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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.

This work describes in detail the Radiation Hardness Assurance methodology applied to the development of new radiation tolerant power converter control system for the Large Hadron Collider at the European Organization for Nuclear Research (CERN). This system is based primarily on commercial-off-the-shelf components for which the extensive testing scheme is applied to decrease the probability of radiation failures during the operation of the LHC machine in the high-luminosity operating conditions era.

We use a single event latchup (SEL) model calibrated to heavy ion (HI) and proton data below 230 MeV to extrapolate the proton cross section to larger energies and evaluate the impact of the potential cross section increase with energy on the SEL rate in different environments. We show that in the case of devices with a large LET onset for HI and a certain amount of tungsten near the sensitive volume (SV), the calculated failure rates for energetic environments based on monoenergetic test data can significantly underestimate the real value. In addition, we show through measurements using a 480 MeV beam and an inspection of the device's architecture that the model was successful in estimating the SEL cross section and tungsten volume per cell.

Ionizing radiations affect installed electronics, limit equipment lifetimes and eventually alter materials both in space applications as well as high energy accelerators and physics experiments. In order to monitor radiation levels and predict equipment and material lifetimes, an accurate radiation dosimetry is highly important and very challenging often due to two main reasons: (i) large areas and (ii) extended dose range of interest.

International audience; In this paper, we report on the development and first deployment of a distributed optical fiber radiation sensor (DOFRS) for the online monitoring of radiation levels in the high-energy accelerator facilities of CERN. The DOFRS is composed of two basic parts: a set of suitably chosen radiation sensitive optical fibers (OFs), to be installed in the machine tunnel, and an optical time domain reflectometer (OTDR), to be installed in a radiation-free area. We carried out a calibration of the radiation response of a P-doped multimode OF under $^{60}$Co $\gamma$-rays and in the mixed-field radiation environment of the CHARM facility at CERN. By performing OTDR measurements, we are able to probe the radiation-induced attenuation in the OF along its length and calculate the deposited radiation dose with a spatial resolution of 1 m. In this paper, we describe the main features associated with DOFRS implementation in the proton synchrotron booster (PSB) at CERN. We also report the first results obtained from the monitoring of PSB radiation levels since its recommissioning in April 2017. The performances and advantages of the DOFRS system are discussed.

The floating gate dosimeter is a new dosimeter whose performance can be improved by applying different techniques at sensor design and at readout level. This work is focused on the active sensor part and it extrapolates the key parameters influencing the sensitivity and the noise of the floating gate by means of real measurements and models. The measurements have been carried out on different type of structures and compared with two theoretical models presented in the literature.

The need to qualify systems for high radiation levels for accelerator or space environment has led to the development of a new approach based on reliability concepts. Conventional qualification approaches provide conservative radiation designs without the ability to estimate the system survival reliabilities beyond the required radiation hardness. In this work, an approach is described to estimate system survival reliabilities against radiation-induced failures based on component radiation response. For this purpose, models and methods are proposed to estimate the single component survival reliability against the different kinds of radiation-induced failures. A feasibility study of the use of such an approach for qualification purpose is presented with a demonstration of survival reliability estimation of a case-study system.

The qualification process of CubeSat systems under radiation is long and requires tests at several facilities. An alternative qualification methodology is being studied at the CHARM facility with the CELESTA radiation module demonstrator.

Before using a complex device in space, one shall evaluate its behavior in a radiative environment. We present here the work performed to estimate the Single Event Effect response of a Zynq® processor for the Eye-Sat nanosatellite.

CERN provides unique irradiation facilities for applications in many scientific fields. This paper summarizes the facilities currently operating for proton, gamma, mixed-field and electron irradiations, including their main usage, characteristics and information about their operation. The new CERN irradiation facilities database is also presented. This includes not only CERN facilities but also irradiation facilities available worldwide.

