ORGANISATION EUROPEENNE POUR LA RECHERCHE NUCLEAIRE CERN EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH

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1 Minutes January 2016 ORGANISATION EUROPEENNE POUR LA RECHERCHE NUCLEAIRE CERN EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH CERN RESEARCH BOARD MINUTES OF THE 214 th MEETING OF THE RESEARCH BOARD HELD ON WEDNESDAY 9 DECEMBER 2015 Present Invited Apologies S. Bertolucci, K. Blaum, F. Bordry, P. Collier, F. Forti, R. Forty (Secretary), J. Garcia Perez, F. Hemmer, R. Heuer (Chair), J.M. Jimenez, W. Lerche, L. Mapelli, E. Meschi, R. Saban, C. Vallee, H. Wilkens E. Elsen, F. Gianotti K. Johnston, L. Miralles, E. Tsesmelis Items 1. Procedure 2. GRADE: Generic pre-r&d at IdeaSquare 3. Report from the LHCC meeting of 2-3 December Report from the SPSC meeting of October Report from the INTC meeting of November Any other business

2 1 PROCEDURE 1.1 R. Heuer opened the meeting, welcoming representatives from the incoming Directorate. This would be the last Research Board meeting of his mandate, and he expressed his thanks for the support of the board. The membership will be updated with the new management team, and outgoing members were thanked for their contributions. 1.2 The minutes of the last meeting [1] were approved without modification. 1.3 There were two matters arising from the minutes: the approval of GRADE, which is discussed below in Item 2, and the ALICE Online-Offline (O2) TDR, that was approved at the last meeting subject to points being addressed concerning the funding, the interface with the CERN departments involved and the WLCG, along with possible noise pollution at Point 2 of the LHC. It was reported that discussions with CERN services have been concluded successfully and no unexpected costs were identified in the project. For the new computing room a commercial Modular Data Centre solution has been identified and noise simulations are being performed to address noise pollution issues at Point 2. The Research Board confirmed the approval of the ALICE O2 TDR, on the understanding that these issues will continue to be closely monitored. 2 GRADE: GENERIC PRE-R&D AT IDEASQUARE 2.1 S. Bertolucci presented [2] the Memorandum of Understanding for GRADE (Generic pre-r&d at IdeaSquare) [3], which had been adjusted following the feedback received at the previous Research Board. It is intended to act as an administrative framework to help in the development of early-stage R&D efforts on new promising detector concepts and technologies, for possible use in future experiments. A strong educational involvement from the IdeaSquare programme is foreseen, which is also intended to explore the potential use of these technologies outside HEP. Specific individual R&D activities will be attached as addenda to the MoU. While they are named as experiments, it was suggested that their organization should be kept light, without need for a spokesperson. Also, for decisions on the selection of proposed activities, and for issues relating to CERN resources, the Director for Research and Computing should be 2

3 involved. The Research Board approved the setting up of the GRADE framework, once these suggested modifications to the MoU have been implemented. 2.2 The first specific activity to be associated to the GRADE framework is SIMPLE (Silicon Photo Multipliers for Generic Detector R&D) [4], concerning R&D on silicon photomultipliers. The goal is to develop solutions to the current issues of size limitation of sensitive area and of the related performance degradation. SIMPLE was approved by the Research Board to participate in the GRADE framework, with reference number GR1. 3 REPORT FROM THE LHCC MEETING OF 2-3 DECEMBER F. Forti reported from the latest meeting of the LHCC [2]. The proton-proton run in 2015 had been successfully completed, with more than 4 fb -1 of data delivered to ATLAS and CMS at 13 TeV collision energy. In addition, 28 pb -1 of proton-proton reference data for the Pb-ion run was delivered at 5 TeV collision energy. The Pb-Pb run was in progress. Various issues had been addressed (such as with the TDI, electron beam cloud, and dust particles), but most of the machine commissioning for the higher energy and 25 ns bunch separation has now been completed, so that 2016 should be a luminosity production year. The experiments have generally been performing well, with high efficiency, but there were some issues that are discussed for the individual experiments in the following paragraphs. The Research Board took note. 3.2 ALICE reported good progress on physics analysis, with six papers published, four papers accepted for publication and 11 papers submitted for publication since the previous LHCC meeting. Among the new results are the measurement of direct photon pt spectrum and the detailed studies of energy loss in the quark-gluon plasma. ALICE had a successful pp run at 13 TeV, and at 5 TeV for reference data for the Pb-ion run. All new ALICE detectors were fully integrated in the experiment and are operating well. The Pb-Pb run at 5.02 TeV/nucleon energy has started well, with the design luminosity of cm -2 s -1 reached and luminosity levelling activated. Some larger than expected space-charge induced distortions in the TPC have been observed during the high rate data taking and are under investigation. 3

