Physics and Astronomy

Particle Physics research placements

At Sussex, you learn from experts working at the forefront of physics. This means you study modules based on the latest research, whilst exploring the fundamental laws of physics. In the research placement programme, you will have the opportunity to directly experience world-leading physics research through paid placements in active research groups during the summer holidays. This unique experience will give you a significant advantage when you apply for jobs, either in academia or in industry.

EDM - Can you run the Universe backwards?

Faculty advisors: Philip Harris, Simon Peeters, Michael Hardiman

The Cryogenic Neutron Electric Dipole Moment (EDM) Experiment is a unique experiment located in Grenoble, France, which uses incredibly precise measurements of the charge distribution in the neutron to test the symmetry of the laws of physics under time reversal. EDM will help us answer the question of why the Universe is full of matter rather than antimatter. You will work on the technically challenging development of either the high-voltage supply or the magnetic shielding, both of which need to function at temperatures close to absolute zero, or on computer simulations and data acquisition/analysis. Subject to the availability of funding, there is the possibility of spending some time at the experimental site in Grenoble.

Looking for direct evidence for Dark Matter

Faculty advisor: Simon Peeters

DEAP/CLEAN is a world-leading experiment that looks for direct evidence of Dark Matter in the Universe by trying to detect the interaction with its 3600 kg liquid Argon target. DEAP-3600 is currently under construction in SNOLAB, located 2km underground in a Canadian nickel mine.

Your project could be in one of two areas: laboratory based work on an optical calibration system for the photomultiplier tubes; or a software based project analysing data and determining the best way to search for this mysterious form of matter.

Measuring the neutrino mass with SNO+

Faculty advisors: Jeff Hartnell, Lisa Falk, Simon Peeters

SNO+ is an extremely innovative experiment that uses 800 tons of a special light emitting oil surrounded by nearly 9,000 photomultiplier tubes (light sensitive devices capable of detecting single photons that are worth millions of pounds in total). The SNO+ detector is buried 2km underground in a Canadian nickel mine and we are using it to search for an extremely rare process called neutrinoless double beta decay. If we can discover these radioactive decays it will tell us whether the neutrino is its own antiparticle and what its mass is.

Your project could be in one of two areas: laboratory based work on an optical calibration system for the photomultiplier tubes; or a software based project analysing data and determining the best way to search for and measure these rare decays.

Performance studies for an upgrade of the ATLAS trigger (in collaboration with Dr Mark Sutton - Sussex)

Faculty advisor: Fabrizio Salvatore

The ATLAS experiment is one of the two general purpose experiments currently taking data at the Large Hadron Collider (LHC) at CERN. In parallel to the analysis of the data presently collected by the experiment, there is a growing interest in studying the performance of the ATLAS detector once the LHC luminosity (i.e. interaction rate) will be increased by at least an order of magnitude with respect to the current value. In particular, there is growing interest in studying the rate of events that the ATLAS detector can record ("trigger" rate). The student will analyze ATLAS Monte Carlo data to look at ATLAS trigger rates at different luminosities and devise possible strategies to improve these rates in an upgraded LHC environment.

Supersymmetry Searches at ATLAS

Faculty advisors: Antonella De Santo, Fabrizio Salvatore

The Large Hadron Collider (LHC) at CERN, near Geneva, Switzerland, collides protons of unprecedented high energies, recreating conditions thought to have existed in our Universe shortly after the Big Bang. The ATLAS detector is one of the two multi-purpose experiments at the LHC, designed to unveil evidence for new phenomena  beyond the Standard Model (BSM) of particle physics. Supersymmetry (SUSY) is one of the well-motivated BSM theories that could be realised in nature at LHC energies. SUSY could for example hold the key to explaining the nature of Dark Matter in our universe. The Sussex ATLAS group has a leading role in the search for supersymmetric signals in leptonic final states at ATLAS.

You will become integrated within the Sussex ATLAS group for the duration of your project, interacting collaboratively on a daily basis with faculty members, research staff and other students. You will perform a computer-based analysis of ATLAS data, including from simulations, with the aim to contribute to the search for SUSY signals  at the LHC. The scope of the physics content of your project will be adapted to your pre-knowledge of particle physics. If you are not already a proficient programmer, you will be expected to acquire rapidly the computing skills (eg C++ programming and ROOT analysis framework) necessary to complete your project successfully. A good disposition towards teamwork is also essential.