The Super Proton Synchrotron (SPS) will serve as an injector to the Large Hadron Collider (LHC) at CERN as well as it is used to accelerate and extract proton beams for fixed target experiments. In either case, safety of operation is a very important issue that needs to be carefully addressed. This paper presents detailed numerical simulations of the thermodynamic and hydrodynamic response of solid targets made of copper and tungsten that experience impact of a full SPS beam comprized of 288 bunches of 450 GeV/c protons. These simulations have shown that the material will be seriously damaged if such an accident happens. An interesting outcome of this work is that the SPS can be used to carry out dedicated experiments to study High Energy Density (HED) states in matter.

In the context of the CERN 'Radiation To Electronics (R2E)' project, the vulnerability of a variety of components for particle accelerators electronics to single event effects, total ionizing dose and displacement damage has been analysed. The tested parts include analog, linear, digital, and hybrid devices and a summary of radiation test results is provided in this paper.

CERN provides unique irradiation facilities for applications in dosimetry, metrology, intercomparison of radiation protection devices, benchmark of Monte Carlo codes and radiation damage studies to electronics.

The radiation environment encountered at high-energy hadron accelerators strongly differs from the environment relevant for space applications. The mixed-field expected at modern accelerators is composed of charged and neutral hadrons (protons, pions, kaons and neutrons), photons, electrons, positrons and muons, ranging from very low (thermal) energies up to the TeV range. This complex field, which is extensively simulated by Monte Carlo codes (e.g. FLUKA) is due to beam losses in the experimental areas, distributed along the machine (e.g. collimation points) and deriving from the interaction with the residual gas inside the beam pipe. The resulting intensity, energy distribution and proportion of the different particles largely depends on the distance and angle with respect to the interaction point as well as the amount of installed shielding material. Electronics operating in the vicinity of the accelerator will therefore be subject to both cumulative damage from radiation (total ionizing dose, displacement damage) as well as single event effects which can seriously compromise the operation of the machine. This, combined with the extensive use of commercial-off-the-shelf components due to budget, performance and availability reasons, results in the need to carefully characterize the response of the devices and systems to representative radiation conditions.

International audience; —This paper presents Monte-Carlo simulations based on the Fluka code aiming to calculate the contribution of the neutron albedo at a given date and altitude above the Earth chosen by the user. Results consist of a two-parameter distribution, the neutron energy and the angle to the tangent plane of the sphere containing the orbit of interest, and are provided by geographical position above the Earth at the chosen altitude. In this paper, a major improvement was introduced with respect to the previous model concerning the filtering of incoming cosmic rays hitting the upper atmosphere. This more accurate estimation of neutron albedo is of prime importance for the radiation belts modelers because it constitutes the main source of protons > 40 MeV of the inner radiation belt.

Dosimeters based on floating gate structure exhibit a linear radiation response, whose sensitivity is required to be highly stable in order to achieve an accurate dose measurement. The understanding of the mechanisms behind the sensitivity degradation is, therefore, a fundamental task in order to improve the design of these devices. In this work, the causes of the loss of sensitivity are analyzed. The role of the injection rate and the reading MOS on are discussed in detail, by analyzing the results of radiation experiments specifically performed. The study sheds light on the importance of the choice of the amplitude of the linear range and the indirect effect of high dose rates. In addition, the TID lifetime of the core floating gate sensor is pointed out.

We apply a Monte Carlo based integral rectangular parallel-piped (IRRP) approach to evaluate the impact of heavy ion reaction products on the Galactic Cosmic Ray (GCR) Single Event Effect (SEE) rate, concluding that owing to their similar high-energy (> 100 MeV/n) SEE cross section and much larger abundance, protons are expected to be the dominating contributor. In addition, a broad set of components, ions and energies is used to explore the sub-LET threshold experimental region for standard ground-level heavy ion test energies, identifying an overall decreasing trend in the 10-80 MeV/n range due to the decreased contribution of complete and break-up fusion, and pointing out the limitations associated to the application of Monte Carlo SEE models in this energy interval.

As part of its post-LHC high energy physics program, CERN is conducting a study for a new proton-proton collider, called Future Circular Collider (FCC-hh), running at center-of-mass energies of up to 100 TeV in a new 100 km tunnel. The study includes a 90-350 GeV lepton collider (FCC-ee) as well as a lepton-hadron option (FCC-he). In this work, FLUKA Monte Carlo simulation was extensively used to perform a first evaluation of the radiation environment in critical areas for electronics in the FCC-hh tunnel. The model of the tunnel was created based on the original civil engineering studies already performed and further integrated in the existing FLUKA models of the beam line. The radiation levels in critical areas, such as the racks for electronics and cables, power converters, service areas, local tunnel extensions was evaluated.

