NuMI-L-386 August 23, 1998 D. Ayres Minutes of the MINOS Collaboration meeting at Ely June 15-21, 1998 Present: Argonne: Dave Ayres, Gary Drake, Tom Fields, Vic Guarino, Maury Goodman, Rich Talaga, Jonathan Thron, Ken Wood Caltech: Brajesh Choudhary, Yinzhi Huang, Hwi Kim, Nat Longley, Doug Michael Dubna: Misha Ignatenko Fermilab: Bruce Baller, Bob Bernstein, Norm Bosek, Sam Childress, Jim Hylen, Cat James, Jorge Morfin, Adam Para, Rob Plunkett, Gina Rameika, Linc Read, Wes Smart, Jae Yu, JC Yun IHEP, Beijing: Tao Hu Indiana: Chuck Bower, Dick Heinz, Lynn Miller, Stuart Mufson, Jim Musser Livermore: Peter Barnes London: Jenny Thomas Minnesota: Jim Beaty, Pete Border, Tom Chase, Hans Courant, Prisca Cushman, Tony Hase, Arjan Heering, Ken Heller, Marvin Marshak, Jerry Meier, Bill Miller, Jeff Nelson, Keith Ruddick, Rajiv Shivane Oxford: John Cobb, Colin Perry, Nick West Protvino: Vladimir Kochetkov Rutherford: John Alner, Rob Edgecock, Saeed Madani, David Petyt Stanford: Carlos Arroyo, Robert Hatcher, George Irwin, Stan Wojcicki Sussex: Phil Adamson Texas A&M: Bob Webb U. Texas, Austin: Karol Lang Tufts: Rick Milburn, Bill Oliver, Jack Schneps W. Washington Louie Barrett Visitors: Leon Bosch (DEP), Richard Boyd (Ohio State), Gary Feldman (Harvard), Russ Hobbie (Minnesota), M. Komatsu (Nagoya), Ron Lutha (DOE-Fermilab), Donna Naples (Kansas State), Lee Petersen (CNA), Jake Waddington (Minnesota) Transparency copies and minutes of MINOS committee meetings held in conjunction with this Collaboration meeting are available as NuMI notes: Transparency Xeroxes: NuMI-L-384 Executive Committee minutes: NuMI-L-385 Institutional Board minutes: NuMI-L-387 A. Summary This third annual MINOS week-in-the-woods meeting was held at Vermilion Community College in Ely, Minnesota. It included plenary sessions and nine hours of parallel working group meetings. Much discussion concerned reaction to the recommendations of the "Baltay" physics review of the experiment, which was held three weeks earlier, and preparation for the Fermilab Director's Review of the NuMI and MINOS projects, which was held three weeks after the end of this meeting. The Baltay subcommittee's concern about MINOS sensitivity at very low Delta m^2 can probably be addressed better with atmospheric neutrino events in the far detector than with low energy beam running, but this remains to be demonstrated. Following Jim Hylen's description of the new neutrino beam "zoom" design, which uses two movable parabolic horns to obtain high neutrino fluxes over a wide range of energies, the Collaboration decided to adopt this "PH2" beam design, tuned for the medium energy 3-10 GeV range, as the new baseline for the experiment. The near detector working group decided that all scintillator strips (in the new squashed steel geometry) should be read out from only one end, that every fifth plane in the upstream sections should be fully instrumented, and that multiplexing should be used only in the muon spectrometer section. An ad hoc steel and magnet panel considered a number of questions posed by Jim Kilmer's engineering group at Fermilab. They reviewed the draft specifications for the four-plane prototype steel procurement and the coil design constraints. The scintillator working group discussed many possible techniques for increasing light yield, made detailed plans for near term R&D work and worked out a technically driven construction schedule. They proposed a detailed plan for making the final photodetector decision in February 1999. Many aspects of the MINOS hybrid emulsion detector design were discussed by a large and active working group. Other working groups included beam monitoring, software, electronics and far detector installation. Specifications for NuMI civil construction work at Fermilab and Soudan are nearing the "Title I" stage. After about the end of July, construction drawings and specifications will be finalized, and it will become increasingly expensive to make changes in the designs of these facilities. Two draft documents describing the facility designs were distributed at the meeting to solicit collaboration input. Sam Childress asked for comments on the current draft of Chapter 5 of the NuMI TDR, "Construction Criteria for the NuMI Experimental Facility," and Lee Petersen asked the Collaboration to review the "MINOS Far Detector Laboratory Design Development Report," which will be the basis for the bid package for the Soudan excavation contract. Gary Feldman presented the application by the Harvard University HEP group to join the MINOS Collaboration. Richard Boyd (Ohio State) described a proposal to use the