Early Career Internal Review Upgrade and development for calorimetry for Deeply Virtual Compton Scattering Alexandre Camsonne November 18 th 2011 VI. Nuclear Physics (NP)

Early Career Internal Review Executive Summary/Abstract The structure of the nucleon is one of the main research axis at Jefferson Laboratory. General Parton Distributions (GPDs) are a generalization of the concept of Form Factor and parton distributions which are defined as limit of General Parton Distributions. The GPDs give an additional spatial dimension to our knowledge of the partons in the nucleon. The Hall A experiment was able to measure of absolute cross section for DVCS using a calorimeter associated with Flash ADCs this is the most direct measurement to access GPDs. The experience from the previous experiments showed that the background in the calorimeter was a limiting factor for resolution and luminosity. Improvement in calorimetry radiation and background hardnessness is crucial for the 12 GeV program.

Early Career Internal Review Specific Scientific Aims Continue the Lead Fluoride PbF2 effort for 12 GeV Hall A experiment Upgrade electronics to reduce effect of background on resolution Investigate possibility of use of gaseous detector as replacement of PMT to eliminate PMT aging issue due to background. Investigate sampling calorimeter using Micro Pattern Gaseous.By design this kind of detector is less sensitive to low energy background but energy resolution at JLab range should be determined an optimized. R&D useful for higher energies too. Build full size calorimeter and evaluate performance in beam and compare to PbF 2 with parasitic data taking and during Hall A DVCS experiment.

Early Career Internal Review Research Impact and Benefits Impact and benefits for Jefferson Lab Improved quality of and efficiency of data taking, for any experiment using calorimetry at 12 GeV and beyond by providing radiation hardness, low downtime and an increased in luminosity treatment of background for improved resolution in high background conditions. This will open the way to studies of low counting rate channels such as Double DVCS or J/psi production Impact and benefits for Nuclear Physics High radiation hardness calorimetry will be useful for many other experiment requiring calorimetry in hostile environment such as SOLiD program in Hall A and EIC and other high energy facilities. Impact and benefits for Office of Science Gaseous photodector can also be a cheaper alternative to PMTs which could be used in medical application. Expertise with Micromegas detectors

Early Career Internal Review Deliverables Upgrade in calorimeter infrastructure –Upgrade of current DVCS calorimeter Second Lead Fluoride calorimeter –Readout for 208 detector channels Sampling calorimeter –50 cm * 50 cm * cm –40 layers, channels High purity gas system for GEM Electronics –256 channels of Flash ADC – channels of APV25 readout for calorimeter. Can be used by other experiments

Early Career Internal Review PbF2 Calorimeter Lead fluoride calorimeter 13 x 16 = 208 blocks 39 cm x 48 cm Read out by Hamamatsu PMTs PbF2 PMT Blue curing light

Early Career Internal Review Visible GEM Stony Brook and Brookhaven Weizmann Institute Photosensitive coating GEM for electron multiplication

Early Career Internal Review Sampling calorimeter Prototype of hadron calorimeter using the Micromegas technology for Hadron Calorimeter for EIC with Annecy IN2P3 laboratory 1 m3 detector with 40 layers of iron/micromegas For DVCS –50 cm x 50 cm x cm Most cost in readout electronics

Early Career Internal Review Budget Calorimeter upgrade –60 K$ Second Lead Fluoride Calorimeter –660 K$ Sampling Calorimeter –550 K$ Total direct cost for detectors 1,280 K$ Total cost : 1,830 K$ –Funding profile Year Direct202K$234K$352K$337K$336 K$ Indirect81 K$42 K$76 K$88 K$85 K$ Total283 K$276 K$428 K$425 K$421 K$

Early Career Internal Review Resources Needed PI 50% of work charge (75 K$ year ) Additional man power to complete the project : 1 Jlab Designer for calorimeter redesign for 2 years 80 K$ for 2 years 1 postdoc, 2 PhD student by collaborating Universities Collaborators : CEA Saclay, Old Dominion University 1 professor (25 % ), Ohio University 1 professor (25 %), IPN Orsay 1 staff scientist (25 %) and 1 engineer ( 100 %) Ressources : Machine shop, detector group, electronic group, test lab, clean room

Early Career Internal Review Schedule and Milestones M : Milestone R : resultQ1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4Q1Q2Q3Q4 Electronics upgrade 72K$M Procurement PbF2 176K$ 75K 120K $ M 130K $ Block selection irradiation tests 12.5K $ M Redesign of calorimeter 40 K$ PbF2 Calorimeter complete M Test run with visible Micromegas with PbF2 50 K$ R Procure MGPD for sampling calorimeter 130K Procure sampling calorimeter lead 20 K$ Procure sampling calorimeter electronics 25K$ 50K$ 150K$ 25K$ 50K$ M Sampling Calorimeter design 50 K$ Sampling Calorimeter frame 10 K$ Sampling calorimeter complete M Sampling calorimeter parasitic beam test Procure PMTs or build gaseous photon detector M125K$ Beam in Hall A M APEX PREX DVCS 12 GeV Run I M A1n DVCS 12 GeV Run II beginning 2017 DVCS can run Test sampling calorimeter News PbF2 calorimeter complete for DVCS 12 GeV Run II