444 adults and children guided through reactor

Probably the biggest open door on the Garching campus on October 3 was the one at the FRM II for the guided tours for adults. © FRM II / TUM

For 364 adults and 80 children, probably the largest door on the Garching campus opened on October 3: they entered the FRM II research reactor through a gate in the fence. Hundreds of others were busy at the hands-on stations of the MLZ and FRM II in the physics building of the Technical University of Munich.

Ice cream as a surprise
Most of the children who managed to get one of the coveted Mouse Day tours of the Heinz Maier-Leibnitz Research Neutron Source now know that there is an ice-cold surprise at the end of the children’s tour of the FRM II during experiments with liquid nitrogen. Which type of ice cream it will be in the end, however, still remains a real surprise.

The visit to the reactor operators in the control room was one of the highlights of the children's tours as part of the “Sendung mit der Maus” door-opening day. © FRM II / TUM

Guided tours fully booked for weeks
The staff of the FRM II and MLZ offered a total of 24 guided tours for adults, four of which were in English. 7 to 13-year-olds were able to take a look at the reactor pool and the neutron guide hall west as part of the door-opening day of the “Sendung mit der Maus” show with the three tours “Mouse”, “Elephant” and “Duck”, as well as visit the reactor operators in the control room. The guided tours, which could be booked online in advance, had already been fully booked for weeks. On the Day of German Unity, the FRM II and the entire Garching campus opened their doors to interested visitors.

Visitors followed the tracks of cosmic particles in the cloud chamber. © FRM II / TUM

Observing traces of particles
In addition to the guided tours, there were also stands and hands-on stations from the Research Neutron Source and the Heinz Maier-Leibnitz Zentrum (MLZ) in the physics building. Visitors were able to measure the natural radiation of bananas and Brazil nuts with FRM II radiation protection measuring instruments, view a fuel element dummy and observe the traces of passing particles in the cloud chamber.

Antimatter and throwing games
Few people know that the antiparticles of electrons, positrons, are also used for research at the MLZ. The positron group explained to visitors at their stand how antimatter is produced from neutrons in the research reactor. At the MLZ stand, visitors could marvel at the computer-controlled Lego model of a three-axis spectrometer and a model of a radiography system. Current job advertisements for the FRM II attracted potential applicants. There were also two throwing games with “neutron” balls and a painting and craft table for children.

An audience of around 50 listened to the lecture by Dr. Michael Schulz on the subject of “Ice-cold illumination”. © FRM II / TUM

Presentations on research with neutrons
The MLZ also took part in the lecture series of the TUM School for Natural Sciences in Mechanical Engineering. Dr. Michael Schulz, Deputy Scientific Director at the FRM II, and Dr. Sebastian Busch, Head of Department at the Helmholtz-Zentrum Hereon at the MLZ, gave lectures entitled “Eiskalt durchleuchtet” and “Klein aber H2O”.

One of the best things about the children's tour: the experiments with liquid nitrogen and the ice cream. © FRM II / TUM

The best: “The reactor drivers and the ice”
In the end, not only the children were overjoyed with the strawberry, chocolate, banana and stracciatella ice cream flavors, but also the adults, who were able to snag free seats at the last minute despite the tours being fully booked in advance. “It was all great,” says 9-year-old Sarah after the elephant tour. “Especially the reactor drivers and the ice cream.”