Temporary website of Hugo Day

As you've probably guessed from following any of the links to this website, I'm presently a PhD student at the University of Manchester/Cockcroft Institute/CERN studying accelerator physics. More specifically kicker magnet impedance. More specifically, there's an abstract at the bottom of the page. Hopefully this website will eventually have somewhat more detail on it, but that'll be when I have the time to stop doing the work and start describing it.

Papers for IPAC'12

Posters for IPAC'12

Beam Coupling Impedance Reduction Techniques of CERN Kickers and Collimators

Supervisor: E. Metral (CERN) and R.M. Jones (Cockcroft Institute and University of Manchester)

Co-supervisors: F. Caspers and M. Barnes (CERN)

Plans for the LHC experimental runs call for a maximisation of the luminousity of the colliding beams to provide the optimum conditions for data collection in the 6 experimental apparatuses. One of the methods to be applied to increase the luminousity is to decrease the cross sectional area of the proton bunches. One method of doing this is to reduce the beam impedance that bunches experience during their circulation in the LHC.

Current models of the CERN accelerator system attribute a significant proportion of the beam impedance to either the kicker magnet systems (highly prevalent in the SPS) or the beam collimators (expected to dominant in the LHC), so present attempts at reducing the beam impedance, both longitudinal and transverse, are focused on these components. To properly understand the causes of beam impedance, and to design effective counter-measures to its effects, accurate models of beam impedance must be developed and applied to structures within the accelerating structures. These models can then subsequently be used to design appropriate impedance reduction techniques.

Current beam impedance models using simple rectangular geometries are suitable for determining the approximate behaviour of unscreened components, but are incapable of explaining the multitude of resonances that are observed in the real equipment. These resonances have been thought to be responsible for a multitude of potential problems in kicker magnet systems, such as reduced rise times, affecting the field-top flatness during operation and causing periodic heating in the magnets, potentially above the Curie temperature and thus threatening the effective operation of the magnets. Collimators are thought to be the primary source of transverse impedance in the LHC, and as such finding efficacious screening methods for them whilst allowing them to continue their designed function would be of great benefit to improved operation of the LHC.

The project is aimed at first developing a comprehensive understanding of the mechanisms behind the existing known resonances and operations of the kicker magnets and collimator systems, through a use of theoretical description, computational simulation and experimental measurements. Subsequent to this, further measurements will be made of other magnet systems and collimators to allow a comparison of alternative construction methods; ferrite-loaded magnets, laminated steel-strip magnets, and the existing theoretical models (predominantly assume a continuous aperture of a uniform material). From this comparison it is expected to understand the different sources of resonant phenomena from the components, and if possible expand upon existing/develop new models to more accurately describe the phenomenon observed.

From this base it is expected to analyse a variety of potential impedance reduction methods, using data for existing methods (using beam screens (LHC MKI injector magnets), implementing serigraphy on internal wall of components (SPS MKE extractor magnets)) to determine which solutions may be most effective to be applied to both existing systems, and also to help in the design of future accelerator components.

Research Interests

My research interests are rather broad, however my current interests are focused on accelerator research, both of beam interactions, beam surroundings and novel accelerator technologies.

Outside of accelerator physics, my interests focus on plasma/EM phenomena - fusion research and the "Space Environment" being two key areas. I take a more general interest in physical medical therapies and complex systems from extension of my main interests. Fluid mechanics, of both low and high Reynolds' numbers, laminar to turbulent flow transition and traffic simulation are subjects of specific interest. Energy policy is another.

What I do in my spare time

Just a list for now

Past Education

2005-2009: MPhys Physics (Hons) at the University of Southampton.

Master's Project - Synthesis and characterisation of branched gold nanoparticles using a wet chemical synthesis method. Branched gold nanoparticles of core size 10-100nm were produced with branch sizes ~10s of nm were produced using a surfactant guided reduction reaction scheme. These branches were characterised for absorption properties and physical dimensions. The reaction mechanism was derived through systematic control of the reaction scheme. This work resulted in the following publiction Controlling the three-dimensional morphology of nanocrystals, H. Day, D. Bartczak, N. Fairburn, E. McGuire, M. Ardakani, A. Porter, A. Kanaras, CrystEngComm, 2010, 12 (12), 4312 - 4316

Dissertation - The effects of Geomagnetically Induced Currents (GICs) on Earth based transmission lines. The causes, effects and potential solutions to GICs and their interactions with transmission lines (gas pipelines and power transmission systems) were investigated through a comprehensive literiture review and some personal calculations.