The ILD ECAL Jan th Paris Satoru Uozumi (Kyungpook Natl. Univ.) for the ILD ECAL group Contents :

The ILD ECAL Finely granular PFA calorimeter with tungsten absorber Cell-size in baseline design ~ 5 x 5 mm 2, num. of cells 3~10M in total Necessary to achieve less dead space, low production cost Candidate technologies : Silicon-tungsten Scintillator-tungsten MAPS/DECAL Jet energy resolution by M. Thomson Barrel: 5 octogonal wheels R min = 1808 mm; R max = 2220 mm Width = 940 mm End-caps: 4 quarters ∅ min = 800 mm

Silicon-tungsten ECAL Structure – 20 layers of 2.1 mm (0.6X 0 ) W + 9 layers of 4.2mm (1.2X 0 )W – 5x5 mm 2 granularity of Si ~ 108 M cells in total 10x10 mm 2 physics prototype tested in beam – FLC_PHY4=3 chips with analog readout – Energy resolution measured in test beam ~ 16.6%/√E(GeV) ⊕ 1.1%with S/N ratio of 7.5 for a mip signal – CERN 2006, 2007 – FNAL 2008, 2009 Working principle has been proven by the sort of prototype beam tests.

Silicon-tungsten R&D status Results of 2006 beam CERN with 2/3 equipped SiW-ECAL – Highly linear response – Good energy / spatial resolution Analysis of 2007 and 2008 beam test data with fully equipped SiW-ECAL currently ongoing. SiW-ECAL AHCAL TCMT

Silicon-W issues for future R&D Other R&D issues : power pulsing of FE electronics (common problem with SciW) Si sensors price (3000 m 2 ) currently 10 Euro/cm 2 Dips observed in ECAL response by inter-wafer gaps. Correction works, but dips cannnot fully recovered.

Scintillator-tungsten ECAL Scintillator strip structure aiming to have virtual crossing cell Physics prototype built in 2008 – 30 layers of 72 strips – Full MPPC readout

Physics prototype tested in 2008 / 2009 at FNAL Scintillator-tungsten R&D status

Scintillator-ECAL strip clustering (with Mokka +Pandora PFA) Strip clustering with the scntillator-ECAL to make virtual cells from the strip geometry. Current simulation study indicates that the JER doesn’t depend on the shape of the scintillator, but just changes with its area. Due to the two-hold unbiguity ? If so, adding small-pixel layer will resolve it.

MAPS (DECAL) option Ultimate Spatial resolution – 50x50 μm 2 pixels – TERA Pixel detector TPAC readout chip v1 = 168 x 168 pixels; 79.4 mm 2 Expected resolution (pixel counting) 13%/√E(GeV) ⊕ 1% Status: – successful CERN TB of 6 sensors summer 2009 – New SPiDeR collaboration – Physics prototype planned for 2012 Critical points – integration, Power consumption, services, price,... – Funding issue for further R&D

Idea of combined ECAL A lot of discussion has been done to form the “Unified ILD ECAL” during January ‘10. One optimal solution is found to be a “hybrid-type ECAL” with silicon pixels, pads and scintillator-strips. – Smaller cells in pre-shower and shower-max region. – Scintillator-strip covers the EM shower after the maximum. – Cost-effective – No two-hold ambiguity for the strip clustering with silicon sensors – Can use established silicon and scintillator technologies. – Need extensive simulation study to determine number of Si/Sci layers, combined clustering and the PFA. Mokka simulation of the hybrid-type ECAL is under preparation. Cell size

Question from IDAG Each validated detector group will produce a detailed baseline design by To this end the following steps are planned. 1.Demonstrate proof principle on critical components. – When there are options, at least one option for each subsystem will reach a level of maturity which verifies feasibility. 2.Define a feasible baseline design. – While a baseline will be specified, options may also be considered. We consider the “baseline” as the “basic configuration”, such as cell-size, number of layers, amount of materials, but doesn’t include specific detector technology. (or put Silicon-Scintillator hybrid ECAL as a candidate.) 3.Complete basic mechanical integration of the baseline design accounting for insensitive zones such as the beam holes, support structure, cables, gaps or inner detector material. 4.Develop a realistic simulation model of the baseline design, including the identified faults and limitations. 5.Develop a push-pull mechanism, working out the movement procedure, time scale, alignment and calibration schemes in cooperation with relevant groups. 6.Develop a realistic concept of integration with the accelerator including the IR design. 7.Simulate and analyze updated benchmark reactions with the realistic detector model. Include the impact of detector dead zones and updated background conditions. 8.Simulate and study some reactions at 1 TeV, including realistic higher energy backgrounds, demonstrating the detector performance.

Milestones to prove Si-Sc-W ECAL feasibility by end 2012 Technical - Demonstrate power pulsing of FE chips (in common with other *ROC chips) (by mid 2011) Power pulse in magnetic field (by mid 2012) - design and produce thin PCB for scintillator/MPPC layers (by mid 2011) Simulation (all by mid 2010) - implement dead zones of scintillator - implement non-uniformity of strip response - update ILD Si simulation to same level as CALICE SiW testbeam simulation - realistic end-of-slab instrumentation (fractional Si detection elements) Reconstruction - reconstruction of strip and mixed geometries (by end 2010) - study of single particle energy resolution and PFA performance in different scenarios (by end 2011)

Waiting for input… Milestones to prove MAPS feasibility by end 2012

The EUDET ECAL prototype

The EUDET prototype Silicon module Scintillator module The EUDET alveolar structure can accommodate both Si / Sci ECAL modules. Discussion underway to make compatible structure.

Electronics on PCB Chip for ECAL = “SKIROC” Presently have SPIROC2 chip (for AHCAL), running in “SKIROC mode” SKIROC2 chip will be submitted for manufacture this month Many tests needed Tests of power pulsing have started - looks encouraging

Plans for the EUDET prototype Alveolar structure by mid-2010 H-type support structure by end-2010 Test DAQ FE will be available ~ spring 2011 Future beam test – SiW module : CERN ? – Test with several ScECAL modules ~ 2012? – Combined test with HCAL technical prototype ~ after 2012.

Summary Technologies and feasibility for the ILD ECAL is being established (in CALICE collaboration). – Several beam test has been done with SiW and SciW ECAL prototypes during – MAPS sucessfully operated 6 sensors in – Realistic simulation study with PandoraPFA is ongoing. Now those technologies are being unified to one ILD ECAL with silicon and scintillator layers. – Very fresh idea, extensive simulation study will be necessary. Still a lot of works need be addressed to finish homeworks given by IDAG. EUDET technical prototype will be the next stage of the hardware R&D. – Several tests will be running from 2010 until the detector TDR.