MINOS far detector to identify supernova neutrino NC events by observing neutrons from excited states of iron. The tour of the Soudan Underground Laboratory was cancelled by a lightning strike which caused a power outage at Soudan. An excellent Collaboration Dinner was hosted by Bill Miller and his family at Everett Lake on Saturday afternoon and evening. The MINOS Executive Committee and Institutional Board met during this meeting, but the Technical Board did not. A current schedule of MINOS meetings and deadlines is included below as the final section of these minutes. B. MINOS update Stan Wojcicki summarized significant MINOS developments since the March Collaboration meeting and described the goals of the Ely meeting: 1. The report of the "Sanders" Director's review of MINOS, held at the end of April, is now available. They concluded that we are not yet ready for a Lehman Review, and made many useful recommendations. (The report is NuMI-L-382, and the Collaboration response to it is NuMI-L-399.) 2. The report of the "Baltay" PAC subcommittee physics review of the experiment is now available. This report was approved by the PAC at its Aspen meeting, immediately after the Ely meeting. The subcommittee concluded that the physics case for MINOS is strong, but that we cannot cover the lowest Delta m^2 part of the Super-K suggested region. (The final report is available as NuMI-L-389.) 3. The Super-K Collaboration presented strong evidence for atmospheric neutrino oscillations at the Neutrino 98 conference in Takayama, Japan. Stan summarized this result and other evidence for oscillations presented at that conference. 4. An emulsion workshop was held in Nagoya, Japan immediately prior to the Ely meeting. It was attended by about 40 participants, including several proponents of the MINOS hybrid emulsion detector. 5. Tom Fields will take over from Gina Rameika as NuMI Project manager on July 1. Gina has served as Project Manager for the past three years. 6. The Fermilab PAC will consider the report of the Baltay PAC subcommittee at its Aspen meeting next week. The main issues raised by the report are: a) How likely is Delta m^2 ~ 5 x 10E-4 eV^2? b) What is MINOS sensitivity below Delta m^2 = 1 x 10E-3 eV^2? c) What is the sensitivity of an emulsion experiment at low Delta m^2? 7. The July 13-15 Director's Review will review the entire NuMI Project for the first time; it also will consider progress made in MINOS detector work since the April (Sanders) Director's review. 8. Peter Rosen is meeting with CERN Director designate Maiani next week, and may discuss a possible international review of neutrino experiments. 9. Stan listed the following goals for the Ely meeting: a) Bring everyone up to date on the latest developments in physics, technology, politics, etc. b) Review the status of NuMI. Do we need broader MINOS Collaboration involvement in NuMI? c) Review progress for the July Director's Review: Responses to the Sanders' Committee recommendations, cost estimates, and the status of changes to be made to the TDR. d) Agree on an appropriate response to the Baltay subcommittee report. e) Define technical goals for the near future, especially in scintillator and photodetector R&D, emulsion experiment plans, simulations, and MINOS magnet issues. f) Define plans for software development. C. New physics results and models Talks in this session included: 1. David Petyt discussed three flavor mixing and the status of neutrino oscillation phenomenology in light of recent results. 2. Gary Feldman described a unified approach to the classical statistical analysis of small signals, now known as the Feldman-Cousins methodology and published in Phys. Rev. D57, 3873 (1998). 3. Maury Goodman gave an updated summary of neutrino mass scenarios. 4. Doug Michael reviewed the Super-K results presented at Takayama. D. Status of NuMI and Soudan Talks in this session included: 5. Gina Rameika gave an overview of the NuMI Project funding, schedule and preparations for the Lehman Review. 6. Tom Fields gave the Collaboration his thoughts on the possibility of accelerating funding for the project. 7. Jim Hylen described the new PH2 "zoom" design for the NuMI wide band neutrino beam, which could replace the 3-horn H66 design as the project baseline. (This change was later approved by the Collaboration.) 8. Sam Childress described the status of, and plans for, the NuMI facility construction, and asked for Collaboration input on Chapter 5 of the NuMI TDR, "Construction Criteria for the NuMI Experimental Facility." Copies of this document were made available for review, and a special session was organized near the end of the Ely meeting to discuss suggestions for changes. 