1 Operating, Maintaining, and Upgrading the LHC Detectors Sally Seidel University of New Mexico U.S. Department of Energy April 18, 2003

2 Faces in the future of the LHC program... Philip Watje (UNM ‘04) and Amanda Burghard (UNM ‘05) at work as technicians in the silicon laboratory at the University of New Mexico, characterizing production pixel sensors for ATLAS.

3 The salaries of these undergraduate students are provided by US-ATLAS. Without these funds, these straight-A physics majors would be supporting themselves with non-science minimum-wage jobs in Albuquerque. Because of this lab experience, they’ve begun talking about LHC Ph.D.’s. The LHC program is bringing research skills and excitement to the next generation right now. This talk is about the impact of detector maintenance and operations and detector upgrades on the science that they and we all want to do.

4 The ATLAS cryostat, a U.S. project Maintenance and Operations Through DOE support, U.S. universities’ scientists have built upon experience in previous large experiments and assembled teams that are producing major subsystems of the ATLAS and CMS detectors.

5 ~20 cm ~6,000 CMS Tracker Outer Barrel modules will be constructed in the U.S.

6 The U.S. Deliverables are on track to meet LHC schedules. This includes almost 50 university-based construction efforts. U.S. groups have provided leadership in many areas of design and construction. Outstanding examples of U.S. leadership on the LHC projects: U.S.-CMS constructing the entire forward pixel system responsible for endcap muon chambers and electronics leadership on hadron calorimeter barrel construction and all electronics

7 U.S.- ATLAS 7-university collaboration to build hundreds of square meters of the Monitored Drift Tube muon tracking detectors (25  m accuracy), including electronic readout and laser alignment 4-university collaboration building major portion of transition radiation tracker including advanced electronics

8 Hampton University’s clean room, where parts are prepared and tested for the ATLAS Barrel Transition Radiation Tracker

9 Maintenance and operations (M&O) includes final testing, including supplies alignment calibration integration monitoring maintenance, including spares, tooling support of common costs, consumables, surface infrastructure M&O activities train students and postdocs in the HEP state of the art. Continued leadership during the M&O phase is a natural path to leadership in extraction of the data.

10 U.S. M&O responsibilities are commensurate with the U.S. responsibilities during construction. Subsystem responsibilities by U.S. groups extend broadly and deeply in both ATLAS and CMS...

11 ATLAS M&O tasks deriving directly from construction responsibilities: Semiconductor tracker (SCT): subsystem management, system engineering, electronics coordination; monitoring, annealing, calibrating optical links; maintaining, monitoring flex hybrids...

12 Transition Radiation Tracker (TRT): checkout, integration, maintenance Liquid Argon Calorimeter (LAr): readout electronics, HV feedthroughs and cables, monitoring software, integration Scintillating Tile Hadronic Calorimeter (TileCal): pre-assembly, calibration, pre- operations Muon spectrometer: certification of chambers and alignment components, pre- operation, testing and debugging, system tests Trigger and data acquisition (TDAQ): software development, changes, and maintenance; troubleshooting and repair; rolling replacement of processors and network components

13 U.S. ATLAS skill mix needed to achieve the task of M&O

14 CMS construction responsibilities leading to M&O responsibilities: Silicon strip tracker (SiTrkr): full tracker outer barrel assembly Forward pixels (FPIX): full system

15 Electromagnetic calorimeter (ECAL): barrel transducers, front end electronics, laser monitor Hadronic calorimeter (HCAL): barrel and outer barrel, endcap and forward transducers and readout, endcap scintillator, and forward quartz fibers Muon system (EMU): cathode strip chambers, electronics, and readout Trigger/Data Acquisition (TRIDAS): Level-1 endcap muon and calorimeter triggers, DAQ filter

16 U.S. CMS M&O Estimated Personnel Needs

17 Upgrade LHC luminosity will increase during the first 4-5 years to cm -2 s -1. Modest LHC upgrades should increase luminosity to cm -2 s -1 after that, extending the observable mass range by 20%. Implications: increased radiation resistance needed in many systems. increased granularity of tracking needed. trigger innovations; rate capability management required. Timescale for upgrades: Timescale needed for R&D: starting now

18 Physics motivation for the luminosity upgrade: The full precision of the LHC detectors becomes attainable: Higgs measurements reach statistics comparable to systematics as H  Z  and H  and rarer modes become accessible. For 170 < m H < 200 GeV, final states with Higgs pairs are measured, allowing first measurement of Higgs self coupling. Precision measurements of boson self- couplings through triple and quartic diagrams improve substantially, in some cases comparable to electroweak corrections, probing extensions of the Standard Model for which these couplings are not uniquely fixed.

19 The discovery mass reach for new phenomena expands with increased access to rare high transverse energy and missing transverse energy events. Sensitivity to the scale of large extra dimensions improves by ~25%; the overall scale for discovery of new processes increases by ~30%.

20 Impact of accelerator luminosity on the detectors: baseline LHC operation may reveal new physics which would reasonably invite detector improvement. For L= cm -2 s -1, tracking systems require new technology and significant engineering for improved rad hardness (new materials, new geometries, small feature size electronics, cooling, power distribution) improved granularity (mean 10 4 tracks per crossing)

21 These new tracking technologies naturally lead to Improved precision at small radii (tagging short-lived particles such as b and  ) Improved precision at large radii (improved fractional accuracy of highest momentum tracks) In this environment, technologies that reduce detector mass and enhance triggering capability should naturally be examined as well. R&D for the current tracking systems began > 10 years ago.

22 Muon systems: may need additional shielding at high  when LHC data are available. improved angular coverage to observe decay chains of new rare decays and angular distributions of 2-body events, which are sensitive to new particle quantum numbers. Neutron fluxes in CMS endcap muon detector with present (top, |y|<2.4) and possible future (bottom, |y|<2) shielding.

23 Calorimeters: need new technologies for rad hard electronics studies required of space charge effects, current-induced voltage drops new liquids and gasses should be examined |y|=2

24 Trigger, DAQ systems should respond dynamically to discoveries and opportunities: Level 1 must respond to reduction of bunch crossing interval High level triggers must respond to increased rate and event size Associated research in readout network, complexity handling, implementation of network technology should keep pace. Integration (services, support, interfaces, beam pipe) for all above.

25 Support for LHC Research has 2 components: The Research Program, which supports engineers, computer professionals, technicians, and Tier 1 and 2 facilities The Base Program, which supports physicists, including post-docs. The success of the LHC program depends on increased support of the Base Program as well as the Research Program.

26 U.S. ATLAS Research Program projected costs, FY’03-’07 U.S. CMS Research Program projected costs, FY’02-’08

27 The presence of U.S. physicists at CERN needs to start growing now to meet commissioning responsibilities. Estimated total FTE persons in US-ATLAS Base Program:

28 A planned increase in Base Program support is needed for physicists who will be working at CERN: Example from US-ATLAS Some 6-12 month visits to CERN by US faculty will be essential. CERN has no mechanism to support sabbatical salary.

29 Travel costs will necessarily increase. Costs are estimated from predicted number of trips and average length of time of each trip. Cost/trip is greater than for domestic experiments.

30 DOE funding for proton research is decreasing (see J. O’Fallon talk at HEPAP, 3/7/2003). We urge DOE to increase Base Program support for LHC scientists in balance with the Research Program.

31 A conclusion... by training the next generation of high energy physicists, and in supporting LHC experiment maintenance, operations, and upgrade R&D......DOE is investing in the scientific and technological future of the U.S.