4 3.3 ATLAS physics analysis is progressing well, with 488 scientific papers submitted so far, including 17 since the previous LHCC session. ATLAS has been taking data smoothly and with high efficiency, recording about 4 fb -1 of pp collisions at 13 TeV and the heavy-ion run was progressing well with about 0.15 nb -1 of Pb-Pb data collected. The LHCC took note of issues with a rise in current in the Inner B Layer (IBL) read-out electronics, which is correlated with luminosity and has been traced to a known effect in NMOS transistors. The resulting temperature rise causes distortion of the detector geometry but does not affect the functionality of the IBL, and the effect is expected to improve with higher radiation because of compensation. One new large xenon leak was reported for the Transition Radiation Tracker (TRT) and is inaccessible for repair. The detector is currently running on argon for the Pb-Pb collision period, and in 2016 a hybrid running configuration of xenon/argon (or with krypton) will be implemented. The LHCC took note of the bellows distortion in the End-Cap Toroid (ECT) magnet, the origin of which is now understood. A plan is in place for the Year End Technical Stop (YETS) to first provide a temporary precautionary vacuum seal, to inspect the current leads and make any required repairs, and then to encase the distorted bellows with permanent outer bellows to provide the necessary vacuum seal. 3.4 CMS has published or submitted for publication a total of 445 scientific papers. The CMS sub-systems, including detectors, trigger, online and offline reconstruction and analysis are performing well in Run 2. Many improvements having been completed successfully during Long Shutdown 1 (LS1) and the experiment restarted data-taking well. The pp run at 13 TeV has been completed successfully with about 4 fb -1 of data recorded by CMS, about 75% with magnetic field on, and the heavy-ion data-taking was in progress. The operation of the solenoid magnet remains an issue. CMS, together with CERN, has prepared an extensive clean-up and replacement programme of the magnet cooling system cold box during the upcoming YETS. A long-term magnet operation risk analysis review will also be held. 3.5 LHCb physics analysis is progressing well, with 53 scientific papers published or submitted for publication in 2015, bringing the total to 290, and many new analyses are ongoing for the winter conferences. The Run 2 performance of the experiment is excellent, with about 320 pb -1 of pp data recorded at 13 TeV. Several SMOG runs have 4

5 been taken, studying p-ne, p-he and p-ar interactions. The SMOG runs have been used to determine a 1% uncertainty on the luminosity, allowing for the most precise W/Z measurements at the LHC. LHCb has also taken data for the first time in Pb-Pb running mode. A new trigger scheme has been deployed successfully with the Level-0 triggers being written directly to disk, with alignment and calibration constants automatically adjusted online. 3.6 TOTEM presented new and interesting results from recent studies of elastic crosssections, both at low and high four-momentum transfer squared. Good progress was reported on the Vertical Roman Pot Timing Detectors. Collaboration with CMS is progressing on a beam pipe replacement aimed at guaranteeing space for the TOTEM T2 telescope or possible upgrades. The LHCC acknowledges the need to maintain detector coverage in the region occupied by T2, and welcomes the efforts to adapt the design of the new CMS beam pipe to accomplish this goal. Good progress was also reported on the CMS-TOTEM Proton Precision Spectrometer (CT-PPS). The time resolution performance for the Quartic modules timing detectors is, however, below specification. The LHCC endorses the TOTEM plan to install the current detectors and prepare a replacement programme for the Quartic modules based on silicon (from RD50) or diamond (from the TOTEM Vertical Timing Detectors) sensors. For 2016, TOTEM should discuss with the LHC Machine Committee a proposal for running compatible with the achievable machine optics and running time. 3.7 LHCf has completed successfully the calibration of new detectors for the experiment using electron, proton and muon beams at the CERN SPS. The first physics results on the photon energy spectra analysis from the pp run at 13 TeV have been presented. The joint analysis with ATLAS on diffractive physics is progressing well. LHCf intends to submit a Letter of Intent to the next session of the LHCC for data-taking in the p-pb running mode of the LHC. 3.8 WLCG and the experiment computing have had an excellent start to Run 2. Considerable optimisations have been made, yielding physics results in record times. Many new records have also been achieved in terms of data volume, speed and number of jobs. Improvements are being prepared based on new paradigms such a Clouds, streamlined data models and automated procedures. The available resources matched 5

