27 July 2010

The ICHEP meeting was held in Paris from 22-28 July. 

It was a whole new ballgame at the International Conference of High Energy Physics (ICHEP) this year. From the excitement of new Higgs limits from the Tetravon, to the introduction of Monday's plenary session by French President Nicolas Sarkozy, the conference was obviously very exciting. The conference began as the HEP community waited eagerly to hear what had been accomplished with the brand new LHC data so far. The four LHC experiments showed their results in plenary talks given on Monday by their spokespersons. And Fabiola Gianotti did a great job for ATLAS!

Countless people from ATLAS worked around the clock recording, processing and checking the latest data to get everything ready for presentation. The fact that 228 nb-1 of the total 338 nb-1 of data was collected in the last full week before the conference surely made the job a Herculean effort. Results were flung onto graphs at breakneck speeds, papers were flying around and presenters were stressed to the limit. A new era of high energy physics had been born and ATLAS was, in part, responsible for presenting it to the world.

Of the 1000+ attendees, many just wanted to witness who the ultimate winner of this “World Cup” for particle physics would be. In all, there were 196 parallel sessions, 28 invited speakers and 28 poster sessions. (See the list of all ATLAS presentations and posters.) With so much going on, let's take a look at how some of the ATLAS speakers felt ahead of time, the feedback they got and the overall conference atmosphere.

Expectations were high for Fabrizio Salvatore, who presented the ATLAS results on searches for exotic long-lived particles using early data. Fab rightly expected that ICHEP would be extremely exciting this year. Stemming from the novelty of the LHC results, he said that he was, “… sure the atmosphere [would] be thrilling.” Fab was most looking forward to seeing the physics results, to experiencing the atmosphere at the conference, and, though nervous, he was very much looking forward to presenting this paper.

Jan Kretzschmar, who gave one of the two ATLAS W and Z cross-section measurement talks, looked forward to meeting old and new colleagues, as well as getting to see the CMS results. Last week, Jan commented on the intensity of preparation saying, “The W [and] Z results are constantly being updated as the new data comes in. ” There was little time yet to do in-depth analysis. This sentiment was echoed by many as a result of the fortunate, yet last-minute data increase.

Fab felt an intense mix of nervousness and exhilaration when anticipating his presentation. He said, “Presenting the results of the experiment one is working on is one of the most rewarding experiences for a physicist and, clearly, being able to present for ATLAS at ICHEP is one of the highest points of my career.”

The paper came from the SUSY group about whom Fab spoke very highly. “This is clearly one of the best parts of working in the field of particle physics: people from different countries, and very different cultures, work together toward the same result.” He emphasized how helpful everyone had been with result preparation and feedback about his presentation until the final hour before he presented.

Both Jan and Fab said they felt confident with their performances. Although they were both nervous, each got positive feedback from the HEP community. Jan noted how packed the room was where he spoke and said that many people were interested in the first results from ATLAS and CMS. According to Jan, several of the most frequent questions were related to the, “… level of data-MC understanding we have achieved so far.”

Rick Van Kooten, who was presenting a recent result from the D0 experiment, commented on how ATLAS and CMS compared. “Regarding performance and ‘being ready for data’, CMS and ATLAS really are running neck-to-neck and are quite similar. There are a lot of exciting first results, and the level of understanding of the detectors is very impressive. This is true for jets, E_T, missing E_T, lepton ID, b-tagging, etc.”

Fab perceived a general understanding that data collected so far was not enough for any of the experiments to show discoveries of new physics beyond the Standard Model. This limitation didn't seem to matter though because a, “…first look at the LHC data was enough to get people intrigued...”

Fab cautioned that, “As time goes on there will be more and more expectations of new results from the LHC experiment, so pressure will build up.” In order for a presenter not to feel overwhelmed by pressure, he said they should keep in mind the extensive help they have available. He found the review process by experts, conveners of his group and ATLAS collaboration to be very thorough. Consequently, his advice was that a presenter should guard against excessive worry by accessing their ample support system. But whatever you do, Fab says above all, remember to simply “Enjoy it!”

For those interested, all ATLAS results presented at ICHEP are available here.

Sarah McGovern

ATLAS e-News