9. Bill Miller gave an update on Soudan site preparation plans. He noted that the excavation is now scheduled to begin in January 1999, three months later than previously. Later in the week, CNA distributed draft copies of the "MINOS Far Detector Laboratory Design Development Report" for Collaboration review. This document will be the basis for the Soudan excavation bid package. 10. Dave Ayres and Bruce Baller reviewed the current status of the TDR and CSP documents which are being prepared for the Lehman Review. The drafts submitted to the April Director's Review will be updated for the July Review. E. Scintillator The following talks were presented in this session: 11. Overview of scintillator issues: Doug Michael. 12. Scintillator production: Rich Talaga. 13. Light yield measurements: Rich Talaga, Brajesh Choudhary. 14. WLS fibers & measurements; aging studies: Doug Michael, Brajesh Choudhary. 15. New scintillator module design: Tom Chase. 16. Clear fibers and connectors: Stuart Mufson. 17. Multiplexing boxes: Lynn Miller. 18. New module tests at Fermilab: Misha Ignatenko, Hwi Kim. 19. Impact of light yield on physics: Doug Michael. 20. Module production and test equipment; production plans: Vic Guarino. 21. Calibration plan: Jenny Thomas. 22. Scintillator cost and schedule: Doug Michael. 23. Electronics for baseline design: Jonathan Thron. 24. Extensions to the baseline design -- R&D overview: Doug Michael. 25. Two fiber and L16 options: Brajesh Choudhary. 26. Photodetector issues and status report: Prisca Cushman. 27. DEP HPD design constraints: Leon Bosch. 28. Electronics architecture for HPD option: Colin Perry. 29. Possible HPD architectures: Prisca Cushman, Jim Musser, Bill Oliver. 30. WLS fiber arrangement changes to improve light output: Ken Heller. 31. Plan for evaluation of HPDs and HPD detector architectures: Doug Michael. 32. Scintillator R&D issues and milestones: Doug Michael. F. Near Detector The following talks were presented in this session: 33. Near detector design requirements and overview: Jenny Thomas. 34. Beam systematics: Jim Hylen. 35. Beam systematics and parameter measurement: David Petyt. 36. Beam monitoring and physics sensitivity: Jorge Morfin. 37. Alignment and survey uncertainties: Wes Smart. 38. Near hall design: Cat James. G. Low energy, low Delta m^2 The following talks were presented in this session: 39. Low energy beam design: Jim Hylen. 40. T test at low energy: David Petyt. 41. Disappearance test and parameter measurement at low energy: Carlos Arroyo. 42. GMINOS generation of atmos. neutrinos: Rob Edgecock, for Peter Litchfield. 43. Nu_tau's from atmos. oscill. in emulsion?: David Petyt for P. Litchfield. 44. Halfway point observations, thoughts, discussion: Stan Wojcicki. How can we improve low Delta m^2 sensitivity? Near detector design issues: 1-ended vs 2-ended, MUX vs no-MUX. Scintillator issues: How much light is needed? How do we assess risks? Key hardware R&D issues. Thoughts on HPDs. 45. HPDs versus PMTs: Doug Michael. H. Software The following talks were presented in this session: 46. Introductions to OO: Peter Border, Nick West. 47. OO for MINOS GEANT (GoMinos): Hwi Kim. 48. OO application to neural net analysis: George Irwin. I. Emulsion experiment The following talks were presented in this session: 49. Physics issues for emulsion experiment: Maury Goodman. 50. Emulsion detector design: Adam Para. 51. Optimization of detector design -- choice of materials: Stan Wojcicki. 52. Background from Charm production: John Cobb for Hugh Gallagher. 53. Emulsion detector simulation: Robert Hatcher. J. Overseas experiments The following talks were presented in this session (not all "overseas"): 54. Use of MINOS as a supernova neutrino detector: Richard Boyd. 55. Gran Sasso long baseline expts -- Aquarich, Icarus, Opera: Jack Schneps. 56. Gran Sasso long baseline expts -- NOE, NICE: Doug Michael. K. Other talks The following special talks and discussion sessions were held during the meeting plenary sessions: 57. Discussion of meeting schedule for the coming year: Stan Wojcicki. 58. Feedback on Fermilab civil construction criteria: Sam Childress. 59. Application by the Harvard high energy group to join MINOS: Gary Feldman. 