40125877
Modular Test Facility for HTS Insert Coils
The final beam cooling stages of a Muon Collider may require DC solenoid magnets with magnetic fields in the range of 40-50 T. In this paper we will present a modular test facility developed to investigate very high fields using double pancake coils made of commercially available 2G HTS materials. The conductor performance is presented, together with magnetic calculations and an evaluation of Lorentz forces distribution in the coils when inserted in an outer solenoid. Finally, results from tests in nitrogen and helium of a double pancake coil are presented up to an external magnetic field of 14 T.
6125992
Design of a Probe for Strain Sensitivity Studies of Critical Current Densities in Superconducting Wires
The critical current density of brittle superconducting wires used in high field magnets is very sensitive to axial strain. An accurate measurement of this strain dependence at various magnetic fields and temperatures is critical for magnet design and operation. A number of methods and techniques have been used, which generally fall into either the monotonic axial loading or bending spring techniques. The design of a variable-temperature probe to perform strain sensitivity measurements in Helium of both LTS and HTS wires is herein described. The sample is wound and soldered onto a helical Walters' spring device, which is fixed at one end and subjected to a torque at the free end. Both Ti-6Al-4V and CuBe were used as materials for the Walters' spring. Two concentric copper tubes act dually as 2000 A current and 60 Nm torque carriers. The torque is generated via a worm-gear setup and transmitted to the sample through the inner tube and spring assembly.
123519490
BSCCO-2212 Wire and Cable Studies
BSCCO-2212 round wires and cables are being studied for possible use in very high field magnets (>; 25 T) within the multi-Lab Very High Field Superconducting Magnet Collaboration (VHFSMC). Billets produced by Oxford Superconducting Technology were used to make Rutherford-type cables of various geometries. The effect of the cable parameters was measured on the extracted strand performance and deformation. Transport properties were measured at 4.2 K in fields up to 14 T for the extracted strands across the edges, and compared with as-received round wire. The same wire used in the cables was also deformed by flat rolling to reproduce the deformation seen by the round strand when formed into a Rutherford cable. After heat treatment, rolled samples were characterized for transport properties and results compared to those obtained for strands extracted from the cables. Finally cables were tested at 4.2 K and self-field using a superconducting transformer and results compared to those of the extracted strands.
137403613
Design of a Probe for Strain Sensitivity Studies of Critical Current Densities in SC Wires and Tapes
The design of a variable-temperature probe used to perform strain sensitivity measurements on LTS wires and HTS wires and tapes is described. The measurements are intended to be performed at liquid helium temperatures (4.2 K). The wire or tape to be measured is wound and soldered on to a helical spring device, which is fixed at one end and subjected to a torque at the free end. The design goal is to be able to achieve {+-} 0.8 % strain in the wire and tape. The probe is designed to carry a current of 2000A.
117666088
Measurement of the CKM Angles alpha and gamma at the BaBar Experiment
We present recent measurements of the CKM angles alpha and gamma using data collected by the BaBar detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the Stanford Linear Accelerator Center. In addition to constraints on alpha from the decays B0 {yields} {pi}{sup +}{pi}{sup -}, B0 {yields} {rho}{sup +} {pi}{sup -} and B0 {yields} {rho}{sup +}{rho}{sup -}, we also report the first measurement of time-dependent CP asymmetries in the decay B0 {yields} a1{sup +}(1260) {pi}{sup -}. We present measurements of gamma in B+ {yields} D(*)0 K+ decays using a Dalitz analysis in the modes D{sup 0} {yields} Ks {pi}{sup +}{pi}{sup -} and D{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}. We present recent measurements of the CKM angles alpha and gamma using data collected by the BaBar detector at the PEP-II asymmetric-energy e{sup +}e{sup -} collider at the Stanford Linear Accelerator Center. In addition to constraints on alpha from the decays B0 -> {pi}{sup +}{pi}{sup -}, B0 {yields} {rho}{sup +} {pi}{sup -} and B0 {yields} {rho}{sup +}{rho}{sup -}, we also report the first measurement of time-dependent CP asymmetries in the decay B0 {yields} a1{sup +}(1260) {pi}{sup -}. We present measurements of gamma in B{sup +} {yields} D(*)0 K+ decays usingmore » a Dalitz analysis in the modes D{sup 0} {yields} Ks {pi}{sup +}{pi}{sup -} and D{sup 0} {yields} {pi}{sup +}{pi}{sup -}{pi}{sup 0}.« less
118793567
Hadronic B decays at BaBar and Belle
The authors review recent results of the BABAR and Belle Collaborations on the {alpha} and {gamma} angles of the unitarity triangle, on the B {yields} K{pi}{pi} Dalitz-plot analyses, and on the searches for baryonic B decays and for B {yields} D{bar D} decays.