GEM Tracking Proposal for LEMMA A Colaleo M

GEM Tracking Proposal for LEMMA A. Colaleo, M. Maggi, F. Simone, R. Venditti, P. Verwilligen – INFN Bari

Preparazione test beam: GEMs In vista del test beam 2022 abbiamo bisogno di preparare e integrare tutti I rivelatori gia’ nel 2021. Piano e’ di integrare nel 2021 al CERN nell’area antistante GIF++. • 2 Dedicated Hi-res 10 x 10 triple-GEM • X-Y, 260 mm pitch (75 um resol. ) • Standard CMS GE 2/1 “M 1” and “M 2” modules in muon arms • Trapezoidal, 364 -593 mm resol. • All read out by CMS Phase 2 DAQ M 1 M 2 A. Colaleo et al. 2

Proposed Layout 2 “M 1” e 2 “M 2” (360 -480 um resolution in X – strip ). Camere “ 10 x 10” con risulazione piu spinto (75 um). Per convertire Local Position (Trapezoidal strips) to Global Position (true X, Y) proponiamo di misurare altezza (coord Y) prima & dopo magnete e propagare lo trajectory a M 1 & M 2. . 2

Details GEM ``M 1’’ & ``M 2’’ Standard CMS GE 2/1 M 1 and M 2 modules (trapeziodal shape) with strip pointing to the beam (they are inclined trapezoids). M 1 M 2 M 3 M 4 4

High-Res 10 x 10 Triple-GEM read by CMS DAQ • Provide TRACKER before & after the magnet: 10 x 10 cm 2 • Offered pitch: 260 um = resolution 75 um • New readout board for standard 10 x 10 with 366 strips for each coordinate • Digital readout with VFAT 3: 260 um/ 12 = 75 um 2 1: 10 x 10 Triple GEM with modified readout board: 3*122 = 366 strips in X, Y (260 um pitch) 2: VFAT 3 b hybrid boards 3: SAMTEC cables (new) for high speed ( ~82 EUR/piece) with connectors 4: CMS GEM GE 1/1 GEB 2 2 1 2 2 2 4 Panasonic 130 Triple-GEM (1) 3 GE 1/1 GEB 6 cables x 3 chambers = 18 high speead cables Panasonic 100 VFAT 3 HV 3 b_V 2 (2) GE 1/1 GEB + Opto-Hybrid (not shown) CPT 7 Board in u. TCA crate 5

Costo dei cavi non include IVA: costo cavo 82 Euro, costo connettore= 6 euro

Missioni per test beam Caratterizzazione camere GEM high-res 10 x 10 cm 2 per tracciamento. Integrazione GEM in sistema di readout/trigger in setup al CERN: • 2 settimane tecnici • 1 settimana tecnologo elettronico • 5 settimane fisici 8 k. Euro.

GEMs requests: total Comments # COST GEMs 3 3. 5 k. EUR 10. 5 k. EUR 10 x 10 Samtec cables 18 0. 082 k. Euro 1. 4 k. Euro see page 7 Connectors 36 0. 006 k. Euro 0, 216 k. Euro Mechanics 1 TOTAL 1. 5 k. Euro see page 7 Mecchanics to support the layout 13, 6 8

BACKUP

A. Bertolin September 2018 setup, x vs z 32 31 _ before the magnet (black cross), 31, we had a 10 cm detector in 2018 _ right after the magnet (black cross), 32, the length of a single piece detector should be about 40 cm

