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Papers by Agostino Tartari

Radiation Physics and Chemistry, 1999

ABSTRACT Measurements of molecular cross sections of coherently scattered photons were obtained b... more ABSTRACT Measurements of molecular cross sections of coherently scattered photons were obtained by means of powder diffraction data analysis in the interval χ=0–6.4 nm−1 (χ=sin(θ/2)/λ; where θ is the scattering angle and λ the incident wavelength in units of nm). Accurate correction procedures were applied to the raw diffraction data. Data for fat and PMMA (polymethyl methacrylate)—reported in a previous analysis (Tartari A, Casnati E, Bonifazzi C, Baraldi C, 1997b. Phys. Med. Biol. 42, 2551–2560.—were found to agree quite well when compared to the results obtained with different quality of beams and analysis techniques. Investigation on bony tissue is presented for the first time, and a simple model has been carried out in order to segment the mineral and non-mineral components. Finally, a basic set of curves for the linear differential scattering coefficient is proposed in order to simulate photons scattering by tissue in terms of linear combination of such curves.


Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, 2004

Advanced Monte Carlo For Radiation Physics Particle Transport Simulation and Applications, 2001

Journal of Physics B Atomic Molecular and Optical Physics

Coherent scattering cross sections of 59.54-keV photons on target foils of 64 Gd, 66 Dy, 68 Er, 7... more Coherent scattering cross sections of 59.54-keV photons on target foils of 64 Gd, 66 Dy, 68 Er, 70 Yb, 72 Hf, and 73 Ta at 60°, 90°, and 120°have been measured to provide information on the region of K anomalous elastic scattering. The results are compared with the values calculated by the second perturbative order S matrix and by two procedures based on the form-factor approximation corrected by the anomalous scattering factors. Agreement of the S matrix values is very satisfactory, on the whole, and that of the values given by the form-factor approximations is fairly good.

La recente crisi petrolifera ha in vario modo incrementato l'interesse per la produzione di energ... more La recente crisi petrolifera ha in vario modo incrementato l'interesse per la produzione di energia elettrica tramite fonti alternative. Una possibilità in tale direzione potrebbe essere data dalla reazione nucleare protone-Boro realizzata con l'impiego di macchine tipo Plasma Focus, con le quali e' possibile il raggiungimento di temperature superiori ai 10 9 gradi K, in connessione con l'impiego di tecniche di conversione diretta dell'energia con rendimenti del 60-70%.

X-Ray Spectrometry, 2015

A plasma focus device, devoted to the study of a possible application to the radiotherapy treatme... more A plasma focus device, devoted to the study of a possible application to the radiotherapy treatment of malignant cells, has been recently put into operation. The low-energy (up to 200 keV) X-rays are produced by conversion of the electron beam generated by the device during the pinch phase. The X-ray spectrum has already been fully characterized, and an initial campaign of irradiation of specific cell cultures has been completed. At present, the links between the operational parameters of the actual device, the beam intensity, and the cell irradiation effects are being analyzed, trying to evaluate the advantage of the very high dose rate that can be delivered, of the order of several Gy in a few tens of nanoseconds. Preliminary results on radiobiological effectiveness are presented and discussed.

Lecture Notes in Control and Information Sciences, 1996

ABSTRACT We present a regularization technique for solving inverse ill-posed problems which arise... more ABSTRACT We present a regularization technique for solving inverse ill-posed problems which arise in many fields of applied optics and electrodynamics when one has to deal with restoration of images. Numerical results for electron scattering and free-electron-laser data are shown and the problem of reconstructing a planar image from its line integrals in computerized Compton and X-ray diffraction tomographies is addressed.

2000 IEEE Nuclear Science Symposium. Conference Record (Cat. No.00CH37149), 2000

ABSTRACT The use of a dedicated gamma camera for scintimammography with breast under compression ... more ABSTRACT The use of a dedicated gamma camera for scintimammography with breast under compression can improve the detection of sub centimeter cancers. Unfortunately, detectors based on PSPMT show a poor energy resolution that would not be able to discriminate tumors in the posterior portion of the breast where the scattering of photons, coming from the chest, is particularly prominent. In this paper we introduce the modified truncated SVD (mTSVD) based deconvolution as a numerical approach to enhance the energy resolution. Tc99m calibration spectra were used to numerically describe the detector response function; the degree of ill-posedness of the numerical problem was carefully study in order to perform the deconvolution of ROI, in different breast position, by a unique response function. Eight ROI spectra from breast phantom and two from a patient study were analyzed, respectively. For each or them the energy resolution, after the deconvolution, was about 1.7 times improved. The results shown that the mTSVD based deconvolution can represent an useful tool to increase the energy resolution in scintimammography, and to improve the image quality by further suppression of the Compton scattering

