NuMI-L-325 January 22, 1998 D. Ayres Minutes of the MINOS Collaboration meeting at Fermilab December 6-7, 1997 Present: Argonne: Dave Ayres, Maury Goodman, Tacy Joffee-Minor, William Leeson, Larry Price, Paul Schoessow, Rich Talaga, Jonathan Thron Caltech: Brajesh Choudhary, Yinzhi Huang, Hwi Kim, Doug Michael Dubna: Yuri Gornushkin, Misha Ignatenko Fermilab: Bruce Baller, Bob Bernstein, Jim Hylen, Cat James, Jim Kilmer, Gordon Koizumi, Scott Menary, Jorge Morfin, Adam Para, Dave Pushka, Gina Rameika, Linc Read, Wes Smart, Alan Wehmann, JC Yun Indiana: Chuck Bower, Dick Heinz ITEP-Moscow: Igor Trostin Lebedev: Vladimir Ryabov Livermore: Peter Barnes UC London: Jenny Thomas Minnesota: Pete Border, Tom Chase, Hans Courant, Prisca Cushman, Ken Heller, Marvin Marshak, Bill Miller, Jeff Nelson, Earl Peterson, Keith Ruddick, Reinhart Schwienhorst Oxford: John Cobb, Hugh Gallagher, Colin Perry, Nick West Rutherford: John Alner, Peter Litchfield, Saeed Madani Stanford: Carlos Arroyo, George Irwin, Stan Wojcicki Texas A&M: Masoud Vakili, Bob Webb U. Texas, Austin: Karol Lang Tufts: Tony Mann, Bill Oliver, Jack Schneps Visitors: Larry Wai (U. Washington) Transparency copies, minutes of MINOS committee meetings held in conjunction with this collaboration meeting, and NuMI technical reports distributed at the meeting are available as NuMI notes: Executive Committee minutes: NuMI-L-324 Institutional Board minutes: NuMI-L-326 Technical Board minutes: NuMI-L-327 Transparency Xeroxes: NuMI-L-328 Neutron sensitive scintillator: NuMI-L-329 Joint steel and installation meeting: NuMI-L-333 Electronics working group meeting: NuMI-L-338 The general collaboration meeting on Saturday and Sunday was preceeded by a meeting of the scintillator working group on Friday evening. The scintillator meeting was continued on Saturday afternoon, early Sunday morning, and finally completed on Sunday afternoon. On Monday, Dec. 8 there was a joint meeting of the steel and installation working groups (see NuMI-L-333). In parallel with this, the electronics subgroup met at Argonne on Monday and Tuesday, Dec. 8 and 9 (see NuMI-L-338). Copies of transparencies from only a few of the talks at these working group sessions are included in NuMI-L-328. There were no parallel sessions held during the general collaboration meeting. A. MINOS and NuMI updates Stan Wojcicki summarized significant MINOS developments since the September Collaboration meeting: 1. The MINOS Progress report to the Fermilab PAC (NuMI-L-300) was written, submitted and presented at the October 17-19 PAC meeting. The resulting letter from John Peoples discussed low energy running and tau identification, and scheduled the next MINOS presentation for the May 15-17 PAC meeting. 2. Serious MINOS electronics design work has now begun, following plans made at the electronics meeting at Rutherford in November. 3. The MINOS steel plane prototype program is being transferred from Livermore to Fermilab as a result of budget and schedule constraints. We hope to have the single plane prototype completed in time for the April 15-17 Lehman Review. 4. Peter Litchfield has been elected by the U.K. MINOS institutions to be the U.K. spokesperson for MINOS. The U.K. groups' presentation to the PPESP in December was well received. R&D funding for 1998 was approved and the committee showed some willingness to discuss funding for MINOS construction. The written report from this meeting is expected later this month. 5. The Gilman Subpanel's recommendations for the U.S. HEP program will be presented in February. There is still time for MINOS supporters to send their comments and opinions to the subpanel. 6. The MINOS detector TDR must be submitted to Fermilab for an internal review in March 1998, prior to its submission to the Lehman Panel for its April 15-17 meeting. The major purposes of this review are to validate the NuMI Project baseline budget and schedule, as well as the specific NuMI funding requests for FY 1999 and FY 2000. 7. Stan reviewed the implications for MINOS of recent oscillation results from SuperKamiokande, Soudan 2 and CHOOZ. 