Warped Extra-dimensional models

Faculty advisor: Veronica Sanz

In this project the student will learn about theories with new dimensions of space-time, and implement in Feynrules (a Mathematica package) the interactions of a very attractive model for the Large Hadron Collider, the bulk Randall-Sundrum model.

Radon emanation measurements

Faculty advisor: Simon Peeters

The next generation of particle physics experiments such as SNO+ and DEAP3600 have extremely stringent requirements on the backgrounds. One of the biggest concerns is 222Rn, which emanates from most materials at a level that would impact the physics. During this project, you will be learning about radioactive backgrounds in materials and developing a set-up to test the emanation of this and determining its sensitivity.

The student will be involved in mostly laboratory work, using pure gases, vacuum and radioactivity measurements.

The physics of flavour with the ATLAS experiment

Faculty advisor: Alessandro Cerri

The Large Hadron Collider is colliding protons at the highest energies ever achieved in a man-made experiment. This allows us to perfect our understanding of the dynamics of the tiniest constituents of matter, as well as that of the evolution of our universe.

These understandings often happen through precision investigations of phenomena that are already known, like the so called "flavour sector" of particle physics: this is the sector that describes the behaviour and evolution of quarks, nowadays focusing mostly on beauty and charm.

Flavour physics is indeed an ideal precision ground to look for indirect concrete evidences of new physics and the ATLAS experiment has collected a large amount of data which can be used to investigate and constrain these contributions, in a physics context which is rich, fruitful and well understood. Measurements can range from precision determinations of particle properties (production mechanisms, lifetimes etc.) to the search and identification of properties of new particles: the ATLAS heavy flavour group (led by Dr Cerri) is in fact the one responsible for the very first new particle discovered at the LHC.

In contributing to a study in this topic, you will learn the basic tools of experimental measurements in particle physics: data analysis, statistical methods and the simple beauty of this sector of particle physics.

Fast trajectory reconstruction and retina-like algorithms

Faculty advisor: Alessandro Cerri

We often learn how to better address a practical problem from the methods that nature has selected in the biological world.

The aim of this project is that of applying line-identification techniques known to exist in the human visual cortex to a very common problem in particle physics: the identification of charged particle trajectories from the position of passage as detected by "tracking detectors" (devices capable of measuring with a given accuracy the passage of particles through a sensitive plane or volume). This is a very innovative technique which is still not fully explored. Its application to the ATLAS detector at the CERN Large Hadron Collider could prove to be a novel interesting inter-disciplinary application of the biology of human vision.

The high parallelism and locality of this kind of algorithm is well suited for devices like Graphics Processing Units, capable of "embarrassingly parrallel" computations. The aim of this project is that of developing and testing prototype algorithms on such a platform, and evaluate their performances compared to other strategies commonly used to address this kind of problem.

This project is more suitable for a student with a keen interest in low-level programming of advanced digital electronic devices, in particular advanced graphics processors (GPU) and the CUDA platform. Familiarity with the Linux operating system, C/C++ programming and the basics of particle detection techniques are a major asset.

Magnetic and electric field development for neutron EDM measurement

Faculty advisor: Clark Griffith

The discovery of a nonzero permanent electric dipole moment (EDM) of the neutron would violate time-reversal symmetry, and would be a signature of new physics beyond the standard model. EDM measurements are especially sensitive to additional CP violating phases that are required to explain the matter antimatter asymmetry that we observe in our universe. Such phases could possibly be generated in supersymmetric extensions of the standard model. The experimental technique is to carry out extremely precise magnetic resonance measurements on stored ultracold neutrons while applying a strong electric field. The EDM sensitivity crucially depends on being able to apply as large an electric field as possible, and having an ultra-stable and uniform magnetic field.

This project will involve hands-on, experimental laboratory work related to developing apparatus to generate and measure the electric and magnetic fields required for the experiment. Depending on the interests of the student, the project could also include computer modelling of the field environment.