Stefano Latorre - Academia.edu (original) (raw)

Papers by Stefano Latorre

Acta IMEKO

During the second Large Hadron Collider Long Shutdown, the Liquid Argon calorimeter of the ATLAS ... more During the second Large Hadron Collider Long Shutdown, the Liquid Argon calorimeter of the ATLAS experiment at CERN has been upgraded with a new trigger readout electronics which provides digital information with higher granularity to the ATLAS trigger system. In particular, the new LAr Trigger Digitizer Boards will process and digitize the "Super Cells" (group of readout calorimeters cells) and send the processed data to the back-end electronics. The Power Distribution Board is a mezzanine board that provides the power distribution to the LTDB. Before being installed inside the detector these mezzanines must be tested for proper operation, particularly the proper functioning of the voltage regulators that are used to deliver the correct supply voltage. This article will show and discuss the control tests performed on the power distribution boards.

Toward a Science Campus in Milan, 2018

Scintillating optical fibres have shown interesting results for ionizing radiation monitoring. Si... more Scintillating optical fibres have shown interesting results for ionizing radiation monitoring. Since they may enable a remote, punctual and real-time dose assessment, their application in medical dosimetry is very promising. This work aims to summarize some recent progresses in the development and characterization of rareearth doped silica optical fibres. The radioluminescent and dosimetric properties of Ce, Eu and Yb-doped fibres are presented and the advantages and challenges in the use of these sensors for radiation therapy dosimetry are discussed. For such application, an effective approach to deal with the stem effect, i.e. the spurious luminescent signal originated in the light guide as a consequence of its exposition to ionizing radiations (i.e. Cerenkov light and intrinsic fluorescence) must be considered. The stem effect mainly occurs in the UV-VIS region. We demonstrated that the use of a dopant emitting in the near infrared, like Yb, is suitable for an optical discrimination of the dosimetric signal. Indeed, through a characterization of the dosimetric properties of

Astroparticle, Particle, Space Physics and Detectors for Physics Applications, 2014

2014 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2014

ABSTRACT Devices used in future experiments at LHC will be called to work in very hostile environ... more ABSTRACT Devices used in future experiments at LHC will be called to work in very hostile environment. Power supply is a key aspects in this scenario and new converter will be re-designed in order to meet the future requirements. In this paper a main DC-DC power converter, developed by authors in the framework of the APOLLO R&D project, has been proposed and the experimental activity devoted to its characterization is presented and discussed.

2014 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2014

ABSTRACT The reliability of a power converter can be improved using a well-dimensioned cold plate... more ABSTRACT The reliability of a power converter can be improved using a well-dimensioned cold plate. At this aim it is necessary to realize a state of the art cold plate by means of thermal-fluid dynamic numerical analysis and ad-hoc designed experimental test bench. Features and metrological characterization of test bench for cold plate design and verification will be discussed in this paper.

IEEE Transactions on Nuclear Science, 2019

The LHC upgrade is planned to enhance the instantaneous luminosity during Run 3 from 2021 through... more The LHC upgrade is planned to enhance the instantaneous luminosity during Run 3 from 2021 through 2023. The Phase-I upgrade of the trigger readout electronics for the ATLAS Liquid Argon (LAr) Calorimeters will be installed during the second long shutdown of LHC in 2019-2020. In this upgrade, the so-called super cells are introduced to provide higher granularity, higher resolution and longitudinal shower shape information from the LAr calorimeters to the level-1 trigger processors. A new LAr Trigger Digitizer Board (LTDB) will manipulate and digitize 320 channels of super cell signals, and transmit it via 40 fiber optical links to the back end where data are further processed and transmitted to the trigger processors. Five pairs of bidirectional GBT links are used for slow control from the Front-end LInks eXchange (FELIX) in the ATLAS TDAQ system. LTDB also outputs 64 summed analog signals to the current Tower Builder Board via the new baseplane. A test system is developed to test all functions of the LTDB and carry out the performance measurement. A back end PCIe card is designed which has the circuit to interface to the ATLAS trigger, time and control system. It can control the generation of injection signals to the LTDB for performance test. It also configures and calibrate all ASICs on the LTDB.