8. Stan listed the issues for this meeting as: a. Planning for the TDR: definition of its scope and assignment of tasks, and a discussion of policy issues (e.g., low energy, emulsions). b. Discussion of a possible MINOS test beam run: there will be no Fermilab test beam running until after April 1999 (perhaps much later than April, so MINOS might have to find another test beam). There is the possibility of running at Brookhaven in the June-December period, but we will have to express our interest in this, and organize our efforts, very soon if want to run there. The Technical Board will make a decision on this question at the end of this meeting (see NuMI-L-327). c. Planning for MINOS meetings after Austin, including the 1998 week-in-the-woods: see the final section of these minutes for the schedule which was agreed to at this meeting. Gina Rameika summarized the current status of the NuMI Project, which has made good progress on technical, management and ES&H issues since the September MINOS meeting. NuMI ES&H documents have been sent to State officials in Illinois, Minnesota and Wisconsin. We hope to have "finding of no significant impact" statements by the end of the calendar year. The NuMI project is developing a detailed WBS which identifies tasks, resources and technical requirements. Following the example of the Main Injector Project, these will be summarized in a Technical Design Handbook, which is a "living" version of the project TDR. She described the key issues for the April Lehman review as: definition of the Total Project Cost (TPC), project management and schedules (Bruce Baller will be responsible for MINOS) and technical requirements for the beam and the detectors. Lehman has already validated NuMI requirements for FY 1999, and will look at the proposed NuMI funding for FY 2000 at the April meeting. Gina said that Fermilab is in the process of hiring an engineer who specializes in underground tunneling construction. Bruce Baller reviewed the new Fermilab organization for managing the MINOS project. (Bruce is now head of the new MINOS Department within the Particle Physics Division.) He described recent MINOS Department activities: He has submitted a hazard assessment form to the new PPD ES&H Committee chaired by Keith Schuh. Fermilab's FY 1998 MINOS R&D budget is now $950k plus $50k for overseas visitor support. Bruce listed the major R&D activities to be supported by these funds as: steel plane prototypes at Fermilab, scintillator light yield studies, photodetector evaluation, scintillator module assembly and handling, and TDR design work to define the MINOS baseline detector. MOU's are now being drafted between Fermilab and MINOS institutions to perform this work. Bruce described the new Work Breakdown Structure which he is developing for MINOS, and gave the names of the WBS Level 2 managers which he has appointed: Steel/magnet -- Jim Kilmer, Active detector fabrication -- Doug Michael, Far detector installation -- Dave Ayres, Near detector installation -- Cat James, Electronics/DAQ -- Jonathan Thron plus a U.K. co-manager, to be determined. Finally, Bruce announced that Adam Para has been appointed as the PREP liaison physicist for MINOS. Bill Miller and Earl Peterson summarized recent Soudan site preparation activities. MINOS lease negotiations are still progressing slowly. Design of the shaft cage needs to be finalized soon, so it is very important for steel engineers to check that the proposed cage specifications are correct. Studies of heat flow are now being made in the mine shaft and drifts to determine the impact of the expected heat generation by MINOS. The Soudan 2 utilities will be rerouted in January so that MINOS test blasting can be performed in February along the rock wall which will eventually become the entrance to the MINOS cavern. These blasts will help to determine the effect MINOS excavation will have on the Soudan 2 detector modules. Equipment is also being rearranged in the existing Soudan 2 cavern in preparation for MINOS installation, and to accommodate the Cryogenic Dark Matter Experiment (which will begin operation about the same time MINOS excavation work begins). Engineering design work on the MINOS cavern itself is continuing as part of the bid package preparation process. B. New physics results There was a series of reports on new physics results which have an impact on the optimization of the MINOS detector design: 1. SuperKamiokande (by Larry Wai, now at Washington but soon to move to Stanford to work on MINOS). 