Six-dimensional ionization cooling of muons is essential for muon colliders and possibly beneficial for neutrino factories. An experiment to demonstrate six-dimensional ionization cooling using practical apparatus is presented. It exploits recent innovative ideas that may lead to six-dimensional muon-cooling channels with emittance reduction approaching that needed for high-luminosity muon coll...

in high-energy photon interactions with a nucleus A, as recently suggested in [7] (slide 23). Of course, muon-pair production by this process is suppressed relative to electron-positron pair production by the ratio (me/mμ) 2 ≈ 1/40, 000, so there is an issue of the efficiency of muon production via reaction (1). The Bethe-Heitler process (1) is further suppressed near threshold, so it would be ...

The CMS experiment designed for Large Hadron Collider is brieey described. An idea of a muon trigger based on RPC is presented. This talk focuses on the requirements on RPC as the trigger detectors for the CMS. We discuss the required chamber's parformance and segmentation. Current design of the system fulllling these requirements is presented. Its expected trigger performances are given. The a...

An electron neutrino can have the quantum phase of an electron, i.e. share its internal clock, if the neutrino takes a path in space-time that is not in the direction of its energy-momentum. Each flavor neutrino would then have a different internal clock; a muon neutrino would have a muon clock and a tau neutrino would have a tau clock. Perhaps surprisingly, there is some evidence suggesting ne...

Muon colliders offer special opportunities to discover and study new physics. With the high intensity source of muons at the front end, orders of magnitude improvements would be realized in searches for rare muon processes, in deep inelastic muon and neutrino scattering experiments, and in long-baseline neutrino oscillation experiments. At a 100 to 500 GeV muon collider, neutral Higgs boson (or...

The power in the charged muon decay products, deposited per unit distance, depends on the muon energy only through the relativistic factor . For a typical neutrino factory it is about one Watt/m, multiplied by the number of passes through a particular component. The power is highest in the muon decay ring, where the muon lifetime cooresponds to about 150 turns. The electrons or positrons from m...

As a step in a larger program of muon cooling R&D, we propose to study ionization cooling of 170-MeV/c muons in LH2 and LiH absorbers inside a 2-2.5 T solenoid magnet but without rf acceleration (“minicooling”). The required flux of muons is small, such that only one muon is in the apparatus at a time; the desired muon bunch will be reconstructed offline via software. This study will validate t...

We analyze muon decay using the most general local, derivative-free, Lorentz-invariant, leptonnumber-nonconserving interactions. We show that, neglecting neutrino masses, there is a one-toone correspondence between the coupling constants in the lepton-number-conserving case and combinations of coupling constants in the lepton-number-violating case; i.e., it is not possible, even in principle, t...

Fractionalization-the breaking up of an apparently indivisible microscopic degree of freedom-is one of the most counterintuitive phenomena in many-body physics. Here we study its most fundamental manifestation in spin ice, the only known fractionalized magnetic compound in 3D: we directly visualize the 1/r(2) magnetic Coulomb field of monopoles that emerge as the atomic magnetic dipoles fractio...