College of Engineering, Design & Computing Events

CEAS seminar, "Compact accelerators for next-generation colliders

| 11:00 AM - 12:15 PM

Aakash Sahai
CU Denver, Electrical Engineering


Particle Accelerators that underlie Colliders such as LHC are widely acknowledged as the tools that will make possible discovery of our Universe’s constitution, only 4% percent of which is known and understood per the latest estimates. These machines use the charge handle of elementary particles to apply electromagnetic force and impart them energy. Since particles in tens of GeV energy range have been accessible to us for several decades, it is quite natural to assume that any new forms of matter or energy such as the predicted dark matter and dark energy that make up the 96% unknown universe is at higher energies. Thus, it is a current open challenge to scale the energy frontier beyond 100s of GeV energy-scale.

This challenge is evident in that the LHC machine at CERN which produced the evidence of Higgs-like particles at 126GeV in 2012 has a 27 km circumference that cost ten billion USD to build and annually requires 1.5 billion USD to operate. Thus, scaling to many hundreds of GeVs would need hundred kilometer-scale accelerator which economics-wise appears to be out of reach of even an international collaboration. The main reason behind this is that the acceleration mechanisms rely on Radio Frequency technology. Although RF accelerator technology has been a reliable workhorse for particle physics since the discovery of subatomic structure, the energy gain it imparts per unit length is limited to around 100 MeV/m. This acceleration gradient limit dictates the size of accelerators. Thus, breaching this peak field barrier is now needed to access the energy frontier while the infrastructure budget is kept within reasonable limits.

Therefore, next generation accelerators need new mechanisms that can overcome the limitations of RF technologies. This seminar will summarize our research on innovation of new mechanisms using lasers, plasmas and solid-state materials and the associated challenges. These innovations promise 100GeV/m to TeV/m acceleration gradients for future particle accelerators and may make possible next generation of particle colliders.


Sahai joined CU Denver after being a research associate with physics department at Imperial College London in UK between 2015 and 2018. Before joining Imperial College, he earned his doctorate in EE (Duke, 2015), MS in EE (Stanford, 2005) and MS in Physics (Indiana University, 2015). Between 2005 and 2010 he was employed as a R&D scientist with various hi-tech companies such as Qualcomm Inc and silicon-valley startups.