2. Soudan 2 (by John Cobb), 3. CHOOZ (by Maury Goodman), 4. Possibilities for neutrinos from the proposed muon collider at Fermilab (by Maury Goodman). Transparency copies from these talks are included in NuMI-L-328. C. Technical progress reports 1. Steel. Jim Kilmer described Fermilab's plans to complete the assembly of the 2-cm thick steel plane prototype which was started by the Livermore group. This will take place in the new muon lab, and will eventually be expanded to include several prototype steel and detector planes. The single plane is scheduled to be mounted onto the support rails one week before the April Lehman Review. One potential advantage of the new muon lab is the possibility of a useful flux of horizontal muons through the prototype planes during (short) KTeV calibration runs. 2. Electronics. Jonathan Thron summarized the discussions at the Rutherford electronics meeting (described in detail in NuMI-L-318) and invited people to attend the continuation of these discussions at meetings to be held at Argonne on the Monday and Tuesday immediately following this meeting (see NuMI-L-338). 3. Near detector. Jenny Thomas described progress in optimizing the design of the near detector. The 1-inch thick octagonal steel planes are 6 m wide but otherwise similar to the far detector planes. The plane spacing over the entire detector length is the same as in the far detector. The detector is divided into four sections along its length, starting at the upstream end (with steel thicknesses given in ()'s): veto (0.5 m), target (1.0 m), hadron shower (1.5 m) and muon spectrometer (4 m). Physical lengths (including gaps between planes) will be about twice those given above, for a total of about 14 m. The beam will be centered halfway between the central coil hole and one vertical edge, with only one quarter of the octagonal area instrumented in the first three sections. The full area of the muon spectrometer will be instrumented, but with detector planes only in every fourth gap. With no optical summing, this will require 8640 channels of scintillator strips in the first three sections and 5840 channels in the muon spectrometer section, for a total of 14,500 channels. Approximately 100 m upstream of the detector should be open drift space to reduce the flux of muons from neutrino interactions in upstream material. Overlapping events are not expected to be a problem in the near detector with the planned 1 msec beam spill, if the detector time constants are as expected and the electronics time resolution is 100 nsec or better. 4. Integration. Jim Kilmer summarized the "integration" issues which have been raised by Rick Milburn in NuMI-L-314. This is primarily a "call to arms" to MINOS engineers to address a number of difficult engineering questions which have been ignored up to now as being too detailed for the conceptual design stage of the project. Many of these issues concern the installation of the detector planes and of the magnet coil. These were discussed in detail at the joint meeting of the steel and installation working groups which occurred immediately after the main meeting, on Monday, December 8. The minutes of this meeting are available as NuMI-L-333. 5. Neutrino beam. Jim Hylen summarized recent progress on the NuMI neutrino beam design. Following the recommendations from the Rutherford electronics meeting, the fast-spill (10 usec) narrow-band beam (which would allow the use of lithium lens focussing) is no longer being pursued. The depth of the NuMI target hall is being optimized to minimize civil construction costs. The design of the target pile structure is also being optimized so that specifications can be provided for the Technical Requirements Document, which will be the basis for the NuMI TDR cost estimate. The pile design must provide adequate radiation shielding while allowing for the servicing of target components and giving the flexibility for alternative beam configurations such as the narrow band beam and low energy running. An alternative technique for shielding the decay pipe is being developed to provide more flexible shielding at lower cost. Shielding would be concentrated in a few regions where the hadron beam is deliberately collimated to remove halo. Finally, the hadron absorber (beam dump) at the end of the decay pipe is being designed. Work on the hadronic hose has progressed slowly while an improved aluminum alloy wire has been identified. While this technique still looks promising, there has been no decision to proceed with it and it will not be in the WBS cost estimate of technical components. 