60. Plans for TDR and CSP revision for July Review: Dave Ayres, Bruce Baller. L. Working group summaries 1. Neutrino beam monitoring Jorge Morfin reported on the discussions of this working group, which were mainly aimed at bringing MINOS Collaboration members up to date with current plans for beam monitoring, and encouraging their participation in this work at Fermilab. The goals of the monitoring system are to observe and control, on a "spill-to-spill" time-scale, changes in the beam energy spectrum and intensity which are caused by variations in horn currents, positions, and other beam parameters. Large area SWICs, operated in the ionization mode, would be used to monitor the hadron beam intensity and position upstream of the decay pipe and upstream of the hadron absorber. Large area SWICs would also be used as muon detectors to monitor intensity and position at three or four positions within the shield downstream of the hadron absorber. Previous studies of required sensitivities need to be redone for the new PH2 beam designs. It is already clear that the required sensitivities can be obtained with the proposed monitor system to control the movement of the magnetic centers of the horns, but it is not yet clear if similar control over the horn currents will be possible. Jorge noted that if control of the horn currents at the required level was not possible via the muon/hadron monitors, it would be possible on the time-scale of a day to use the information from the MINOS near detector to determine the effective horn current. Possible muon "outrigger" counters at Soudan have not been studied yet, and are not included in the design or cost estimate. 2. Software Robert Hatcher summarized the discussions in the software working group sessions by listing software tasks for short, medium and long time scales. In the short term, simulations will use the existing software system to understand the effect of light yield, electronics design, magnetic field properties and near detector design on the most "fragile" physics sensitivities. Evaluation of the impact of low light levels on low energy beam data is a particularly high priority task for the next two months. In the medium term, work is needed on an event display, the database specification and a transition plan from GEANT3 to GEANT4. In the long term, the job list depends on whether we pursue an OO or a non-OO route. If we choose non-OO, we need to understand how to live with software which is no longer well supported, such as ADAMO, ZEBRA and GEANT3. But even in the short term, a low level of effort is already being devoted to understanding the suitability of OO tools for MINOS, with quite encouraging results. Practical experience is being gained (at a very basic level) with GEANT4 (with ROOT I/O), databases, and event displays. The MINOS Hypernews facility will be used as a forum for OO education and communication. Robert noted that much more manpower will be needed to accomplish these software tasks on the required time scale. 3. Electronics Jonathan Thron reported on the activities of the electronics working group. Following the MINOS meeting with Viking engineers in U.K., the group has agreed that, if the HPD/Viking route is chosen, it would be best to buy all our chips from a single production run, that we should work closely enough with Viking to get a better feeling for the risks of relying on them as a sole source, and that a "plug-and-play" switch from PMT to DEP/Viking electronics at a late stage is not practical. In the short term, the Oxford group will build a "toy" prototype front end for the PMT baseline to evaluate our sensitivity to some specific concerns, e.g., magnetic field sensitivity, noise from welding and other sources, and operation with one photoelectron signals. The electronics and far installation working groups held a joint meeting at Ely to discuss quiet power distribution, grounding plans, and location of electronics racks. 4. Steel and magnet panel Rick Milburn summarized the recommendations of the ad hoc steel and magnet panel, which was appointed by Stan to respond to a request for guidance from Jim Kilmer's Fermilab engineering group. The panel reviewed the draft specifications for steel plates to be used for the four plane prototype studies; these were patterned after those used to purchase very similar magnet steel for BaBar. The panel found them to be acceptable, providing that the expected 10% variation in magnetic field due to steel properties could be measured well enough to correct the data. The panel did not consider the near detector field plots provided, but referred these to Jenny Thomas for evaluation. The panel defined the basic specifications on the coil design to be that (1) coil induced temperature rise at the surface of the coil hole should be less that 3-5 deg C, (2) the return coil should be routed as far as possible from the photodetectors and electronics, and (3) the present spacing of 1.5 m between supermodules should be maintained or reduced. Bar code labelling of steel plates should make the history of each plate available to the database. Plates for the four plane prototype should include the extra holes required for bundling and rigging them down the Soudan mine shaft, so that this procedure can be tried at Fermilab soon. Rick concluded with his personal comment that MINOS needs a long-term, dedicated magnetic field group to support the engineering effort; a list of tasks for this group was suggested. 