General EEEMCal Meeting Summary 4/15/22

PARTICPANTS: Sasha, Irina, Renee, Rosi, Tanja, Carlos, Vladimir

REVIEW STATUS OF EEEMCAL

• From R&D Plan: For CY 2021/22 there is a near term need for research in the following four areas:

• Support structure and resolution: the impact of the mechanical structure and module geometry on the detector performance has to be defined. This will form the basis for concept/design for the EMCal frame including temperature/motion control and light monitoring/curing systems.
• Scintillator material performance: scintillator material has to be characterized and its performance as EMCal detector verified. These efforts will form the basis for active materials for the EMCal and process design verification to scale up.
• Photodetector and electronics: the constraints and requirements for the readout of the EMCal have to be documented and photodetector and microelectronics solutions have to be developed.
• Software: Simulations, algorithms, and an artificial intelligence framework for design optimization have to be developed. These efforts will provide the framework for detector design.

SUPPORT STRUCTURE

• Design of the EEEMCAL being updated to the recommended geometry of ECCE (i.e. smaller size and PWO only). To do that, need the step file of the "dirc frame" in the case of ECCE.

• PM/MIT finished various versions of the support for the barrel EMCal and inwards. Expect the various documents/slides/calculations to be posted somewhere soon

• This does show that there is no substantial space for any iHCAL here as we need cross bars/links etc. in this support frame for engineering strength

• Ongoing work to import the information and update the CAD/support frame (including hpDIRC holder), and pass on for other optimizations.

• Discussion about options to increase the pseudorapidity coverage - knowing the position and the size of the beampipe flange is crucial.

It is possible to gain some flange space by increasing the bolt pattern (more and smaller bolts for the same strength but less space needed) as one typically does for high-field magnets. Rolf and Walt looked conceptually at this at the time and found that it is possible, but did not go beyond yet. For the path forward they would need to go to an assumed bolt pattern scaling from a standard flange and give the reduced dimensions. It would be a custom-made flange, but that is pretty common.

• Walt/Rolf will update on the exact flange size of the beam pipe to update the E&D of the backward EMCal, to both change for all-crystal and start looking at an inner calorimeter
• Gain in pseudorapidity would be from eta = -3.4 to eta = -3.7

• Other ongoing efforts related to EEEMCAL :

• Tanja/Elke/Rolf to check the electron detection acceptance folding in also that the DIRC bars need to be in the middle, and optimize longitudinal positions, etc.
• PM/MIT to look in more detail at the barrel EMCal PANDA design from the files they nicely provided as we need to think how to integrate that and do maintenance, etc.

• Action items:

• Check impact of radiation from beampipe on crystals close to beampipe when rapidity is increased, e.g., beam gas etc. - simulation framework in principle available (Detector 1 Joint WG)
• Update EEEMCAL design to ECCE geometry when support frame step file becomes available
• Further develop option for increasing the pseudorapidity coverage folding in information on flange

RADIATOR AND READOUT

• PWO crystals specifications being developed - no major changes expected

• Prototype tests with crystals and SciGlass

• DESY: led by MIT - focus is on SRO
• JLAB: led by CUA - focus on 1) crystal with SiPM readout, 2) SciGlass with SiPM readout
• AANL: construction of a prototype ongoing

• Prototype Crystals+SiPM readout

• Crytur-USA is developing the next generation prototype with 16 SiPM/block of Hamamatsu 10um SiPM and 3mm x 3mm device size

• 2021 version was cooled passively, which was found not to be sufficient to compensate the generated heat
• one option being investigated is to use different electronics components, but still have passive cooling
• another option might be active cooling - chiller, N2 gas
• A chiller might be availabel in Hall D, getting N2 into Hall D seems more difficult

• CUA has available a prototype with

• crystal+SiPM (25 um) and
• developed prototypes for testing SciGlass + SiPM
• new idea: test 4x4 arrays developed by Hamamatsu - current limitation: arrays are provided only for 50um pixel size at the moment
• communicating with Hamamatsu about options for 4x4 arrays for 10um SiPM would be very beneficial

• AANL group has been constructing a PWO prototype

• procurement delays with Hamamatsu SiPMs

• Action items:

• find out specifications of the chiller in Hall D
• try to set up a meeting with Hamamatsu about possibility for arrays with smaller SiPMs

SIMULATIONS

• Simulation framework exists for EEEMCAL from proposal development

• discussions ongoing about reconciliation calorimeter performance and physics

• Initial discussion about optimization of barrel and endcap calorimeter with AI-assist

• initial thought was for electron dectection, but possibly can be extended to hadron side

• Action item:

• further discuss AI-assisted calorimeter optimization

NEXT MEETING: FRIDAY 13 MAY AT 8:00 AM ET