1. |
- Ahmed, M., et al.
(författare)
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Search for the lepton-family-number nonconserving decay μ +→e +γ
- 2002
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Ingår i: Physical Review D. - : American Physical Society. - 1550-7998 .- 1550-2368. ; 65:11
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Tidskriftsartikel (refereegranskat)abstract
- The MEGA experiment, which searched for the muon- and electron-number violating decay μ +→e + γ, is described. The spectrometer system, the calibrations, the data taking procedures, the data analysis, and the sensitivity of the experiment are discussed. The most stringent upper limit on the branching ratio, B(μ + →e + γ)<1.2×10 -11 with 90% confidence, is derived from a likelihood analysis.
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2. |
- Szymanski, J. J., et al.
(författare)
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A study of the decay mu –> e gamma by the MEGA experiment
- 1996
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Ingår i: Proceedings, 9th Meeting, DPF'96, Minneapolis, USA, August 11-15, 1996. Vol. 1, 2.. ; , s. 1450-1452
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Konferensbidrag (refereegranskat)
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3. |
- Szymanski, J. J., et al.
(författare)
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MEGA : A search for the decay mu –> e gamma
- 1994
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Ingår i: Intersections between particle and nuclear physics. Proceedings, 5th Conference, St. Petersburg, USA, May 31-June 6, 1994. ; , s. 789-792
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Konferensbidrag (refereegranskat)
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4. |
- Amann, F., et al.
(författare)
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A search for murarregamma at the level of 10-13
- 1991
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Ingår i: Proceedings of the 25th International Conference on High Energy Physics. - 9810024347 ; , s. 1070-1071
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Konferensbidrag (refereegranskat)abstract
- The MEGA experiment, which is a search for the decay murarregamma with a branching ratio sensitivity of about 10-13, employs highly modular, fast detectors, state-of-the-art electronics, and a staged trigger with on-line filters. The detectors are contained in a 1.5-T solenoidal field produced by a superconducting magnet. Positrons are confined to the central region and are measured by a set of thin MWPCs. Photons are measured by one of four layers of pair spectrometers in the outer region. Most aspects of the design have been validated in engineering runs; data taking will begin in 1990 with much of the electron arm and one pair spectrometer layer installed.
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5. |
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6. |
- Cooper, M. D., et al.
(författare)
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Construction and performance of MEGA's low-mass, high-rate cylindrical MWPCs
- 1998
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576. ; 417:1, s. 24-49
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Tidskriftsartikel (refereegranskat)abstract
- A design for extremely low mass, high-resolution multiwire proportional chambers (MWPC) was achieved by the MEGA collaboration in its experiment to search for the lepton family number violating decay μ → eγ. To extend the present branching ratio limit by over an order of magnitude, these MWPCs were operated in high particle fluxes. They showed minimal effects of aging, and evidenced spatial and energy resolutions for the orbiting positrons from muon decay which were consistent with our design parameters. The unique features of these chambers, their assembly into the MEGA positron spectrometer, and their performance during the experiment are described in this paper.
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7. |
- Armijo, V., et al.
(författare)
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A fast MWPC with cathode strips and utilizing CF4-isobutane
- 1991
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier. - 0168-9002 .- 1872-9576. ; 303:2, s. 298-308
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Tidskriftsartikel (refereegranskat)abstract
- A planar wire chamber has been developed at LAMPF as a prototype for wire chambers of cylindrical configuration for electron detection in the MEGA experiment. Results form tests with the planar chamber have been used to set the geometrical parameters and predict the performance characteristics of the cylindrical chambers. The behavior of the planar chamber with CF4-isobutane gas demonstrates that 15 μm wire of 1 mm pitch is practical, that lifetimes greater than 0.045 C/cm are achievable and that gate widths of 25 ns are possible. © 1991.
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8. |
- Mischke, R. E., et al.
(författare)
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Low mass, high rate cylindrical MWPCs for the MEGA experiment
- 1990
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Konferensbidrag (refereegranskat)abstract
- The construction of MWPCs for the MEGA experiment at LAMPF are described. The chambers are cylindrical, low mass (3 {times} 10{sup {minus}4} radiation lengths), and are designed to operate at high rates (3 {times} 10{sup 4} /mm{sup 2}/s). Several novel construction techniques have been developed and custom electronics have been designed to help achieve the required performance, which corresponds to that needed at high luminosity colliders.
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9. |
- Stanislaus, S., et al.
(författare)
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Results from beam tests of MEGA's low-mass, high-rate cylindrical MWPCs
- 1992
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - 0168-9002 .- 1872-9576. ; 323:1-2, s. 198-202
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Tidskriftsartikel (refereegranskat)abstract
- One of the leading experimental projects at LAMPF has been the MEGA experiment. This is an experiment to search for the rare decay μ → eγ with a sensitivity of 10-13. A prime component of this project has been the design and construction of high-rate, low-mass MWPCs for the tracking of positrons from muon decay. With rate capabilities of 2 × 104 e+/mm2/s and a thickness of 3 × 10-4 radiation lengths, these chambers are state-of-the-art cylindrical MWPCs. Cylindrical chambers of this size (0.9 m2) and thinness have never been previously constructed. The MEGA project at LAMPF has recently succeeded in building chambers with these necessary performance characteristics as demonstrated by data taken from muon decays, cosmic rays, and sources. © 1992.
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