A. Bertolin September 2018 setup, y vs z 10 cm height is enough for all detectors except muon ones 31 32 34 33

A. Bertolin Summary of our questions: - Beamspot size (X, Y) at position 32 & 33 * see next slide - Details on amount of e+ / spill, temporal profile of the spill, contamination, such as to be able to estimate the peak rate expected: * The positron beam had a pulsed shape with 4 spills per minute, each spill lasting 4. 8 sec with a typical intensity of 5 e+6 positrons. As anticipated in Sec. ref{sec: analytical}, the spot size was 2 x 2 cm 2 with a typical angular spread of 300 microrad. With the chosen collimators setting the momentum spread was below 1. 5 % cite{mom_spread}. The purity of the beam was in the range 95 - 99 % cite{Charitonidis}. * expected mu+mu- pair per spill: about 1 * expected e+e- pair per spill: about 10 * but we always observed much larger backgrounds, beam related, origin not clearly understood, and not effectively suppressed by the trigger setup we had * in the worse case scenario expect 5 e+6 / 4. 8 sec = 1 MHz … - Expected hit rate in detectors at pos 33 & 34 * same argument as above, would expect a rate of mu+mu- and e+e- in the O(1) Hz range … but always had to cope with much more … 12

A. Bertolin 1) fraction of positrons that do not convert? we have 5 e+6 about 45 Ge. V positrons hitting a 3 cm thick Be target 1 (mu+mu-) + 10 (e+e-) will convert and 5 e+6 - 11 will have some sort of interaction with the relatively thin target and survive 2) will they be bended by the magnet and do they go into the muon arm? or would they go more straight? what happens to the surviving positrons depends on their momentum after the target, let say: _ with momentum in the range [26, 45] Ge. V positrons are not bended enough to be seen downstream of the magnet _ with momentum in the range [18, 26] Ge. V they are recorded as the mu+ _ with momentum < 18 Ge. V they are bended too much and miss the relevant detector What is the mean value of the mu+ and mu- pt ? the momentum is in the range [18, 26] Ge. V, the transverse momentum is VERY small, we want a small emittance hence small transverse momentum see fig. 4 of https: //doi. org/10. 1088/1748 -0221/15/01/P 01036 What is the strength of the magnet? 2. 01 T (September 2018), 2 m long For us it would be important that we "catch" those non converted positrons for our high rate tests. can you elaborate more ? surviving positrons in the range [26, 45] Ge. V would also be nice to measure (momentum mostly) 26 < p < 45 Ge. V p < 18 Ge. V 18 < p < 26 Ge. V

BACKUP Bari, May 11 2020

COMPASS-design Triple-GEM 10 x 10 2 2 2 Standard Design vs our Request 2 2 Special Request Triple-GEM 10 x 10 60 um 320 um 400 um Triple-GEM 10 x 10 cm 2 • Read out by 256 strips (2 x 128) in X (80 um wide) • Read out by 256 strips (2 x 128) in Y (340 um wide) 22 0 u m 25 0 u m 34 0 u m 40 0 u m 80 um 2 100 um 150 um 250 um Triple-GEM 10 x 10 cm 2 • Read out by 366 strips (3 x 122) in X (100 um wide) • Read out by 366 strips (3 x 122) in Y (220 um wide) 8

COMPASS X-Y readout strips 9

COMPASS X-Y performance Clustersize & Nchan > threshold Cluster Q correlation Sources: https: //cds. cern. ch/record/533504/files/open-2002 -004. pdf http: //cds. cern. ch/record/536170/files/ep-2002 -008. pdf Spatial Resolution (For Illustration only) R/O: APV 25 & Charge Weighting !!! 10

2 m m TOTEM R-�� Performance • TOTEM T 2 Triple-GEM Tracker 2 m m 80 um stri pw idth 400 um pitc h PAD Thesis E. Oliveri • Has radially extending Pads from 2 x 2 mm 2 to 7 x 7 mm 2 which are below a layer of strips • Has concentric strips of 80 um width @ 400 um pitch • Design based on COMPASS such that signal induction is 50% on strips (top) and 50% on pads (bottom) • Spatial Resolution: Measured with VFAT 2 !!! ~115 um for the strips (R residuals), exactly what was expected from 400 um/ 12 https: //doi. org/10. 1016/j. nima. 2 009. 07. 006 11