CMS HCAL Meeting, FIT, February 2002 Alvin Laasanen and Virgil Barnes, Purdue University 1 SOURCE CALIBRATION SOURCE CALIBRATION Status of Radioactive Source Calibration Systems for CMS HCAL Alvin Laasanen Virgil Barnes Purdue University CMS HCAL Meeting, FIT, February 2002

CMS HCAL Meeting, FIT, February 2002 Alvin Laasanen and Virgil Barnes, Purdue University 2 HB, HE SOURCE CALIBRATION HB Air-Motor Source Driver As tested at the Minnesota 4 Tesla MRI facility

CMS HCAL Meeting, FIT, February 2002 Alvin Laasanen and Virgil Barnes, Purdue University 3 HB, HE SOURCE CALIBRATION HB Air-Motor Source Driver About to enter the Minnesota 4 Tesla magnet

CMS HCAL Meeting, FIT, February 2002 Alvin Laasanen and Virgil Barnes, Purdue University 4 HB, HE SOURCE CALIBRATION Source Driver fully inserted Minnesota 4 Tesla MRI magnet

CMS HCAL Meeting, FIT, February 2002 Alvin Laasanen and Virgil Barnes, Purdue University 5 HB, HE SOURCE CALIBRATION Status of permanent source drivers: An air-powered HB driver was tested at 1.5 Tesla in a Lafayette MRI facility, and made ready for final high-field testing (replace magnetic screws, replace magnetic microswitch springs with phosphor bronze ones, etc.) A highly successful 4 T test was done at Minnesota on December 14, Motors work satisfactorily when aligned within ~5 o of the field direction; degradation in speed is gradual with misalignment. Will try for best alignment to reduce wear, but there seems to be good tolerance on installation orientation. All other components function as intended (piezo-electric air valves, microswitches, rotary encoders, and air-piloted valves, in particular). Indexing, and wire extension/retraction into long multiply- bent tubes, all functioned well.

CMS HCAL Meeting, FIT, February 2002 Alvin Laasanen and Virgil Barnes, Purdue University 6 HB, HE SOURCE CALIBRATION Permanent source drivers, contd.: Orientation of essential components is the same for HE. The control box and the two position counters worked when brought into 1 kiloGauss field, but the transformer hummed and vibrated rather heavily -- advisable not to run it long-term in such a high field. MRI magnets are always on. Insertion of the driver proved tricky due to large field gradients and associated forces and torques. At Minnesota we estimated over 100 pounds of force on the driver, while it was in the fringe field region. It was necessary to bolt the driver to the sliding table. These large translational forces will not be encountered in the HB and HE CMS installations, since the drivers will be mounted in ~homogeneous field regions. An irreducible minium of just under 1 pound of ferromagnetic material is in each air driver. OK’d by CERN management.

CMS HCAL Meeting, FIT, February 2002 Alvin Laasanen and Virgil Barnes, Purdue University 7 HB, HE SOURCE CALIBRATION Permanent source drivers, contd.: Parts acquisition for 10 air drivers (HB and HE total) is being initiated. The order will include ample spares of special items such as vane motors, which will need periodic replacement or refurbishment; and empty source wires, which will be needed when the first round of Co-60 seeds have become too weak. We are working on final specifications of information needed for integration issues, especially for HE.

CMS HCAL Meeting, FIT, February 2002 Alvin Laasanen and Virgil Barnes, Purdue University 8 HB, HE SOURCE CALIBRATION Plastic extension tubes for HB+ are at CERN. Christophe Jonckx is installing them, and optical cables, for the source-testing QC/QA and wedge commissioning in Bldg. 186, under Laza’s supervision Serguei Sergueev plans to meet with Alexei Sedov at Fermilab in February to adapt CDF multi- driver control and QIE-based source DAQ software for CMS summer 2002 test beam work.

CMS HCAL Meeting, FIT, February 2002 Alvin Laasanen and Virgil Barnes, Purdue University 9 HF SOURCE CALIBRATION Mechanical system is well defined. Ianos Schmidt is overseeing assembly of HF prototype using standard 18-gauge source tubes. Two CDF-style source drivers are complete; two more are under construction. Drivers are at Iowa, Texas Tech. Bldg 186 drivers are available for HF use as well as HB, HE use CERN-safety-acceptable type for the electrical control cables needs to be chosen, and the cable lengths need to be defined.

CMS HCAL Meeting, FIT, February 2002 Alvin Laasanen and Virgil Barnes, Purdue University 10 HF SOURCE CALIBRATION Labeling convention for HF plastic source tubes is needed, so that source driver index channels correspond to well-known locations in the calorimeter. Suggest that HF acquire a Kroy label-making machine and a supply of the printable shrink tubing (from Hanover Technical Sales, tel ) Purdue will supply 250 m of plastic tubing for summer test. Will eventually order 3.1 km of plastic tubing for HF, plus enough for all HE tubes and HB permanent extension tubes. Ianos is working on conduit design for the tube bundles.