The XENON collaboration: zooming in on dark matter

Boris Bauermeister and Iulia Popescu on XENON’s mission to decipher the dark matter enigma and how EGI contributes

The XENON research collaboration is made of over 150 scientists in 27 institutes in Europe, US and Japan, working on an experiment aiming to detect dark matter particles in the universe.

Our most recent experiment is the XENON1T detector located within the largest underground research facility in the world – the INFN Gran Sasso National Laboratory (LNGS) in Italy. Xenon1T is a 3500kg liquid xenon detector in search of unravelling the mystery behind dark matter.

What is dark matter?

Dark matter is a form of matter that we scientists believe to account for approximately 26% of the universe. While the Earth, sun and galaxies are visible elements in our universe, dark matter doesn’t reflect or absorb light at all, which makes it invisible. We haven’t observed it directly yet but we are confident it exists for many reasons, for example the gravitational effects it seems to have on galaxies that cannot be explained otherwise. So we believe that dark matter is out there, but what it is made of is still something very much shrouded in mystery.

The XENON experiment – the force that challenges the dark side

With the XENON experiment we are trying to go deep into the search for dark matter. The XENON1T detector aims to detect dark matter particles in the form of weakly interacting massive particles (WIMPs) by looking for their interactions with xenon atoms. The idea is that XENON1T will detect a signal produced by the interactions of dark matter particles with the xenon nucleus.

Former detectors (e.g. XENON100) were based on the same detector concept but were much smaller in size and had less readout channels. A lot of computational challenges came up between XENON100 and XENON1T and we have made a big step regarding our computing infrastructure. We’ve had increasing requirements in terms of data processing, storage and analysis – this is where EGI came in very handy.

EGI-XENON collaboration

During the XENON100 period – processing, storing and analysing data was possible at the LNGS laboratory on dedicated machines. XENON100 detector simulations were run on EGI, at the connected institutes NIKHEF (Amsterdam), SURFsara (Amsterdam) and CNAF (Bologna).

With XENON1T we increased the number of channels in the detector which led to larger data sets. To store, access and process these datasets we use EGI together with Open Science Grid (OSG) in the US. We added two more resources of the EGI infrastructure: CCIN2P3 (Lyon) and the Weizmann Institute (Rehovot). The data storage is organised with grid technology which allows us to access our data easily for further processing.

Processed data are later analysed at the Research Computing Center (University of Chicago). Furthermore, we run more sophisticated XENON1T detector simulations on EGI and the connected facilities are large contributors to our total storage volume (at the moment ~4 PB in total).

The future is bright

The next phase of our research is the XENONnT detector, which will have a dark matter target about three times larger than that of XENON1T. Our collaboration with EGI will continue in this project, where computing resources will be paramount for data storage, processing and detector simulations.

The international team behind XENON

The XENON1T Time Projection Chamber

More information:

Boris Bauermeister is Analysis Tools Coordinator of the XENON project.

Iulia Popescu is Communications Officer at the EGI Foundation.

Xenon website