International audience; A single event latchup (SEL) experiment based on commercial static random access memory (SRAM) memories has recently been proposed in the framework of the European Organization for Nuclear Research (CERN) Latchup Experiment and Student Satellite nanosatellite low Earth orbit (LEO) space mission. SEL characterization of three commercial SRAM memories has been carried out at the Paul Scherrer Institut (PSI) facility, using monoenergetic focused proton beams and different acquisition setups. The best target candidate was selected and a circuit for SEL detection has been proposed and tested at CERN, in the CERN High Energy AcceleRator Mixed-field facility (CHARM). Experimental results were carried out at test locations representative of the LEO environment, thus providing a full characterization of the SRAM cross sections, together with the analysis of the single-event effect and total ionizing dose of the latchup detection circuit in relation to the particle spectra expected during mission. The setups used for SEL monitoring are described, and details of the proposed circuit components and topology are presented. Experimental results obtained both at PSI and at CHARM facilities are discussed.

International audience; In paper we present the results from distributed optical fiber radiation sensing measurements at the “Cern High energy AcceleRator Mixed field facility”, CHARM. The measurements have been carried out on a multimode (MM) radiation sensitive P-doped optical fiber. The distributed measurements have then been carried out by means of an Optical Time Domain Reflectometry (OTDR) system using different interrogation and acquisition parameters to understand their influence on the results. We demonstrate the possible localization of the total dose with meter scale spatial resolutions and dose resolution down to 10-15 Gy. The obtained distributed dose profiles are validated by the benchmark with RadFET dosimeters and appear very promising for high energy accelerators and physics experiments as well as for industrial applications.

H4IRRAD is a new mixed-field irradiation area at CERN, designed for testing LHC electronic equipment, especially large volume assemblies such as full electronics racks of high current power converters. The area uses alternatively an attenuated primary 400 GeV/c proton beam slowly extracted from the CERN SPS, or a secondary, mainly proton, beam of 280 GeV/c directed towards a 1 m long, 7.5 cm diameter Cu target. Different shielding layers are used to reproduce a radiation field similar to the LHC “tunnel” and “shielded” areas in test zones around the target. The FLUKA Monte Carlo code was used for the design and optimization studies with the objective to match, as closely as possible, the mixed-radiation fields in the LHC ring, whilst also maintaining the lowest possible field gradient within the irradiation areas. Activation studies for the target, equipment, and the air volume were performed in order to assess safety risks, specify the access conditions and determine how to handle the equipment after irradiation. The test area has been in operation since 2011 with numerous tests performed already. The design concept of H4IRRAD, along with comparison studies between the FLUKA predictions and the measurements for the mixed radiation field characterization will be presented in this paper.

Samples of copper, aluminium and stainless steel with well-characterized elemental compositions were irradiated in the stray radiation field created by a 2.5 GeV electron beam hitting a copper dump. After the irradiation the induced activity in the samples was analysed with gamma-ray spectrometry. The beam intensity monitoring with a current transformer was verified in an additional study by irradiating gold-foils stacked in between copper blocks and by analysing the production of Au for which detailed experimental cross section data exist. All results were finally compared to the predictions obtained with the FLUKA Monte-Carlo code. Excellent agreement between measurement and simulation within a few percent was obtained for the gold-foils irradiation confirming the accuracy of the beam monitoring. The benchmark of the FLUKA results with the data of the material samples showed good agreement, for many nuclides within 30%.

