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 2 nd 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 using 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 with emulsion vertical /min/cm 2 horizontal /min/cm 2 Exposure  day ( trigger (40000trigger/day) ) event 3~5x( /40000 ) = 200~300 Rock-  1x( /40000)x100 = 6400 *Flux  3~5ev/day/brick, Rock-  1/day/cm 2 2position 2times transportation

S-UTS 2 nd Stage scanning speed : 33cm 2 /h (designed 40cm 2 /h) Speed : 50 views / sec Optics: Tiyoda 50 magnitude lens Field of view ： 160 x 160 micron 2 Scanning step ： X:135 micron, Y:135 micron

Scanning Area of BL112 5 mm 115 mm 90 mm Stage Coordinate X Y Ｂｒｉｃｋ組み立て時の reference edge cm 2

Scanning status 10000cm ２ ／ １ month = 1m 2 ／ 1 month Total Scanning Area (cm 2 ) date Start : /31 Now PL50

Scanning shift 23.6cm2/h から計算すると、１ｍ２／ month = ／ 24*30=13.8cm2/h 12 h 0h 24h 2times changed film in day Scanning time 8~10hours /1film (both 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 Data This 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 Muon NuMI beam angle :  y =-0.05 Extract around beam angle tracks (-0.1<=  x <=0.1  -0.15<=  y <=0.05) Side view z y PL29 Sample of 1track Top view You can know, not so good connection efficiency. Now reconnection going on.

Momentum measurement (angle method) RMS(  i ) p: momentum  : velocity K : scattering Constant (~ 15MeV/c) ・・ ・ If angular measurement error = 0, 2n : (Number of plates -1) x (2 projections) t : thickness of material X 0 :Radiation Length n = 50   p/p = 10 % Plate by plate signal.

Plot of 1/√ √ X 0 (Pb)=5.6mm p  = 6 x 1/ There is good correlation of x-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