Jan 27 – 28, 2014
LPC, Fermilab
US/Central timezone


Summary of the Workshop

In the middle of LHC Long Shutdown 1, on January 27 and 28, 2014 at the Fermilab LPC, we had a workshop with the title "LPC Workshop: JetMET at High Pile-up, Preparation for LHC Run II." Despite the cold weather where the temperature reached below -25 degrees C, most of the registrants, about 50 people, arrived on time. In addition, more than 20 people attended through a video conferencing system.

On the first day, the workshop was open, i.e., non-CMS members were invited to attend. ATLAS members and theorists, as well as CMS members, gave presentations and joined the discussion. We reviewed physics goals of LHC Run-II, recent JetMET results from ATLAS and CMS, recent theoretical development of jet substructure, and MET performance in high pile-up events. Then, we discussed how to approach the challenges that we face in JetMET reconstruction at the LHC Run-II and after.

The second day was limited to CMS members and was somewhat more informal than the first day. We discussed many specific topics of JetMET reconstruction in detail. The topics discussed ranged from advanced algorithms of JetMET reconstruction and corrections to their software implementations in CMSSW, from particular usages of JetMET objects in various physics analysis groups to prospect for specific future runs and upgrades, such as LHC Run-II, HL-LHC, and CMS Phase-I and Phase-II upgrades. The discussion continued until past 8 PM.

In the morning of the day after the workshop, conveners of the CMS JetMET group had a meeting for a few hours. We summed up the workshop and discussed plans. The plans cover a wide range of the essential topics relevant to JetMET objects, including particle-flow algorithm, triggers, detector upgrades as well as JetMET reconstruction, resolution, corrections. The plans also include the development of common data format and software tools. In addition, we made plans for publications, i.e., three journal publications, several physics analysis summaries (PAS) and a few detector performance notes (DP). Furthermore, we tentatively schedule to have the next JetMET workshop in September in a different place in the world.

We started the preparation for this workshop in August 2013. The workshop ended quite successfully. Many active members of the CMS JetMET group including nearly all conveners of the JetMET group and its subgroups attended the workshop. The discussion was lively and productive. As a result, this workshop set a clear direction in which we should pursue in the rest of the year 2014 in the preparation for LHC Run II and beyond.

February 5, 2014

The Organizing Committee