DECAL: DMAPS S ENSORS FOR D IGITAL E LECTROMAGNETIC C ALORIMETRY S - - PowerPoint PPT Presentation

▶
decal dmaps s ensors for d igital e lectromagnetic c
SMART_READER_LITE
LIVE PREVIEW

DECAL: DMAPS S ENSORS FOR D IGITAL E LECTROMAGNETIC C ALORIMETRY S - - PowerPoint PPT Presentation

Mar 12, 2023 274 likes •470 views

DECAL: DMAPS S ENSORS FOR D IGITAL E LECTROMAGNETIC C ALORIMETRY S TEVE W ORM A , P. A LLPORT A , R. B OSLEY A , L. C HEN B , J. D OPKE B , S. F LYNN A , L. G ONELLA A , I. K OPSALIS A , K. N IKOLOPOULOS A , P. P HILLIPS B , T. P RICE A , I. S

slide-1
SLIDE 1

DECAL: DMAPS SENSORS FOR DIGITAL ELECTROMAGNETIC CALORIMETRY

STEVE WORM

A, P. ALLPORT A, R. BOSLEY A, L. CHEN B, J. DOPKE B, S. FLYNN A, L.

GONELLA

A, I. KOPSALIS A, K. NIKOLOPOULOS A, P. PHILLIPS B, T. PRICE A, I. SEDGWICK B,

  • G. VILLANI

B, N. WATSON A, M. WARREN C, F. WILSON B, A. WINTER A, Z. ZHANG B

AUNIVERSITY OF BIRMINGHAM BSTFC RUTHERFORD APPLETON CUNIVERSITY COLLEGE LONDON

MAY 29, 2018

slide-2
SLIDE 2

OUTLINE AND OVERVIEW

  • IntroducIon: Calorimetry with silicon readout

– Analogue (e.g. CALICE, CMS HGCAL) – Digital (e.g. SPiDER, ALICE FoCal)

  • SimulaIon results: Single parIcle resoluIons
  • Sensor R&D: Reconfigurable radiaIon-hard DMAPS
  • Conclusions

2

Analogue: Sum energy deposited in a cell Digital: Sum the number of particles in a cell

slide-3
SLIDE 3

DIGITAL CALORIMETRY: TEST BEAMS

  • SPiDeR: pixel counIng gives correct shower shape

– CERN testbeam using EU Telescope (Mimosa-26) – Tracks in first 3 layers, shower in W, measure core in 4th layer 15 cm from W

  • Digital Calo Example: ALICE FoCal

– High granularity to separate showers – DESY & SPS test beams: 24 plane prototype; four Mimosa-23 (30 μm Pitch) with W

3

[Rocco et al, ICHEP 2016]

slide-4
SLIDE 4

ANALOGUE READOUT

  • Detector ConfiguraIon

– Concentric octagonal geometry – 50 layers of 0.6 X0 W – 5x5 mm2 pixels – 300 μm thick sensiIve region

  • PandoraPFA* gives jet energy

resoluIon of <4% for jets up to 250 GeV Excellent linearity, resolu=on possible

4

[*hlps://arxiv.org/abs/0907.3577]

Linearity Resolution

5x5 mm2 Pads

slide-5
SLIDE 5

DIGITAL READOUT

  • Detector ConfiguraIons

– Concentric cylinder geometry – 50x50 μm2 pixels – 18 μm thick epitaxial region

▼ 50 layers of 0.6 X0 W

○ 30 layers of 1.0 X0 W

☐ 50 layers of 0.6 X0 Pb

30 layers of 1.0 X0 Pb

  • MIP MPV ~1400 e- with

threshold of 480

  • For 50 layers of Tungsten,

energy linear up to ~300 GeV

5

slide-6
SLIDE 6

DIGITAL READOUT

  • Octagonal barrel geometry

– 50 layers of 0.6 X0 W – 50x50 μm2 digital pixels – 5x5 mm2 counIng pads – 18 μm thick epitaxial region – 3 mm air for PCB, services, etc

Good performance for realis=c geometry

6

Linearity Resolution

50x50 µm2 Pixels

slide-7
SLIDE 7

NON-LINEARITY AND MVA

  • Can you recover linearity in soqware?

– MVA package: LinearDiscriminant, MulI-Layer Perceptron (ANN) – Simulated DECAL: energy range 10 - 1000 GeV, 50 layers 2.1 mm W – Input: number of pixel hits per layer, grouped in 5 layers (1-5, 6-10, etc)

Linearity recovered over full range (to 1 TeV)

7

slide-8
SLIDE 8

DECAL PILEUP STUDIES

  • Simulated pile-up using Pythia min bias events

– ⟨µ⟩=1000 yields 3.5M pixels above threshold in DECAL barrel – Energy in first layer vs eta follows same trend as FCC-hh LAr baseline studies – Pixels above threshold vs eta also have similar trend

  • 500 GeV e-; 50k hit pixels swamped by pileup

– First alempts at reducing hits very promising

– ALL PIXELS, MAX_STAVE, 10k ROI, TRUTH ⟨µ⟩=0 – Simple cuts reduce BG by orders of magnitude

