Search

The ICARUS collaboration employed the 760-ton T600 detector in a successful 3-year physics run at the underground LNGS laboratory, performing a sensitive search for LSND-like anomalous $\nu _e$ appearance in the CERN Neutrino to Gran Sasso beam, which contributed to the constraints on the allowed neutrino oscillation parameters to a narrow region around 1 eV$^2$. After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. In 2020 the cryogenic commissioning began with detector cool down, liquid argon filling and recirculation. ICARUS then started its operations collecting the first neutrino events from the booster neutrino beam (BNB) and the Neutrinos at the Main Injector (NuMI) beam off-axis, which were used to test the ICARUS event selection, reconstruction and analysis algorithms. ICARUS successfully completed its commissioning phase in June 2022. The first goal of the ICARUS data taking will be a study to either confirm or refute the claim by Neutrino-4 short-baseline reactor experiment. ICARUS will also perform measurement of neutrino cross sections with the NuMI beam and several Beyond Standard Model searches. After the first year of operations, ICARUS will search for evidence of sterile neutrinos jointly with the Short-Baseline Near Detector, within the Short-Baseline Neutrino program. In this paper, the main activities carried out during the overhauling and installation phases are highlighted. Preliminary technical results from the ICARUS commissioning data with the BNB and NuMI beams are presented both in terms of performance of all ICARUS subsystems and of capability to select and reconstruct neutrino events. The ICARUS collaboration employed the 760-ton T600 detector in a successful three-year physics run at the underground LNGS laboratory studying neutrino oscillations with the CERN Neutrino to Gran Sasso beam (CNGS) and searching for atmospheric neutrino interactions. ICARUS performed a sensitive search for LSND-like anomalous $\nu_e$ appearance in the CNGS beam, which contributed to the constraints on the allowed parameters to a narrow region around 1 eV$^2$, where all the experimental results can be coherently accommodated at 90% C.L.. After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. In 2020, cryogenic commissioning began with detector cool down, liquid argon filling and recirculation. ICARUS has started operations and successfully completed its commissioning phase, collecting the first neutrino events from the Booster Neutrino Beam (BNB) and the Neutrinos at the Main Injector (NuMI) beam off-axis, which were used to test the ICARUS event selection, reconstruction and analysis algorithms. The first goal of the ICARUS data taking will then be a study to either confirm or refute the claim by Neutrino-4 short baseline reactor experiment both in the $\nu_\mu$ channel with the BNB and in the $\nu_e$ with NuMI. ICARUS will also address other fundamental studies such as neutrino cross sections with the NuMI beam and a number of Beyond Standard Model searches. After the first year of operations, ICARUS will commence its search for evidence of a sterile neutrino jointly with the Short Baseline Near Detector, within the Short-Baseline Neutrino program.

The ICARUS T600 liquid argon (LAr) time projection chamber (TPC) underwent a major overhaul at CERN in 2016–2017 to prepare for the operation at FNAL in the Short Baseline Neutrino (SBN) program. This included a major upgrade of the photo-multiplier system and of the TPC wire read-out electronics. The full TPC wire read-out electronics together with the new wire biasing and interconnection scheme are described. The design of a new signal feed-through flange is also a fundamental piece of this overhaul whose major feature is the integration of all electronics components onto the signal flange. Initial functionality tests of the full TPC electronics chain installed in the T600 detector at FNAL are also described. The ICARUS T600 liquid argon (LAr) time projection chamber (TPC) underwent a major overhaul at CERN in 2016-2017 to prepare for the operation at FNAL in the Short Baseline Neutrino (SBN) program. This included a major upgrade of the photo-multiplier system and of the TPC wire read-out electronics. The full TPC wire read-out electronics together with the new wire biasing and interconnection scheme are described. The design of a new signal feed-through flange is also a fundamental piece of this overhaul whose major feature is the integration of all electronics components onto the signal flange. Initial functionality tests of the full TPC electronics chain installed in the T600 detector at FNAL are also described.

ICARUS T600 will be operated as far detector of the Short Baseline Neutrino program at Fermilab (U.S.A.), which foresees three liquid argon time projection chambers along the Booster Neutrino Beam line to search for a LSND-like sterile neutrino signal. The detector employs 360 photomultiplier tubes, Hamamatsu model R5912-MOD, suitable for cryogenic applications. A total of 400 PMTs were procured from Hamamatsu and tested at room temperature to evaluate the performance of the devices and their compliance to detect the liquid argon scintillation light in the T600 detector. Furthermore 60 units were also characterized at cryogenic temperature, in liquid argon bath, to evaluate any parameter variation which could affect the scintillation light detection. All the tested PMTs were found to comply with the requirements of ICARUS T600 and a subset of 360 specimens was selected for the final installation in the detector. ICARUS T600 will be operated as far detector of the Short Baseline Neutrino program at Fermilab (USA), which foresees three liquid argon time projection chambers along the Booster Neutrino Beam line to search for a LSND-like sterile neutrino signal. The detector employs 360 photomultiplier tubes, Hamamatsu model R5912-MOD, suitable for cryogenic applications. A total of 400 PMTs were procured from Hamamatsu and tested at room temperature to evaluate the performance of the devices and their compliance to detect the liquid argon scintillation light in the T600 detector. Furthermore 60 units were also characterized at cryogenic temperature, in liquid argon bath, to evaluate any parameter variation which could affect the scintillation light detection. All the tested PMTs were found to comply with the requirements of ICARUS T600 and a subset of 360 specimens was selected for the final installation in the detector.

