Since I was about five years old I knew I wanted to do something in an STEM field: I am naturally more inclined towards engineering - design and problem solving - than experimental physics, but do have a penchant for fundamental theory. When chosing a degree, I figured that if I studied physics then I could probably transfer into engineering if I decided physics wasn't for me, but if I studied engineering I was never likely to get into physics. My work at the Large Hadron Collider (LHC) at CERN means I spend my time at the cutting edge of both physics and engineering: the best of both worlds - my perfect job!
I first joined Imperial College as an undergraduate in 2001 undertaking the undergraduate masters (MSci) course in physics. As part of this course I was drawn toward and undertook studies in such fields as Advanced Particle Physics, Quantum Field Theory, Quantum Theory of Matter, General Relativity and Mathematical Foundations of Quantum Mechanics, but also toward the more “hands-on” Microprocessor and Digital Electronics course. It was through this latter course that I became acquainted with Dr. Costas Foudas, who would go on to be my supervisor for both my master’s project and for my doctoral studies.
My master’s project (2004-2005) was a study of a conceptual tracking trigger for high-luminosity upgrades of the LHC. The concept under investigation was the so-called “Calorimeter-Seeded Tracker Readout”, whereby the Calorimeter trigger would select regions of interest within the tracker which would then be read out. This project successfully demonstrated that such an approach was infeasible within the stated constraints and, more importantly, highlighted the key factors and limitations for any tracking trigger design. This work was presented in CERN in the summer of 2005, and contributed to my being awarded a First-Class Degree.
The first half of my doctoral studies (2006-2008) was on the design, construction and installation of the Global Calorimeter Trigger at CMS. This work involved the development and testing of FPGA-based electronics and opto-electronics, writing firmware and the software infrastructure for controlling the hardware and integrating it into the larger control framework. The second half of my doctoral studies (2008-2009) was the development of a conceptual tracking trigger based on the conclusions of my master’s dissertation. The so-called “Stacked Tracker” concept, whereby two silicon layers are placed in close proximity to identify high-pT tracks on-detector, was studied and shown to be an effective means of building a tracker with which to provide candidates for a tracking trigger. This concept has since become the baseline design for the CMS tracker at the HL-LHC.
Since 2009, I have continued to work on the CMS experiment as a researcher in the Imperial College HEP group, specifically focussing on upgrading the Calorimeter trigger. This work included studies into the implicit assumptions that went into the design of the existing trigger and promoted an alternative architecture, the so called Time-Multiplexed trigger, which overcame many of the limitations of the existing system and which has now been adopted for the upgraded calorimeter trigger. As part of the implementation of this upgrade, I was involved in the design and implementation of the MP7-processor card, a 1Tb/s optical-stream processor, which is the foundation of the upgraded Calorimeter trigger, but which has also been adopted as the hardware platform for the upgrades of many other systems within CMS. To control the MP7 and other new hardware, I co-developed the IPbus control protocol and implemented the uHAL software library for controlling hardware, which has since been adopted as the standardized control mechanism not only for upgrades at CMS, but all the experiments at the LHC, and also for several new, non CERN-based experiments.
In the last four years, I have supervised several UROP (summer-placement) students, two of whom have gone on to doctoral studies in particle physics. I have also successfully applied for CASE-studentship funding to study new techniques for programming FPGAs for use in particle physics and am currently supervising a doctoral student in that post.
I have presented my work at several international conferences and been published in the accompanying proceedings, and in 2014 I was invited to speak at the inaugural “High-Performance Signal Processing” conference, which aims to transfer knowledge and ideas regarding real-time data-processing between astro- and particle- physicists.
In 2014, I was awarded the CMS Achievement Award for early work on the implementation of a tracking trigger and for the development and implementation of the Time-Multiplexed architecture and algorithms for the Calorimeter Trigger.
In 2015, I was awarded the CMS Spokesperson’s Medal and Prize for Young Researcher 2015, citing my ‘sustained and critical contributions to the Global Calorimeter Trigger, to the development of the Time-Multiplexed Trigger Architecture for Run 2, the innovative implementation of new physics algorithms in highly constrained firmware and the role in the design and implementation of the MP7 processor board.’
Rose A, Development and testing of an upgrade to the CMS level-1 calorimeter trigger, Topical Workshop on Electronics in Particle Physics (TWEPP)
Rose A, The MP7 and CTP-6: multi-hundred Gbps processing boards for calorimeter trigger upgrades at CMS, Topical Workshop on Electronics in Particle Physics (TWEPP)