A system to monitor the radiation levels is required in the Large Hadron Collider (LHC) and its injection lines in order to quantify the radiation effects on electronics. Thus, the RadMons were ...installed in critical areas where equipment is or will be placed. The first years of operation, successive test campaigns and new requirements, raised the need for a new design of the monitor. The architecture of the new RadMon, the radiation reliability and the design strategy adopted for the sensors, used for monitoring the mixed radiation field of the LHC accelerator, are described highlighting the achieved improvements in terms of radiation robustness and measurement accuracy of a device which is of interest for many other research institutes.
Neutrinos are abundantly produced in the LHC. Flavour composition and energy reach of the neutrino flux from proton-proton collisions depend on the pseudorapidity . At large , energies can exceed the ...TeV, with a sizeable contribution of the τ flavour. A dedicated detector could intercept this intense neutrino flux in the forward direction, and measure the interaction cross section on nucleons in the unexplored energy range from a few hundred GeV to a few TeV. The high energies of neutrinos result in a larger N interaction cross section, and the detector size can be relatively small. Machine backgrounds vary rapidly while moving along and away from the beam line. Four locations were considered as hosts for a neutrino detector: the CMS quadrupole region (25 m from CMS Interaction Point (IP)), UJ53 and UJ57 (90 and 120 m from CMS IP), RR53 and RR57 (240 m from CMS IP), TI18 (480 m from ATLAS IP). The potential sites are studied on the basis of (a) expectations for neutrino interaction rates, flavour composition and energy spectrum, (b) predicted backgrounds and in situ measurements, performed with a nuclear emulsion detector and radiation monitors. TI18 emerges as the most favourable location. Already with 150 fb−1 expected in LHC Run3, a small detector in TI18 could measure, for the first time and with good precision, the high-energy N cross section for all neutrino flavours.
We discuss an experiment to investigate neutrino physics at the LHC, with emphasis on tau flavour. As described in our previous paper Beni et al (2019 J. Phys. G: Nucl. Part. Phys. 46 115008), the ...detector can be installed in the decommissioned TI18 tunnel, ≈480 m downstream the ATLAS cavern, after the first bending dipoles of the LHC arc. The detector intercepts the intense neutrino flux, generated by the LHC beams colliding in IP1, at large pseudorapidity η, where neutrino energies can exceed a TeV. This paper focuses on exploring the neutrino pseudorapity versus energy phase space available in TI18 in order to optimize the detector location and acceptance for neutrinos originating at the pp interaction point, in contrast to neutrinos from pion and kaon decays. The studies are based on the comparison of simulated pp collisions at s= 13 TeV: PYTHIA events of heavy quark (c and b) production, compared to DPMJET minimum bias events (including charm) with produced particles traced through realistic LHC optics with FLUKA. Our studies favour a configuration where the detector is positioned off the beam axis, slightly above the ideal prolongation of the LHC beam from the straight section, covering 7.4 < η < 9.2. In this configuration, the flux at high energies (0.5-1.5 TeV and beyond) is found to be dominated by neutrinos originating directly from IP1, mostly from charm decays, of which ≈50% are electron neutrinos and ≈5% are tau neutrinos. The contribution of pion and kaon decays to the muon neutrino flux is found small at those high energies. With 150 fb−1 of delivered LHC luminosity in Run 3 the experiment can record a few thousand very high energy neutrino charged current (CC) interactions and over 50 tau neutrino CC events. These events provide useful information in view of a high statistics experiment at HL-LHC. The electron and muon neutrino samples can extend the knowledge of the charm PDF to a new region of x, which is dominated by theory uncertainties. The tau neutrino sample can provide first experience on reconstruction of tau neutrino events in a very boosted regime.
The radiation spectra in the CERN Large Hadron Collider (LHC) ranges from gigaelectronvolts down to thermal neutron levels. It is known that the thermal neutrons can significantly affect the ...electronic devices and systems exposed to the radiation environment of the tunnel and the shielded areas of the LHC. CERN's radiation monitoring (RadMon) system uses static random access memories (SRAMs) to measure the contributions to the spectrum from both the high-energy hadrons (>20 MeV) and thermal neutrons. The knowledge of the SRAM thermal neutron cross section is required for evaluating their contribution to the particle spectra and thus identifying the thermal neutron critical area. This paper describes a procedure to acquire, by means of RadMon system, the thermal neutron cross section of SRAM memories in a mixed-field environment. The capabilities of the CERN High AcceleRator Mixed-field facility (CHARM) to measure the thermal neutron sensitivity are then investigated. The procedure is evaluated by comparing the thermal neutron cross sections obtained at CHARM and the one measured using a pure thermal neutron beam. The same procedure could be applied to other devices to understand their susceptibility.
The Radiation MONitoring (RadMON) system is widely employed at CERN to measure the radiation levels in the accelerators, as well as the degradation of electronics located in the Large Hadron Collider ...(LHC) tunnel and shielded areas. Radiation Field Effect Transistors (RadFETs) integrated in the RadMON specifically measure the Total Ionizing Dose (TID) in the accelerators complex and are affected in turn by the CERN radiation field.
The CERN High energy AcceleRator Mixed-field test facility (CHARM) has been built with the intention of reproducing different mixed-fields (atmospheric, space, accelerators, ground,…), to test electronics when exposed to specific radiation environments. Among these fields, LHC-like environments are reproduced to test the RadMON's electronic components: the main goal is a full characterization of the RadMON response and the monitoring of its degradation, when it is exposed to the LHC radiation field.
FLUKA Monte Carlo simulations are crucial at this stage as a powerful tool to reproduce and calibrate the RadMON response. Our present FLUKA Monte Carlo model of the RadFET is well representative of its experimental dose response to the CHARM mixed-field, in unshielded layout. However, the simulations-experiments agreement in lateral shielded positions is less accurate, probably due to the neutron component of the field.