IEEE Transactions on Applied Superconductivity, 2018

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1989

A charge-sensitive preamplifier showing very low power consumption was developed in two versions:... more A charge-sensitive preamplifier showing very low power consumption was developed in two versions: the first using a JFET SNJ903L has a matching capacitance of 310 pF whereas the second one employing a SNJ3600L has 1100 pF. Both versions have a charge sensitivity of 8 muV/e-. The rise time is lower than 200 ns for both low and high capacitance versions at an input capacitance of 1000 and 3000 pF respectively. The low capacitance version has an equivalent noise charge of 220 e- rms at 0 pF for a CR-(RC)2 shaping at 10 mus shaping time. The noise at 1 mus is 510 e- rms at 0 pF and the noise slope is 1.59 e-/pF. The high capacitance version exhibits 400 e- rms at 0 pF and 10 mus shaping time. At 1 mus the equivalent noise charge is 1100 e- rms and the noise slope is 0.91 e-/pF. The second stage uses operational amplifiers of 16 MHz gain-bandwidth product and is prepared to make a differentiation with pole-zero cancellation if required. The final stage provides a differential output with 50 omega output impedance and can drive a 100 omega twisted pair cable loaded with its characteristic impedance. The total power dissipation is 190 mW for the SNJ903L version whereas the SNJ3600L version dissipates 265 mW. Both versions use +/-6 V. The circuit is mounted using thick film technology onto a 20×50 mm2 ceramic substrate. The project is complemented with the design of a 3000 V, 24 pF/m coaxial cable for detector biasing and signal transport with minimum contribution to the ENC.

Measurement, 2015

Abstract Equipment working in hostile environment are the aim of this paper. Devices operating in... more Abstract Equipment working in hostile environment are the aim of this paper. Devices operating in the hostile environment such as found in future experiments at LHC will be called to work with a level of background radiation able to cause accumulation of a Total Ionizing Dose (TID) up to 10 kGy in Silicon, and fluences up to 2 × 10 13 protons/cm 2 and 8 × 10 13 neutrons/cm 2 but also a high level of magnetic field. This new scenario will be taken into account and it will be very important in future when the High Luminosity (HL) LHC will be operative. It is so important, at this aim, to consider the fact that also the electronic converters devoted to generate the supply for the electronic circuits can be often called to operate in hostile environment. Thus, the power supply is a key aspects in this scenario and new converters need to be ad-hoc re-designed in order to meet the future requirements that will be very stringent. In this paper a main DC–DC power converter, developed by authors in the framework of the APOLLO R&D project, has been proposed. The experimental activity devoted to its electrical and thermal characterization, which can be defined as mandatory in order to obtain an evaluation of the features, is presented and deeply discussed. It is also important to characterize the system in order to evaluate the dependability features such as the RAMS (Reliability, Availability, Maintainability Safety) requirements. In particular, reliability is a very important aspect in experiments as ATLAS at CERN where maintenance should be scheduled only during the shutdown time. Also these aspects have been considered and discussed in the paper.

ACTA IMEKO, 2014

Power supplies for LHC experiments (ATLAS) require DC-DC power converters able to work in very ho... more Power supplies for LHC experiments (ATLAS) require DC-DC power converters able to work in very hostile environments. The APOLLO collaboration, funded by the Italian Istituto Nazionale di Fisica Nucleare (INFN), aims to study dedicated topologies and to design, build and test demonstrators, developing the needed technology for the industrialization phase. Besides the presence of radiation and magnetic fields, thermal specifications are particularly stringent in the working environment. In order to have the wanted features in terms of reliability and availability during the experimental activity, these power electronics circuits must be cooled by specifically designed water heat sinks, and an accurate thermal design is mandatory in order to guarantee safe and reliable operation. Moreover, an optimized thermal design allows to have a maintenance strategy in compliance with the requirements of the experiments. In this paper thermal characterization is used for tuning a coupled thermo-fluid-dynamic 3D numerical model, for both the water heat sink and the whole system. Based on this model an optimized water heat sink was designed and fabricated. Thermal characterization of the power converter demonstrator in different operating conditions shows good agreement with simulation results.

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1995

Systematic measurements of y-rays have been carried out with two Ge diodes on the chromium-51 neu... more Systematic measurements of y-rays have been carried out with two Ge diodes on the chromium-51 neutrino source produced by neutron irradiation to test the GALLEX experiment. The data obtained immediately after irradiation at the reactor and about four months afterwards in the Gran Sasso Laboratory allows a precise neutron activation analysis of the material constituting the source. The values of contaminations leading to radioactive impurities or their upper limits are determined.

IEEE Transactions on Instrumentation and Measurement, 2016

The reliability of a power converter can be improved using a well-dimensioned cold plate. For thi... more The reliability of a power converter can be improved using a well-dimensioned cold plate. For this purpose, it is necessary to realize a state-of-the-art cold plate by means of thermal-fluid dynamic numerical analysis and an ad hoc experimental test bench. Features and metrological characterization of a test bench for cold plate characterization are discussed in this paper. An infrared camera is used to measure the outer surfaces, and thermocouples are employed to measure the temperatures of some inner points, but not all the points of a structure under test are accessible to probes and sensing. An accurate 3-D numerical model has been set to widen the cold plate characterization investigating the values of the variables of interest, such as the temperature and the water velocity field, in all the points of the geometry. A case study is described, showing that using modeling with potentially high accuracy in designing new systems can be useful not only to choose, by comparison, the best solution, saving time and prototyping costs, but also to foresee the system performance.

2015 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2015

The performance in magnetic field (B-field) of a DC-DC converter ad hoc designed for LHC operatio... more The performance in magnetic field (B-field) of a DC-DC converter ad hoc designed for LHC operation has been evaluated. The tests have been carried out at the Laboratorio Acceleratori e Superconduttività Applicata (LASA), in Milan (Italy), in the first months of 2014 and the experimental results are here presented and discussed. The ability to operate in hostile environment of the tested DC-DC converter is very interesting in particular when used in measuring system for physics experiments. In this case, in fact, the presence of radiation and strong magnetic field make electronic devices challenged to function. In particular, in this paper the operation in high B-field environment has been investigated and discussed.

Journal of Instrumentation, 2012

The paper describes power switching converters suitable for possible power supply distribution ne... more The paper describes power switching converters suitable for possible power supply distribution networks for the upgraded detectors at the High Luminosity LHC collider. The proposed topologies have been selected by considering their tolerance to the highly hostile environment where the converters will operate as well as their limited electromagnetic noise emission. The analysis focuses on the description of the power supplies for noble liquid calorimeters, such as the Atlas LAr calorimeters, though several outcomes of this research can be applied to other detectors of the future LHC experiments. Experimental results carried on demonstrators are provided.

Journal of Instrumentation, 2008

The silicon pixel tracking system for the ATLAS experiment at the Large Hadron Collider is descri... more The silicon pixel tracking system for the ATLAS experiment at the Large Hadron Collider is described and the performance requirements are summarized. Detailed descriptions of the pixel detector electronics and the silicon sensors are given. The design, fabrication, assembly and performance of the pixel detector modules are presented. Data obtained from test beams as well as studies using cosmic rays are also discussed.

EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy VIII, 1997

Measurement, 2015

The performance in magnetic field (B-field) of the commercial DC-DC converter LTM8033, from Linea... more The performance in magnetic field (B-field) of the commercial DC-DC converter LTM8033, from Linear Technology, has been evaluated. The tests have been carried out at the Laboratorio Acceleratori e Superconduttività Applicata (LASA), in Milan (Italy), on December 2013 and the experimental results are here presented and discussed. Their ability to operate in hostile environment is particularly interesting for physics experiments where the presence of radiation and strong B field make electronic devices challenged to function. In particular, in this article the operation in high B-field environment will be investigated and discussed.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1992

The lower limits on the neutrinoless and two neutrino betabeta-decay of 136Xe, obtained with a mu... more The lower limits on the neutrinoless and two neutrino betabeta-decay of 136Xe, obtained with a multi-element proportional chamber, are reported. The sensitivity of the experiment was limited by the level of the background contamination. The experimental apparatus, its performance and the background analysis are discussed in detail.

Microelectronics Reliability, 2013

The aim of this work is to show how it is possible to improve the reliability of a power converte... more The aim of this work is to show how it is possible to improve the reliability of a power converter by means of thermal-fluid dynamic numerical analysis. Power electronic converters such as those for High Energy Physics Experiments (HEPEs), must operate in hostile environment with tight thermal constraints and the reliability must be high because of the inaccessibility during the experiments and the high costs of the overall setup. Due to the high power density, the presence of closed environments and the requirement of non-thermal interaction with other subsystems, a liquid cooling system is mandatory. 3D FEM and/or FVM simulations can be used to analyze thermal fluid dynamic behavior of those systems and can be a useful support to design heat sinks optimized for specific applications. We show a comparison of different heat sink solutions to improve the thermal management of a 1.5 kW DC/DC hybrid power module.

