PSROC, February 2, 2005 Sun Yat-San University

Neutrino Telescope Status Neutrino Telescope Status

Ching-Cheng Hsu National Taiwan University

On behalf of NuTel Group

OutlineOutline : :

Overview of NuTel Experiment & Electronics Schematics

Preliminary measurements of Electronics

Conclusion and Prospect

NuTel Experiment Overview NuTel Experiment Overview

PSROC, February 2, 2005 Sun Yat-San University

Using Earth / mountain as target

Signals : Cherenkov light from showers

Only sensitive to :

e : electron shower mostly absorbed in mountain

no extensive air shower generation

appearance

NuTel Optics Design NuTel Optics Design

PSROC, February 2, 2005 Sun Yat-San University

Mirror R : 2.1 m

Mirror Diameter: 1.2 m

Corrector Lens : aspheric formula

Lens Diameter : 0.9 m

0.07 m

2 mDesigned with OSLO optical design software.

The spot size smaller than our pixel size :0.5 degree!

correct spherical aberration

Electronics SchematicsElectronics Schematics

DAQPMT Preamp.

UV filter

TriggerTotal 1024 channels

Start readout10 bit x40 MHzPipelinedADC

16 RAM x 256 x 16 per 8 channelsMirror

Trigger FPGA

FADCbufferRAM

ADC controlFPGA (x4)

cycleRAM

Charge-Sharing Board

PSROC, February 2, 2005 Sun Yat-San University

16 CSB

16x 64 ch.

16 MAPMT

16x64 Pixels

32 DCM,

32x32 ch.

Using two telescopes for stereo observation

Preamp

64 x 16

Feasibility Study of Calibration the NuTel Prototype Detector with Crab NebulaPSROC, February 2, 2005 Sun Yat-San University

15 Slave DCM

Master DCM

Daisy-Chain of Trigger Request

Trigger Decision, System Clock & Reset

Single Board

Computer

DAQ operation rate can be up to 500 Hz with

negligible dead time.

DAQ DAQ

One chassis processes information from 512 channels

Linearity Linearity

Feasibility Study of Calibration the NuTel Prototype Detector with Crab NebulaPSROC, February 2, 2005 Sun Yat-San University

Sum up all the charges

ADC saturated

0.002mV

The total charges we calculate from ADC counts is proportional to the DAC input voltage.

PMT Gain Measurement PMT Gain Measurement

Feasibility Study of Calibration the NuTel Prototype Detector with Crab NebulaPSROC, February 2, 2005 Sun Yat-San University

Al Box Size 185 cm (length) x 23cm x26cm (height)

MAPMT

Preamp High voltage cable

150 cm

The walls inside the box are covered by black blanket.

Connected to DCM

Pedestal Measurement Pedestal Measurement

LED pulse 1KHz, pulse width 75 ns

LED with voltage from 1.92 V to 2.2 V. PMT operational voltage from 650 V to 750 V. Totally 33 combinations.

PMT Pixel ID

PSROC, February 2, 2005 Sun Yat-San University

rms : smaller than 0.5 ADC count

Average all operation conditions

0123456789

10111213141516

0 8 16 24 32 40 48 56 64

Channel number

Pedest

al in

AD

C c

ounts

Pedestals

Sigma(r.m.s)

Pedestals for each pixel are steady

Here are few channels with negative or around 0 pedestals. Maximal r.m.s noise is 0.77 ADC count. Typical noise is between 0.6 and 0.7 ADC counts.

Relative Charge Between PixelsRelative Charge Between Pixels

12

891

57

Hammamatsu H7546

With PMT Voltage 700 V, LED : 2.2 V

0

20

40

60

80

100

120

1 9 17 25 33 41 49 57

PMT Pixel ID

Rel

ativ

e G

ain

Hama800V James800V James700VPMT + Preamp +DCM :

Maybe due to non-uniform light or/and effective area of the channels.

