gempix detectors as hadron therapy beam monitors and radioactive waste detectors
DESCRIPTION
F.Murtas INFN-CERN-Ardent J. Alozy, E.Frojdh, S . George , M. Silari CERN. GEMPIX detectors as hadron therapy beam monitors and radioactive waste detectors. GEMPIX construction Beam monitor for H adrotherapy GEMPIX for Radioactive Waste Conclusions. Gempix Detector . - PowerPoint PPT PresentationTRANSCRIPT
J. Alozy, S. George , F.Murtas , M. Silari 1CERN 17-06-2014
GEMPIX detectors as hadron therapy beam monitors and radioactive
waste detectors
• GEMPIX construction• Beam monitor for Hadrotherapy• GEMPIX for Radioactive Waste• Conclusions
F.Murtas INFN-CERN-ArdentJ. Alozy, E.Frojdh, S. George , M. Silari CERN
J. Alozy, S. George , F.Murtas , M. Silari 2CERN 17-06-2014
Gempix Detector
Side view
Quad medipix board
The detector has two main parts :- The quad medipix without silicon sensors- The triple gem detector with HV filters and connector
New HV GEM board
J. Alozy, S. George , F.Murtas , M. Silari 3CERN 17-06-2014
Gem foils and frames A new GEM layout has been designedActive area of 28x28 mm2 The electordes path have been designed to avoid the medipix wire bonding.Produced by Rui De Oliveira.
New frames were designed 10x10 cm2
to fit the holes of the Quadmedipix board
5 different thickness (from 1 to 5 mm)
Wire bonding position
J. Alozy, S. George , F.Murtas , M. Silari 4CERN 17-06-2014
Assembling the GEM foils
The three GEM foils are assembled on top of HV GEM board
J. Alozy, S. George , F.Murtas , M. Silari 5CERN 17-06-2014
Final detector
J. Alozy, S. George , F.Murtas , M. Silari 6CERN 17-06-2014
Head on detector
Gas flux AR CO2 or AR CO2 CF4
The anode is a quad naked without silicon sensor :The active area is 9 cm2
Triple GEMMylar window
Particles to be analysed
HVGEM Console
FITPIX Console
HV
FITPIX
J. Alozy, S. George , F.Murtas , M. Silari 7CERN 17-06-2014
A small TPC
Gas fluxThe anode is a quad medipix without silicon sensor:The active area is 9 cm2
The particle track is analysed with 512 pixel in length of 3 cm
This detector could be used also as Tissue Equivalent Proportional Chamber The track path is equivalent to 30 microns of tissue … with 17 samples/microns
Triple GEM
Kapton windowParticles to be analysed
Length analysed
J. Alozy, S. George , F.Murtas , M. Silari 8CERN 17-06-2014
GEMPIX Detectors
Head-on version(4 detectors)
Side-on version(2 detectors )
HV Connector
MedipixDAQ box
J. Alozy, S. George , F.Murtas , M. Silari 9CERN 17-06-2014
Measurements atCNAO (Pavia - Italy)Carbon ion beam
at 480 Mev/nucleon
J. Alozy, S. George , F.Murtas , M. Silari 10CERN 17-06-2014
MeasurementsBeam : 480 MeV/A Carbon Ion
Measurements in air
Measurements in water phantom :23 different depths throughout water phantomEach position given spot 5.108 carbon ion treatment (clinical treatment intensities)
Frame length = 1ms, gas = ArCO2, gain = 750 V (~0.43 keV/TOT - Proper calibration awaits the return of the detector from CNAO RP).
