Postdoc Andrea Gallo Rosso, The Department of Physics. Photo: Gunilla Häggström.

The history of the elusive axions

Axions are hypothetical particles, theorized in the late 70s by particle physicists Roberto Peccei and Helen Quinn (and later, SU professor Frank Wilczek and Steven Weinberg) in order to solve (or clean up) theoretical issues within the Standard Model of particle physics. This explains their name, borrowed from a brand of detergent, according to its inventor Frank Wilczek.  If they exist, their presence in the universe could also solve the problem of dark matter, one of the most important open questions in the field of particle and astroparticle physics. The ALPHA experiment (Axion Longitudinal Plasma HAloscope) aims to detect cosmological axions in the controlled environment of a lab. In this case, Sloane Laboratory at Yale (USA).

Building the detector with potential to detect axions

The ALPHA consortium is working to discover the axion and help explain the underlying structure of the universe. By using a filamentary metamaterial to create an artificial plasma with designer properties, ALPHA will create a kind of ‘radio’ that can capture the dark matter of the axion.
“With this funding and also the previous funding from the Knut and Alice Wallenberg Foundation, we are ready to start developing and building this detector that has the potential to detect axions,’ says Jón Gudmundsson, senior researcher in Stockholm and current spokesperson for the ALPHA collaboration.”
The overall collaboration involves eleven institutions, in addition to Stockholm University, including the universities of Berkeley, Yale, Colorado, MIT, Johns Hopkins, Wellesley, Arizona State, ITMO, Cambridge and Oak Ridge National Laboratory.

Contribution to the analysis of axions

Postdoctor Andrea Gallo is a researcher in astroparticle physics at Fysikum, Stockholm University.
“I was born in Turin, Italy, and in 2019 I got my PhD at the Gran Sasso Science Institute (GSSI) in L’Aquila, a city quite close to Rome”, says Andrea.
His PhD verted on the analysis of supernova neutrinos, which he continued immediately after with a Postdoc at Laurentian University (ON, Canada). In March 2021 he came to Stockholm and Fysikum. He's now working in the ALPHA experiment, on a project contributing to the simulation and analysis of axion experiments.
“The experiment is currently under construction at Yale university. We’ll hopefully be able to read data in the following years. The idea is to use a strong magnetic field to transform axions into photons; that is, radio waves. This is a godsend for experimental physicists. However, the identification of the signal might be challenging. That’s where our analysis tools may come in handy”.

Axions are fuelling progress that no gost will ever take away

“The task is challenging but the technology is promising. Its development is the result of the collaboration among solid-state physicists, electrical engineers, particle physicists and even mathematicians. Despite being hypothetical, axions are driving a progress that is very real.” says Postdoc Andrea Gallo Rosso.

More information

Contact Andrea Gallo Rosso

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