PSROC, February 2, 2005 Sun Yat-San University

Statistics method Statistics method The total components of noise σ:

σ2 = {σno_sig2 } + G*M + {σwith_sig

2} * M2 # of photons coming to PMT, has a Poisson distribution, somean value (M) and RMS (σ0) charge distribution of the PMT

are G = M/N = σ02/ M

Ch.0, HV=650V

y = 0.0005x2 + 2.8447x + 4.7034

R2 = 0.9996

0

100

200

300

400

500

600

700

800

900

0 50 100 150 200 250 300

Y= σ2Ch.0 HV=750V

y = -0.0001x2 + 13.96x + 0.2631

R2 = 0.9999

0

2000

4000

6000

8000

10000

12000

0 100 200 300 400 500 600 700 800

X=M

Ch.0 HV=700V

y = 0.0006x2 + 6.4092x + 15.593

R2 = 0.9996

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 100 200 300 400 500 600 700

X=M

Y= σ2 Y= σ2

X=M

G = 2.84 G = 6.41 G = 13.96

Ch.0, HV=650V

y = 2.9744x + 0.8286

R2 = 0.9994

0

100

200

300

400

500

600

700

800

900

0 50 100 150 200 250 300

Y= σ2Ch.0 HV=700V

y = 6.7454x - 8.2159

R2 = 0.9994

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 100 200 300 400 500 600 700

Ch.0 HV=750V

y = 13.881x + 7.4397

R2 = 0.9999

0

2000

4000

6000

8000

10000

12000

0 100 200 300 400 500 600 700 800

Y= σ2 Y= σ2

X=M X=M X=M

G = 2.97 G = 6.75 G = 13.88

30

40

50

60

70

80

90

100

0 8 16 24 32 40 48 56 64

Hamamatsu Data

Our Measurement

Gain vs Channel numbers ( Gain vs Channel numbers ( G = σ2/M )

The pixels on the two sides have large light collection.

0

2

4

6

01

23

45

67

0,005,0010,0015,0020,0025,0030,0035,0040,0045,0050,0055,0060,0065,0070,0075,0080,0085,0090,00

HV 800 V

PSROC, February 2, 2005 Sun Yat-San University

Relative charge between pixels

Conclusion & ProspectConclusion & Prospect

PSROC, February 2, 2005 Sun Yat-San University

Conclusion:Conclusion: We have developed an electronic system for NuTel experiment.

We developed some methods for calibrating and measuring our hardware system.

We are studying the performance of each component.

Prospect :Prospect : We are planning to go to the high mountains for real testing at the end of this year.

Main Part of DCM Main Part of DCM

PSROC, February 2, 2005 Sun Yat-San University

to another DCM from preamplifier from preamplifier

to DMM calibrationcalibration

cPCI connector

ControlFPGA

ControlFPGA

TriggerFPGA

TriggerFPGA

ADCFPGAADC

FPGAADC

FPGAADC

FPGA

ch. 0ch. 0

ch. 1ch. 1

ch. 2ch. 2

ch. 3ch. 3ch. 4ch. 4ch. 5ch. 5ch. 6ch. 6

ch. 7ch. 7ch. 24ch. 24

ch. 25ch. 25ch. 26ch. 26ch. 27ch. 27ch. 28ch. 28

ch. 31ch. 31

ch. 30ch. 30

ch. 29ch. 29

PLXPCI 9054

PLXPCI 9054

MUX

MUX

MUX

MUX

40 MHzoscillator40 MHz

oscillator

DACDAC

switch

CPLDCPLD

FlashRAMFlashRAM

TTL

LVDS

TTL

LVDS

5V 3.0V5V 3.0V

3.3V 1.8V3.3V 1.8V

+5V

–5VDC–DC

+5V

–5VDC–DC

JTAGJTAG Power controlPower control

FETFET

MUX

MUX

DCM ADC Calibration Measurement DCM ADC Calibration Measurement

PSROC, February 2, 2005 Sun Yat-San University

Inject pulse from DAC into ADC

On average one ADC channel 2mV

LED Light Source LED Light Source

PSROC, February 2, 2005 Sun Yat-San University

Light source are homogenous within 1 to 2 degree.

16

Calculation N of photoelectrons during every Calculation N of photoelectrons during every system clocksystem clock

Cherenkov photons pulse

Preamplifier output

ADC code

Simple difference

ΔA ~Q

Delay due pipeline ADC

System clock (40 MHz)

Delay due calculations

Reconstructedphotons pulse

AN

AN+1

15/16AN

ΔA

Simple difference (AN+1 - AN) will be noisy in hard BG conditions, (ΔA = AN+1 – 15/16 AN) is much more stable

~exp(-t/387ns)exp(-25/387) = 15/16

Data flux in NuTel system Data flux in NuTel system interrupt

interrupt

Trigger decision

Trigger decision

II

MAPMTMAPMT Preamp.Preamp.

