Feb 9th C-AD seminar

I can give a talk that covers both topics, in fact, as parts of the Japan trip were also about ion traps.

Title: "Ultra-low emittance beams in ion traps and lab visits in Japan"

Abstract:
Laser-cooled ion traps are used to prepare groups of ions in very low temperature states, exhibiting such phenomena as Coulomb crystallization.  This corresponds to very small normalized RMS emittances of 10^-13–-10^-12 m, compared to typical accelerator ion sources in the 10^-7–-10^-6 m range.  Such bunches could potentially be focused a million times smaller, compensating for the lower number of ions per bunch.  Novel high density focal points using only a single bunch also appear possible, where the high density particles collide with themselves.  At ~TeV energies, these approach the nuclear density and may offer a way of studying larger quantities of neutron star matter and other custom nuclear matter in the lab.
A trip to Japan in November 2023 visited five labs including the Hiroshima University Beam Physics Laboratory, where Coulomb crystallisation of Ca+ ions is routinely achieved.  Other destinations included the Compact ERL (cERL) at KEK, the J-PARC 30GeV main ring, and fixed-field accelerators at Kyoto University Institute for Integrated Radiation and Nuclear Science (KURNS) and Kyushu University.  Some technical highlights and photos from these visits will be shown.


Bio:
Stephen Brooks is a physicist at Brookhaven National Laboratory in the United States, and previously worked at Rutherford Appleton Laboratory in the United Kingdom until 2013.  His doctorate thesis was on particle capture from the neutrino factory target and he later moved on to the design of fixed-field accelerators.  These accelerators require custom magnetic field profiles, which led to an interest in magnet design.  In 2018, he designed and supervised the construction of the permanent magnets for the CBETA 4-turn fixed-field ERL at Cornell University and participated in its commissioning.  A common theme throughout his research is optimisation and automatic design techniques.