we are now working with 2 microscope: 1st microscope official setup: micos stage nikon optics and...

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We are now working with 2 microscope: 1st Microscope Official setup: MICOS stage NIkON optics and illuminator DALSA camera cad-4

Recently several hardware problems with this setup:• fault counting on stage encoders: compromised repeatability of measurements (Now fixed) • motion instability of the stage (5-20 micron) (Unresolved) • Image quality of camera seriously degraded (Unresolved)

2nd Microscope Prototype setup:

MICOS stage

ZEISS optics (40X) and fiber optic illumination

Custom CMOS camera interfaced to Genesis (Thanks to Salerno group for the Genesis boards)

Microscope used mainly for test (see Gabriele talk)fine tuning not yet concludedNot ready for the ACQ

• 8 emulsions sheets after 1.6 cm of Lead (from 25 to 32) • 7 angles

• Tracks density: 5-7 /mm2 (pions and muons)

• 1.1 X 1.1 cm2 scanned surface on each emulsion sheet

Due to HD problems results are relative to Dec presentation in Salerno

Top : 352 microtracks/view

Bottom : 302 microtracks/view

Top microtracks in fiducial marks coordinates

Vertigo Scan Configuration : 20 Layers over 44 microns

Focus lock on center level (2-3 levels are “empty”)

Base tracks are uniformly distributed in the scanned area:

253 tracks/mm2 /|θ|<0.6 rad

How we select the signal:

•Rectangular cut |θx| < 0.72 && | θy+0.007|< 0.015

•Gaussian fits over a flat background

• each peak is selected inside 3σ

Total signal = 2269 Background = 142

Signal :

27 tracks/mm2

Outside the beam angular region

signal

We performed alignment and tracking with FEDRA and AlphaOmega, the results are

comparable .

415 tracks with 8 segments are reconstructed

= (84±2)% overall

Thanks to Napoli and Salerno Labs, we measured the plate #29:

• 1cm2 measured twice @ Napoli: signal tracks inside 3σ (NA-1 e NA-2)

• 1cm2 measured twice @ Salerno: signal tracks inside 3σ (SA-1 e SA-2)NA-1

SA-2SA-1

NA-2

Cnapoli

Csalerno

Tracks measured

twice @ Napoli

OR

twice @ Salerno

Cnapoli

Csalerno

Referene Tracks

256230

296

326 310

238

223

74% of prediction tracks has been measured in Bologna

Our guess: part of inefficiency is due to a non exhaustive trigger list.

We continue to use a MC approach to improve this point.

Data and MC tracks are not directly comparable: MC is used as an external tool to validate the method.

An additional code has been written to find out the best trigger list.

An interface to use Tracking has been written

(fd = 2.2) (fd = 2.2) focal depth in focal depth in mm(dens = 30.) (dens = 30.) grain density in grains/100 grain density in grains/100 mm(fog = 5.) (fog = 5.) fog density in grains/1000 fog density in grains/1000 mm33

(et = 44.) (et = 44.) emulsion nominal thickness in emulsion nominal thickness in mm(srink = 1.1) (srink = 1.1) srinkagesrinkage(nl = 20) (nl = 20) number of levelsnumber of levels(etdaq = 44) (etdaq = 44) emulsion thickness (DAQ parameter)emulsion thickness (DAQ parameter)(sigsm = 0.06) (sigsm = 0.06) radial smearing of grains in radial smearing of grains in mm(surfsm = 0.8) (surfsm = 0.8) focusing smearing in focusing smearing in mm(ccdsm = 0.3) (ccdsm = 0.3) CCD readout resolution in CCD readout resolution in mm(aview = 240.) (aview = 240.) view side in umview side in um

Parameters used in the simulation

FogTrackGrains

Track generation (Fluka, Geant 4)

Grain generation Fog grain generation

ACQ simulation: Levels & Clusters

Output microtracks

Set of ValidatedReal tracks

Trial Triggerlist

Trigger Optimization

code

Best Triggerlist

Complete setof MC tracks

Trigger Optimization

code

Best Triggerlist

GrainGeneration

code

=0.98 =0.95

The comprehension of the efficiency problem is still incomplete. In particular:

At the level of the microtrack;At the level of microtrack linking.

Work in progress on the background evaluation. Preliminary results are encouraging.

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