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12 GeV Updates

20 January 2016

Power-testing of the Super High Momentum Spectrometer Horizontal Bend (HB) magnet has resumed after engineers implemented further modifications to improve the response time of the power supply's quench-detection circuitry. When this magnet reaches the current required for 11 GeV/c operation, its magnetic field will be mapped, and the magnet construction contract with Michigan State University will be complete.

The SHMS dipole magnet assembly has progressed to the point that the coil, in its helium vessel, is now surrounded by the cylindrical outer insulation, thermal shield and vacuum vessel. The weight of the coil is now permanently held by the outer vessel rather than by temporary tooling. The full assembly is more than thirteen feet long and five feet in diameter. The inner thermal shield was damaged during insertion, so magnetic-field mapping will proceed while the repairs are made to the shield. In Hall C, the huge iron yoke which will contain the dipole magnet has been leveled and opened. It is now ready and waiting for delivery of the magnet.

13 January 2016

12 GeV Hall B: Non-Magnet Update
The first article is expected to arrive soon for the remaining fast electronic modules, the crate trigger processors, needed to complete the data acquisition and triggering systems for Hall B. The installation and check-out of the balance of the VXS crates and controllers together with the fiber optic networks for data and trigger data transmission is wrapping up in the hall. The construction of the upstream support structure for the Central Time of-Flight (CTOF) for the CLAS12 spectrometer has been completed, as has fabrication of most parts for its light monitoring system and of its transport crates. Refurbishment of the last of the six sectors of the Low Threshold Cerenkov Counter (LTCC) is nearly complete, with the windows being attached, after which pressure and leak tests remain. Installation of the LTCC and the Forward Time of Flight panel 2 sectors is planned for February 2016, which will complete the Forward Carriage part of CLAS12.

6 January 2016

Hall B is prepping for the installation of the Torus magnet support legs. Up to this point, the Torus assembly has been taking place with the Torus on a "spit." This allowed for rotation of the magnet, which increased efficiency and safety during this phase of construction. The legs are the permanent support and will be installed in the near future. Hall C continues incremental testing and measurements of the horizontal bend (HB) magnet. This activity is part of the final acceptance tests of this superconducting magnet.