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III ARDENT Annual Workshop

29/09-02/10/2014IBA Dosimetry

Francesca BiselloESR 10

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OutlineResearch Activities

ConferencesTraining and Secondments

I. Research Activities

II. Conferences

III. Trainings and Secondments

Outline

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Research Activities

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Dosepix Characterization

General overview

OutlineResearch Activities

ConferencesTraining and Secondments

Dosepix detector as Quality Assurance tool in diagnostics

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Counts

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OutlineResearch Activities

ConferencesTraining and Secondments

Dosepix Characterization

kVp-meter in mammography

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OutlineResearch Activities

ConferencesTraining and Secondments

October 2013 – October 2014:

Dosepix as kVp-meter in mammographyRadiation Tolerance studiesTemperature characterization

Dosepix Characterization

Sum up of activities

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OutlineResearch Activities

ConferencesTraining and Secondments

Dosepix CharacterizationkVp-meter in mammography

o Image quality and dose depend on the xRay tube voltage

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Tube setting: 30 kV, 20 mAs

Mo-Mo

Big Pixels

Tube setting: 30 kV, 20 mAs

Mo-Mo

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OutlineResearch Activities

ConferencesTraining and Secondments

Dosepix CharacterizationkVp-meter in mammography

o kVp: fitting the end point of the spectrum

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f(x) = 0.905925196214262 x + 3.35983643787807R² = 0.993008054945356

kVp MagicMax (kV)

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Additional filtration: 0.3mm CuCounts/big pixel/s: 1.5 · 104 Hz [ count rate without filtration : 5· 104 Hz ]

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OutlineResearch Activities

ConferencesTraining and Secondments

Dosepix Characterization

RadiationTolerance studies

10-28/02/2014Secondment at CERNRadiation Tolerance Studies

Measurement Session:Accumulated dose for the test: 5 kGy in step of 200 Gy Tube settings: 40 kV, 2 mA dose rate 4.83 Gy/min

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OutlineResearch Activities

ConferencesTraining and Secondments

Dosepix CharacterizationRadiation Tolerance studies

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OutlineResearch Activities

ConferencesTraining and Secondments

Dosepix CharacterizationRadiation Tolerance studies

Poster Presention IEEE 2014, 8-15 November 2014 “Investigation on the radiation tolerance of Dosepix detector” F. Bisello, W.S. Wong , E.Frojdh , J.Alozy I. Ritter, A.Zang, M. Campbell, J.C.Celi, G.Anton and T.Michel

o Deeper analysis of effect around mammographic energieso Investigations in damages in the sensor or in the chip

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OutlineResearch Activities

ConferencesTraining and Secondments

Dosepix Characterization

Temperature Characterization

First Measurement Session: CERN (secondment)Addidtiona Investigations: IBA Dosimetry

Measurement Session:Range required by the regulation: 15°- 35 °CInstability < 1%

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OutlineResearch Activities

ConferencesTraining and Secondments

Dosepix CharacterizationTemperature Characterization

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OutlineResearch Activities

ConferencesTraining and Secondments

Dosepix CharacterizationTemperature Characterization

Source of instability (I):PLL circuit

Source of instability (II):Bias current of initial gain stage of

the discriminator

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OutlineResearch Activities

ConferencesTraining and Secondments

Dosepix CharacterizationTemperature Characterization

Next steps:

o Evaluate the possibility to bypass the PLL circuit

o Find other more stable configurations for the analog front end

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OutlineResearch Activities

ConferencesTraining and Secondments

Other Activities

SFD diodes

Machine and Plan QASmall Field external Radiotherapy

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OutlineResearch Activities

ConferencesTraining and Secondments

Other ActivitiesSFD diodes

Studies on sensitivity dependence from:

• Dose• Dose per pulse• Dose rate

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OutlineResearch Activities

ConferencesTraining and Secondments

Other ActivitiesSFD diodes

Oral Presentation, RESMDD14, 8-10 October 2014 “Development of silicon monolithic arrays for dosimetry in external beam radiotherapy”

F. Bisello, M. Bucciolini, M. Bruzzi, D. Menichelli, M. Scaringella, C. Talamonti, M. Zani1,2

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Conference

Trainings

Secondments

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OutlineResearch Activities

ConferencesTraining and Secondments

Conferences 2014

DPG Mainz, 25th March 2014Oral Presentation “Characterization of the Dosepix detector under clinical conditions ”

RESMDD Florence, 8-10 October 2014Oral Presentation “Development of silicon monolithic arrays for dosimetry in external beam radiotherapy”

IEEE 2014 Seattle, 8-15 November 2014Poster Presentation “Investigation on the radiation tolerance of Dosepix detector”

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OutlineResearch Activities

ConferencesTraining and Secondments

Planned Training and Secondments

Business and Administration training, ST Microelectronics

Secondment at the UPENN University Hospital, Phyladelphia (tentative: 16-28 November 2014):

Measurements on plan QA with silicon monolithic array

Trainings on clinical quality assurance routine (to be defined)

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Thank you very much for your attention