Far-Forward Calorimetry with the SiD and FCAL collaborations ALCW15 - - PowerPoint PPT Presentation

▶
far forward calorimetry with the sid and fcal
SMART_READER_LITE
LIVE PREVIEW

Far-Forward Calorimetry with the SiD and FCAL collaborations ALCW15 - - PowerPoint PPT Presentation

Dec 21, 2022 193 likes •620 views

Far-Forward Calorimetry with the SiD and FCAL collaborations ALCW15 Meeting, KEK April 20-24 2015 Bruce Schumm UC Santa Cruz Institute for Particle Physics FCAL Collaboration SiD efforts on ILC far-forward calorimetry (LumiCal, BeamCal are

slide-1
SLIDE 1

Far-Forward Calorimetry with the SiD and FCAL collaborations

ALCW15 Meeting, KEK April 20-24 2015

Bruce Schumm UC Santa Cruz Institute for Particle Physics

slide-2
SLIDE 2

2

FCAL Collaboration

SiD efforts on ILC far-forward calorimetry (LumiCal, BeamCal are done within the context of the broad FCAL collaboration ~70 physicists; ~20 institutions Current SiD contributions are solely to BeamCal: *) Front-end electronics design (BEAN chip) *) Sensor technology studies (SLAC T506 radiation damage studies) *) Beamcal reconstruction and physics studies

slide-3
SLIDE 3

3

Lumical

  • Measure luminosity precisely

Beamcal

  • Hermeticity (2 physics)
  • Real-time monitoring of beam

targeting

Generic ILC Detector

slide-4
SLIDE 4

4

BeamCal Front-End Electronics (BEAN Chip)

Lead: Prof. Angel Abusleme Pontifica Universidad Catolica de Chile

slide-5
SLIDE 5

5

Basic BeamCal Readout Design Considerations

  • 100% occupancy: beam-beam backgrounds

will illuminate most channels on every beam crossing

  • Large dynamic range (up to 40pC)
  • MIP calibration
  • Real-time beam condition monitoring (real-

time addition of 32 readout channels)

slide-6
SLIDE 6

6

slide-7
SLIDE 7

7

BEAN Chip Ongoing Work

  • Refined filtering techniques to maximize S/N
  • Explore non-linear ADC
  • Testing and characterization
  • Digital back-end (must store entire train)
  • Contribution to systems development

(testbeam prototype)

slide-8
SLIDE 8

8

SLAC T506 Electromagentic Radiation Damage Study Update and Plans

slide-9
SLIDE 9

LCLS and ESA

Use pulsed magnets in the beam switchyard to send beam in ESA.

Mauro Pivi SLAC, ESTB 2011 Workshop, Page 9

slide-10
SLIDE 10

2 X0 pre-radiator; introduces a little divergence in shower Not shown: 4 X0 and 8 X0 radiators just before and after sensor Sensor sample

Surround sensor with Tungsten as in calorimeter  Realistic electromagnetic shower

slide-11
SLIDE 11

11

Dose Rates (Including 1 cm2 Rastering)

Mean fluence per incident e-

Maximum dose rate (10.6 GeV; 10 Hz; 150 pC per pulse): 28 Mrad per hour

Confirmed with RADFET to within 10%

slide-12
SLIDE 12

12

T506 Si Doses

“P” = p-type “N” = n-type “F” = float zone “C” = Czochralski

slide-13
SLIDE 13

13

Results: NC sensors

Dose of 220 Mrad Incidental annealing ~15% charge loss at 300 ns shaping

slide-14
SLIDE 14

14

T506 GaAs Doses

New this past year: (5x5)mm2 GaAs pad sensors via Georgy Shelkov, JINR Dubna Irradiated with 5.7 and 21.0 Mrad doses of electromagnetically-induced showers Irradiation temperature 3oC; samples held and measured at -15oC

slide-15
SLIDE 15

15

GaAs Charge Collection: 5.7 Mrad Exposure

  • 15-20% charge loss at 300 ns shaping
  • Seems to worsen with annealing
  • Sensor detached at 30o annealing step