Acta IMEKO

During the second Large Hadron Collider Long Shutdown, the Liquid Argon calorimeter of the ATLAS ... more During the second Large Hadron Collider Long Shutdown, the Liquid Argon calorimeter of the ATLAS experiment at CERN has been upgraded with a new trigger readout electronics which provides digital information with higher granularity to the ATLAS trigger system. In particular, the new LAr Trigger Digitizer Boards will process and digitize the "Super Cells" (group of readout calorimeters cells) and send the processed data to the back-end electronics. The Power Distribution Board is a mezzanine board that provides the power distribution to the LTDB. Before being installed inside the detector these mezzanines must be tested for proper operation, particularly the proper functioning of the voltage regulators that are used to deliver the correct supply voltage. This article will show and discuss the control tests performed on the power distribution boards.

Toward a Science Campus in Milan, 2018

Scintillating optical fibres have shown interesting results for ionizing radiation monitoring. Si... more Scintillating optical fibres have shown interesting results for ionizing radiation monitoring. Since they may enable a remote, punctual and real-time dose assessment, their application in medical dosimetry is very promising. This work aims to summarize some recent progresses in the development and characterization of rareearth doped silica optical fibres. The radioluminescent and dosimetric properties of Ce, Eu and Yb-doped fibres are presented and the advantages and challenges in the use of these sensors for radiation therapy dosimetry are discussed. For such application, an effective approach to deal with the stem effect, i.e. the spurious luminescent signal originated in the light guide as a consequence of its exposition to ionizing radiations (i.e. Cerenkov light and intrinsic fluorescence) must be considered. The stem effect mainly occurs in the UV-VIS region. We demonstrated that the use of a dopant emitting in the near infrared, like Yb, is suitable for an optical discrimination of the dosimetric signal. Indeed, through a characterization of the dosimetric properties of

Astroparticle, Particle, Space Physics and Detectors for Physics Applications, 2014

2014 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2014

ABSTRACT Devices used in future experiments at LHC will be called to work in very hostile environ... more ABSTRACT Devices used in future experiments at LHC will be called to work in very hostile environment. Power supply is a key aspects in this scenario and new converter will be re-designed in order to meet the future requirements. In this paper a main DC-DC power converter, developed by authors in the framework of the APOLLO R&D project, has been proposed and the experimental activity devoted to its characterization is presented and discussed.

2014 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2014

ABSTRACT The reliability of a power converter can be improved using a well-dimensioned cold plate... more ABSTRACT The reliability of a power converter can be improved using a well-dimensioned cold plate. At this aim it is necessary to realize a state of the art cold plate by means of thermal-fluid dynamic numerical analysis and ad-hoc designed experimental test bench. Features and metrological characterization of test bench for cold plate design and verification will be discussed in this paper.

IEEE Transactions on Nuclear Science, 2019

The LHC upgrade is planned to enhance the instantaneous luminosity during Run 3 from 2021 through... more The LHC upgrade is planned to enhance the instantaneous luminosity during Run 3 from 2021 through 2023. The Phase-I upgrade of the trigger readout electronics for the ATLAS Liquid Argon (LAr) Calorimeters will be installed during the second long shutdown of LHC in 2019-2020. In this upgrade, the so-called super cells are introduced to provide higher granularity, higher resolution and longitudinal shower shape information from the LAr calorimeters to the level-1 trigger processors. A new LAr Trigger Digitizer Board (LTDB) will manipulate and digitize 320 channels of super cell signals, and transmit it via 40 fiber optical links to the back end where data are further processed and transmitted to the trigger processors. Five pairs of bidirectional GBT links are used for slow control from the Front-end LInks eXchange (FELIX) in the ATLAS TDAQ system. LTDB also outputs 64 summed analog signals to the current Tower Builder Board via the new baseplane. A test system is developed to test all functions of the LTDB and carry out the performance measurement. A back end PCIe card is designed which has the circuit to interface to the ATLAS trigger, time and control system. It can control the generation of injection signals to the LTDB for performance test. It also configures and calibrate all ASICs on the LTDB.