6. Improved MINOS energy resolution. Vladimir Ryabov described a method for improving MINOS energy resolution for hadrons by enhancing the detection of neutrons from ~10% in the current design to >50%. This would require measuring neutron interactions in a 3-500 usec time window after each neutrino event, and enhancing neutron detection by one or more methods: Doping the scintillator with 10-B or 6-Li admixtures to capture thermal neutrons, doping the scintillator with cadmium or gadolinium which have very large cross sections for neutron capture, and/or inserting layers of cadmium or gadolinium next to scintillator layers. Test beam measurements have confirmed that neutron detection would be greatly improved by these techniques. See NuMI-L-329 for a detailed description of this proposal. A number of questions were raised in the ensuing discussion: How much would energy resolution improve in the few GeV region? Could the technique work at all in the near detector, where a long neutron time window would cause severe overlap problems? Could we get some benefit by using information from the neutron detection efficiency which already exists in the baseline design? 7. Scintillator working group summary. Doug Michael summarized his conclusions from the four scintillator working group meetings which were held over the past three days. The short term goals of the group are to provide technical information for the TDR, including engineering optimization and costing of the baseline design, to set the stage for post-TDR R&D, and to involve new groups in the scintillator development work. Goals for the post-TDR era include final optimization of the design by about spring 1999, engineering for production, preparing large scale prototypes and studying performance in test beams. Doug listed people and institutions who are currently working on scintillator R&D. He said that three general issues are now driving development work: defining a time scale for decisions needed for the baseline cost estimate, defining a limited scope for future decisions, and developing a plan for post-TDR R&D and preparation for production. Doug then described the specific technical issues which must be addressed soon. The common themes relating these are improved light output, improved understanding of costs, and understanding of calibration techniques. He summarized work going on in the specific areas of WLS fibers, scintillator extrusions, assembly of scintillator strips and fibers, engineering of scintillator module construction, optimization of the optical readout chain design, optimization of the photodetector choice, and calibration techniques. D. Software and simulations John Cobb summarized recent work on the simulation of the nu_mu CC energy test by David Petyt at Oxford. The goal of this work is to investigate, at both high and low neutrino energies, the sensitivity of the CC energy test as a function of delta m^2, including the effects of systematic errors. The high energy simulation uses the standard 17 GeV WBB, while low energy uses an approximation to a ~5 GeV WBB (for which no design yet exists). The low energy scale chosen is determined by the recent SuperK results combined with the low energy neutrino event rates potentially achievable at NuMI. Algorithms were devised for selecting events, calculating energies, and fitting and comparing energy spectra at high and low energies. Systematic errors were calculated for near-far comparisons of the event rates, energy scales, and energy spectra. The study concluded that: 1. Delta m^2 sensitivities are 0.005-0.2 eV^2 for the high energy beam and 0.002-0.05 eV^2 for the low energy beam. In both cases, beam energies are a factor of 2 to 3 higher than optimum for the Kamiokande (0.01 eV^2) and SuperK (0.003 eV^2) delta m^2 values, respectively. 