The Physics Beyond Colliders study investigates the feasibility of future projects and experiments using CERN facilities. In the scope of this study, a future operation of the NA62 experiment using the existing K12 beam line operated in beam dump mode is discussed. Such a setup allows for a search for dark sector particles, e.g. heavy neutral leptons, dark photons and axions. Production of these hypothetical particles requires the 400GeV/c proton beam extracted from the Super Proton Synchrotron (SPS) to be dumped on a massive dump collimator located in the first part of the K12 beam line. The decay of these dark sector particles, for example, into muons could be detected by the NA62 experimental setup. However, muons created in particle interactions with material and from in-flight decays of secondary hadrons pose a critical background for this kind of experiment. Magnetic sweeping serves as an efficient tool for reducing this background. This paper discusses the simulation studies conducted with the software framework G4beamline to reduce the expected single-muon rate for this experiment. The required beam line modifications, in particular the removal of the beryllium target and repositioning of the dump, have been implemented into this model. A comparison of simulated muon distributions and spectra available experimental data, already taken in test runs, has been made in order to validate the beam line simulation. Finally, additional beam line modifications to further suppress the muon background are elaborated upon. These studies show a potential further reduction of a factor four of the total single-muon rate relative to the nominal setup over the full momentum range, and up to a factor twenty considering only muons with momenta [Formula: see text].

International audience; This work focuses on the effects of high dose ionizing radiation, up to 10 MGy(SiO2), on P‐doped multimode optical fibers (OF) at different irradiation temperatures. The investigation is based on two complementary experimental techniques: radiation‐induced attenuation (RIA) measurements and electron paramagnetic resonance (EPR). The latter technique allows measuring the P1, P2, metastable‐POHC and stable‐POHC defects. Three OF samples are drawn from the same preform to evaluate the influence of changing their drawing conditions of the OFs on the radiation responses. This first study is performed under X‐rays at room temperature. The results are compared with the ones of γ‐rays irradiation. The latter allows to highlight a linear correlation between the NIR absorption band at 1.6 µm and the EPR signal of P1 defects, which supports D. Griscom's assignment of this absorption band to the P1 defect. The combined effect of ionizing radiation and irradiation temperature is also investigated extensively: online RIA measurements as well as post‐mortem EPR measurements for irradiation temperatures ranging from 25 to 280 °C and doses up to 3 MGy are performed. Both RIA and EPR data show that increasing the irradiation temperature can lead to an increased production of point defects and associated absorption bands. This result is of great importance for the employment of P‐doped OFs in radiation environment.

To compare body composition and abdominal fat partitioning between 5- to 7-year old children born preterm and born at term. We hypothesized children born preterm to have a higher body fat percentage and higher percentage of intra-abdominal adipose tissue (%IAAT) compared with their peers born at term.A total of 236 children aged 5-7 years, ie, 116 children born preterm (gestational age 29.8 ± 2.6 [30; 24-33] weeks [mean ± SD {median; range}]) and 120 children born at term were included. Body composition was measured by bioelectrical impedance analysis and %IAAT by magnetic resonance imaging. Body mass index, skin fold thickness, and waist-to-hip ratio were investigated as further measures of body composition. Dietary records were compared between both groups.Children born preterm were shorter (120 cm vs 123 cm, P.001), lighter (21.8 kg vs 24.3 kg, P.001), and had a lower body mass index (15.1 kg/m(2) vs 15.9 kg/m(2), P = .003) compared with controls. There were no differences in %IAAT (n = 154), and body fat mass although energy uptake was higher in preterms (335 kJ/kg/d vs 302 kJ/kg/d, P = .03).At the age of 5-7 years, children born preterm showed neither increased fat mass nor intra-abdominal adiposity.

More than 400 radiation monitoring devices are nowadays installed in the CERN LHC tunnel and its adjacent shielded areas to measure radiation effects on the electronics and anticipate possible device degradation. Supported by the experience accumulated in the last years' operation, a major system upgrade has been prepared. In this paper, the operational architecture of the new detector will be discussed focusing mainly on the advantages provided to the accelerator radiation monitoring impacting electronics installed in its vicinity. The new data acquisition software infrastructure will be detailed referring to the implemented approach to make the management and the maintenance of the entire system easier.

International audience; The continuous need for upgrading the instrumentation and control electronics operating in various CERN experiments and along the LHC accelerator, has driven the qualification process of the new Flash-Based SmartFusion2 FPGAs; a leading candidate to be embedded in future systems. The radiation testing conditions have been chosen to fit the unique CERN environment, while the setup is carefully chosen to qualify all the subcomponents of the SoC FPGA that the engineering teams of CERN are considering for exploitation.

