FSC Status and Plans Pavel Semenov IHEP, Protvino on behalf of the IHEP PANDA group PANDA Russia workshop, ITEP 27 April 2010

Pavel Semenov, PANDA Russia Workshop, ITEP2 Outline FSC position and function FSC mechanical structure FSC photodetectors and monitoring system FSC prototypes studies results review FSC software activity Summary

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP3 Forward Shashlyk Calorimeter EMC at PANDA detector

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP4 Fast MC (photons energy distribution) All photons energy over photons at the Shashlyk aperture (color curves) from interactions with 5 and 15 GeV/c beam

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP5 Charmonium study, 6.27 GeV/c beam Energy of photons from charmonium decays going to FSC is relatively small, registration threshold should be similar to EMC

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP6 Shashlyk cell structure 380 layers of 0.3-mm lead and 1.5-mm scintillator, total length 680 mm Transverse size 55x55 mm 2 Light collection: 36 fibers BCF-91A (  1.0 mm) PMT as a photodetector LED for each supermodule as a light monitoring system + one optical fiber for each PMT to monitor gain?

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP7 FSC mechanical support Frame consists of two non-symmetrical parts Maintenance without beam pipe removal

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP8 Detector maintenance position FEE crates can be placed on the support frame sides All the cables on the back side, heat load?

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP9 Detector assembly procedure Removable beam for a time of half-part detector assembly

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP10 CW control and monitoring system CW multipliers for Hamamtsu R5800 and R7899 were tested during prototype studies. Multiplier require only few wires (SPI lines, +/- 6V and 100V power). An amplifier or a shaper can be easily added. CW control unit (up to 64 channels) was developed for the shashlyk prototype testbeam (based on microcontroller to program each channel HV by SPI protocol, monitoring of voltages and currents by on-chip ADC, remote control… ) LED driver to inject light into each of the 16 supermodules showed good long term stability during test beam run. To monitor PMT gain we will probably use one additional optical fiber for each PMT and one powerful LED for a part of the calorimeter. Combination of the two systems into one block provides a smart node to test photodetectors and shashlyk part of the DAQ.

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP11 Shashlyk supermodule structure A hole for the monitoring system LED One additional fiber for each PMT to monitor gain can be used

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP12 Photodetector selection The goal was to test several PMT’s types (noise, dyn.range, rate effect, signal width, quantum eff.) Now we are in the process of testing samples from Hamamatsu and ElectronTubes (Photonis “temporarily” doesn’t produce PMTs) R1925 looks attractive (like R7899 but more compact, only 43 mm and green enhanced) ETL 9085B – compact, good stability, but expensive

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP13 Cosmic muon test stand measurements To study PMT spectrum and WLS fiber spectrum match with cosmic muons Horizontal and vertical position of the Shashlyk module (MIP ~1:10) ETL R R Cosmic muons spectrum (horizontal position of the Shashlyk module)

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP14 Testbeam setup DC1 M14DC2 DC3 DC4 ECAL Beam Spectrometer consisted of 4 drift chamber stations and a magnet to measure beam particle momentum precisely Calorimeter prototype Al target at 1.5m and 3 m before the prototype S1S2S3 St Target SASA

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP15 Prototype resolution measurements (55х55 mm 2 ) σE /E = 5.6/E  2.4/√E  1.3 [%] σE /E = 3.5/E  2.8/√E  1.3 [%] (big cell) Position resolution For 55х55 cell at 19 GeV: Cell center 3 mm (6 mm for big cell), Cell edge 1.5 mm For both cell sizes

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP16 Energy deposition non-uniformity Fiber positions Non-uniformities in the order of 1% at the fiber positions because of Cherenkov light in the fiber

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP17 π 0 reconstruction results for 1.5 m Shower profile fit ( to resolve overlapping showers), Charged hadrons removed (drift chamber), Rough calorimeter calibration π GeV, σ m 12.5 MeV

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP18 Summary and plans Mechanical design of the FSC support frame is almost ready. Plans to calculate mechanical stress distribution and temperature fields to design appropriate heat removal system Photodetector selection with cosmic muons test stand is under way, Hamamatsu R7899 is a most probable candidate. PMT HV bases Cocroft-Wolton type were used for testbeam measurements. Shashlyk prototypes testbeam results show good performance with charge integrating ADC. Plans to study prototype with sampling ADC readout during December 2010 testbeam run. Go to MAMI in 2011 to test low energy detection threshold? IHEP irradiation facility to study shashlyk radiation hardness is almost ready. FCS code in the PandaRoot frame will be ready soon. Plans to use it for simulation required for FSC TDR.

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP19 Backup slides

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP20 Shashlyk photodetectors position

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP21 Time between energy depositions (one cell) Near pipeDetector vertical edge

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP22 Prototype testbeam setup

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP23 3 meter gamma-gamma mass spectrum Neutral pions energy range 3-10 GeV FWHM 40 MeV

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP24 Registered neutral pions energies at 3 m target position

27 April 2010Pavel Semenov, PANDA Russia Workshop, ITEP m target position