parametro valore spessore 300 m - uniupo.itpeople.unipmn.it/ramello/labfbm-2005-6.pdf · • data...
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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
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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
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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
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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
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ConcConc = 370 mg / ml= 370 mg / ml
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ConcConc = 92.5 mg / ml= 92.5 mg / ml
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ConcConc = 23.1 mg / ml= 23.1 mg / ml
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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