Samstag, 19. Juli 2014

Something else

Well I wrote somewhere, that I try to describe what I do beside working on my master thesis. So far that wasn't really a problem, but as you might guess from this introduction, it wasn't the case for the last couple weeks. So now you don't get around some electronics and physics.
Maybe I should start about what my work is actually: I'm working on this. The ATLAS has been running together with the other experiments at CERN. An upgrade is in development and if everything works out it might be installed in around 8 to 10 years and my work helps in one alternative part of the trigger system. The trigger is used to decide, which events have to be stored or which can be discarded. More precisely I've been developing a logic, dedicated to detect correlations of high momentum particles in a very fast way. The long version can be found here.
In order to test all the setup it was possible to get a slot of test beam at SLAC. The date was fixed 1. to 15. of July and so we had to finish the doublet. It is a silicon strip sensor and has a ASIC chip to read the signals from the strips. The very thigh schedule, where all the steps were planned and which meant to glue things at 8pm or later, actually worked out and the doublet was running on the 4th of July. So we started the long weekend in the Lab. One upside, you have a nice view over the whole bay and we could watch fireworks from all over the place.
After testing more as good as we could, we moved the whole setup on the 5th to SLAC and installed it in end station A.
After installing everything we made our self at home in the counting room above the ESA. There were like 6 flights of stairs to go up. I don't know how many instruments and electronic cards were in this room, but it was a lot. Most of them were switched off, but still many were running, without anybody checking them. It wasn't really clear if they all these instruments were actually remotely controlled, or just running and nobody dared to switch them off. It might be that they still have a purpose nobody knows about.
On the first day, we didn't really see anything. The setup was installed and working, just no real results yet. Coming back on Sunday, we let the beam run again and this time we saw something with both of our experiments. After fiddling around with the configurations of my setup, I got correlations and they were plotted on real time on the data acquisition system I developed during the past few months. It's not a very sophisticated system and there I made several improvements during the beam time, but it worked and everybody was quite thrilled to see the correlations show up the screen.

It took still some time to completely understand the data read back and get a good feeling for the whole setup. We had also to adjust the mechanical part of the doublet, but at the end it worked and in a final night session we got all the measurements we wanted to do. It meant to go down to ESA every 20 min for between something like 1am to 5am. And each time you have to call main control to get access to the end station. At the beginning it was like: (me, MCC) "Hi MCC, this is Niklaus. We're two people to get in to ESA." "Ok. What are the names?" "It's me, Niklaus and Amar." "Ok, here are you're keys." "Thanks, got them." "And here is the door." "Thanks, bye" And the same to get out.
At the end of the night is was more like: ""The two of you want to get in?" "Yes" "Keys ... and door." "Thanks, bye"
Was a fun night :-)
And now I let you wonder at some preliminary results:

So that's what I do here besides chilling around, surfing or exploring California. Last but not least, even at work the group picture can't be missing: