ASP Online Seminars: The physics and technology of Compact Light Sources, and their state of the art world-wide

by Prof. Luca Serafini (INFN-Milan)

Tuesday 17 Nov 2026, 14:00 → 15:00 UTC

Abstract:

Compact Light Sources are electron-photon mini-colliders representing a specific family of radiation sources generating X-ray

and gamma-ray mono-chromatic photon beams of advanced characteristics. The word compact refers to the comparison with large sizes

and costs typical of Synchrotron Light Sources (SLS), which encompass the multi-100 meter / multi-100 million dollar orders of magnitude

in infra-structure size and construction cost. Thanks to the adoption of optical photons (typically carried by laser beams), instead of magnetic

field arrangements (dipoles, wigglers, undulators) as in synchrotrons, CLS can radiate in the X-ray photon range using moderate energy

electron beam, in the range 30-150 MeV, whereas synchrotrons need multi-GeV electron beams. As a consequence the size of the electron

accelerator in CLS is much smaller than in SLS. We will discuss the physics of Inverse Compton Scattering (ICS), which is the QED process

ruling the performances of CLS and setting their technological challenges. We will also illustrate the different paradigms of CLS (Linac, Storage

Ring, Energy Recovery Linac) and how they are adopted world-wide in several CLS under operation, in commissioning or under design. The

fields of applications enabled by CLS span from advanced radiological imaging, using mono-chromatic X-rays in the medical field with

micro-tomography and virtual histology techniques, to cultural heritage and archeology oriented non-invasive diagnosis, to crystallography,

to photo-nuclear physics with mono-chromatic gamma-rays. A complete discussion on the applications is developed in the next seminar

by S. Samsam. A good review article of reference is: V. Petrillo et al., State of the Art of High-Flux Compton/Thomson X-ray Sources,

Appl. Sci. 2023, 13, 752. https://doi.org/10.3390/app13020752

 

Bio of the speaker: 

Luca Serafini is an expert of high brightness beams, radiation sources (undulatory and collisional), tertiary beams, Full Inverse Compton Scattering, muon beams for seismology, muonic lenses. He is a retired associate with Istituto Nazionale di Fisica Nucleare - Sezione di Milano (Italy). His main scientific accomplishments are: he derived the RF Transport Matrix, the theory of invariant envelope and emittance compensation in photo-injectors, the velocity bunching technique, the two-way acceleration in ERLs, the EXMP technique for ultra-low emittance muon beams, the Full Inverse Compton Scattering, and ERMES, the new technique for active interrogation of seismogenic faults using high energy muon beams for earthquake forecast. Large scale (TWh) gravitational batteries are also in his present scientific interest. He is co-author of the ASFAP Unesco Report (African Strategy for Fundamental and Applied Physics).