Beam-beam and crab cavity proton dynamics for the LHC luminosity upgrade

The luminosity upgrade of the Large Hadron Collider will increase the delivered instantaneous luminosity by an order of magnitude to search for new, rare, particles and perform precision measurements of the standard model of particle physics. The machine challenges are significant, including unprecedented understanding of the beam dynamics, high intensity collimation and the use of crab RF cavities. The project has entered a construction phase and there are key research and development beam physics’ studies needed to consolidate the performance of the baseline scenarios and to assess potential further improvements.

The high brightness beams for HL-LHC operate the machine in a challenging and potentially limiting regime. The presence of the beam-beam interaction, with the crab cavities, machine non-linearities and other constraints will limit the stable motion and ultimately the luminosity performance of HL-LHC. During LHC Run 3 high brightness beams will be available from the injectors allowing validation of the beam-beam models developed so far at CERN and in the UK. Coupled with this is the need for effective halo control in this environment, and the deployment of novel hollow electron lenses and crystals to control the halo.

A 3.5-year PhD studentships is available under the supervision of Prof Rob Appleby (Department of Physics and Astronomy, University of Manchester and Cockcroft Institute) and Dr Guido Sterbini, Dr Stefano Redaelli (CERN) to develop beam-beam simulations including machine non-linearities and noise for HL-LHC to explore proton long-term stability, halo evolution and machine performance. This student will create new tools for proton dynamics and perform data analysis for the follow-up of the beam and luminosity lifetime during the LHC run. These studies will be used to refine the operational scenario of HL-LHC and test various options in simulations and machine developments. Additional information concerning the magnet field quality and the crab- cavity will become available as the post progresses, along with new models for the halo control of hollow electron lenses. The student will participate to machine studies during LHC Run 3.

These studies will be used to refine the operational scenario of HL-LHC, test various options in simulations and machine developments and make parameter constraints. The student will apply these tools to the study of halo evolution with hollow electron lenses. The PhD project work will hence be a mixture of theoretical, computational and experimental work on the LHC. Full training in beam dynamics and LHC machine physics will be given.

The project is part of HL-LHC-UK, the UK project to deliver key R&D and hardware to HL-LHC in the areas of HL-LHC in beam dynamics, collimation, crab cavities, diagnostics, cold powering and surface treatments. The student will join a vibrant and supportive UK-wide team and will be based in the UK. There will be an opportunity to spend some time at CERN.

The applicant will be expected to have a first or upper second-class degree in physics or other appropriate qualification. Computational experience is desirable but not essential, as is experience in accelerator physics. A full graduate programme of training and development is provided by the Cockcroft Institute. The student will be based primarily at the Institute at Daresbury, with some work at CERN. A willingness to travel to international conferences is desirable.

Potential applicants are encouraged to contact Prof Rob Appleby (robert.appleby@manchester.ac.uk) for more information.

You can find out more about being a PhD student at the Cockcroft Institute here, where you can download an application form and also find out about the other PhD projects available at the Cockcroft. To apply for this project, fill in the application form and email it with your CV to janis.davidson@stfc.ac.uk.

This position will remain open until filled.