An overview of the DUNE 35 ton prototype at Fermilab Thomas Karl - - PowerPoint PPT Presentation

An overview of the DUNE 35 ton prototype at Fermilab

Thomas Karl Warburton New Perspectives June 13 2016

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

DUNE - Deep Underground Neutrino Experiment

• The flagship experiment of America’s Neutrino program, due to start

taking data in 2024, and beam data in 2026 with 10 kton active LAr.

• Full completion of four modules by early 2030’s.
• Staged construction of 4 x 10 kton fiducial LAr detectors.
• The detector will be a single phase LArTPC.
• Will have a high precision near detector, technology still to be decided.
• Designed to have a very rich neutrino oscillation programme, plus

searches for nucleon decay and neutrinos from supernova bursts.

2 Wide band neutrino beam with peak energy 2.5 GeV, and an initial flux of 1.2 MW which can be upgraded to over 2 MW. Far Detector at depth of 4800 ft, to suppress cosmogenic background

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

The path to realising DUNE

• Neutrino platforms at both CERN and Fermilab provide important

development and prototyping paths.

3

WA105: 1x1x3 m3

2016 2018

WA105

Dual-Phase

SBND 35-t prototype ICARUS MicroBooNE

2015

DUNE SP PT @ CERN

LBL SBL Single-Phase 2018

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

The 35 ton prototype

4

• Designed as one of a series of

prototypes for LBNE.

• Absorbed into the

prototyping effort for DUNE.

• Phase I, Jan 2014.
• Demonstrate that a

membrane cryostat can hold LAr at high purity.

• Phase II, Nov 2015 - Mar 2016
• Test detector design and

readout technologies for DUNE.

Schematic of the 35 ton cryostat

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

Purity during Phase I run

5

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

The 35 ton Phase II

6

• An important step in developing

the FD.

• Detector design features:
• Wrapped wire planes
• Multiple drift volumes
• Cold electronics
• Triggerless DAQ operation
• FR4 printed circuit board field

cage

• Light-guide style photon

detectors

• All items are part of the FD

design and before December 2015 all but one had not been demonstrated to work in an integrated system.

Schematic of the 35 ton phase II

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

The cosmic ray counters

7

• Layers of plastic scintillator

panels.

• Used for triggered running.
• Activated when have a

‘coincidence’ on two

• ppositely facing counters.
• Orientated to give maximal

coverage of the detector.

• Particles crossing APAs
• Particles traversing

detector

• Particles travelling vertically
• Allow interaction times to be

assigned to cosmic events during continuous running

Labelled diagram of the 35 ton counters used for triggering data

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

Purity during Phase II run

8

Pump start PrM2&3, both long PrMs midway heights in cryostat (these lifetimes may drop a bit ~10% if using PrM0 as a constraint) Site wide power outage LN2 Cooling Loss Tubing break Date 2/11/16 2/29 3/19 1.5 3 4.5 6 Electron Lifetime (ms) 3/9 2/20

• Same purity level achieved as in Phase I, which was quickly recoverable.
• Purity level in 35 ton is cryostat limited, not detector component limited.

Preliminary

Liquid Argon purity and electron lifetime during the phase II run

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

Event display for a through-going muon

9

• Orientation of wire planes and track angles triggered on leads to:
• Good collection plane coverage - strong signals on many wires.
• One plane seeing charge deposited on many wires - weak signals on many wires.
• One plane seeing charge deposited on few wires - strong signals on few wires.

Collection Plane Induction Plane Induction Plane

Wire Tick Dead wires Deposited charge on a colour scale

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

Event display for an electromagnetic shower

10

• Event display after noise

mitigation is shown.

• ‘Stuck’ ADCs are

removed.

• Coherent noise is

removed.

• A frequency filter is

applied.

• Stronger signals due to

more deposited charge.