5. Near detector Cat James summarized the discussions in the near detector working group. A new scintillator instrumentation scheme was worked out for the squashed steel geometry. All scintillator strips in the near detector will be read out from only one end. Four out of five planes in the forward section (veto, target and shower) will be instrumented only in the beam region (about 7 m^2). Fully instrumented planes (scintillator covering most of the 14 m^2 steel area) will be used for every fifth plane in the forward section and every fourth plane in the muon section. Three out of four planes in the muon section will have no scintillator. The forward section planes will not be multiplexed, but the muon section plane readout will be 4X multiplexed. The near detector simulation needs to catch up with the current design and then be used to check that this design meets physics and beam monitoring requirements. 6. Emulsion experiment Jim Hylen summarized discussions in the emulsion working group sessions. The sessions were well attended and informative, although several of the talks on the agenda were given in absentia. Reconstructions of events in the E872 prototype hybrid emulsion modules are now available and look quite good. Adam Para described a plan for an emulsion stacking and processing facility at Fermilab, and outlined a program of prototype testing to study tracking, backgrounds and aging. A conceptual design of a trigger and event localization system, based on D0 mini-drift tubes, has been worked out. A number of potential emulsion suppliers have been contacted, and plans for test beam exposures of prototype modules at Brookhaven and/or CERN were discussed. Jim reviewed Adam's long list of emulsion experiment design issues. He concluded with the observations that a 1 kton emulsion detector would cost about the same as the MINOS baseline detector but would be more complex, and is now about at the stage which the baseline design had reached three years ago. The emulsion collaboration would need to grow substantially to work out the details of the experiment, but that there were no obvious showstopper issues if costs can be kept under control. 7. Far detector installation Bill Miller outlined the topics discussed by the far installation working group, which held joint meetings with steel, scintillator and electronics working groups as well as with CNA engineers. The four plane prototype work at Fermilab will include tests of the steel rigging procedures proposed for the use at the Soudan mine shaft stations. The process to obtain State funding for the Soudan surface receiving building needs to be started soon. At this meeting, the far installation and scintillator groups agreed on a general plan for testing and handling the new wide scintillator modules at Soudan. The new scintillator module design will probably allow the MUX boxes to be moved to more convenient locations, closer to the walkways, after the July Review. Discussions with the electronics group covered electronics for radioactive source testing at Soudan, the implications of moving the MUX boxes, and possible MUX box cooling. Draft copies of the CNA Design Development Report were distributed to a number of Collaboration reviewers for comment. At Ely, the electronics and far installation groups reviewed the electrical drawings and quiet power provisions described in the report; a number of minor changes were suggested. For the July Review, CNA cost estimates will be revised to include only the baseline two supermodule case. 8. Scintillator Doug Michael summarized the activities of the scintillator working group, which involved more people and sessions than any other group at Ely. He began with a summary of changes agreed to for the July Review TDR edition. It will use the more expensive Kuraray WLS fiber, 20- and 28-strip wide modules, redesigned module end manifolds, 28-wide fiber optics connectors, and will have much less emphasis on the HPD option. He also showed the group's plans to address major issues for the July Review: Level 3 WBS managers will prepare Basis of Estimate