IEEE Transactions on Applied Superconductivity, 2018

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1989

A charge-sensitive preamplifier showing very low power consumption was developed in two versions:... more A charge-sensitive preamplifier showing very low power consumption was developed in two versions: the first using a JFET SNJ903L has a matching capacitance of 310 pF whereas the second one employing a SNJ3600L has 1100 pF. Both versions have a charge sensitivity of 8 muV/e-. The rise time is lower than 200 ns for both low and high capacitance versions at an input capacitance of 1000 and 3000 pF respectively. The low capacitance version has an equivalent noise charge of 220 e- rms at 0 pF for a CR-(RC)2 shaping at 10 mus shaping time. The noise at 1 mus is 510 e- rms at 0 pF and the noise slope is 1.59 e-/pF. The high capacitance version exhibits 400 e- rms at 0 pF and 10 mus shaping time. At 1 mus the equivalent noise charge is 1100 e- rms and the noise slope is 0.91 e-/pF. The second stage uses operational amplifiers of 16 MHz gain-bandwidth product and is prepared to make a differentiation with pole-zero cancellation if required. The final stage provides a differential output with 50 omega output impedance and can drive a 100 omega twisted pair cable loaded with its characteristic impedance. The total power dissipation is 190 mW for the SNJ903L version whereas the SNJ3600L version dissipates 265 mW. Both versions use +/-6 V. The circuit is mounted using thick film technology onto a 20×50 mm2 ceramic substrate. The project is complemented with the design of a 3000 V, 24 pF/m coaxial cable for detector biasing and signal transport with minimum contribution to the ENC.

Measurement, 2015

Abstract Equipment working in hostile environment are the aim of this paper. Devices operating in... more Abstract Equipment working in hostile environment are the aim of this paper. Devices operating in the hostile environment such as found in future experiments at LHC will be called to work with a level of background radiation able to cause accumulation of a Total Ionizing Dose (TID) up to 10 kGy in Silicon, and fluences up to 2 × 10 13 protons/cm 2 and 8 × 10 13 neutrons/cm 2 but also a high level of magnetic field. This new scenario will be taken into account and it will be very important in future when the High Luminosity (HL) LHC will be operative. It is so important, at this aim, to consider the fact that also the electronic converters devoted to generate the supply for the electronic circuits can be often called to operate in hostile environment. Thus, the power supply is a key aspects in this scenario and new converters need to be ad-hoc re-designed in order to meet the future requirements that will be very stringent. In this paper a main DC–DC power converter, developed by authors in the framework of the APOLLO R&D project, has been proposed. The experimental activity devoted to its electrical and thermal characterization, which can be defined as mandatory in order to obtain an evaluation of the features, is presented and deeply discussed. It is also important to characterize the system in order to evaluate the dependability features such as the RAMS (Reliability, Availability, Maintainability Safety) requirements. In particular, reliability is a very important aspect in experiments as ATLAS at CERN where maintenance should be scheduled only during the shutdown time. Also these aspects have been considered and discussed in the paper.

ACTA IMEKO, 2014

Power supplies for LHC experiments (ATLAS) require DC-DC power converters able to work in very ho... more Power supplies for LHC experiments (ATLAS) require DC-DC power converters able to work in very hostile environments. The APOLLO collaboration, funded by the Italian Istituto Nazionale di Fisica Nucleare (INFN), aims to study dedicated topologies and to design, build and test demonstrators, developing the needed technology for the industrialization phase. Besides the presence of radiation and magnetic fields, thermal specifications are particularly stringent in the working environment. In order to have the wanted features in terms of reliability and availability during the experimental activity, these power electronics circuits must be cooled by specifically designed water heat sinks, and an accurate thermal design is mandatory in order to guarantee safe and reliable operation. Moreover, an optimized thermal design allows to have a maintenance strategy in compliance with the requirements of the experiments. In this paper thermal characterization is used for tuning a coupled thermo-fluid-dynamic 3D numerical model, for both the water heat sink and the whole system. Based on this model an optimized water heat sink was designed and fabricated. Thermal characterization of the power converter demonstrator in different operating conditions shows good agreement with simulation results.

Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 1995

Systematic measurements of y-rays have been carried out with two Ge diodes on the chromium-51 neu... more Systematic measurements of y-rays have been carried out with two Ge diodes on the chromium-51 neutrino source produced by neutron irradiation to test the GALLEX experiment. The data obtained immediately after irradiation at the reactor and about four months afterwards in the Gran Sasso Laboratory allows a precise neutron activation analysis of the material constituting the source. The values of contaminations leading to radioactive impurities or their upper limits are determined.