2. The NC/CC test is harder with the low energy beam. 3. Systematic errors are a problem only for small signal levels. In particular, sensitivity at the sin^2(2 theta) = 0.1 level will be difficult to achieve. There was an extended discussion of the possibility of implementing all MINOS software in Object Oriented (OO) technology. Nick West summarized the dilemma which confronts the collaboration. Although conventional Fortran-based software would be adequate for all anticipated MINOS software tasks, support for many necessary tools (ZEBRA, ADAMO, GEANT, CERNLIB,...) will be disappearing around the time that MINOS turns on because of the planned HEP migration to OO based software. While OO technology has a number of fundamental advantages for us, we have no experience with it and many of the tools we would need do not yet exist in usable forms. Substantial MINOS manpower would be required to implement collaboration software as an OO system, perhaps more than we can supply and more than would be required to turn the present software into a complete, user-friendly system. However, maintenance of Fortran-based software in the future will require significantly more manpower to compensate for increasingly fragmented support. CERN's plan to move to OO-based software is of particular concern. Nick outlined the major elements of a possible migration path for MINOS to OO. It would require a full commitment from the entire collaboration, and development of the current GMINOS software would have to be stopped. An OO working group has been set up to understand the most important technical issues and their impact on MINOS. It was agreed that this group will develop a detailed plan and a demonstration of OO suitability for MINOS, and an estimate of the manpower required. We should aim for making a decision about whether or not to implement MINOS software in OO at the June workshop in Ely. E. TDR planning Stan Wojcicki described his plan for organizing work on the MINOS Technical Design Report. The immediate goals are to determine the scope of TDR related tasks, assign responsibilities, and agree on a schedule of milestones and deadlines. He listed a number of open questions, which Bruce Baller agreed to investigate. Summaries of answers found by Bruce are given in []'s: a) What are the real deadlines? [TDR and related documents must be submitted to DOE on March 16. An internal review by Fermilab must completed before then.] b) How detailed (long) does it have to be? [As detailed as possible. The RHIC STAR detector TDR is a good model.] c) Does text have to follow the WBS structure? [No, but there should be a close correspondence.] d) Are schedule, cost, management covered in a separate document? [Yes, separate documents are required for costs and schedules, and for the management plan.] e) How is R&D effort described (e.g. test beam work)? (In a separate chapter or as part of related WBS element chapters?) [R&D should be included in each individual chapter.] f) Is use of the Soudan 2 detector covered in the TDR? [It can be included if we like, although it is not included in the TPC.] g) How is the TDR for Soudan cavern excavation and outfitting handled? Who is responsible? Who else will work on it? [Roger Dixon and Earl Peterson will prepare the Soudan cavern TDR.] The Fermilab NuMI and MINOS groups and the MINOS collaboration are jointly responsible for the production of the TDR and related documents, with the details to be worked out during the next few weeks. Dave Ayres, Bruce Baller and Stan will be responsible for overall editing of the detector TDR document. Stan listed his proposal for the structure of the TDR, including writing responsibilities. Chapter Leader/Workers ------- -------------- Physics Wojcicki/Goodman Scintillator Michael/Lang, Chase, Ruddick, Cushman Steel Kilmer/Read, Barnes Electronics & DAQ Thron/Cobb Far detector installation Ayres/Miller, Alner Near detector installation James/Thomas, Bernstein Software & computing Litchfield/Para "Scope contingency" (?) Para/Heller Emulsion detector Schedule Costs Management F. Schedule of MINOS meetings and deadlines The current schedule of MINOS meetings and deadlines is shown below. This schedule has been updated from the version which was agreed to at the end of the meeting. Outlines of MINOS TDR Chapters due Dec 15 (Mon) Meeting of SOC at Fermilab Jan 14 (Wed) Meeting of TDR organizers at Fermilab Jan 15 (Thu) Visit to DOE headquarters Feb 12 (Thu) MINOS meeting at Austin Feb 14-15 (Sat-Sun) MINOS Detector TDR submitted for NuMI review Mar 2 (Mon) Submit TDR and related documents to DOE Mar 16 (Mon) MINOS meeting at Fermilab (proposed) Mar 28-29 (Sat-Sun) NuMI/MINOS Lehman Review Apr 15-17 (Wed-Fri) Fermilab PAC meeting (present MINOS TDR) May 15-17 (Fri-Sun) MINOS Week in the Woods Workshop in Ely Jun 15-21 (Mon-Sun) MINOS meeting at Fermilab (proposed) Aug 14-17 (Fri-Mon) MINOS meeting in London (proposed) Oct 3-4 or Oct 10-11 (Sat-Sun) MINOS meeting at Fermilab (proposed) Dec 5-6 (Sat-Sun)