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CERN scientists Archana Sharma and Pieter Mattelaer round off the investigations in response to the primary schools’ challenge

At a considerable advantage thanks to the previous teams’ findings, will Archana and Pieter finally work out what’s in the boxes?

Monday, 04 April 2022


Archana and Pieter analyse X-rays of the boxes to try to work out what’s inside (credit: CERN)

Following several months of investigations, Archana Sharma, an experimental physicist, and Pieter Mattelaer, a civil engineer, were the fifth and final pair to examine the boxes.

In June 2021, to mark the 10th anniversary of the Be a Scientist project, pupils from Jean de la Fontaine school (Prévessin-Moëns, France) and Cérésole school (Petit-Lancy, Switzerland) set a challenge for CERN's scientists. Their task? To find out what was inside two boxes without opening them!

For ten years now, schools in Geneva, the Pays de Gex and Haute-Savoie have been receiving mystery boxes from CERN. The pupils, aged between 8 and 12, produce hypotheses, collect data and use factual information to determine the boxes’ contents. This year, the roles were reversed.

On the advice of Dorota Grabowska and Alberto Di Meglio, the previous team to take up the investigation, the boxes were X-rayed. In the hall of CERN’s Building 40, Archana and Pieter were thus able to round off the investigation with a significant advantage. Thanks to these helpful images, the duo made numerous discoveries, validating some of their predecessors’ hypotheses. Which of the previous four pairs was right? Is there a metal detector in the French box, or a little bell in the Swiss one?
Watch this space – the boxes will be opened and the contents revealed in the next and final episode of the Schools Challenge!

Visit voisins.cern for regular updates on the challenge and to follow the progress of the investigation by the CERN community.

X-ray of the Swiss box
X-ray of the Swiss box designed by the pupils of Cérésole school in Petit-Lancy (credit: CERN)


X-ray of the French box
X-ray of the French box designed by the pupils of Jean de la Fontaine school in Prévessin-Moëns (credit: CERN)