Status of Muon Collider Research and Development and Future Plans

The status of the research on muon colliders is discussed and plans are outlined for future theoretical and experimental studies. Besides continued work on the parameters of a 3-4 and 0.5 TeV center-of-mass (CoM) energy collider, many studies are now concentrating on a machine near 0.1 TeV (CoM) that could be a factory for the s-channel production of Higgs particles. We discuss the research on the various components in such muon colliders, starting from the proton accelerator needed to generate pions from a heavy-Z target and proceeding through the phase rotation and decay ($\pi \to \mu \nu_{\mu}$) channel, muon cooling, acceleration, storage in a collider ring and the collider detector. We also present theoretical and experimental R & D plans for the next several years that should lead to a better understanding of the design and feasibility issues for all of the components. This report is an update of the progress on the R & D since the Feasibility Study of Muon Colliders presented at the Snowmass'96 Workshop [R. B. Palmer, A. Sessler and A. Tollestrup, Proceedings of the 1996 DPF/DPB Summer Study on High-Energy Physics (Stanford Linear Accelerator Center, Menlo Park, CA, 1997)].Comment: 95 pages, 75 figures. Submitted to Physical Review Special Topics, Accelerators and Beam

Development and Study of Technological Visual Programming of Logic Control Problems

The approach to logic control programming using a technological language was described. It is based on the use of a tabular cyclogram directly as a programming language. It was shown that using a cyclogram, it is possible to describe the complete algorithm of logic control of industrial equipment, and with its use to generate automatically a program code in standard languages of programming of industrial controllers. This approach will make it possible to involve engineers-technologists, who are the most competent experts in the field of automated process, in the process of developing and debugging of control programs.The benefits of technological visual programming in comparison with the conventional approach to control programming were described. The requirements for the necessary structure of a specialized programming environment with the use of a tabular language of technological cyclograms were stated. During experiments in the developed environment, the authors described in the cyclogram language the algorithm of controlling a portal industrial robot, by which a specialized translator automatically generated the complete program code in the language of IEC 61131-3 standard for PLC microprocessor. In addition, within the proposed approach, the authors described the possibility to generate automatically a complete description of a logical controlling automatic machine of increased reliability in HDL-language using the same cyclogram and the template.Technological visual programming makes it possible to involve engineers-technologists directly in the process of control programming, which decreases labor consumption of developing control systems and enhances the quality of a program code. The technological cyclogram itself can be widely used by various specialists at the stages of launch-adjusting operations, maintenance and modernization of control systems, and as technical documentation during the operational phas

To the origin of Icelandic rhyolites: insights from partially melted leucocratic xenoliths

International audienceWe have studied glass-bearing leucocratic (granitic to Qz-monzonitic) crustal xenoliths from the Tindfjöll Pleistocene volcanic complex, SW Iceland. The xenoliths consist of strongly resorbed relicts of anorthitic plagioclase, K-rich feldspar and rounded quartz in colorless through pale to dark-brown interstitial glass. Spongy clinopyroxene and/or rounded or elongated crystals of orthopyroxene are in subordinate amount. Magnetite, ilmenite, zircon, apatite, allanite and/or chevkinite are accessory minerals. The xenoliths more likely are relicts of earlier-formed, partially melted Si-rich rocks or quartz–feldspar-rich crystal segregations, which suffered latter interaction with hotter and more primitive magma(s). Icelandic lavas are typically low in δ 18O compared to mantle-derived, “MORB”-like rocks (~5.6 ± 0.2 ‰), likely due to their interaction with, or contamination by, the upper-crustal rocks affected by rain and glacial melt waters. Surprisingly, many quartz and feldspar crystals and associated colorless to light-colored interstitial glasses of the studied xenoliths are not low but high in δ 18O (5.1–7.2 ‰, excluding three dark-brown glasses of 4–5 ‰). The xenoliths contain abundant, low- to high-δ 18O (2.4–6.3 ‰) young zircons (U–Pb age 0.2–0.27 ± 0.03 Ma; U–Th age 0.16 ± 0.07 Ma), most of them in oxygen isotope equilibrium with interstitial glasses. The δ 18O values >5.6 ‰ recorded in the coexisting zircon, quartz, feldspar and colorless interstitial glass suggest crystallization from melts produced by fusion of crustal rocks altered by seawater, also reflecting multiple melting and crystallization events. This suggests that “normal”-δ 18O silicic magmas may not be ultimately produced by crystallization of mafic, basaltic magmas. Instead, our new single-crystal laser fluorination and ion microprobe O-isotope data suggest addition of diverse partial crustal melts, probably originated from variously altered and preconditioned crust

Recent progress in neutrino factory and muon collider research within the Muon collaboration

We describe the status of our effort to realize a first neutrino factory and the progress made in understanding the problems associated with the collection and cooling of muons towards that end. We summarize the physics that can be done with neutrino factories as well as with intense cold beams of muons. The physics potential of muon colliders is reviewed, both as Higgs Factories and compact high energy lepton colliders. The status and timescale of our research and development effort is reviewed as well as the latest designs in cooling channels including the promise of ring coolers in achieving longitudinal and transverse cooling simultaneously. We detail the efforts being made to mount an international cooling experiment to demonstrate the ionization cooling of muons