DiRAC-3 Operations 2023-26 - Leicester Additional Grant

The DiRAC High Performance Computing (HPC) facility provides cutting-edge computing services for the STFC theory communities in particle physics, astrophysics, cosmology and nuclear physics. Our complementary programmes of HPC skills training and innovation activities provide further support to the STFC theory research programme, as well as delivering significant benefits to wider society and the economy.

Physicists across the astrophysics, cosmology, nuclear and particle physics communities are focussed
on understanding how the Universe works at a very fundamental level. The distance scales
with which they work vary by more than 40 orders of magnitude from the smallest distances probed
by experiments at the Large Hadron Collider, deep within the atomic
nucleus, to the largest scale galaxy clusters observed in the Universe. The science challenges,
however, are linked through questions such as: How did the Universe begin and how is it evolving?
and What are the fundamental constituents and fabric of the Universe and how do they interact?

Progress requires a combination of new astronomical observations, new experimental data and new theoretical insights. Today, theoretical understanding comes increasingly from large-scale
computations that allow us to confront, in detail, the implications of our theoretical models with data from observations or experiments, or to interrogate the data to extract information that has
impact on our theories. Increasingly, theoretical calculations use artificial intelligence and machine learning algorithms to enhance their physical realism, improve their computational efficiency, or both.
These computations require the performance of the fastest computers available and push the boundaries of technology in this sector. They also provide an excellent
environment for training students in state-of-the-art techniques for code optimisation, data mining and visualisation; all valuable skills for their future careers.

The DiRAC HPC facility has been operating since 2009, providing computing resources for theoretical research
in all areas of particle physics, astrophysics, cosmology and nuclear physics supported by STFC. It is a highly productive
facility, supporting the STFC theory community in publishing over 270 papers annually in international, peer-reviewed journals.

In 2020, DiRAC received a £20m capital investment from the UKRI World Class Laboratories fund, allowing the deployment of DiRAC-3 Phase 1, the first major uplift in our
computational resources since DiRAC-2 in 2012 and providing a vital boost to the STFC theory programme for 2022/23.

The main purpose of the funding requested in this proposal is to support the continued operation of the DiRAC HPC facility for the period 2023-2026, including staff and power costs. These resources will enable DiRAC to continue sustainably as an internationally competitive computing facility for the STFC theory community, to train the next generation of leading computational scientists and to play a lead role in the UKRI Digital Research Infrastructure over the next decade.