  • Next: careful study with clustering, energy resoluIon

8 105 104 103 102 10

1

0 10 20 30 40 50 Layer pixels / layer

decal_ParticlesPerEta_layer1

Entries 290 Mean 1.015 Mean y 2632 Std Dev 0.5857 Std Dev y 2029 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Eta 1000 2000 3000 4000 5000 6000 7000 8000 Pixels / 0.1 eta / event

decal_ParticlesPerEta_layer1

Entries 290 Mean 1.015 Mean y 2632 Std Dev 0.5857 Std Dev y 2029

decal_ParticlesPerEta_layer1

Entries 290 Mean 1.015 Mean y 0.04408 Std Dev 0.5857 Std Dev y 0.03913 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 Eta 0.02 0.04 0.06 0.08 0.1 0.12 0.14 0.16 Edep / 0.1 eta / event

decal_ParticlesPerEta_layer1

Entries 290 Mean 1.015 Mean y 0.04408 Std Dev 0.5857 Std Dev y 0.03913

0 0.4 0.8 1.2 1.6 2.0 Eta 0.16 0.12 0.08 0.04 8000 6000 4000 2000 E / 0.1eta / event pixels / 0.1eta / event 0 0.4 0.8 1.2 1.6 2.0 Eta

slide-9
SLIDE 9

DECAL TEST SENSOR

  • DECAL monolithic acIve pixel test sensor features

– Reconfigurable: strip mode for parIcle tracking, or pad mode (counts above threshold) for digital calorimetry – TowerJazz 180 nm, 18 μm epi, standard (opIcal) process – 5 mm2 pixel matrix of 64×64 pixels with pitch of 55×55 μm2

  • Sensor matrix now under test

– Four collecIon electrodes/pixel – Trim, preamp, shaper, discriminator – 25 ns digital output – Analog and digital tests ongoing Sensor shows analogue response (works!)

9

slide-10
SLIDE 10

DECAL ARRAY: STRIP MODE

  • Strip Mode (1 x 64 pixel array)

– Counts above threshold: 0, 1, 2 or >3 per column – Data rate: 320 Mbit/s x 16 = 4.8 Gbit/s

10

PLL Calibration Shift Register Test Data Shift Register Collated Column Outputs LVDS Output Bias Mapping Strip Logic Pad Logic

64 strip array

(64 x 64 pixels)

slide-11
SLIDE 11

DECAL ARRAY: PAD MODE

  • Pad Mode (16 x 64 pixel array)

– Up to 15 hits in each of 16 columns (240 total) – Lower rate; about 1/4 the LVDS lines

11

PLL Calibration Shift Register

64 x 64 pixel array

Test Data Shift Register Collated Column Outputs LVDS Output Bias Mapping Strip Logic Pad Logic

4 pad array

(each 16 columns wide)

slide-12
SLIDE 12

DECAL PIXEL

  • TowerJazz 180 nm standard (opIcal) process; 18 μm epi

– Four collecIon nodes, low capacitance, expect good signal/noise – OperaIonal with 1-2 volts bias; higher voltage for faster collecIon

  • TowerJazz “modified process” also under invesIgaIon

– Test structures submiled in modified TowerJazz process [NIM A V871, 90-96, 2017] – Full depleIon, low capacitance and good signal/noise demonstrated – Rad hard to few 1015 neutron equiv. [JINST 12 P06008, 2017]

12

Single pixel field: DC Vbias 2 to 10V, without back contact 2V 4V 10V 8V 6V

Poster: H. Pernegger Talk: K. Moustakas

slide-13
SLIDE 13

DECAL DATA ACQUISITION AND SOFTWARE

  • DECAL Data AcquisiIon via NEXYS

Video board (Digilent)

  • Soqware is based on ATLAS ITSDAQ
  • NEXYS board is programmed using Adept

13

slide-14
SLIDE 14

DECAL: STRIP MODE DIGITAL LOGIC

  • OperaIng the chip in strip mode:

– Inject 3 (binary 11), and shiq along the strips – Inject 3 (11), then 2 (10), then 1 (01), shiq along the strips

Digital logic for strip mode works as expected

14

Inject number 3 (11) in the 1st strip Inject numbers 3, 2, 1 in the 1st, 2nd and 3rd strip

slide-15
SLIDE 15

DECAL: PAD MODE DIGITAL LOGIC

  • OperaIng the chip in pad mode:

– Inject the numbers 3, 2, 1 and shiqing along the strips – Compare the injected numbers 3, 2, 1 to the total sum of each output block

Digital logic for pad mode also works as expected

15

Inject numbers 3, 2, 1 in the 1st, 2nd and 3rd strip Inject numbers 3, 2, 1 and total sum

slide-16
SLIDE 16

ANALOGUE PIXEL TEST

  • Laser illuminaIon for analogue pixel in the top leq corner (2nd row 2nd column)
  • Laser-inject charge, observe the outputs of the test pixel
  • Preamplifier, shaper signals & laser trigger measured

16

slide-17
SLIDE 17

ANALOGUE PIXEL TEST

  • Analogue tesIng of single pixels ge~ng started

– Tests vs bias (e.g. 1 or 2 V, below), linearity, etc – Laser scan across matrix – Source tesIng & TCT planned

17

slide-18
SLIDE 18

CONCLUSIONS

DECAL silicon calorimeter designs are progressing:

  • High granularity should allow excellent PFA
  • Pixel counIng gives good energy resoluIon at intermediate energies
  • Problems from pileup and mulIple hits can be miIgated by MVA, clustering
  • Prototype reconfigurable CMOS DMAPS for ECAL, pre-shower, and outer

tracking fabricated at TowerJazz and under evaluaIon

  • Digital logic works (configurable), analogue now under test

18