Helmholtz Zentrum Berlin


BESSY • The ideal microscope for space and time

business as (un)usual

authored a year ago:

Follow me please: The Gun

Currently the GunLab enthusiasts, scientists and engineers involved, are heavily busy @GunLab and again and again agreeing on working schedules there, since it´s too narrow there and not much space to move and work. They have to coordinate slots, and these slots allow each of them to work what and when.

Entering it today, I again passed the entrance of the HoBiCaT bunker, as described in the previous post... HoBiCateingang

and heard and saw my colleague working on the lead brick "fortress", making it stronger, providing the radiation shielding of the future diagnostics beam line.


Asking him, "What are you doing, what´s going on today?" he explained me that he is building the "lead fortress" and that nearby currently the transfer system of the photocathode is pumping off the air (and oxygene), to reach the optimal vacuum conditions. I heard it pumping, "sssssrrrrrr...."


Here is a sketch of the entire future bERLinPro accelerator layout. It gives a better overview what I am talking about and I hope you can follow me a little better with this image. On the very left side of the picture I have drawn myself taking the picture, for your orientation, so you can imagine the position from which we are looking onto the accelerator. In front of me you can see the silver Gun Cavity.


Inside this Gun Cavity imagine all this stuff:


Again - for your orientation - I drew the little girl on the very right side, taking the picture, but now the Gun cavity is open in front of her (she stands for me). The cathode transfer chamber is on the very right hand side, with a long horizontal pipe reaching deep into the module until it stops in front of the 1,5 cell cavity, which resembles a big silver bulb.

When I studied (Geology, not Physics) one of the hardest subjects and lessons to follow was crystallography. My Professor used to say, "and now I challenge your spatial imagination" when he talked about crystal orientations. Explaining you this module remembers me of these past times.

I will try to sketch how this whole thing works, when the scientist brings the photocathode in a vacuum suitcase and the transfer system links it to the inner system of the Gun. And what happens then there. But I am not good in drawing. Give me a little time.