Wire number Time tick (500 ns)

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

Hit disambiguation using cosmic ray counters

11

• Due to wrapping disambiguation is required.
• Existing algorithm assumes ‘triple points’
• Absence of induction signal can cause a hit to be

discarded as noise.

• Counters offer a method of performing disambiguation.
• Hits have to be within a 3 dimensional coincidence

window.

• Removes noise hits.
• However, tracks which did not produce a counter

coincidence are discarded.

• Can use unambiguous collection plane signals to

constrain ambiguous induction signals.

Z Position (cm) X Position (cm) Collection plane hits in the XZ plane

Preliminary

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

Reconstructed tracks

12

• Digitised waveforms

shown on the left

• Same structure as

previous event displays.

• Fourth window shows

reconstructed hits in

• range.
• Three dimensional view

shown on the right.

• XZ plane shown in top

window

• YZ plane shown in

bottom window

• X position of tracks is

not corrected.

Preliminary Preliminary

Z (cm) Z (cm) Y (cm) X (cm) Z (cm) Z (cm) Y (cm) X (cm) Wire Wire Tick Tick Col Ind Ind Col Ind Ind

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

Ongoing Analyses

13

• Measuring purity with TPC data, crude

analysis shown below.

• Measuring longitudinal and transverse

diffusion.

• Using through going muons to study

APA gap width.

• Using through going muons to study

charge collected in the centres of APAs.

Alex Booth, Lancaster Jonathan Insler, LSU Difference in counter and SIPM time Time (us) Counts

• Using Michel electrons to study

energy resolution.

• Event time resolution of the photon

detectors.

• Interaction time assignment from

photon detectors, initial result shown below

• Signal/Noise ratio of the TPC.

Crude measurement of purity Time in ticks (500 ns) Charge (ADC)

Preliminary Preliminary

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

Conclusions

• Phase II of the 35 ton showed that cryostat purity was not

instrumentation limited.

• Cosmic ray counters will play an important role in data analysis
• f the 35 ton.
• Developing tools to recover from low signal / noise in the data.
• Lots of analyses are progressing nicely.
• The 35 ton is a vital stepping stone in building the DUNE far

detectors.

• As Bruce said, exciting times lie ahead!

14

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

Backup slides

15

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

Schematic of the detector with two counter coincidences

16

X = -7cm z = 154cm z = 309cm ~30cm z = 0cm 111 111 111 111 111 111

3 5 2 4 6 7 1

SU3 SL4

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

Stuck ADC code removal

17

Time (ticks) 1700 1720 1740 1760 1780 1800 1820 1840 ADC Counts 1780 1800 1820 1840 1860 1880

Pre-sticky ADC codes Sticky ADC codes applied Sticky ADC code mitigation

ADC Vectors with and without Stuck 6 LSBs

• Stuck codes were observed in ADC

chips, this can be recovered by removing latched values and extrapolating between neighbouring samples.

• A redesign of the chip is being tested

for future use.

• Code developed by Jonathan Insler,

presented here.

Raw signal Unstick signal plus fast hit

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

The Wiener frequency filter

18

• Spike in noise frequency around 0

frequency.

• Collection plane signal goes to very

low frequency, so want to keep all but the very lowest frequencies.

• Induction planes have more of a

peaked structure, with little components at the lowest frequencies. FFT of signal U plane FFT of noise U plane (S2-N2)/(S2+N2) Z plane

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

LAr TPC concept

19

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

LAr TPC concept

20

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

LAr TPC concept

21

Karl Warburton, An Overview of the DUNE 35 Ton Prototype at Fermilab

LAr TPC concept

22

• A step-by-step guide as to how

hits are combined into tracks.

• The first image shows raw

signals

• The second image shows the

signals being reconstructed into hits

• The third image shows clusters

being combined into tracks.

• The 35 ton has and DUNE will

have, a step between images 2 and 3 where due to the wrapped wires, hits have to be disambiguated as to which part of a wire the hit was on.