The ICARUS T600, a liquid argon time projection chamber (LAr-TPC) detector mainly devoted to neutrino physics, underwent a major overhauling at CERN in 2016–2017, which included also a new design of the read-out electronics, in view of its operation in Fermilab on the Short Baseline Neutrino (SBN) beam from 2019. The new more compact electronics showed capability of handling more efficiently the signals also in the intermediate Induction-2 wire plane with a significant increase of signal to noise (S/N), allowing for charge measurement also in this view. The new front-end and the analog to digital conversion (ADC) system are presented together with the results of the tests on 50 liters liquid argon TPC performed at CERN with cosmic rays. The ICARUS T600, a liquid argon time projection chamber (LAr-TPC) detector mainly devoted to neutrino physics, underwent a major overhauling at CERN in 2016-2017, which included also a new design of the read-out electronics, in view of its operation in Fermilab on the Short Baseline Neutrino (SBN) beam from 2019. The new more compact electronics showed capability of handling more efficiently the signals also in the intermediate Induction 2 wire plane with a significant increase of signal to noise (S/N), allowing for charge measurement also in this view. The new front-end and the analog to digital conversion (ADC) system are presented together with the results of the tests on 50 liters liquid argon TPC performed at CERN with cosmic rays.

We have analysed group therapy efficacy in weight loss of obese outpatients, non responders to previous hypocaloric treatments. The results we have obtained during the last 8 years have been compared to those reported in literature, to our previous observations and to results obtained in a group of obese outpatients in traditional diet-therapy. The mean weight loss in patients followed for 6 months with group therapy was 5.5% of the initial weight (IW); 48.5% of them lost more than 5% and 13% lost more than 10% of IW. The results obtained in a traditional treated group were a little better: mean weight loss was −6.6%, 61% lost more than 5% and 22% more than 10% of IW. So, in our opinion, group therapy can be usefully applied only in selected patients (i.e. older in age/non-responders to traditional treatments), where it might have a possible role as a more cost-effective treatment.

As part of the development program for the ICARUS experiment, which consists of a very large time projection chamber (TPC) filled with ultra-pure liquid Ar (LAr), we have carried out tests with different purifier systems, in order to evaluate the performance of the various parts and to improve the purification techniques developed so far. Electron lifetime τ in LAr has been determined with an improved method based on the measurement of the attenuation of a current due to an electron cloud, photoproduced by a laser pulse impinging on a metallic cathode and moving in a small drift chamber filled with the purified LAr. Results of the above-mentioned tests are reported. During these tests, we observed repeatedly and reproducibly an increase of τ that took place over a period of 10 to 20 h after liquefaction. Several tests performed in an attempt to elucidate this effect, suggest that the increase in τ is due to adsorption of electron-attaching impurities on the walls of the stainless steel container, a process governed by thermal diffusion. The electron lifetime monitoring system reported here was used to measure the electric field dependence of τ in purified LAr doped with O2 and CO2, for fields 100 V/cm < E < 800 V/cm: The results for O2 are consistent with published data.

Contrast methods are based on evaluation of the "distance" between the values of a representative parameter of the phenomenon affecting the zones to be classified. The selection of a particular value of the reference by means of an operator is based on the fact that the operator has an a priori knowledge about the specimen. The Class Contrast method presented in this paper overcomes these limitations and works on the basis of 2 guidelines: 1) contrast methods are differential methods, therefore final result should not depend on the arbitrary selection of the reference points; 2) classes are represented by a certain number of points, all affected by the same noise, and all these points should contribute to increase the final SNR. Class Contrast has been successfully applied to thermal NDT on composites. Results are reported together with comparison with results from application of classical thermal contrast method.

The technique described in this paper is for one-side thermal diffusivity measurement. A single stripe-shaped pulse provided by a flash lamp is used to heat the front surface of a specimen slab. Classical methods for estimating a parameter out of a distribution involve fitting the temperature distribution with its theoretical model. With the technique described in this paper the evolution of the temperature distribution along a line perpendicular to the heated stripe is analyzed in the frequency domain. An estimate of the thermal diffusivity is then obtained from comparison of the phase component behavior with an abacus similarly built from the theoretical model. This technique is valid for any shape of flash lamp pulse (i.e. laser spot), and can be used also for estimating the thermal diffusivity of anisotropic materials. The choice of the stripe shape is due to the limitations of the simulation environment used.© (2000) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

The technique described in this paper is for one-side thermal diffusivity measurement. A single stripe-shaped pulse provided by a flash lamp is used to heat the front surface of a specimen slab. Classical methods for estimating a parameter out of a distribution involve fitting the temperature distribution with its theoretical model [1][2]. With the technique described in this paper the evolution of the temperature distribution along a line perpendicular to the heated stripe is analyzed in the frequency domain. An estimate of the thermal diffusivity is then obtained from comparison of the phase component behavior with an abacus similarly built from the theoretical model.