Charged and Neutral Particles Channeling Phenomena - Channeling 2008 - Proceedings of the 51st Workshop of the INFN ELOISATRON Project, 2010

Within the seventh framework programme of the European Union, a threeyear project called Labsync ... more Within the seventh framework programme of the European Union, a threeyear project called Labsync has been recently funded with the aim to design a complete small facility around the MIRRORCLE source, a laboratory sized commercial synchrotron developed in Japan. The medical physics group of Ferrara University is one of the seven partners of the Labsync consortium. Its main task is the design and characterization of the medical beamline. In this contribution a Monte Carlo simulation of the x-ray spectrum obtained by bremsstrahlung interaction of the electron beam with tiny targets are presented. Furthermore, theoretical results of PXR are shown in terms of x-ray flux and beam geometry.

ABSTRACT The authors investigate a technique for the characterisation of biological tissues, base... more ABSTRACT The authors investigate a technique for the characterisation of biological tissues, based on energy analysis of Compton scattered photons. The incident beam consists of 59.54 keV photons and a backscatter geometry is used. Compared to the technique based on the ratio of photons coherently scattered due to the Rayleigh effect and those incoherently scattered due to the Compton effect, the present technique provides similar results for mineral content evaluation, with an error lower than 1%. However it allows the determination of fat content in a soft tissue matrix - even in the cases in which the Rayleigh peaks is not measurable - although the error can rise up to 3%.

IEEE Symposium Conference Record Nuclear Science 2004., 2004

The use of dedicated gamma camera, with high intrinsic spatial resolution can raise the detection... more The use of dedicated gamma camera, with high intrinsic spatial resolution can raise the detection of sub centimeter cancers in Scintimammography. The recent development of new gamma imagers based on scintillation array with high spatial resolution has strongly improved the SNR of the resulting images; however, Compton scattering contamination is the main drawback in Scintimammography, since it limits the sensitivity

Advanced Monte Carlo for Radiation Physics, Particle Transport Simulation and Applications, 2001

Radiation Physics and Chemistry, 1999

ABSTRACT Measurements of molecular cross sections of coherently scattered photons were obtained b... more ABSTRACT Measurements of molecular cross sections of coherently scattered photons were obtained by means of powder diffraction data analysis in the interval χ=0–6.4 nm−1 (χ=sin(θ/2)/λ; where θ is the scattering angle and λ the incident wavelength in units of nm). Accurate correction procedures were applied to the raw diffraction data. Data for fat and PMMA (polymethyl methacrylate)—reported in a previous analysis (Tartari A, Casnati E, Bonifazzi C, Baraldi C, 1997b. Phys. Med. Biol. 42, 2551–2560.—were found to agree quite well when compared to the results obtained with different quality of beams and analysis techniques. Investigation on bony tissue is presented for the first time, and a simple model has been carried out in order to segment the mineral and non-mineral components. Finally, a basic set of curves for the linear differential scattering coefficient is proposed in order to simulate photons scattering by tissue in terms of linear combination of such curves.


Nuclear Instruments & Methods in Physics Research Section B-Beam Interactions with Materials and Atoms, 2004

Advanced Monte Carlo For Radiation Physics Particle Transport Simulation and Applications, 2001

Journal of Physics B Atomic Molecular and Optical Physics

Coherent scattering cross sections of 59.54-keV photons on target foils of 64 Gd, 66 Dy, 68 Er, 7... more Coherent scattering cross sections of 59.54-keV photons on target foils of 64 Gd, 66 Dy, 68 Er, 70 Yb, 72 Hf, and 73 Ta at 60°, 90°, and 120°have been measured to provide information on the region of K anomalous elastic scattering. The results are compared with the values calculated by the second perturbative order S matrix and by two procedures based on the form-factor approximation corrected by the anomalous scattering factors. Agreement of the S matrix values is very satisfactory, on the whole, and that of the values given by the form-factor approximations is fairly good.

La recente crisi petrolifera ha in vario modo incrementato l'interesse per la produzione di energ... more La recente crisi petrolifera ha in vario modo incrementato l'interesse per la produzione di energia elettrica tramite fonti alternative. Una possibilità in tale direzione potrebbe essere data dalla reazione nucleare protone-Boro realizzata con l'impiego di macchine tipo Plasma Focus, con le quali e' possibile il raggiungimento di temperature superiori ai 10 9 gradi K, in connessione con l'impiego di tecniche di conversione diretta dell'energia con rendimenti del 60-70%.