II

MAPMTMAPMT Preamp.Preamp.

1632=512 pixels(816) FOV

1632=512 pixels(816) FOV

Daisy-chain of Trigger request

Daisy-chain of Trigger request

System card,LINUX 15 Slave DCM

Master-B DCM

Master-A DCM

interconnectionsfor TIMING COINCIDENCE,System CLOCK,System RESET

Statistics method Statistics method

# of photons coming to PMT, has a Poisson distribution, somean value (M) and RMS (σ0) of the pedestal-subtracted charge

distribution of the PMT are G = M/N = σ02/ M

But the total components of σ:σ2 = {σ1

2 + σ22} + G*M + {σ3

2 + σ42} * M2

noise of electronics without signal (σ1)

noise of PMT gain: signal from photoelectron has the Poisson distribution with 3 (σ2)

•noise of electronics proportional to the signal (σ3*M)

noise due jitter between signal and system clock (σ4*M)

If constant and quadratic components of the noise is smaller than the linear components, G = σ2/M

Using 2 identical telescopes for the Using 2 identical telescopes for the background rejectionbackground rejection

Random Background with NSB flux

Geometrical Trigger:

1 km away from a 1 PeV e- shower

Central pixel passed high-level threshold(HL) & at least N neighboring pixels passed low-level threshold (LL)

Hardware Trigger:• There are geometrical Triggers in any place (direction) at the same time one system clock (25 ns) in both telescopes

On-line Software Trigger:• There are geometrical Triggers in the same place (direction) at the same time in both telescopes

Off-line Hardware Trigger:• More detail data processing, calculation/ searching a possible source on the sky

Data processing in hardware/firmwareData processing in hardware/firmwareMAPMT

Signalsharing

preamplifier

ADC

Calculation Nphotoelectrons

Programmablethresholds

32-channelsTrigger logic

Cycle RAMlike digitaldelay line

32-channelsTrigger logic

Trigger daisy chain

TriggerDecision

logic from the second detector

Buffer RAMlike eventstorage

counterTri

gger

Interrupt to the System card

if 16 events are ready

cPC

I b

us

GeometricalTrigger

Timingcoincidence

Preamp Linearity Preamp Linearity

Feasibility Study of Calibration the NuTel Prototype Detector with Crab NebulaPSROC, February 2, 2005 Sun Yat-San University

Preamp Linearity Preamp Linearity

Feasibility Study of Calibration the NuTel Prototype Detector with Crab NebulaPSROC, February 2, 2005 Sun Yat-San University

Ch.0, HV=650V

y = 0.0005x2 + 2.8447x + 4.7034

R2 = 0.9996

0

100

200

300

400

500

600

700

800

900

0 50 100 150 200 250 300

Y= σ2Ch.0 HV=750V

y = -0.0001x2 + 13.96x + 0.2631

R2 = 0.9999

0

2000

4000

6000

8000

10000

12000

0 100 200 300 400 500 600 700 800

X=M

Ch.0 HV=700V

y = 0.0006x2 + 6.4092x + 15.593

R2 = 0.9996

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 100 200 300 400 500 600 700

X=M

Y= σ2 Y= σ2

X=M

G = 2.84 G = 6.41 G = 13.96

Ch.0, HV=650V

y = 2.9744x + 0.8286

R2 = 0.9994

0

100

200

300

400

500

600

700

800

900

0 50 100 150 200 250 300

Y= σ2Ch.0 HV=700V

y = 6.7454x - 8.2159

R2 = 0.9994

0

500

1000

1500

2000

2500

3000

3500

4000

4500

0 100 200 300 400 500 600 700

Ch.0 HV=750V

y = 13.881x + 7.4397

R2 = 0.9999

0

2000

4000

6000

8000

10000

12000

0 100 200 300 400 500 600 700 800

Y= σ2 Y= σ2

X=M X=M X=M

G = 2.97 G = 6.75 G = 13.88