry is a technique for absolute distance measurements. In the incarnation referred to as dynamic FSI, developed at Oxford physics, it relies on the ability to measure the frequency of scanning laser using absorption spectroscopy on molecular excitations of gases such as acetylene or hydrogen cyanide. This technique has already generated a patent and four commercial licenses and is currently implemented as an industrial precision instrument (Absolute Multiline) through the German company Etalon AG.

In 2015 FSI measurements were made by Oxford Prof Armin Reichold at the German national institute of standards (PTB) in Braunschweig in which in addition to multiple gas absorption cells and a precision reference interferometer a state of the art, high precision frequency comb was used to record beat-patterns of the scanning lasers with the comb laser. This data has not yet been analysed and has a high potential to enable new ways for improving the spectroscopic methods used in FSI and hence improve the distance measurement accuracy.

This summer projects purpose will be to analyse the data with extensions of existing MATLAB or Fortran codes in a variety of ways among which could be:

  1. Fitting the beat signals of the scanning lasers with the comb to obtain a highly precise frequency axis.
  2. Fitting the positions and widths of the peaks in the absorption spectra with Voigt functions instead of the simpler Gaussian functions used so far.
  3. Potentially performing the fits from 2. using a total chi-squared method in which errors in both axes can be considered.
  4. Comparing the results of the above fits to see how accurately the Gaussian fraction of the width of the peaks can be fit and hence how accurately the pressure of the gas cell can be determined.
  5. Comparing the results of the above fits to measure the relative spacing of the gas cell peaks
  6. Using these results to improve the distance measurement results.

The project is open ended and the data has not been analysed systematically before. How many of the above points can be dealt with depends on the student and on the data. The data analysis aspects demand good analytical skills and good programming skills with some experience in Java preferred because the majority of existing analysis code is in Java.

Depending on the preferences of the students this project could also be directed towards the hardware aspects of the FSI technique. The full hardware for the above experiments (except for the frequency comb) is now available in Oxford together with a new high speed data acquisition system which can extend the capabilities of the technique significantly. Students with a desire to work more on the hardware side of this technique could participate in this aspect.

Inference of the CKM angle gamma

Supervisor: Dr Malcolm John (malcolm.john@physics.ox.ac.uk)
Duration: 8 weeks

The effect of the CP-violating parameter gamma is most readily observed as charge asymmetries in the rate of B mesons decaying to D mesons in so-called tree decays. There are many decay modes of this type and their information must be combined together to obtain the likelihoods for the eventual measurement of gamma. This combination shall be performed by the summer student using (and updating) an existing code to take advantage of modern graphical packages to efficiently deliver graphical information to the user. The student will be asked to develop the code to calculate the current sensitivity to new physics in these types of analyses by adding in an extra (unexpected) degree of freedom and rerunning the inference. Candidates need no prior computing experience, but an interest in developing useful software tools would be an advantage.

High-precision measurement of the W boson mass

Supervisor: Dr Chris Hays (chris.hays@physics.ox.ac.uk)
Duration: 8 weeks

The mass of the W boson is predicted by the Standard Model to a precision of a few parts in 100,000, making it sensitive to quantum corrections from new particles with masses as high as 10 TeV. Ongoing W mass measurements from experiments at the Large Hadron Collider and at the Tevatron Collider will soon achieve a precision of a part in 10,000 per experiment. The dominant uncertainty on these measurements is due to the limited knowledge of the momentum distributions of partons within the colliding protons and antiprotons. This project will study this uncertainty and develop strategies to minimize it. The uncertainty evaluations will be used in a combination of LHC and Tevatron measurements to obtain a world-average W mass with a precision better than a part in 10,000.

Beam studies for the Compact Linear Collider (CLIC) at CERN

Supervisor: Professor Phil Burrows (philip.burrows@physics.ox.ac.uk)
Duration: 8 weeks, starting date ideally around 1st July

The new CLEAR facility – CERN Linear Electron Accelerator for R&D – has been commissioned and first experiments are taking place. The intern will have the opportunity to work on both hardware and simulation studies for operating and upgrading the 220 MeV electron beamline. There are also opportunities for working on novel beam position monitors and high-gradient radio-frequency accelerating cavities.