X-Ray Spectrometry, 2015

A plasma focus device, devoted to the study of a possible application to the radiotherapy treatme... more A plasma focus device, devoted to the study of a possible application to the radiotherapy treatment of malignant cells, has been recently put into operation. The low-energy (up to 200 keV) X-rays are produced by conversion of the electron beam generated by the device during the pinch phase. The X-ray spectrum has already been fully characterized, and an initial campaign of irradiation of specific cell cultures has been completed. At present, the links between the operational parameters of the actual device, the beam intensity, and the cell irradiation effects are being analyzed, trying to evaluate the advantage of the very high dose rate that can be delivered, of the order of several Gy in a few tens of nanoseconds. Preliminary results on radiobiological effectiveness are presented and discussed.

Lecture Notes in Control and Information Sciences, 1996

ABSTRACT We present a regularization technique for solving inverse ill-posed problems which arise... more ABSTRACT We present a regularization technique for solving inverse ill-posed problems which arise in many fields of applied optics and electrodynamics when one has to deal with restoration of images. Numerical results for electron scattering and free-electron-laser data are shown and the problem of reconstructing a planar image from its line integrals in computerized Compton and X-ray diffraction tomographies is addressed.

2000 IEEE Nuclear Science Symposium. Conference Record (Cat. No.00CH37149), 2000

ABSTRACT The use of a dedicated gamma camera for scintimammography with breast under compression ... more ABSTRACT The use of a dedicated gamma camera for scintimammography with breast under compression can improve the detection of sub centimeter cancers. Unfortunately, detectors based on PSPMT show a poor energy resolution that would not be able to discriminate tumors in the posterior portion of the breast where the scattering of photons, coming from the chest, is particularly prominent. In this paper we introduce the modified truncated SVD (mTSVD) based deconvolution as a numerical approach to enhance the energy resolution. Tc99m calibration spectra were used to numerically describe the detector response function; the degree of ill-posedness of the numerical problem was carefully study in order to perform the deconvolution of ROI, in different breast position, by a unique response function. Eight ROI spectra from breast phantom and two from a patient study were analyzed, respectively. For each or them the energy resolution, after the deconvolution, was about 1.7 times improved. The results shown that the mTSVD based deconvolution can represent an useful tool to increase the energy resolution in scintimammography, and to improve the image quality by further suppression of the Compton scattering

Charged and Neutral Particles Channeling Phenomena - Channeling 2008 - Proceedings of the 51st Workshop of the INFN ELOISATRON Project, 2010

Within the seventh framework programme of the European Union, a threeyear project called Labsync ... more Within the seventh framework programme of the European Union, a threeyear project called Labsync has been recently funded with the aim to design a complete small facility around the MIRRORCLE source, a laboratory sized commercial synchrotron developed in Japan. The medical physics group of Ferrara University is one of the seven partners of the Labsync consortium. Its main task is the design and characterization of the medical beamline. In this contribution a Monte Carlo simulation of the x-ray spectrum obtained by bremsstrahlung interaction of the electron beam with tiny targets are presented. Furthermore, theoretical results of PXR are shown in terms of x-ray flux and beam geometry.

ABSTRACT The authors investigate a technique for the characterisation of biological tissues, base... more ABSTRACT The authors investigate a technique for the characterisation of biological tissues, based on energy analysis of Compton scattered photons. The incident beam consists of 59.54 keV photons and a backscatter geometry is used. Compared to the technique based on the ratio of photons coherently scattered due to the Rayleigh effect and those incoherently scattered due to the Compton effect, the present technique provides similar results for mineral content evaluation, with an error lower than 1%. However it allows the determination of fat content in a soft tissue matrix - even in the cases in which the Rayleigh peaks is not measurable - although the error can rise up to 3%.

IEEE Symposium Conference Record Nuclear Science 2004., 2004

The use of dedicated gamma camera, with high intrinsic spatial resolution can raise the detection... more The use of dedicated gamma camera, with high intrinsic spatial resolution can raise the detection of sub centimeter cancers in Scintimammography. The recent development of new gamma imagers based on scintillation array with high spatial resolution has strongly improved the SNR of the resulting images; however, Compton scattering contamination is the main drawback in Scintimammography, since it limits the sensitivity

Advanced Monte Carlo for Radiation Physics, Particle Transport Simulation and Applications, 2001