binders; there will be a Project Manager's review of the scintillator cost and schedule on June 26; several proposals for building and operating module construction facilities at MINOS institutions will be developed; a program of talks on institutional R&D results and plans will be prepared for the review; presentations on low light yield physics effects and contingency options will also be prepared. Doug showed the scintillator system management structure which is now in place, including the names of WBS Level 3 managers. Doug summarized the results of recent scintillator R&D work on module light yields (minimum summed output now up to 4.5 pe's), clear fiber extensions, connector light losses, PMTs, WLS fibers, scintillator strip production, aging studies, module assembly and calibration. He listed the goals of the current scintillator engineering and optimization work as lowering costs, understanding the minimum light level needed to achieve physics goals, understanding vendor capabilities, preparing for production at collaborating institutions, anticipating major construction problems in advance, understanding costs and schedule issues in detail, and passing the upcoming reviews. Doug then listed the menu of scintillator optimization and engineering tasks: light yield improvement (multiplying all possible improvements gives a factor of nine!), scintillator production and aging, WLS fiber optimization, fiber connector and clear fiber development, MUX box design (including squeezed fiber tests), scintillator module design, calibration system design, production and test equipment design. Doug listed the issues which will be considered in the PMT/HPD decision, and described the current ideas about the design of a custom HPD for MINOS. He proposed a schedule of milestones for HPD and PMT studies (including both the M16 and L16 Hamamatsu tubes) and a decision process which would lead to a final choice of the MINOS photodetector in February 1999. He showed a technically driven schedule of scintillator R&D milestones which culminated with the start of scintillator module installation at Soudan in June 2000 (six months ahead of the estimated beneficial occupancy date). Doug concluded with a list of construction tasks which could be performed at collaborating institutions, including the names of institutions which have expressed an interest in each task: scintillator module construction, production of clear fiber cables with connectors, production of MUX boxes, testing of photodetectors, production of light injection system components, construction of production and test equipment, interface to the database system, and management of materials acquisition, logistics and quality control. More detailed descriptions of all of these topics can be found in Doug's transparencies in NuMI-L-384. 9. Plans for the July Director's Review Stan and Gina described the current agenda and plan for the July Director's Review. Gary Sanders and Dennis Theriot are the committee co-chairs; much of the committee is the same as for the April Director's Review. The Soudan site preparation and near and far detector installation are not covered. After overview talks by Tom Fields and Stan, four hours are devoted to the NuMI plenary talks, followed by three hours of MINOS plenary talks and three hours of parallel breakout sessions. NuMI presentations are to cover the entire Fermilab construction project since this was not reviewed in April, but the MINOS presentations are to focus on changes since the April Director's Review and responses to the comments of the April review committee. In addition, John Peoples has requested that our presentations highlight the accomplishments of R&D work at collaborating institutions, which has been partially funded by Fermilab. M. 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 meeting. Submit NuMI/MINOS TDRs to Fermilab Jul 6 (Mon) Director's Review of NuMI-MINOS Jul 13-15 (Mon-Wed) MINOS meeting at Fermilab Aug 14-16 (Fri-Sun) Submit draft NuMI-MINOS Lehman documents Sep 1 (Tue) Director's Review of NuMI-MINOS (proposed) Sep 14-15 (Mon-Tue) Submit final NuMI-MINOS Lehman documents Sep 29 (Tue) MINOS meeting at Fermilab Oct 16-17 (Fri-Sat) Lehman Baseline Review of NuMI-MINOS Oct 20-22 (Tue-Thu) Fermilab PAC meeting, MINOS presentation Oct 23-25 (Fri-Sun) MINOS meeting in London Dec 5-6 (Sat-Sun) Fermilab PAC meeting Jan 15-17 (Fri-Sun) MINOS meeting at Caltech Feb 5-6 (Fri-Sat) MINOS meeting at Fermilab Apr 9-10 (Fri-Sat) Fermilab PAC meeting May 14-16 (Fri-Sun) MINOS Week-in-the-Woods at Ely Jun 16-22 (Wed-Tue) Fermilab PAC meeting (Aspen) Jun 18-25 (Fri-Fri)