CERN Accelerating science

10th PATRAS Workshop on Axions, WIMPs and WISPs

The first PATRAS Workshop took place at CERN in 2005. Last July, it returned to CERN for its tenth anniversary.

The initial aim of this series of workshops was to provide academic training to the new generations of scientists working within the EU - ILIAS network, which covered the already mature field of astroparticle physics. Following the increasing worldwide interest in the workshop, the organizers widened its agenda. Inspired by the possibilities that are opening up in ongoing searches for exotica like axions, WIMPs, etc, the first appearing as a byproduct of Peccei and Quinn’s efforts to solve the strong CP-problem in the Standard Model and the second being theoretically motivated within supersymmetry, other candidate particles of the mysterious dark sector with related properties came to the focus of experiment and theory alike. Results from direct and indirect searches for axion-like particles (ALPs) dubbed also as weakly interacting slim (light) particles (WISPs) and new more sensitive searches for EDMs were covered during the workshop.

This year, the speakers of the workshop covered diverse new approaches in dark matter, dark energy, neutrino physics, including astrophysical observations as well as novel detection ideas with state-of-the-art instrumentation. CERN’s General Director, Rolf Heuer, who delivered the opening address to the workshop, emphasized that following the discovery of the Higgs Boson we are confronted with big questions related to the hidden side of our universe. During the five days, the workshop participants from more than forty Institutions worldwide had the opportunity to present their latest research results, discuss the latest detector upgrade plans and new exciting ideas for future research. It is worth noting that due to the high number of participants, a poster session took place for the first time during the workshop.

The talks demonstrated the experimental breadth in searches for dark matter and dark energy constituents, which covered an admittedly huge parameter phase space from direct searches for WIMPs in lowest noise underground experiments, axion or WISPs searches with cavity and light shining through wall experiments, the not so indirect searches with orbiting equipment in specific solar or cosmic observations, to searches at the LHC. Also hidden photons / gauge bosons of various kinds are being searched for with accelerators and solar observations. Theories span even wider breadth, which is evident from merely considering the mass range of the expected exotica.

The PATRAS programme traditionally features recent results, new theoretical ideas, and exciting projects in particle and astroparticle physics, beyond the main focus of the conference. Space X-ray missions like the Indian SOXs and the Chinese Chang 'E1 presented their latest results. Both missions re-analyse their data searching for overlooked signatures of dark matter, or, dark energy constituents like the chameleons from the sun, in their solar X-ray observations. 

During the 10th edition of the workshop, the experiments presented along with their results also their upgrade plans. The experimental techniques either in use or being suggested to unravel the nature of the enigmatic dark sector are advancing impressively. It was noticed in the workshop the remarkable physics overlap between LHC and astroparticle physics. Interestingly, the novel state-of-the-art equipment used face two extreme situations: the LHC experiments with their unprecedented high background rate, and the dark matter / dark energy searches with the low signal level requiring an ever increasing background screening. It is worth stressing that sophisticated equipment that was developed for high energy physics experiments finds more and more applications in astroparticle physics. Micromegas detectors, powerful magnets used in the LHC, highly sensitive antennae in the sub-eV range, etc., are typical for the highly interdisciplinary character of a wide range of experiments to be upgraded or in the conceptual design phase.

In the spirit of this workshop series, discussions were lively and the atmosphere very friendly though occasionally not without scientific controversy. A number of new ideas were presented, mostly being highly interdisciplinary in character, profiting from the strong synergies developed between theory and experiment. By bringing together experts working on so many diverse topics, the workshop contributes towards the ongoing scientific revolution in the field of particle astro-physics, which will uncover the unknown Universe we live in. Stay tuned!   

More information can be found at the PATRAS workshop website: axion-wimp2014.desy.de