J. Alozy, S. George , F.Murtas , M. Silari 11CERN 17-06-2014
Mylar windowGas in/out
Fitpix Readout
External HV (HVGEM)
GEMPIX at CNAO (Pavia)
J. Alozy, S. George , F.Murtas , M. Silari 12CERN 17-06-2014
GEMPIX as a Beam Monitor
480 MeV/A carbon ions, 10 ms frame, ASIC in Medipix (particle counting) Mode, IKrum = 5
Counts
Single Carbon Ion
Other particle
J. Alozy, S. George , F.Murtas , M. Silari 13CERN 17-06-2014
The overall beam shape is clearly visible
Beam profile
As number of hits As energy released
J. Alozy, S. George , F.Murtas , M. Silari 14CERN 17-06-2014
Gempix Linearity
Number of counts per spills
Time (s)
J. Alozy, S. George , F.Murtas , M. Silari 15CERN 17-06-2014
Phantom used at CNAO
Bragg Peak finder at CNAO
Thin WindowGempix
Stepper Motor
Several measurement of energy deposition along the beam (5x108 Carbon ions per 10 spills)
J. Alozy, S. George , F.Murtas , M. Silari 16CERN 17-06-2014
Energy deposition is ~0.43 keV/TOT Spot width here is sigma of gaussian (FWHM = 2.3 sigma)
Depth profile and beam dimension
J. Alozy, S. George , F.Murtas , M. Silari 17CERN 17-06-2014
Linear Log 3D reconstruction
Energy deposition: 3D reconstruction
This part (neutrons and gammas) could be analyzed with really high resolution
J. Alozy, S. George , F.Murtas , M. Silari 18CERN 17-06-2014
Single Event Upset
Depth = 124 mm (in bragg peak), ~0.43 keV/Count (9.6 MHz, TOT mode), IKrum = 1, 1ms frame
SEU Events
J. Alozy, S. George , F.Murtas , M. Silari 19CERN 17-06-2014
No Cfg Resets
Reset at start
Reset/10 frames
Reset every frame
Reconfiguring
J. Alozy, S. George , F.Murtas , M. Silari 20CERN 17-06-2014
Radioactive Waste :a detector for 55Fe
J. Alozy, S. George , F.Murtas , M. Silari 21CERN 17-06-2014
Sample Preparation
Fraiseuse DECKEL FP4M for powder productionreducing the 60CO background
Boxes supplied by SMIPA s.r.lDimension: 38x38x4 mm3
(now 38x38x8 mm3)Weight: 3.951 ± 0.15%
Measurements for Fe-55 concentration with GEMPIX ,two different configuration :Drift gap 11 mmDrift gap 3 mm
Support conceived for measurements with samples and calibration sources
J. Alozy, S. George , F.Murtas , M. Silari 22CERN 17-06-2014
Radioactive waste: 55Fe
1 sec radioactive source
100s counts
J. Alozy, S. George , F.Murtas , M. Silari 23CERN 17-06-2014
X-ray candidates
Bck
Signal vs Background
Gas AR CO2CF4Gate: 1 sHV 1200 VGas flux: 3.5 l/h
Clk: 24Ikrum: 5Polarization: -
J. Alozy, S. George , F.Murtas , M. Silari 24CERN 17-06-2014
Cluster parameters measurements
Cluster type Cluster volume Inner size
Border size Size Size y vs size x
55Fe
60Co
55Fe
60Co
55Fe
60Co
55Fe
60Co
55Fe
60Co
J. Alozy, S. George , F.Murtas , M. Silari 25CERN 17-06-2014
Online analysis
Once that the calibration values are set in the Python script, an online analysis can be performed
Number of X-Rays measured in 1000 sec
Number of big blob
Cut on sizeCut on charge
J. Alozy, S. George , F.Murtas , M. Silari 26CERN 17-06-2014
Drift 3 mm vs drift 11 mm
Attenuation length 2.91 cm
Theory: 11 mm/ 3 mm = 2.6
Measurements:11 mm/ 3 mm = 2.7
Waiting the measurements from certificated company for the final calibration
J. Alozy, S. George , F.Murtas , M. Silari 27CERN 17-06-2014
Summary Six GEMpix detectors have been built and they show good performances
from single particle detections to high intensity beam monitor
Really good cluster analysis is possible thanks to the Fitpix software pakage
Software tools and detector tuning are still needed for the cluster analysis in gas (dE/dX, particle id, 3D track reconstruction....)
The detector could be easily improved with Timepix3 chips
Other applications and measurements are scheduled for next months Monitor for burning plasma (KSTAR - PETAL) Measurements for micro and nano dosimetry with tissue equivalent gasMonitor for gamma radiotherapy