IEEE Transactions on Instrumentation and Measurement, 2016

The reliability of a power converter can be improved using a well-dimensioned cold plate. For thi... more The reliability of a power converter can be improved using a well-dimensioned cold plate. For this purpose, it is necessary to realize a state-of-the-art cold plate by means of thermal-fluid dynamic numerical analysis and an ad hoc experimental test bench. Features and metrological characterization of a test bench for cold plate characterization are discussed in this paper. An infrared camera is used to measure the outer surfaces, and thermocouples are employed to measure the temperatures of some inner points, but not all the points of a structure under test are accessible to probes and sensing. An accurate 3-D numerical model has been set to widen the cold plate characterization investigating the values of the variables of interest, such as the temperature and the water velocity field, in all the points of the geometry. A case study is described, showing that using modeling with potentially high accuracy in designing new systems can be useful not only to choose, by comparison, the best solution, saving time and prototyping costs, but also to foresee the system performance.

2015 IEEE International Instrumentation and Measurement Technology Conference (I2MTC) Proceedings, 2015

The performance in magnetic field (B-field) of a DC-DC converter ad hoc designed for LHC operatio... more The performance in magnetic field (B-field) of a DC-DC converter ad hoc designed for LHC operation has been evaluated. The tests have been carried out at the Laboratorio Acceleratori e Superconduttività Applicata (LASA), in Milan (Italy), in the first months of 2014 and the experimental results are here presented and discussed. The ability to operate in hostile environment of the tested DC-DC converter is very interesting in particular when used in measuring system for physics experiments. In this case, in fact, the presence of radiation and strong magnetic field make electronic devices challenged to function. In particular, in this paper the operation in high B-field environment has been investigated and discussed.

Journal of Instrumentation, 2012

The paper describes power switching converters suitable for possible power supply distribution ne... more The paper describes power switching converters suitable for possible power supply distribution networks for the upgraded detectors at the High Luminosity LHC collider. The proposed topologies have been selected by considering their tolerance to the highly hostile environment where the converters will operate as well as their limited electromagnetic noise emission. The analysis focuses on the description of the power supplies for noble liquid calorimeters, such as the Atlas LAr calorimeters, though several outcomes of this research can be applied to other detectors of the future LHC experiments. Experimental results carried on demonstrators are provided.

Journal of Instrumentation, 2008

The silicon pixel tracking system for the ATLAS experiment at the Large Hadron Collider is descri... more The silicon pixel tracking system for the ATLAS experiment at the Large Hadron Collider is described and the performance requirements are summarized. Detailed descriptions of the pixel detector electronics and the silicon sensors are given. The design, fabrication, assembly and performance of the pixel detector modules are presented. Data obtained from test beams as well as studies using cosmic rays are also discussed.

EUV, X-Ray, and Gamma-Ray Instrumentation for Astronomy VIII, 1997

Measurement, 2015

The performance in magnetic field (B-field) of the commercial DC-DC converter LTM8033, from Linea... more The performance in magnetic field (B-field) of the commercial DC-DC converter LTM8033, from Linear Technology, has been evaluated. The tests have been carried out at the Laboratorio Acceleratori e Superconduttività Applicata (LASA), in Milan (Italy), on December 2013 and the experimental results are here presented and discussed. Their ability to operate in hostile environment is particularly interesting for physics experiments where the presence of radiation and strong B field make electronic devices challenged to function. In particular, in this article the operation in high B-field environment will be investigated and discussed.

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 1992

The lower limits on the neutrinoless and two neutrino betabeta-decay of 136Xe, obtained with a mu... more The lower limits on the neutrinoless and two neutrino betabeta-decay of 136Xe, obtained with a multi-element proportional chamber, are reported. The sensitivity of the experiment was limited by the level of the background contamination. The experimental apparatus, its performance and the background analysis are discussed in detail.

Microelectronics Reliability, 2013

The aim of this work is to show how it is possible to improve the reliability of a power converte... more The aim of this work is to show how it is possible to improve the reliability of a power converter by means of thermal-fluid dynamic numerical analysis. Power electronic converters such as those for High Energy Physics Experiments (HEPEs), must operate in hostile environment with tight thermal constraints and the reliability must be high because of the inaccessibility during the experiments and the high costs of the overall setup. Due to the high power density, the presence of closed environments and the requirement of non-thermal interaction with other subsystems, a liquid cooling system is mandatory. 3D FEM and/or FVM simulations can be used to analyze thermal fluid dynamic behavior of those systems and can be a useful support to design heat sinks optimized for specific applications. We show a comparison of different heat sink solutions to improve the thermal management of a 1.5 kW DC/DC hybrid power module.