1 2 3 4 5 6 7 8 200 400 600 800 1000 1200

Median Charge (fC) Bias Voltage (V)

Compiled Median Charge Curves for GaAs18

Pre_irr Pre_ann 22.8C

GaAs Dose of 5.7 Mrad

slide-16
SLIDE 16

16

GaAs Dark Current (-100 C)

0.02 0.04 0.06 0.08 0.1 0.12 0.14 200 400 600 800 1000 1200

Current (µA) Bias Voltage (V)

Current vs Bias Volatge

Pre-Anneal 22.8C

  • O(100 nA/cm2) after 6 MRad irradiation
  • Not observed to improve with annealing
slide-17
SLIDE 17

17

Radiation Damage Plans/Opportunities

  • Silicon sensor studies to high dose, careful

monitoring/control of currents, annealing

  • Further sensor types (GaAs, Sapphire, SiC)
  • Instrumentation support (FPGA, analysis

software)

  • Silicon sensor for prototype FCAL (ongoing

CERN/DESY testbeam studies)

slide-18
SLIDE 18

18

BeamCal Simulation Efforts

slide-19
SLIDE 19

19

Pairs from Beam-Beam Interaction: ~10 TeV per Crossing

slide-20
SLIDE 20

20

BeamCal Reconstruction: Basic Idea

  • Find top 50 energy depositions in layer

near shower max

  • Extend each longitudinally and sum

energy in layers

  • If one is some number of sigma (cut)

above mean background, accept as signal

  • cut is single number (r,φ-independent)

chosen to select 10% of events for which there is nothing but pair background

slide-21
SLIDE 21

21

Sample Study: Value of AntiDiD

Tom Markiewicz, SLAC N.B.: “No DID” really means “No Anti DID”

slide-22
SLIDE 22

22

Preliminary Results: With and Without AntiDID; also, comparison with DBD (SiD02)

Signal: 50 GeV Electrons

slide-23
SLIDE 23

23

BeamCal Simulation Cornucopia

Many studies underway/planned/need planning Instrumentation

  • AntiDID of any use?
  • “Plug region” between two holes needed? If not, what is
  • ptimal geometry?
  • Efficiency vs. L* (common SiD/ILD L*?)
  • Further optimization of reconstruction

Physics:

  • Rejection of two-photon backgrounds to

– Nearly-degenerate SUSY – Hνν

  • Rejection of (radiative) Bhabha

Etc…

slide-24
SLIDE 24

24

SiD BeamCal “Opportunties”

Many areas of ongoing work that offer opportunities for increased effort and collaboration

  • BEAN chip development (contact Angel

Abusleme)

  • T506
  • Simulations
  • Or: whatever you see as relevant and of interest

 Talk to us  Attend next FCAL collaboration meeting

 DESY Zeuthen 20-21 October

If this machine moves forward, we are going to need to really focus seriously on design.

slide-25
SLIDE 25

25

Backup

slide-26
SLIDE 26

nn

26

MDI Q1 cont’d: Anti-DiD needed?

No DID AntiDID # Hits Energy #Hits Energy Out 3cm exit 17.9% 78.4% 81.9% 85.4% Out 2cm entrance 1.8% 0.4% 0.6% 0.3% Hit the plug 74.9% 15.2% 6.7% 2.8% Outside the plug 5.4% 6.0% 10.9% 11.4%

“Plug”

Conclusion:

  • The Anti-DID really only helps in the plug

region between the beam pipes

  • Without the plug to create secondaries,

VXD backgrounds should be LESS with no Anti-DID and radiation dose to BEAMCAL should be less  What about the physics?

