K2k scibar
This presentation is the property of its rightful owner.
Sponsored Links
1 / 29

K2K 実験 SciBar 前置ニュートリノ検出器 PowerPoint PPT Presentation


  • 66 Views
  • Uploaded on
  • Presentation posted in: General

K2K 実験 SciBar 前置ニュートリノ検出器. 読み出しシステムと時間情報の較正. 久野研  田窪 洋介. Contents. K2K experiment SciBar detector & readout system Cosmic ray trigger system Timing calibration Conclusion. K2K Experiment. SciBar detector. SciFi detector. Super-Kamiokande. 1kt water cherenkov detector. Pure ν μ. ν μ.

Download Presentation

K2K 実験 SciBar 前置ニュートリノ検出器

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


K2k scibar

K2K実験 SciBar前置ニュートリノ検出器

読み出しシステムと時間情報の較正

久野研  田窪 洋介


Contents

Contents

  • K2K experiment

  • SciBar detector & readout system

  • Cosmic ray trigger system

  • Timing calibration

  • Conclusion


K2k experiment

K2KExperiment

SciBar detector

SciFi detector

Super-Kamiokande

1kt water cherenkov detector

Pureνμ

νμ

L = 250km

Near Detectors

MRD(Muon Range Detector)

K2K experiment uses neutrinos made by the accelerator

KEK 12GeV PS

Pure νμ beam whose Flux and energy are well known, can be obtained .


Neutrino oscillation

Neutrino Oscillation

Square mass difference(eV2)

Flight length (km)

Oscillation

Probability

=

Neutrino energy (GeV)

Mixing angle

Data

K2K current status

0.6 GeV

Best Fit

Best fit

Δm2 = 2.8×10-3(eV2)

sin22Θ= 1.0

No oscillation

En


Neutrino interaction

m

pm

nm

qm

n

proton

Neutrino interaction

CC-QE Interaction

  • Assuming Charged Current Quasi-Elastic interaction

    • Dominant process around 1GeV neutrinos.

  • Oscillation maximum ~0.6GeV

  • Non-QE interactions are backgrounds for En measurement

CC-nonQE Interaction

m

nm

N

pion

nucleon


Scibar detector

n

SciBar detector

  • Extruded scintillator with WLS fiber readout

  • Neutrino target is scintillator itself

  • 2.5 x 1.3 x 300 cm3 cell

  • ~15000 channels

  • Light yield

  • 7~20p.e./MIP/cm (2 MeV)

  • Detect 10 cm track

  • Distinguish proton from pion by using dE/dx

  • High 2-track CC-QE efficiency

  • Low non-QE backgrounds

Extruded

scintillator

(15t)

EM calorimeter

3m

Multi-anode

PMT (64 ch.)

3m

1.7m

Wave-length

shifting fiber

Just constructed in this summer!


Detector components

Detector Components

DAQ board

64ch MAPMT

Front-end board


Scintillator wls fiber

Scintillator & WLS Fiber

Scintillator

1.8 mmφ

  • Size : 1.3×2.5×300 cm3

  • Peak of emission spectrum : 420 nm

  • TiO2 reflector (white) : 0.25 mm thick

300 cm

  • Kuraray

    • Y11(200)MS 1.5mmφ

    • Multi-clad

  • Attenuation length ~3.6m

  • Absorption peak ~430nm

  • Emission peak ~476nm

1.3 cm

2.5cm

Wave-length Shifting Fiber

Charged particle


Multi anode pmt

Multi-anode PMT

Top view

  • Hamamatsu H7546 type 64-channel PMT

    • 2 x 2 mm2 pixel

    • Bialkali photo-cathode

    • Compact

    • Low power : < 1000V, < 0.5mA

    • Typical gain : 6 x 105

    • Cross talk : ~3%

    • Gain uniformity : ~20%(RMS)

    • Linearity : ~200 p.e.@ 6 x 105


Readout electronics

sample&hold

preamp.

VA serial output

slow shaper

CH1

TA (32ch OR)

fast shaper

discri.

multiplexer

CH2

CH32

Readout Electronics

1.2ms

hold

∝ charge

VATA Chip

PMT

signal

Front-end board

VA/TA chip


Daq board

DAQ board

  • Control of VA readout sequence

  • Setting of VA trigger threshold

  • A/D conversion of VA serial output by FADC

  • 8 front-end board (8 MAPMT) are connected to one DAQ board.

