Wide Field Scanning

K. MorishimaNagoya University

Aim

Speed up of CS scanning

Method

・ wide field optics・ enlarge grains + swell emulsion

test optics

F.O.V = 154 x 115 micron2

pixel scale

x = 0.30 micron/pixel

　　　 Y = 0.24 micron/pixel

F.O.V = 317 x 240 micron2

pixel scale

x = 0.62 micron/pixel

Y = 0.50 micron/pixel

standard wide field

Tiyoda x50 oil immersion lens (N.A. = 0.85, WD = 1.2mm)

Nikon CFI Plan x50 oil immersion plane lens (N.A. = 0.90, WD = 0.4mm) + x0.5 tube lens (for format conversion) (Nikon) + x0.7 relay lens (Tiyoda)

sensor size½ inch

scanning test sample (double refresh exposed cosmic@ Gran Sasso CS facility)

cut

1. In water to remove glicelin2. gold deposit development for enlarging grains by Kubota3. swell emulsion by Naganawa

reference

30mm 92.5mm

50mm

Normal Development film @ GS

picture1 ( normal )

Thickness = 40 micron

picture2 ( enlarged )( gold deposit development )

Thickness = 60 micron

close up grain

0.3 x 0.3 square micrometer

S-UTS,UTS pixel size is about 0.3 micron

On a focal plane

0.5 micron0.8 micron

focal depth of enlarged grain

Grain size is larger , focal depth of grain is lager

Swell emulsion

The number of grains increases on a focal plane

Back ground tracks increases

Relation between focal depth and grain size

normal enlargedenlarged + swelled

grain

focal plane

focal depth of grain

difference of film

normal enlarged ratio

grain size (micron) 5.0 8.0 (x1.6)

F.D. ( / 1000mic3) 4.3+-0.4 4.6+-0.3 (~x1)

thickness (micron) 40 60 (x1.5)

Scanning test

normal

30mm 92.5mm

50mm

enlarged + swelled

1. Pick up prediction tracks (pl3-pl4-pl6)2. Search pl5 for microtracks window : dx,dy < +-10micron dthx,dthy < +-100mrad

pl3

4

5

6Exist or not

Pl 05

optics emulsionA. Standard – normalB. Wide field – normalC. Wide field – enlarged + swelled

Scan area : 1cm2

A. UTS　 standard optics+ normal film

Bg : /(100x100mic2)x/(100x100/mrad2)

A. micro track angular resolution

X

Y

14 mrad

13 mrad

B. Wide Field + normal film

Bg : /(100x100mic2)x/(100x100/mrad2)

B. micro track angular resolution

X

Y

21 mrad

18 mrad

C. Wide Field + enlarged grain + swelled emulsion

film

Bg : /(100x100mic2)x/(100x100/mrad2)

C. micro track angular resolution

X

Y

27 mrad

24 mrad

comparison of efficiency

Grain size efficiency Noise

Standard 1 normal 93.1+-1.4 0.1

wide field 2 normal 92.8+-1.4 0.5

wide field 2 enlarged 95.3+-1.1 0.9

X Y1 : 0.30micron/pixel , 0.24micron/pixel2 : 0.62micron/pixel , 0.50micron/pixel