Pulse Phase Thermography (PPT) has been reported as a novel powerful technique of the thermal NDE. It employs application of the Discrete Fourier Transform (DFT) to thermal images obtained following flash heating of the front surface of a specimen. The computed phasegrams are excellent for defect visualization in a wide range of materials. This is in part due to their low sensitivity to uneven heating. This work is an attempt to analyze advantages and limitations of PPT. Results of application of the DFT to simulated temperature decays are presented. The temperature evolution on a surface has been simulated based on an analytical solution of the one-dimensional heat diffusion problem. A more sophisticated study has been done for different sizes of defects using numerical solution of the three-dimensional mathematical model. Capabilities of PPT for in-depth scanning and for monitoring of the material loss are discussed. The recommendations for the practical application of the PPT are presented. Experimental results obtained following these recommendations are reported.

Pulse Phase Thermography (PPT) has been reported as a novel powerful technique of the thermal NDE. It employs application of the Discrete Fourier Transform (DFT) to thermal images obtained following flash heating of the front surface of a specimen. The computed phasegrams are excellent for defect visualization in a wide range of materials. This is in part due to their low sensitivity to uneven heating. This work is an attempt to analyze advantages and limitations of PPT. Results of application of the DFT to simulated temperature decays are presented. The temperature evolution on a surface has been simulated based on an analytical solution of the one-dimensional heat diffusion problem. A more sophisticated study has been done for different sizes of defects using numerical solution of the three-dimensional mathematical model. Capabilities of PPT for in-depth scanning and for monitoring of the material loss are discussed. The recommendations for the practical application of the PPT are presented. Experimental results obtained following these recommendations are reported.

Not always during in-field measurements it is possible to reproduce laboratory conditions. This is especially true in thermography-based techniques which are most likely to be affected by unwanted external heat fluxes. Typical examples of parasitic heat sources may be spatial heater unevenness, reflections, heater power variations in time, real external heat flux sources, specimen curvature variation, misplacement of heater effects, etc. These heat sources contribute to reduce the overall SNR. As a consequence, a technique perfectly working in laboratory, when ported to field environment may not yield the expected results. Moreover the repeatability of the measurement is not ensured due to the randomness of these sources. D2D is a transient thermography technique based on moving a linear heater over a specimen's surface and recording the thermal evolution of the hated surface by means of a thermal imager.

Various Thermal/Infrared Non Destructive Testing techniques are gaining interest expanding the number of applications. The non-contact nature and the increased reliability of findings make this method particularly interesting for the works of art NDE. This work is devoted to the frescoes inspection for the sizing of detached plaster areas. Air filled voids in between the coloured plaster and the supporting wall are well identified due to the increased thermal resistance. Defects are evaluated from the evolution in time of the surface temperature detected by an IR camera in transient thermal regime. The inspection of large surfaces was recently and successfully applied by means of a lateral heating [1–2]. An advantage of this procedure is the reduced inspection time. This aspect is extremely important when the thermal diffusivity of the material is low, so that a long time is needed for the thermal signal appearance.

A sensitive aspect of thermal techniques is represented by the very nature of the involved (thermal) stimulus. It is very easy in effect to encounter parasitic (unwanted) heat sources in a thermal measurement [1], which at the end contribute to worsten the signal to noise ratio. This means that applying thermal techniques in field environment is far more difficult than in environments where heat sources are well under control (typical laboratory environment). Special techniques have to be used in such situations to eliminate the parasitic sources effects in order to ensure the repeatability of the measurement, that is the capability of the technique to yield the same results from the same specimen in different working conditions, or in other words making the technique practically usable.

Not always during in-field measurements it is possible to reproduce laboratory conditions. This is especially true in thermography-based techniques which are most likely to be affected by unwanted external heat fluxes. Typical examples of parasitic heat sources (real or equivalent) may be spatial heater unevennesses, reflections, heater power variations in time, real external heat flux sources(sun, lamps, radiators, human beings, etc.), specimen curvature variation, misplacement of heater effects, etc. These heat sources contribute to reduce the overall SNR. As a consequence, a technique perfectly working in laboratory, when ported to field environment may not yield the expected results. Moreover the repeatability of the measurement is not ensured due to the randomness of these sources. D2D (Defect To Direction) is a transient thermography technique based on moving a linear heater (I-D) over a specimen's surface and recording the thermal evolution of the heated surface by means of a thermal imager. It's main specifications are: Insensitivity to some of the parasitic heat sources Decision-free operation (no skilled personnel required) Real time capability Large surface exploration capability Very low false call/missed defect probability. Tests on CFRP plates have been carried out. Results are reported.