6 the needs for 2015, and extrapolations for 2016 and 2017 are being discussed. The computing requirements for the Phase-1 and Phase-2 upgrades are also being considered. The requirements for HL-LHC will be discussed in the WLCG Technical Forum, and a workshop at the next LHCC session will aim to produce a timeline for the HL-LHC computing activities. R. Heuer commented that HL-LHC had been classified in the European Strategy Forum on Research Infrastructures (ESFRI) roadmap as a landmark infrastructure. 3.9 All TDRs for the Phase-1 upgrades have now been approved, and the experiments are progressing to final engineering design and the implementation phase. Several noncritical delays have been identified, and the LHCC and UCG will continue to monitor progress. In order to help in the review process, the experiments are requested to provide summaries of their Engineering Design Reviews, an updated global schedule taking into account the shift in LS2, a list of milestones to allow easy monitoring of progress, and information on resources At its meeting in October the Resources Review Board (RRB) considered the first step of the approval process for the Phase-2 upgrades of ATLAS and CMS to have been successfully completed. A scale of funding between the full funding and the intermediate scenario seems to meet the performance requirements. The CERN management, supported by the recommendations of the LHCC and the UCG, deemed as realistic the availability of prospective funds contained in the preliminary funding tables submitted by the experiments. The RRB encouraged the experiments to proceed to the next step, optimizing the detector design and preparing the Technical Design Reports, and this was endorsed by the Research Board. Good progress has been made in qualifying a second vendor for silicon sensors. 4 REPORT FROM THE SPSC MEETING OF OCTOBER C. Vallee reported from the latest meeting of the SPSC [2], including annual reviews of DIRAC, NA61, UA9, AWAKE, OSQAR, and CAST, discussed in the following paragraphs. The Research Board took note. 6

7 4.2 DIRAC has published the first observation of long-lived π + π - atoms. Progress has been made in the analysis of data taken between 2007 and 2012, in particular on the observation of K + π - and π + K - atoms with improved statistics, and on the first measurement of the lifetime of long-lived π + π - atoms. The SPSC recommends that the collaboration should complete these analyses with highest priority and that support be provided to the collaboration at an adequate level to reach this goal. 4.3 NA61 has made progress in the analysis of pp, pc, πc, Be-Be, and Ar-Sc data relevant for the physics of strong interaction, neutrino and cosmic ray physics, and the SPSC is looking forward to their publication. The experiment has been regularly suffering from magnet problems, with the latest fault having a major impact on the physics programme. The SPSC hopes that the current fault is repairable, and if so recommends that CERN and the collaboration set up a comprehensive consolidation programme for the magnets, their infrastructure, controls and operation procedures to ensure reliable data taking in the coming years. The committee received with interest a proposal to perform a beam momentum scan with Pb-Pb, including a potential measurement of open charm production [5], and will further review the proposal. 4.4 UA9 has recently demonstrated crystal channelling in the LHC, and the SPSC acknowledges the outstanding effort made by all the teams involved. The committee recommends that suitable SPS beam time in 2016 be allocated within the overall constraints of the accelerator and users schedule. 4.5 AWAKE has made significant progress on all fronts of the development of the key components and corresponding publications. The increased CERN commitment is welcomed, following the cost and schedule review of the project in April The collaboration has adopted a strategy involving a flexible electron injection scheme and the SPSC encourages the collaboration to consolidate this choice by further simulation studies. Clear priorities have been set for the development of the components essential to the demonstration of the self-modulating instability of a long proton bunch (Phase I) and electron acceleration (Phase II) before the long shutdown LS2, and the SPSC recommends adequate first beam operation in 2016 once the Phase I components are installed and operational. The Research Board endorsed this recommendation. 7

