2010: The year that was…

15 December 2010

 



2010 was an eventful year for ATLAS. Just one week after registering the highest energy proton-proton collisions, ATLAS saw its first W boson candidate, and so began the rediscovery of Standard Model physics, and even some potential new physics…

The excitement this year kicked off in the Control Room, the physical focus of everyone's expectations for the promised 7 TeV collisions. Jim Degenhardt was in there just before the world record was smashed:

If you ask me what the most memorable thing that happened this year was, well I think that would almost be a no-brainer: March 30th, 2010: M-Day – 'M' is for media – a.k.a. the day the LHC started colliding at 7 TeV centre-of-mass energy. I was shift leader the day before … everyone was trying to make sure their sub-system would not break 'THE' run."



Andrej Gorisek, was Shift Leader when the fabled 7 TeV collisions finally arrived:

It felt quite un-real. The ATLAS control room was full of people. It was almost impossible to move around and to have proper communication between the shift leader and other shifters. Only a few minutes before first collisions and only a few moments before the energy reached 3.5 TeV, I had to ask the run control shifter to start the trigger, which was then still a manual operation. On a normal day that would be trivial, but on March 30th, it was a challenge to come through the crowd to his desk. When we started seeing collisions, one could feel that in that very moment everybody was excited and proud of being a member of the ATLAS Collaboration.



March 30th was just the start of eight months of Control Room high-points, according to Operations Manager Daniel Dobos:

The 2010 data-taking in the Control Room was really fun. Reaching many times new records for bunch intensity, instantaneous and delivered luminosity, after long nights or weekends with very stable – which isn't to say boring – operation were amazing. On the other hand, it was thrilling to see how efficiently ATLAS woke up immediately, day or night, from this stability mode every time something unexpected happened. Everybody worked hand-in-hand to record as much as possible of the collisions our wonderful LHC colleagues provided us with.



Speaking of recording as much data as possible, the TRT stole the show this year with an unbroken 100 per cent data-taking efficiency record. Although there were one or two nail-biting moments, says TRT DAQ expert, Jonathan Stahlman:

The TRT maintained 100 per cent data taking efficiency in 2010 despite some close calls. One time, we worked until 2:00 a.m. fixing bugs before the upcoming physics run, only to have a hardware failure early the next morning. We swapped the board, just in time for the LHC beam dump anyway!



In their little camp above the Control Room, Markus Elsing's event display team also delivered under pressure, again and again:

What started in 2009 as an activity for the start of LHC collisions, turned into a regular event scanning activity in 2010. It was fun to see that we were able to produce in quick succession nice displays of first 7 TeV collisions, first high-pT jets, W and Z decays and top events seen in ATLAS. And at the end of the run the Heavy Ion events with asymmetric jets got us all excited. Let's see what 2011 will bring us in terms of the next interesting events!



The Trigger, too, was at the top of its game, picking out interesting events for the collaboration to pore over, reports Trigger Coordinator Srini Rajagopalan:

What happened in 2010? Five orders [of magnitude] of luminosity rise, seven-fold in energy, the democrats lost the [US] house, the glaciers melted away, Spain tore through the football ranks... but one thing remained steady through all these nail biting events: With 95 per cent data taking efficiency, the trigger delivered, thanks to a stupendous and tireless effort of a team that only brings disbelief. Their dedication has set ATLAS on a road to success. Bring on 2011!



Spoilt for choice of exciting moments in 2010, Data Preparation Coordinator Beate Heinemann picks out the data preparation effort in the run-up to ICHEP as the single most challenging time and important achievement:

Here we went into an 'accelerated' mode where we asked the systems to be even faster in their calibration in order to process the data quickly, and to get the data quality and luminosity information very promptly, so that high quality data with the full statistics could be shown. This was accomplished and as a result it was possible to show on the Friday at ICHEP in Paris the first search that probed new physics beyond the Tevatron, using the full luminosity acquired up to the Monday before. This was only possible due to the extraordinary dedication of the many experts on all the related data preparation subgroups and from the detector subsystems.



