The goals of the Phase II Technical Proposal (TP) are to describe the detector conceptual designs; present a plan for completion of necessary R&D; present preliminary production costs as well as an organization plan; and demonstrate the need for a Phase II upgrade using the physics reach and detector longevity. A successful TP must make a strong and coherent case for the upgrade.

The preparations of the TP started in earnest with the content definition during the CMS week in December 2013. On February 6th the TP studies group started activities with a kick-off workshop at CERN. The main goal for the CMS Upgrade week which took place in Karlsruhe at the beginning of April was to downselect the endcap calorimeter upgrade choices. The second TP version - and the first with full content - will be prepared for the CMS week beginning June 23rd. August will be a busy month, with a collaboration wide review. The final approval and the submission to the LHCC is expected for the CMS upgrade week starting September 1st, with a public presentation to take place on September 23rd.

The goal of the workshop at Fermilab in early May was to bridge the time between the CMS upgrade week in April and the CMS week in June, allowing for in-depth discussions and a review of the state of the TP preparations. The 60 registered participants engaged in lively discussions. The Thursday afternoon and Friday morning sessions focused on the readiness of the software and Monte Carlo productions, followed by a review of the physics objects performance. Friday afternoon was then dedicated to L1 trigger upgrade and physics analyses. A group of 33 enjoyed a social dinner with family style Italian food Thursday evening. A workshop agenda with all presentations can be found here: https://indico.cern.ch/event/305314/.

A number of important topics surfaced during the workshop and required dedicated follow-up in the following days and weeks. Some of these issues are: the endcap calorimeter (both Shashlik and HGCAL) software implementation readiness, the photon identification requirements needed further optimization, tracking resolution is estimated using analog readout, contribution of the Muon upgrade components on the trigger performances and a detailed discussion on how to build a trigger menu to make the case for the L1 track trigger and increased bandwidth was needed. Some of these items will be followed in the standard TP studies group meetings while others have been addressed during the Muon mini-workshop or will be addressed in the L1 Trigger Review.

Meanwhile, the Monte Carlo samples that are needed to assess the physics object performance for the Phase I and Phase II detectors are becoming available. Unfortunately, despite the painstaking work by the PPD, offline and computing areas, our computing capacity is currently exceeded. The combination of the productions needed for the upgrade, the preparations for 2015 (CSA14) and some ICHEP-related samples is putting a strain on the overall production capacity. The samples for the Upgrade studies are currently the highest priority to ensure that the results will be available in time for the TP. The studies of these samples will demonstrate the need for the CMS Phase II upgrade and are the input to the Physics analyses showing the reach of CMS’s High Lumi LHC program. The study of the Monte Carlo samples was defined as an important next step following the workshop together with the generation of samples including the new endcap calorimeter options.

The second outcome of the workshop at Fermilab was the definition of the workflow to process parameterized simulation using Delphes. Shortly before the workshop roughly one billion background LHE events were recovered from a production used for the Snowmass studies during the Summer 2013. These samples are the core background samples for physics studies in the TP. A first test Delphes production was planned for May and samples with tuned object performance using the Phase I and Phase II detectors are scheduled for June, pending the validation by the POGs.

A highlight of the workshop was the presentation of the performance of the Phase II tracking detector. The current conclusion is that the detector performance in tracking charge particles with 140 pileup events per crossing, will be similar to that of the Phase I tracker at 50 pileup and that the transverse momentum resolution is improved. Together with longevity studies, which show a quite poor performance of an aged tracker at 140 pileup, a very strong case for the Phase II Tracker Upgrade was presented.

The coming weeks will be crucial for the preparations of the TP. The samples needed are currently trickling in and we are planning a special TP Studies group meeting on June 5th to review the performance of the objects from Full Sim and in Delphes. A large part of the collaboration needs to be involved to make this project a success for CMS.

We would like to thank the local organizers at Fermilab for setting up this workshop directly following a review by the Department of Energy.

by Lucia Silvestris and Markus Klute