8 front-end boards(8×64ch)

16ch×2 TA signal


Scintillator installation

Scintillator Installation

64 X and 64 Y layers

X and Y planes were glued


Wls fiber and pmt installation

WLS Fiber and PMT installation


Logic diagram for cosmic ray trigger

Logic Diagram for Cosmic Ray Trigger

Identification of hit track

Make coincident with two trigger signals

Top

112 TA

Trigger Board

7 DAQ Board

56 Front-end Board

56 MAPMT

Master trigger board

Timing Distributor

Side

TRG

112 TA

Trigger Board

7 DAQ Board

56 Front-end Board

56 MAPMT

Distribute signals made from the trigger signal to other modules

Top view

Side view

We use half of the TA channels (224ch/448ch) for cosmic ray trigger.


Trigger board

Trigger Board

Output : 1ch

input : 128 ch (16×8)

Output : 16 ch

FPGA decide to make trigger signal.

  • VME 9U module

  • Front panel : input 128 (16×8) ch LVDS/ECL

  • Back plane : output 16ch LVDS/ECL

  • Using FPGA, trigger logic can be easily implemented for any combinations of 128 inputs.


Timing distributor

Timing Distributor

Daughter board

16ch NIM I/O

8ch LVDS I/O

16×2ch LVDS/ECL Input

FPGA

  • VME 6U module to distribute timing signals made by trigger system to DAQ backend boards

  • 4ch NIM I/O on main board + 2 daughter boards

Daughter board

16×2 ch LVDS/ECL Input

16ch NIM I/O

  • Flexible data processing is realized using FPGA.


Requirement for cosmic ray trigger

Requirement for Cosmic Ray Trigger

  • Horizontally through-going muons are taken for calibration effectively.

  • Distribution of cosmic ray hits is uniform.

  • Decision time is less than 100 ns (due to the cable length of electron catcher)

  • 32ch OR’ed signals from TA*1 (fast-triggering ASIC) are trigger board input signals.


Trigger design

Trigger Design

  • Trigger is generated, based on the hit pattern identification.

Preparing hit patterns, track pattern matching them is selected.

  • Track which is less than 45 degree of zenith angle is taken.

Zenith angle > 45 degree

Zenith angle < 45 degree

  • Pre-scale factor can be set on the hit pattern to make hit distribution uniformly.


Achieved performance current status

Achieved Performance & Current Status

Achieved performance

  • Decision time is 100 nsec.

  • Single rate of one TA is about 100 Hz.

  • Trigger rate is about 100 Hz.

  • Data acquisition rate is about 20 Hz.

Current Status

We now use a trigger logic for the commissioning. We make “or” signals of every other layer, and make coincident with those of the top and side separately. We make “and” signal of the top and side.


Angle distribution of cosmic ray event

Angle distribution of cosmic ray event

taken by commissioning trigger

Zenith angle(degree)

60

0

Horizontal line

-60

-80

0

80

Azimuth angle (degree)


Hit distribution of cosmic ray event

Hit distribution of cosmic ray event

taken by commissioning trigger

250

250

Vertical position(cm)

Horizontal position(cm)

150

150

0

0

80

160

80

160

Z(cm)

Z(cm)

ν

ν


Event display of cosmic ray event

Event display of cosmic ray event

Side View

Top View

μ

μ


Tq distribution

TQ Distribution

Correction function : ΔT = A/(ADC +B) + C A,B,C : const

ΔT = T(X12Z1) – T(X12Z2)

ΔT(nsec)

ΔT(nsec)

25

25

ΔT = 1719.8/(ADC +65.5)-5.6

10

10

-5

-5

600

0

300

0

300

600

ADC

ADC


Time resolution

Time Resolution

ΔT = T(X12Z1) – T(X12Z2)

Before TQ correction

After TQ correction

count

count

Time resolution

σ/√2 = 2.83 nsec

Time resolution

σ/√2 = 1.70 nsec

ΔT(nsec)

ΔT(nsec)


Light velocity in the fiber

Light velocity in the fiber

y15z8

ΔT(nsec)

ΔT(nsec)

0.05847E-01 ±0.8594E-03

Light velocity in a fiber = 17.2 nsec/cm

Δx(cm)

Δx(cm)


Conclusion next step

Conclusion & Next step

  • Cosmic ray data is taken by commissioning trigger and useful for timing and energy calibration, and so on.

  • Timing correction was done by cosmic ray data.

  • Timing resolution is 1.70 nsec.

  • Light velocity in a fiber is 17.2 nsec.

Next step

Ability of direction ID by using TOF will be estimated.


Cc qe candidate

n

n

CC-QE candidate

Top view

Side view

  • Area of circle is proportional to ADC

  • Hits along the proton track are larger

p

μ

μ

p


3 track event

n

n

3-Track Event

Top view

Side view

1

3

3

2

2

1


Neutral current p 0 candidate

n

n

Neutral Current p0 Candidate

Top view

Side view

e

Vertex!

e

γ

γ

π0

π0

γ

e

e


  • Login