Tom Markiewicz, SLAC

slide-27
SLIDE 27

27

R=5mm =0 R=5mm =/2

Energy deposition (summed longitudinally) for various low-radius points on BeamCal

R=5mm =3/2 R=5mm =

slide-28
SLIDE 28

28

MDI Q2: BeamCal Location and Geometry

  • First step: Need to (re)-learn how to simulate the

SLD IP and BeamCal environment  underway

  • Need to center BeamCal on exit hole (correct?)
  • Factorize BeamCal efficiency estimates: total

efficiency a product of – Geometrical efficiency (did the electron hit the instrumented region?) – Instrumental efficiency (if so, was an electron reconstructed?)

slide-29
SLIDE 29

29

Factorized efficiency vs radius results for 100 GeV electrons

Geometrical efficiency Instrumental efficiency Total efficiency

Radius in mm Radius in mm Radius in mm

  • What happens if “plug” is

removed (VXD and BeamCal backgrounds)?

  • What is effect on SUSY

sensitivity in degenerate scenarios?

slide-30
SLIDE 30

30

Hadronic Processes in EM Showers

There seem to be three main processes for generating hadrons in EM showers (all induced by photons):

  • Nuclear (“giant dipole”) resonances

Resonance at 10-20 MeV (~Ecritical)

  • Photoproduction

Threshold seems to be about 200 MeV

  • Nuclear Compton scattering

Threshold at about 10 MeV;  resonance at 340 MeV  These are largely isotropic; must have most of hadronic component develop near sample

slide-31
SLIDE 31

31

1 inch

Sensor

Pitch adapter, bonds

Daughter Board Assembly

slide-32
SLIDE 32

32

Daughter/Readout Board Assembly

slide-33
SLIDE 33

33

Sensor + FE ASIC DAQ FPGA with Ethernet

Charge Collection Apparatus

  • Readout: 300 ns
slide-34
SLIDE 34

34

Channel-over- threshold profile Efficiency vs. threshold

Median Collected Charge

Charge Collection Measurement

2.3 MeV e- through sensor into scintillator

slide-35
SLIDE 35

35

Results: NF Sensor to 90 Mrad, Plus Annealing Study

Limited beneficial annealing to 90oC (reverse annealing above 100oC?)

Dose of 90 Mrad

slide-36
SLIDE 36

36

Compare to Direct Electron Radiation Results (no EM Shower)

Roughly consistent with direct result

kGy

Georgy Shelkov, JINR 1000 kGy = 100 Mrad

slide-37
SLIDE 37

Single-Channel Readout

100 200 300 400 500 600 700 0.5 1.5 2.5 3.5 4.5 5.5 6.5 7.5 8.5 9.5 Output Voltage (mV) Input Charge (fc)

Output Voltage (mV) vs Input charge (fc)

30 pf 25 pf 20 pf 15 pf 10 pf 5 pf 0 pf 20 pf (10uA) 20 pf (88uA) Linear (30 pf) Linear (25 pf) Linear (20 pf) Linear (15 pf) Linear (10 pf) Linear (5 pf) Linear (0 pf) Linear (20 pf (10uA)) 0.2 0.4 0.6 10 20 30 40 Noise (fC) Capacitance (pF)

Noise (fC) vs Load Cap(pF)

Needed for high-dose GaAs, and SiC (0.25 fC signal) and Sapphire (0.09 fC signal) Lower-noise amp/shaper under development

slide-38
SLIDE 38

38

Plans for T506

Have been promised beam time this spring/summer Hoping for high intensity running; SLAC has not yet announced plans and offered running slots Continue Si irradiation studies to high fluence

  • Careful annealing studies
  • Studies leakage currents as well as charge

collection Single-channel readout for novel sensors

  • Assess 20 Mrad GaAs sample
  • Sapphire irradiation (levels?)
  • Silicon Carbide (levels?)
slide-39
SLIDE 39

39

Results: PF sensors

Doses of 5 and 20 Mrad No annealing

slide-40
SLIDE 40

40

Results: PC sensors

Dose of 20 Mrad No annealing

slide-41
SLIDE 41

41

Results: NF sensor for low dose

Doses of 5 and 20 Mrad No annealing