It was worth the effort, of course. Jon Butterworth, Standard Model Working Group co-convenor, was there:

Sitting in the audience and finally seeing Fabiola show data we had 'now', rather than talk about what we're expecting 'soon', hit me more than I expected. It was a weird kind of calm, satisfied excitement.



Physics Coordinator Aleandro Nisati, says that this is just a taste of what's to come:

The first year of LHC physics with ATLAS was amazing, next year's run will be even more exciting!



The first paper to come out of ATLAS was the minimum bias paper, at the end of March. Heather Gray worked on the analysis:

It was a privilege to be part of the first ATLAS paper. It was very exciting and intense with everyone working unbelievably hard. I don't think I'll ever forget the Saturday night meeting that lasted almost until midnight. The whole thing was probably the most intense experience of my career.



And hot on the heels of the first proton-proton paper in the spring, the excitement was to be repeated all over again with the first heavy ion paper in November, ending the year on a high note for ATLAS. David Miller, one of the students drafted in at short notice to work on the data, met up with other co-workers in a trans-Atlantic EVO chatroom:

As the urgency of the heavy ion analysis became clear, different members of the management contacted a few graduate students, located around the world. We immediately pooled our resources, and divided up the tasks to help verify the ATLAS answer to what may be the most important LHC physics question to date: Have we observed jet quenching in a quark-gluon plasma?



The heavy ion run brought out the best in the collaboration, says Run Coordinator Benedetto Gorini, who watched people rally together in the face of the new challenges:

What really impressed me was how the Heavy Ion people managed to build enthusiasm around them. I was quite worried because most of our online experts were coming from an exceptionally demanding data-taking period and I was afraid of a serious decrease of the level of attention. But the Heavy Ion people adopted a very didactical approach, with short physics-oriented presentations appended to most daily run meetings. In a short time we were back to levels of enthusiasm that reminded me of the first proton-proton days, just with a little less crowded control room…



Others had their own unique methods of drawing out the collaborative spirit. Cue Christian Ohm standing on a bar and singing a duet with Paul (Jack) Jackson for a large fraction of the collaboration during the Copenhagen ATLAS Week. Certainly a highlight for anyone who witnessed it, and there were plenty who did... For Christian though, there are headier heights:

My favorite moment of 2010 was not when me and Jack got wasted and sang [...] at a karaoke bar in front of all the important grown-ups at the ATLAS Week in Copenhagen, but when they wrote about it in the ATLAS e-News.



Joking aside, Copenhagen was also the venue for the collaboration growing and officially welcoming South Africa as a Collaboration Institution. Trevor Vickey remembers the moment when he found out:

Simon Connell and I nervously waited outside of the Collaboration Board meeting with bottles of wine in-hand (to present as gifts if the vote was successful, or to drink ourselves if it had failed!) As soon as I heard the distinctive droning sound of the vuvuzelas, I knew that we had done it.



As well as new collaborators, ATLAS also welcomed back old friends, like Martina Hurwitz who had to decamp to Fermilab for a short time to finish her PhD.

I left ATLAS before any collisions were recorded, and returned in the course of this year's run. It is very satisfying to see friends and colleagues who were instrumental in getting the detector working now successfully analysing data and producing exciting physics results.



As we pause for breath, and ready ourselves for next year's challenges, Spokesperson Fabiola Gianotti places collaboration firmly at the centre of 2010's achievements:

2010 has been a very intense and rewarding year for ATLAS. All the experiment's components worked remarkably well, from the high-data taking efficiency, to the excellent performance of the detector and trigger, and the effective and robust data processing and distribution. We have produced 15 physics papers covering a broad spectrum of topics. Our successes are thanks to the dedication of many people working hard at every stage of the chain. Besides these scientific achievements, we should also be very proud of the collaborative spirit displayed by everyone involved, without which this year would not have been possible.



All that's left to do is to wish fun times and festivities to all readers of ATLAS e-News. Rest up, collaborators. Come back fresh in 2011!


   

 

 

Ceri Perkins

ATLAS e-News