8 4.6 OSQAR has obtained new world leading limits in the laboratory on ALP-photon couplings. Information has been provided concerning the recent chameleon search run and the SPSC looks forward to first analysis of the available data prior to evaluating a request for a further run in Discussions have taken place between the OSQAR and ALPS collaborations concerning the possibility of collaboration on the development of resonant cavities for future more sensitive studies of ALP-photon couplings. It was noted that an upgrade of the cryogenic system for OSQAR may eventually be required, but this would be considered along with any request for a future run. 4.7 CAST completed their approved solar axion search programme in The SPSC welcomes their new proposal describing searches for solar chameleons and relic axions for the period [6], extending the physics reach of the experimental setup. The committee supports the physics motivation of the proposed project, and welcomes the broadening of the collaboration with new institutes, notably the Centre for Axion and Precision Physics Research (CAPP), Korea. The SPSC recommends CAST to focus in 2016 on measurements with the InGrid detector and encourages the collaboration to proceed with the R&D with the KWISP detector and cavities in the magnet. The committee expects to receive more details on the physics results achieved with the InGrid detector in 2015, as well as a description of the final setup for the planned run in The SPSC recommends that CERN and the CAST collaboration set up a programme to upgrade the cryogenic control system of the magnet. The Research Board approved the continuation of the CAST programme in 2016, along with a review of any consolidation required for the cryogenic system. 4.8 The SPSC received two new proposals for experiments to participate in the Neutrino Platform at CERN: DUNE-PT and Baby MIND, discussed in the following paragraphs. As they will be respectively the fourth and fifth approved addenda to the MoU for the Neutrino Platform, they will be assigned reference numbers NP4 and NP5. The previously approved participants in this programme are WA104, WA105 and PLAFOND. 4.9 DUNE-PT is a proposal for a full scale single-phase liquid argon TPC beam test at CERN [7], which is intended to validate the full size components of DUNE and to calibrate the detector response with charged beams. The SPSC recognises the 8

9 motivation of the project and, taking into account scheduling constraints, recommends the proposal for approval as a new project in the CERN Neutrino Platform. An engineering detector should be based on state-of-the-art components tested in previous prototypes and similar detectors. In this respect, the committee is concerned with the fact that many components are not yet fully defined, nor validated, and requests a Technical Design Report containing detailed descriptions of all components and their validation within previous detectors. The SPSC recommends to improve the collaboration between all teams involved in liquid argon-based neutrino experiments at Fermilab, including European experts, in order to ensure that the best available solutions are chosen. For an efficient continuation of the project, the committee recommends that the collaboration set up a permanent team resident at CERN and requests a description of the local management and organisation at CERN. The Research Board approved DUNE-PT to participate in the Neutrino Platform programme, subject to the resources required from CERN being clarified; it will have reference number NP Baby MIND is described in a proposal for characterisation of muon spectrometers for use in neutrino beam lines [8]. The SPSC recognises the interest of tagging muon charges and the potential of a magnetised iron detector, as well as its foreseen application in the WAGASCI experiment at J-PARC, Japan. In addition to building and testing a prototype of a Magnetised Iron Neutrino Detector (Baby MIND), the proposal includes the test of a Totally Active Scintillator Detector (TASD) in an external magnetic field. The SPSC recommends that the collaboration focuses on the Baby MIND part of the proposed programme, and recommends for approval the construction and test of Baby MIND as a participant in the Neutrino Platform at CERN. The H8 beam line proposed is not optimal for low-energy particles and the committee requests that the implementation of the beam test is revised using an existing low-energy optimised beam line at CERN, e.g. at the PS. The committee also requests a common schedule of the Baby MIND and WAGASCI projects, including details on the production of the detector modules for WAGASCI. The proposed tests of TASD in a magnet will be further reviewed once the Baby MIND project is well defined. The Research Board approved Baby MIND to participate in the Neutrino Platform 9

