Blogging the LHC startup - personal perspective

Hi, all,

Just decided to blog my experiences on this putatively historic day.

Last night I was "on-call" for the Prompt Feedback Group (PFG) for my subdetector HCAL (hadron calorimeter) of the CMS detector.

~3:30 a.m. - sacked out on the couch after tweaking my software a bit more.

~4:15 a.m. - got a call from FS that "some action expected" between 5-6 a.m. (there were rumblings of possible "accidental collisions" before the main event). I went back to sleep.

~6:45 a.m. - woke up to G. yelling in her bedroom

~7:00 a.m. - checked my email, but no action yet.

~9:05 a.m. - dropped off by K. and the kids at Building 8, which is close to the CMS Centre, where all the muckety-mucks and press are gathered (along with the other control rooms of the other experiments and the LHC control room in Prevessin, France). Told K. that we are within ~10 minutes of making history.

~9:06 a.m. - Was greeted by a swarm of people coming out of the CMS Centre, including FS and EY who told me that the LHC is down (cryo problem I was told, although LHC Page 1 only says "beams dumped"). No beam for a few hours! I'm in an office with J. who's a Tevatron veteran and says this is perfectly normal for a startup.



~9:36 a.m. - Shift ELOG says "[magnet] quench in A18R1", no beam for 3-4 hours.

~9:40 a.m. - new comment on Page 1 says they are recovering sectors 1-2 and 8-1. (LHC has eight "points" 1-8 and the sectors are referred to by their endpoints - "1-2", "2-3", "3-4", etc. up to "8-1". Point 1 is where ATLAS is located and Point 5 is where CMS is located.)

~10:23 a.m. - new comment on Page 1 posted 10:19 says "BEAM EXPECTED IN 1 HOUR" - that was fast!

~11:13 a.m. - I notice that the Shift ELOG relays more information from the LHC control room ("QPS" is the LHC's Quench Protection System):

Between 8.49 and 8.55, strong noise induced to the LHC
(probably from the network), frequency ~0.1 HZ.
QPS (some signals shwon in attachment) triggered
in sector 81 (8.49:48) and 12 (8.51:17). In sec 12
the nQPS board on B19R1 (known to be problematic)
fired the heaters....Source of noise should be
tracked to the trip of one of the 2 families of
SPS quads. The one staying on induced the noise
on the surrounding facilities, LHC included. The
frequency matches the SPS cycle

Preparing now for injection of beam.

~11:52 a.m. - "Ramping again" - this is when the ramp up the bending magnet currents and accelerate the particles to match, until they get to "Flat Top" at the desired energy.

~1:00 p.m. - Beams are aligned, COLLISIONS! ...and there was much rejoicing.

~1:22 p.m. - Stable beams declared (heavy absorbing blocks are placed close to the beam line near each experiment to protect the experiment from the beam straying and to clean up some of the garbage flying along with the beam). This means the experiments (like CMS) can turn on the more sensitive parts of the detector that are close to the beamline and could otherwise be damaged. Joy and mirth all around!

~2:15 p.m. - Still struggling to get my analysis to work when I get a call from PB. Apparently they want to do the "HF scan" that we had hoped to do with lower energy collisions for all of the last two weeks. With the media event still going on! Frankly a little shocked, but it means I have to drive up to Point 5 and jump into the fire.

2:15-3:00 - Frantically make arrangements to get a vehicle and get my cell phone charger, make my way to Point 5. PB tells me that they're already starting the scan, get there ASAP.

~3:00 p.m. - On the way to Point 5, I got pulled over by the French police! - within sight of the surface hall, even. Why? ...wait for it....for talking on my cell phone when I was driving! Whattaya mean? It's LHC Startup Day! First Physics, haven't you heard? Of course I'd be on the phone while driving. Psha! Given the way I was driving I was glad that was *all* I was being pulled over for - and I had just picked up the vehicle I was driving from the CERN shop just 20 minutes before. I called PB to tell them what was happening, so when I arrived at the surface control room I got a ribbing. Hopefully no media will try to take a statement from me...btw, the fee was 22 euro and two "points" docked from my driver's license. JS said they'd take up a collection for me ;) The policeman was professional enough and spoke enough English to make the transaction efficient at least.

~4:32 p.m. - still in the middle of the scan, should take a total of 4 hours.
~4:32 p.m. - spoke too soon: "emergency dumps...end of the first physics fill...preparing for ramp down." No beam for 2-3 hours, go home, have dinner, come back to pick up where we left off...

~6:15 p.m. - driving home I have to kick myself: I should've asked the gendarme if I could get his photograph! "You wouldn't mind if I posted it on the internet, would you? Don't smile, now..."

~7:30 p.m. - Beam back by 8:30, ramping takes ~1 hour, so cooling my heels at home until then, seeing if I can beat my analysis software into submission.

~9:50 p.m. - Page 1 now says "Trip of RQT12.R4B1...access needed ~2 hours". I'm starting to wonder if we're going to be able to finish the scan.

Addendum: Overall a day of huge milestones. We are "well and truly" kicked off on our physics program. At home, the kids are also surprising and even astonishing us. Just today K says that G has been walking all around the house - carefully. And when I got home for supper, B did several things none of us have ever seen him do. He picked up a soccer ball and then "tossed" it down as if to bounce it, and continued to pursue the ball around the apartment. He kicked it a few times by walking into it, and even crawled under G's crib to poke the ball out when it rolled underneath. He's problem solving, and he's involving people in his play. K attributes it at least in part to this miracle supplement "Enhansa" - googling it will give you many anecdotes praising its merits. His rapid improvement are also taking his therapists by surprise as well.

Check out these two videos...

Photo Sharing - Video Sharing - Photo Printing

Photo Sharing - Video Sharing - Photo Printing

But the day ends as it began, with G screaming and yelling from her bedroom. She's not having a good night tonight. Both her and I seem to have come down with cold symptoms.

Keep it real,
-PKBGD