baptismal celebration called First Collision. In fact, in the life of a particle collider, the most exciting moment is when physicists observe the first collisions.
So it was quite natural and nearly compulsory that I volunteered when the alumni were asked to help with the CERN Open Days 2019.
After I had assured may stay I took the train from Freiburg to Geneva. When I stepped on to streetcar number 18, I became already excited because all trams and busses flew flags of CERN and of the Open Days.
|The following morning at my hostel. View of the Alps and Mont Blanc|
|The LHC is shut down until 2021 for an upgrade to reach its final energy of 14 TeV|
|LHC superconducting magnet string underground.|
You barely see the curvature of the ring tunnel.
Then I started exploring my former place of work.
|A development I lived through. I frequently had coffee with Robert Cailliau.|
|I only knew that Werner Heisenberg was a table tennis champion.|
|A special coffee only found in the Geneva region, the renversé|
|In the evening: a reception for the alumni helping with the Open Days|
at the tennis club "Le Smash". Note the white cylinder hanging from the wall:
An RP radiation monitor (see text below)
|The Saturday morning Radiation Protection crew waiting for visitors. |
In front right: one of the radiation measuring instruments on display (©RP CERN).
|While we were waiting at our stand at 9:18 a.m. for our first customers|
there was already a waiting time of two hours to visit the ATLAS experimental area.
*Sievert (Sv) is the SI-unit when measuring radiation. This is a big unit, so in radiation protection doses are expressed in mSv, μSv or even nSv
|Bananas are good for your health|
Being on a plane from Europe to the States exposes the occasional passenger to a dose of 50 μSv due to cosmic rays. Doses to flying staff accumulate, so pilots and cabin crews are in the category of professionally exposed workers. While at CERN people working in radioactive areas or with radiation sources wear dosemeters to determine their personal radiation doses, doses to flying staff are evaluated by calculation. In fact, exposures to cosmic rays are well known for the routes planes take routinely.
|Lying in the sand|
|On the evening of the first Open Day|
All these demonstrations were very popular with our visitors and in most cases extremely useful to dissipate their underlying angst.
|The Sunday afternoon crew (©RP CERN)|
At the end of those highly successful Open Days at CERN, I was tired, but a the same time satisfied having helped my former colleagues selling our trade to the visiting public.
|Drinking my well-deserved craft beer |
in the evening sun at the terrasse of the CERN restaurant.
|Full moon: Goodnight and goodbye CERN|