BABAR, the detector for the SLAC PEP-II asymmetric e+e- B Factory operating at the upsilon 4S resonance, was designed to allow comprehensive studies of CP-violation in B-meson decays. Charged particle tracks are measured in a multi-layer silicon vertex tracker surrounded by a cylindrical wire drift chamber. Electromagentic showers from electrons and photons are detected in an array of CsI crystals located just inside the solenoidal coil of a superconducting magnet. Muons and neutral hadrons are identified by arrays of resistive plate chambers inserted into gaps in the steel flux return of the magnet. Charged hadrons are identified by dE/dx measurements in the tracking detectors and in a ring-imaging Cherenkov detector surrounding the drift chamber. The trigger, data acquisition and data-monitoring systems, VME- and network-based, are controlled by custom-designed online software. Details of the layout and performance of the detector components and their associated electronics and software are presented.

The BABAR detector

The BaBar detector

This document describes the technical layout and the expected performance of the Straw Tube Tracker (STT), the main tracking detector of the PANDA target spectrometer. The STT encloses a Micro-Vertex-Detector (MVD) for the inner tracking and is followed in beam direction by a set of GEM stations. The tasks of the STT are the measurement of the particle momentum from the reconstructed trajectory and the measurement of the specific energy loss for a particle identification. Dedicated simulations with full analysis studies of certain proton-antiproton reactions, identified as being benchmark tests for the whole PANDA scientific program, have been performed to test the STT layout and performance. The results are presented, and the time lines to construct the STT are described.

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Technical design report for the PANDA (AntiProton Annihilations at Darmstadt) Straw Tube Tracker

In this document the PHENIX collaboration proposes a major upgrade to the PHENIX detector at the Relativistic Heavy Ion Collider. This upgrade, sPHENIX, enables an extremely rich jet and beauty quarkonia physics program addressing fundamental questions about the nature of the strongly coupled quark-gluon plasma (QGP), discovered experimentally at RHIC to be a perfect fluid. The startling dynamics of the QGP on fluid-like length scales is an emergent property of quantum chromodynamics (QCD), seemingly implicit in the Lagrangian but stubbornly hidden from view. QCD is an asymptotically free theory, but how QCD manifests as a strongly coupled fluid with specific shear viscosity near $T_C$, as low as allowed by the uncertainty principle, is as fundamental an issue as that of how confinement itself arises.

An Upgrade Proposal from the PHENIX Collaboration

The super Pioneering High Energy Nuclear Interaction eXperiment (sPHENIX) at the Relativistic Heavy Ion Collider will perform high-precision measurements of jets and heavy flavor observables for a wide selection of nuclear collision systems, elucidating the microscopic nature of strongly interacting matter ranging from nucleons to the strongly coupled quark–gluon plasma. A prototype of the sPHENIX calorimeter system was tested at the Fermilab Test Beam Facility as experiment T-1044 in the spring of 2016. The electromagnetic calorimeter (EMCal) prototype is composed of scintillating fibers embedded in a mixture of tungsten powder and epoxy. The hadronic calorimeter (HCal) prototype is composed of tilted steel plates alternating with the plastic scintillator. Results of the test beam reveal the energy resolution for electrons in the EMCal is $2.8\%\oplus 15.5\%/\sqrt {E}$ and the energy resolution for hadrons in the combined EMCal plus HCal system is $13.5\%\oplus 64.9\%/\sqrt {E}$ . These results demonstrate that the performance of the proposed calorimeter system satisfies the sPHENIX specifications.

Design and Beam Test Results for the sPHENIX Electromagnetic and Hadronic Calorimeter Prototypes

An aluminium stabilized, thin superconducting solenoid is required for the central field of 1.5 T for the BABAR detector. The winding is supported by an aluminium alloy outer cylinder, which provides hoop strength to the coil. The coil has dimensions of 3 m in diameter and 3.7 m in length. The current density is graded to meet the field uniformity requirements of /spl plusmn/2%. A hexagonal flux return, comprised of a barrel and two end doors provides the external flux path for the field. Additional material is required in the end caps to shield the flux from the beam line magnets. To accommodate the muon detectors, the barrel and end caps are segmented into 20 plates of different thickness. Special attention is given to the support of the coil and cryostat to account for seismic loading. The coil is indirectly cooled to 4.5 K using the liquid helium thermo-siphon technique and cooling channels welded to the support cylinder. Automatic cooldown and cryogen supply to the coil and its 40 K radiation shield is done by a helium liquefier/refrigerator via coaxial, return gas screened, flexible transfer lines.

The superconducting magnet for the BABAR detector of the PEP-II B Factory at SLAC

The 1.5 T superconducting solenoid is part of the BaBar detector located in the PEP-II B-Factory machine at the Stanford Linear Accelerator Center. The solenoid has a 2.8 m bore and is 3.7 m long. The two layer solenoid is wound with an aluminum stabilized conductor which is graded axially to produce a +/3% field uniformity in the tracking region. The 24 month fabrication, 3 month installation and 1 month commissioning of the solenoid were completed on time and budget. This paper summarizes the culmination of a 3 year design, fabrication and testing program of the BaBar superconducting solenoid. Critical current measurements of the superconducting strand, cable and conductor, cool-down, operation with the thermosyphon cooling, fast and slow discharges, and magnetic forces are discussed in detail.

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Design and testing of the 1.5 T superconducting solenoid for the BaBar detector at PEP-II in SLAC

The BABAR Detector, located in the PEP-II B-Factory at the Stanford Linear Accelerator Center, includes a large 1.5 Tesla superconducting solenoid, 2.8 m bore and length 3.7 m. The two layer solenoid is wound with an aluminum stabilized conductor which is graded axially to produce a +/- 3% field uniformity in the tracking region. This paper summarizes the 3 year design, fabrication and testing program of the superconducting solenoid. The work was carried out by an international collaboration between INFN, LLNL and SLAC. The coil was constructed by Ansaldo Energia. Critical current measurements of the superconducting strand, cable and conductor, cool-down, operation with the thermo-siphon cooling, fast and slow discharges, and magnetic forces are discussed in detail.

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W. Craddock

Papers

The superconducting magnet for the BABAR detector of the PEP-II B Factory at SLAC

Design and testing of the 1.5 T superconducting solenoid for the BaBar detector at PEP-II in SLAC

The BaBar superconducting coil: design, construction and test