Construction and test of a modular GEM for

Construction and test of a modular GEM for EIC Matthew Bomberger, Jacob Chesslo, Noah Pitts, Akshath Wikramanayake, Marcus Hohlmann High Energy Physics Laboratory A, Florida Tech Florida Academy of Sciences 2019

Electron Ion Collider (EIC) – What is it? e. RHIC Schematic, obtained from https: //www. bnl. gov/eic/machine. php. 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 1/10

Brookhaven e. A Solenoid Tracker (Be. AST) ions electrons Alexander Kiselev. “Be. AST Detector. ” Argonne EIC User Group Meeting. 2016. 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 2/10

Gas Electron Multiplier (GEM) – What is it? • Detects charged particles • Several ionization stages amplify original signal • Amplified signal is read out using an array of conducting strips • Position tracker • Output signal pinpoints location of particle as it goes through detector 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 3/10

GEM Design Comparison • CMS • PCB support structure • 3 foil stack • Long history with developing GEMs • EIC • Requires reduction in mass • 5 foil stack • Prototyping phase 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 4/10

Inner Frames • Separate the foils at a certain spacing • Connect the GEM stack to support frames via pull-out parts • Materials: • ABS (white) • PEEK (tan) 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 5/10

Pull-out Parts • Attach the GEM stack to the support frames • Holds stretching screws in place as GEM stack is stretched • Materials: • ABS (white) • PEEK (tan) 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 6/10

GEM Construction • Attach pull-out parts to read-out support frame • Build GEM stack • Attach stack to pull-out parts • Stretch stack • Place outer frame around pullouts • Close chamber with second support frame 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 7/10

Capacitance of Foils and Gaps 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 8/10

Impedance of Foils and Gaps 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 9/10

Conclusions and Future Work • Reducing mass in active area leads to issues associated with stretching the GEM stack • Spacing becomes less uniform • Foils become more likely to touch, leading to poor performance • Introduction of PEEK pull-outs indicates replacement of ABS with PEEK is a solution to this problem • 1 mm ABS inner frame layers have been replaced with 2 mm PEEK parts • Should improve capacitance of and between foils 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 10/10

Thank you! Questions? 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 11

References [1] “Electron Ion Collider: The Next QCD Frontier. ” BNL and JLab. ar. Xiv: 1212. 1701. 2007. [2] F. Sauli. “GEM: A new concept for electron amplification in gas detectors. ” Nuclear Instruments and Methods in Physics Research A 386. 1997. 08 September 2021 Construction and Test of a Modular GEM for EIC, FAS 2019 12