First Results from Tracker 1  Cryostat Commissioning  AFE/VLSB Firmware and Readout  Cosmic Ray Setup  Tracker Readout  Software  Trigger Timing Scan  Alignment  Light Yield  Next Steps 1M.Ellis - VC th July 2008

Cryostat Commissioning  Both cryostats cooled down very well and reached a temperature that allows all 4 cassettes to operate at 9.0 Kelvin.  The lid heater alarms and VESDA smoke detection system have been hooked up to a relay that will kill the AFE power if any of the three alarm.  An auto-dialler will call an expert (or the MOM) if any of the above alarms occur, or if either of the insulating vacua start to degrade. 2M.Ellis - VC th July 2008

AFE / VLSB Firmware  New AFE and VLSB firmware from Fermilab is being used for the readout.  An additional VLSB is providing an encoded clock signal that is fanned out to all 8 AFE boards.  The readout is operating asynchronously, with the trigger coincidence signal being vetoed by the master VLSB to only allow a trigger to be produced in the correct live windows. 3M.Ellis - VC th July 2008

Cosmic Ray Setup  The 25 waveguides were connected and the cassettes made light tight.  At the moment there is a 2 inch layer of lead under the tracker to act as a momentum filter.  The coincidence of two trigger scintillators (one above the tracker, one underneath the tracker and a layer of lead) provides the external trigger (which is a bit noisy).  Some new trigger scintillators are being prepared at Fermilab which should increase the trigger rate and the trigger efficiency. 4M.Ellis - VC th July 2008

Tracker Readout  At the moment we are using the Excel/Visual Basic DAQ developed at Fermilab.  Hideyuki is working on a Linux based AFE initialisation code.  Once that is working, we will check that the data taken looks the same and start to move to a Linux based AFE initialisation and DATE DAQ for readout. 5M.Ellis - VC th July 2008

Software  The decoding and calibration files have been committed to G4MICE and the necessary unpacking code for the current data format.  A new application – “R8CosmicTest” has been added which reconstructs the data and creates ROOT histograms and event display files for viewing using HepRApp.  All plots in this talk can be reproduced by checking out the most recent version. 6M.Ellis - VC th July 2008

Trigger Timing Scan  Need to get the delay between cosmic ray passage and AFE trigger signal correct at the level of ns.  Scan over a range of delays, take data for a day and find delay with maximum light yield. 7M.Ellis - VC th July 2008

Trigger Timing Scan - Results 8M.Ellis - VC th July 2008 Delay chosen: 862 ns Filled square – station 1 Triangle up – station 2 Triangle down – station 3 Open circle – station 4 Open square – station 5 Light Yield for each Station Average Light Yield for All 5 Stations

Alignment  The alignment started with the nominal values from the tracker design for the station spacing, central fibres, etc.  These were fed into G4MICE and triplet residuals and tracking residuals used to spot any misalignments or inconsistencies. 9M.Ellis - VC th July 2008

Triplet Internal Residuals 10M.Ellis - VC th July 2008 Stations 1 – 4 have residuals centred near 0 with no need for any alignment

Triplet Residuals – Station 5 11M.Ellis - VC th July 2008 Station 5 before adjusting the nominal values Station 5 after adjusting plane X

Station Alignment  Will check station spacing with Coordinate Measuring Machine (CMM) data, but for now assume the spacing is exactly as designed.  At high momentum (i.e. no MCS), expect residuals to have an RMS of ~ 430  m in X and ~ 497  m in Y. 12M.Ellis - VC th July 2008

Track Residuals 13M.Ellis - VC th July 2008 X – expect 430  m, see 466  m RMS Y – expect,497  m, see 549  m RMS Implies misalignments of order 100  m TRD Spec for Tracker alignment: 70  m

Light Yield  Light yield determined by plotting the distribution for each plane and each station (integrating over planes in a station) for clusters that were included in a good track.  Some features (narrow peaks) in the plots for individual planes/stations are due to overflow of the ADC.  Due to variations in the gain of the cassettes, these peaks move around as a function of plane/station. 14M.Ellis - VC th July 2008

Light Yield – All Stations 15M.Ellis - VC th July 2008 Light Yield: ~ 11 PE

Next Steps  Add another layer of lead and continue data taking at the optimum trigger delay.  Use CMM data to update station spacing and possibly transverse positions.  Study light yield and efficiency for each station and each plane, and if sufficient statistics, as a function of position on the plane. 16M.Ellis - VC th July 2008

Finally – 100 Events with 5 point Tracks: 17M.Ellis - VC th July 2008