Time stamping for Emulsion Tracks with Gyaku Data Base method Y.Nonoyama

Introduction Last autumn, I showed the GyakuDataBase method in Matsumoto. Now, I’m developing. I try time stamping systematically. So, I’m looking for good separation parameter. Today, I show a part of it.

Gyaku Data Base Emulsion track match no match allowance match Emulsion track extension down stream. Look for SFT hits on the Emul track ?? Allowance : +- (1mm + 3mrad  z axis) SFT plane alignment + angle measurement error (and scattering error) match SFT = 10layer (x,y-projection), 2layer (u-projection) beam

Sample 1 : BL040 No x-ray

BL040 PL1-2 Alignment in MINOS hallAlignment in Transportation 8 x 7 cm 2 SUTS scan

Alignment in TransportationAlignment in MINOS hall

BL040 PL1-2 After virtual erase

BL040 PL1-2 Peak 2 Peak 1

BL040 PL1-2 Peak 1Peak 2

SFT matching (903 tracks)  x vs  y Residual from nominal Using SFT reconstructed tracks

After alignment between ECC with SFT xx yy  x  y mm rad

Select Scan Back tracks with GyakuDataBase I selected 165tracks matching with SFT trigger. I thought these are from Interaction. Checked again and selected good match 31tracks with SFT trigger from them. And, best matched tracks are 20 in 31tracks. –13 are Rock Muon type. –7 are Interaction type.

How decide best match ? Important point, there is SFT hits directory below plane of ECC target. If matching is real, SFT hits exist far 1~2 fibers. Also It’s same low momentum particle. Because no material between ECC target to directory below SFT plane. point

Residual of Emulsion track to hits of directory below plane This showed residual. extension emulsion track to below SFT plane. Select tracks matching with SFT trigger as Rock Muon type by eyes. y x x y 2 3 mm If matching is real, its residual will be into 500  m. mm

31tracks scan back result SFT trigger type Scan back result PenetratestopNot yet Rock Muon Interaction0437 Unknown0145 Not so good2417

79 0.0,

, 0.4

,

, , -0.1

penetrate 281

0.2 penetrate 818

Sample2 : BF021 * x-ray

Select scan back track like BL040 and Scan back result SFT trigger type Follow up result PenetrateStop Rock Muon707 Interaction022

0.0, , -0.2

-0.3, , 0.1

PL 43 I.P. 1.5  m

summary Now looking for good separation parameter. One is below SFT plane hits. This selection power is very good. Bud SFT link efficiency is effected by SFT efficiency. So, other selection parameter will be needed for efficiency.