RivelatoreRivelatore a a siliciosilicio

50-60 pACorrente di fuga a 22º C

~25 VTensione di svuotamento

765 mSpessore inattivo di Si

100 mPasso fra strip

400Numero di strip

10 mmLunghezza strip

300 mSpessore

ValoreParametro

EfficienzaEfficienza del del rivelatorerivelatore

� Calcolo dell’efficienza– FotoneX assorbito se interagisce

nelle regioni passive– FotoneX rivelato se subisce

effetto fotoelettrico nella regioneattiva

� GeometriaFront– Strip ortogonali al fascio– 70 µm di Al (schermo e.m.)

� Geometry Edge-on– Strip paralleleal fascio– 765 µm di Si inattivo– Efficienzamiglioreper E > 18

keV

• Fully parallel signal processing for all channels• Binary architecture for readout electronics

� 1 bit information (yes/no) is extracted from each strip• Data from each channel must be stored in the local buffer for the whole measurement period

• Fully parallel signal processing for all channels• Binary architecture for readout electronics

� 1 bit information (yes/no) is extracted from each strip• Data from each channel must be stored in the local buffer for the whole measurement period

data, control

Silicon str ip detector Integrated circuit

100 µµµµm

current pulses

X-rays

PC

N. I . I /O cards PCIN. I . I /O cards PCI --DIODIO--96 96 and DAQCardand DAQCard--DIODIO--2424

SistemaSistema a a conteggioconteggio didi fotonefotonesingolosingolo

RivelatoreRivelatore completocompleto

PCB:- Rivelatoreda400 strip- Adattatoredi passo- 6 chip RX64

� 384 canali equipaggiati- Connettoreverso schedaDAQ2 prototipi:a) 6 x Single threshold RX64b) 6 x Dual threshold RX64

PCB:- Rivelatoreda400 strip- Adattatoredi passo- 6 chip RX64

� 384 canali equipaggiati- Connettoreverso schedaDAQ2 prototipi:a) 6 x Single threshold RX64b) 6 x Dual threshold RX64

150

100

50

0

Co

un

ts

500400300200100

Threshold (mV)

Source Am+Rb target Source Am+Mo target Source Am+Ag target Tube+Cu target Tube+Ge target Tube+Mo target Tube+Ag target Tube+Sn target

Cu K αααα

Mo K ααααGe K αααα

Rb K αααα

Ag K αααα

Sn Kββββ

Ag Kββββ

Mo Kββββ

Sn K αααα

164 el.141 el.64.6 internal calib.

182 el.151 el.63.7 X-ray tube

179 el.154 el.62.8 241Am source

ENC50ENC30

Improved ampl. setting

GAIN

µµµµV/el.6 x RX64 + fanout + detector, Tp=0.5 s

241241Am Am sourcesource withwith rotaryrotary target target holderholder ((targetstargets: Cu, : Cu, RbRb, Mo, , Mo, AgAg, , BaBa))CuCu--anodeanode XX--rayray tube tube withwith fluorescencefluorescence targetstargets (Cu, (Cu, GeGe, Mo, , Mo, AgAg, , SnSn))

CalibrazioneCalibrazione energeticaenergetica

15

10

5

0

pixe

ls

3002001000pixels

C o n c(I) = 370 m g /m l M easu rem en t S im u la tio n

ln[c

ount

(E=3

5.5K

ev)]

- ln

[cou

nt(E

=31.

5Kev

)]

S trip N u m b er

15

10

5

0

pixe

ls

3002001000pixels

Co nc(I) = 370 m g/m l E = 31 .5 K eV

M easurem en t Sim u latio n

Co

unt

s / M

ax.C

oun

ts

S trip N um b er

E = 31.5 E = 31.5 keVkeV

15

10

5

0

pixe

ls

3002001000pixels

0 50 100 150 200 250 300 350

0,0

0 ,2

0 ,4

0 ,6

0 ,8

1 ,0

S tr ip N u m be r

M easu re m en t S im u la tio n

C o nc (I) = 3 70 m g /m l E = 3 5.5 K e V

Cou

nts

/ Max

.Cou

nts

E = 35.5 keV

( ) ( )5.315.35 lnln NN −logarithmic subtraction

Phantom structure not

visible in final image

Risultati del test Risultati del test angiograficoangiografico

15

10

5

0

pixe

ls

3002001000pixels

ConcConc = 370 mg / ml= 370 mg / ml

15

10

5

0

pixe

ls

3002001000pixels

ConcConc = 92.5 mg / ml= 92.5 mg / ml

15

10

5

0

pixe

ls

3002001000pixels

ConcConc = 23.1 mg / ml= 23.1 mg / ml

100

80

60

40

20

0

SN

R

4003002001000Concentrazione (mg/ml)

cavità 4 teor. cavità 4 cavità 3 teor. cavità 3 cavità 2 teor. cavità 2 cavità 1 teor. cavità 1

Possible decrease of iodine concentration keeping the same rad. dose

Risultati del test Risultati del test angiograficoangiografico (2)(2)

Resulting Resulting projected projected

image for the image for the angle 35.5angle 35.5°°

that makes the that makes the contrast contrast

between between water water and PMMA and PMMA

vanishvanish

32 32 keVkeV

Resulting Resulting projected projected simulated simulated

image for the image for the angle angle 4747°°that makes that makes the contrast the contrast

between between PMMA PMMA and and PE PE vanishvanish

MeasuredMeasured

Data Data

SimulatedSimulated

DataData

16 16 keVkeV Projected images Projected images

-- 3 3 componentcomponent phantomphantom::PMMA+PE+WaterPMMA+PE+Water-- 3 3 tissuestissues simulatedsimulated::Glandular+Adipose+CancerGlandular+Adipose+Cancer

Risultati del test Risultati del test mammograficomammografico