Status of “Full scanning”

2007/ 03/ 26

Y.Nonoyama

We start scanning new brick “BL112”

• After meeting, we start scanning almost full area of new ECC brick “BL112” with S-UTS 2nd stage.

• So, this is short summary.• Now, finished scanning all plates.• And tried track reconstruction using “NetScan” up

to PL30 from downstream.• Also, I just attempt Momentum measurement usin

g angular method.• Please see this.

Cosmic-Ray (tan<=0.4)• Brick Assembly

• 13m(horizontal)0.19x13x100 = 247• 1h30m(vertical)0.013x90x100 = 117

• De-pack• ~20m(horizontal)0.19x20x100 = 380• max~5h(vertical)0.013x300x100 = 390

• Under Ground(-105m)• 97.39day x ( surface x ~1/100 )

* Flux Measurement @Flab with emulsionvertical - 0.013 /min/cm2

horizontal - 0.19 /min/cm2

Exposure day ( 2581462 trigger (40000trigger/day) ) • event

• 3~5x(2581462/40000) = 200~300• Rock-

1x(2581462/40000)x100 = 6400•*Flux Measurement @MINOS(observed) 3~5ev/day/brick, Rock-1/day/cm2

2position

Develop @Nagoya2times transportation

S-UTS 2nd Stagescanning speed : 33cm2/h (designed 40cm2/h)

Speed : 50 views / secOptics : Tiyoda 50 magnitude lensField of view ： 160 x 160 micron2

Scanning step ： X:135 micron, Y:135 micron

Scanning Area of BL112

5 mm

5 mm115 mm

90 mm

Stage Coordinate

X

Y

Ｂｒｉｃｋ組み立て時の reference edge

103.5 cm2

0

5000

10000

15000

20000

1 1月 日 1 16月 日 1 31月 日 2 15月 日 3 2月 日 3 17月 日 4 1月 日日付

cm面

積（

2 ）

Scanning status

10000cm ２ ／ １ month = 1m2 ／ 1 month

Tot

al S

cann

ing

Are

a (c

m2 )

date

Start : 2007 1/31

Now PL50

Scanning shift

23.6cm2/h から計算すると、１ｍ２／ month = 10000 ／ 24*30=13.8cm2/h

12 h0h 24h

2times changed film in dayScanning time 8~10hours /1film (both side)

0.00001

0.0001

0.001

0.01

0.1

10 10 20 30 40 50 60

Plate No

Dea

d A

rea

Rat

io

stage sidelens side

Scanning Quality

Very beautiful film

Some scratched film

Missing recognized surface

Track Reconstruction

• We tried track reconstruction up to PL29

• Using “NetScan” framework.

NetScan flow• SUTS scanning for both side of film• Base track reconstruction• Align in transportation order

– Reduce tracks reconstructed in transportation order from data set to clean up.(Virtual erasing)

– For BL112, there is two transportation alignment.

• Align in exposure order– ECFSAL is used (Same as DONUT)– ECVTXA is used for vertex hunting.

First Look of NetScan DataThis is angle scatter plot every connected track segments.

2,3segments connected is mainly back ground. But required more than 4segment is significance. Seen NuMI beam angle.

Beautiful Rock MuonNuMI beam angle : y=-0.05Extract around beam angle tracks (-0.1<=x<=0.1 -0.15<=y<=0.05)

Side view

z

yPL29

Sample of 1track

Top view

You can know, not so goodconnection efficiency.Now reconnection going on.

Momentum measurement (angle method)

0X

t

p

K

RMS(i)

p: momentum

: velocity

K : scattering Constant (~ 15MeV/c)

・・・

If angular measurement error = 0 ,

np

p

2

%100

2n : (Number of plates -1) x (2 projections)

t : thickness of material

X0 :Radiation Length

n = 50 p/p = 10 %

Plate by plate signal.

Plot of 1/√<2>

0X

t

p

K

√<2>

mm

mm

p 6.5

115~

X0(Pb)=5.6mm

p = 6 x 1/ <2>

There is good correlation ofx-projection vs y-projection. So, not so bat connection.

Nseg>=4 Nseg>=8

Nseg>=12 Nseg>=16

This plot shows inverse number of RMS(difference angle) 1plate by 1plate.All angle

Summary and Future

• We start “full area scanning” systematically. and starting non-bias neutrino physics.

• But offline analysis needed more developed.– Up connection efficiency…– Vertex hunting…

• And good news, I found electron shower but it is accident not systematically.

Please see next page…– e event … ??

Pretty electron shower

Happen to find electron shower in BL112