10 programme, subject to the resources required from CERN being clarified; it will have reference number NP P348, a proposed electron beam dump experiment, has had a successful test run. The granting of further beam time will require the submission and approval of an addendum to the proposal. 5 REPORT FROM THE INTC MEETING OF NOVEMBER K. Blaum reported from the latest meeting of the INTC [2]. In spite of technical problems encountered throughout the year, 2015 was still broadly successful for physics. There was low-energy physics until early October, followed by the commissioning of experiments on the new HIE-ISOLDE beamline. 471 low energy shifts were requested, of which 373 were scheduled and were delivered: a success rate of ~70%, in line with previous years. The schedule was busy, but with high physics output. A major highlight of the year was the start-up of HIE-ISOLDE on 22 October. This ran on 74 Zn and 76 Zn, alternating between 4 MeV/u and 2.85 MeV/u during days and nights respectively. The INTC congratulates the technical teams for their success in realising this milestone, and acknowledges the strong support from CERN. A problem with the RF coupler limited the operation of the cryomodule cavities to running 6 hours a day, which is now understood to be due to RF heating and should be solved by cooling the coupler antenna. Building 508 is now fully operational with the installation of the user laboratories for solid state and laser spectroscopy, as well the DAQ and visitors room. 5.2 The number of protons received by ntof in 2015 exceeded the allocated number of , reaching a total of as initially requested. Numerous experiments were possible using C6D6 detectors and cross-section data on 70 Ge, 74 Ge, 76 Ge, 204 Tl, 242 Pu and 237 Np were possible in EAR1 and 171 Tm, 147 Pm, 33 S and 7 Be in EAR2. The commissioning of the EAR2 area continued throughout 2015, beam profiles were measured using MicroMegas and PPACs detectors. In addition, the recent installation of STEFF (SpecTrometer for Exotic Fragments) for the study of fission fragments in 10

11 EAR2, was completed towards the end of the year. The increasingly positive collaboration with ISOLDE was also noted. The Research Board took note. 5.3 Five experiments at ISOLDE were recommended for approval, for a total of 53 shifts, plus 3 shifts for target and ion source development for a further proposal. They are listed in the following paragraphs. There were no new requests for protons to ntof. 5.4 P443 Shape-coexistence and shape-evolution studies for bismuth isotopes by insource laser spectroscopy and beta-delayed fission in 188 Bi [9] was approved for 29 shifts and will be known as IS P444 Study of beta-delayed neutron decay of 8 He [10] was approved for 7 shifts and will be known as IS P448 Investigation of collectivity in N=Z nuclei: Coulomb excitation of 60 Zn [11] was granted 3 shifts for target and ion source development. 5.7 P449 Gamma and fast-timing spectroscopy of the doubly magic 132 Sn and its one- and two-neutron particle/hole neighbours [12] was approved for 17 shifts and will be known as IS ANY OTHER BUSINESS 6.1 E. Meschi presented the LHC schedule for The proton physics run is expected to start in the last week of April, with 160 days of pp physics foreseen along with the usual complement of Machine Development periods and Technical Stops days of special machine conditions are assumed, for high-beta* runs and Van der Meer scans, but their detailed scheduling will be decided later, at the LHC Performance Meeting (Chamonix 2016) in January. The year will end with 4 weeks of p-pb running. The Research Board approved the schedule. 6.2 The next meeting of the Research Board will be held on 9 March

12 ENCLOSURES 1. Minutes of the 124 th LHCC meeting held on 2-3 December 2015 (CERN-LHCC /LHCC-124). 2. Draft Minutes of the 119 th SPSC meeting held on October 2015 (CERN-SPSC /SPSC-119). 3. Draft Minutes of the 51 st INTC meeting held on November 2015 (CERN-INTC /INTC-051). REFERENCES [1] Minutes of the 213 th meeting of the Research Board (CERN/DG/RB /M-213). [2] Copies of the transparencies are available at [3] MoU for the GRADE (Generic detector pre-r&d At CERN ideasquare) programme (CERN-DG-RB ). [4] First addendum to the GRADE MoU for SIMPLE (Silicon Photo Multipliers for Generic Detector R&D) (CERN-DG-RB ). [5] Beam momentum scan with Pb+Pb collisions by NA61/SHINE at the CERN SPS (SPSC ). [6] Proposal: Search for solar chameleons and relic axions with CAST (SPSC ). [7] DUNE-PT: Proposal for a Full-Scale Prototype Single-Phase Liquid Argon TPC and Detector Beam Test at CERN (SPSC ). [8] Proposal for characterization of muon spectrometers for neutrino beam lines with the Baby MIND (SPSC ). [9] Shape-coexistence and shape-evolution studies for bismuth isotopes by insource laser spectroscopy and beta-delayed fission in 188 Bi (INTC ). [10] Study of beta-delayed neutron decay of 8 He (INTC ). [11] Investigation of collectivity in N=Z nuclei: Coulomb excitation of 60 Zn (INTC ). [12] Gamma and fast-timing spectroscopy of the doubly magic 132 Sn and its one- and twoneutron particle/hole neighbours (INTC ). 12