This week I took a brief trip to Fermilab to attend a little bit of a workshop on upgrades to the CMS detector. Now yes, this is nutty on its face — what are we doing talking about upgrading a detector that has yet to see its first collisions? How can you know what needs upgrading? Unfortunately, the time scales for completing such projects are very long, and we need to start planning now. By 2013 there are supposed to be LHC upgrades to improve the beam focusing at the collision points, and CMS will want to make changes to make the most of this. That’s only five years away, and given how long it can take to do the R&D work and then actual construction of the detectors, you have to start now.
It definitely would be better to have some real data, and certainly what we learn from collisions as soon as we have them will inform what we do in the upgrade. However, we already have plenty of information to chew on. We learned a lot in the course of the construction of the detectors, and know that there are specific problems we would like to fix. The current detector was already designed some years ago, and there have been technical advances that we would like to take advantage of. (I was struck by one talk about electronics in which it was stated that there is an increased focus on making components with low power consumption; this is an issue on the computing side too.) And perhaps in the course of the upgrade studies, we’ll learn something that will allow us to operate the current detector and analyze its data in a more clever way.
Due to my own schedule constraints, I could only stay for a day of the workshop, and thus I won’t claim that I did any real work! However, it sounds like some progress was made. We expect that we’ll have to rearrange our tracking system, and as part of it we want to be able to have an online track trigger, something we don’t have right now. That is a very difficult technical problem, but people agreed on a strawman layout for the tracker that people could at least use for studies, and a general strategy for how the triggering could work.
I am slightly embarrassed to admit that this was my first visit to Fermilab in about six months! The new baby here at home has kept me from traveling around as much as I ought to. So there were lots of people to see and say hello to (including the guy in the badge office; my ID had expired and got confiscated at the gate!). There never is enough time in the day at the lab to talk to everyone I want to see. I’m looking forward to getting back again soon(ish).