This paper focuses on the study of the RadFET dose response to neutrons, when the dosimeter is irradiated by mixed-fields. FLUKA Monte Carlo simulations and neutron test campaigns performed at ILL (Institut Laue Langevin) and LPSC (Laboratoire de Physique subatomique et de Cosmologie) in Grenoble, as well as at CERN are compared, to further investigate and fully characterize the RadFET response to neutrons.
The simulations-measurements agreement is within the experimental uncertainties, while an overall agreement within a factor 2 is found in positions shielded by the movable walls, at CHARM. The test campaign showed the RadFET is insensitive to the thermal neutron component of the mixed-field at CHARM.
•A two-steps Monte Carlo approach is proposed to simulate the RadFET dose response.•Experimental campaigns were conducted to test the RadFET sensitivity to neutrons.•Measurements were performed using 14 MeV and thermal neutrons beams.•Thermal neutrons at CHARM give a negligible contribution to the total dose.•The overall experiments-simulations agreement is within a factor 2.
In the context of achieving an efficient radiation monitoring system, while also aiming to increase the flexibility of the measurement system, the integrated digital and analog circuitries of the ...floating gate dosimeter (FGDOS) have been upgraded. The capability to control autonomously the recharge process and the easy access to the data allows exploiting the FGDOS in both the autonomous and passive mode. The former provides the cumulated dose measurement by a sensor coupled to a digital interface. The latter implies the reading of the dose only after the irradiation time, performing the dose detection by positioning the sensor without any supply. In this paper, the functionality and characterization of the new features of the FGDOS are demonstrated. The resolution, the dose range, and the error introduced on the measurements are discussed in detail by analyzing the results of irradiation experiments. The use of a filtering technique in different radiation environments is discussed, as well as the capability to retain the information after multiple readings and the power consumption for each configuration.
In this paper, the suitability of floating gate dosimeter as total ionizing dose (TID) detector in mixed fields, representative of large hadron collider (LHC) radiation environment, has been ...investigated. Several experiments were performed in order to characterize the dosimeter. Exposures to γ-ray were carried out to study the sensitivity and linearity of the radiation response. Experiments in mixed radiation field were performed at CERN High energy AcceleRator Mixed field facility (CHARM) at CERN together with RadFETs to compare the performances. In particular, the minimum dose to be cumulated in order to obtain the facility calibration factor has been evaluated and discussed. The effect of the temperature on the output signal has been characterized and a compensation method has been developed and implemented. The fading of the output after irradiation was measured in order to evaluate the retention of the analog information.
The objective of this study was to assess medical students’ knowledge of “medication related osteonecrosis of the jaws” (MRONJ).
A questionnaire survey was administered to all the medical students in ...the last two years of school of medicine at the University of Eastern Piedmont between January 2019 and March 2019. The questionnaire contained a first section regarding demographic and personal data of the student and a second section regarding the knowledge on MRONJ.
On the whole, 72 medical students agreed to participate to this study and filled in the questionnaire. As for indications for the use of bisphosphonates 45 students correctly answered “osteoporosis, osteogenesis imperfecta, multiple myeloma, or metastasis of some malignant tumors”. Almost all students (71 out of 72) answered that a thorough examination of oral cavity and a dentist screening is needed and fundamental before starting bisphosphonate assumption. As for drugs responsible for MRONJ, only 12 students out of 72 correctly answered “bisphosphonates, denosumab, and antiangiogenic drugs”.
A better level of knowledge and awareness by medical doctors and young physicians may lead, in future, to minimize incidence of MRONJ as well as to a better resolution of ONJ cases. Theoretical and practical initiatives could be promoted to improve and consolidate the knowledge of future physicians about this important issue.
The surgical removal of third molars (3 Ms) is often associated with postoperative symptoms such as trismus, edema, and pain. The purpose of this study was to perform a comparative assessment of the ...effect of dexamethasone by different administration routes.
A randomized, prospective study was carried out including patients undergoing the surgical removal of bilateral impacted mandibular 3 Ms. Patients were grouped according to dexamethasone administration routes Group A (intravenous); Group B (intralesional); Group C (oral administration). After surgery, pain, edema, and trismus were recorded. Postoperative symptoms severity (PoSSE) questionnaires were administered too.
108 patients were allocated to group A, 101 to group B, and 106 to group C.
Statistically significant differences (P < .05) with better results were observed as for edema, pain and the results of PoSSe questionnaires by groups A and B.
A single intralesional administration of dexamethasone seems to be effective in decreasing postoperative pain, edema, and symptoms after third molar surgery.
Tuberculous neck lymphadenopathy: A diagnostic challenge Brucoli, M.; Borello, G.; Boffano, P. ...
Journal of stomatology, oral and maxillofacial surgery,
June 2019, 2019-Jun, 2019-06-00, 20190601, Letnik:
120, Številka:
3
Journal Article
Recenzirano
Tuberculosis (TB) continues to be a major health problem for the developing world and a rise in the number of cases has been noted in the western hemisphere too. TB can affect most organs in the head ...and neck region, such as the lymph nodes, larynx, middle ear, oral cavity and pharynx. In particular, as for cervical tuberculosis lymphadenopathy, a predominant involvement of the posterior triangle, supraclavicular, and internal jugular group of nodes bilaterally can be observed. As the early manifestation of Head and Neck TB is often similar to neoplasms, clinical consideration usually occurs only after an ineffective anti-inflammatory treatment, fine-needle aspiration, or biopsy/resection. In fact, this type of presentation often represents a diagnostic and therapeutic challenge to the clinician. Therefore, the aim of the present article is to present and discuss the management of a case of cervical tuberculosis lymphadenopathy.
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