The radiation environment produced by the CERN accelerator complex includes different kinds of particles whose energy can vary in a wide spectrum. In this framework, the radiation monitoring is a challenging task that needs to be continuously improved. For this aim, a comprehensive study and characterization of Floating Gate Dosimeter is presented in this work. Radiation responses to gamma rays at different dose rates have been analyzed. The linearity of the sensors and the sensitivity dependency on the temperature variation has been evaluated by performing specific tests. The output fading phenomenon has been investigated.

We present experimental evidence of electron induced upsets in a reference ESA SEU monitor, the SEU based particle detector, induced by 200 MeV electron beam at the VESPER facility at CERN. Comparison of experimental cross sections and simulated cross sections are shown and the differences are analyzed. Possible secondary contributions to the upset rate by neutrons and cumulative dose effects are discussed, showing that electronuclear reactions are the expected SEU mechanism. Insight is given as to possible overall electron contribution to the upset rates in the Jovian radiation environment inside a typical spacecraft shielding are evaluated.

SEL characterization of commercial SRAM memories has been carried out to select the best candidate for a latchup experiment in LEO space environment. A circuit for SEL detection and protection has been proposed and tested at CERN in the CHARM mixed-field facility.

SRAM memories are widely used as particle fluence detectors in high radiation environments, such as in the Radiation Monitoring System (RadMon) currently in operation in the CERN accelerator complex. Multiple Cell Upsets (MCUs), arising from micro-latchup events, are characterized by a large number of SEUs, ultimately affecting the measurement of particle fluxes and resulting in corrupted data and accuracy losses. A study of the generation of this type of SEU bursts was performed on an 8 Mbit 90-nm SRAM memory. Experimental tests were carried out with a focused beam of protons on target as well as in a mixed field environment dominated by high energy hadrons. A solution approach using an on-line detection and correction algorithm embedded on an FPGA was investigated and evaluated for use on a RadMon device.

Background/Aims: Theoretically, the trait-model parameters (disease allele frequency and penetrance function) can be estimated without bias in a MOD score linkage analysis. We aimed to practically evaluate the MOD score approach regarding its ability to provide unbiased trait-model parameters for various pedigree-type and trait-model scenarios. We further investigated the ability of the MOD score approach to detect imprinting using affected sib pairs (ASPs) and affected half-sib pairs (AHSPs) when all parental genotypes are missing. Methods: Simulated pedigree data were analyzed using the GENEHUNTER-MODSCORE software package. Parameter estimation performance in terms of bias and variability was evaluated with regard to trait-model type and pedigree complexity. Results: Generally, parameters were estimated with lower bias and variability with increasing pedigree complexity, especially for recessive and overdominant models. However, dominant and additive models could hardly be distinguished even when using 3-generation pedigrees. Imprinting could clearly be detected for mixtures of mainly ASPs and only few AHSPs with the common parent of the imprinted sex, even though no parental genotypes were available. Conclusion: Our results provide guidance to researchers regarding the possibility to estimate trait-model parameters by a MOD score analysis, including the degree of imprinting, with certain types of pedigrees.

At the Large Hadron Collider (LHC), installed electronics will be exposed to a radiation field of mixed particles over a wide range of energies. While Monte Carlo transport codes can be used for calculations and predictions of radiation levels, the complex operation and layout of the LHC accelerator give rise to unavoidable uncertainties. Dedicated radiation monitors are therefore installed in locations of the electronics to provide an online measurement of the radiation levels pertinent to single-event upsets (SEUs). This paper addresses the method that has been applied to calibrate these radiation monitors for their use in mixed radiation fields. New irradiation tests to determine the sensitivity to neutrons from a few megaelectronvolts to 20 MeV will be presented along with additional irradiation tests with high-energy protons .

Heinzmann A, Brugger M, Bierbaum S, Mailaparambil B, Kopp MV, Strauch K. Joint influences of Acidic-Mammalian-Chitinase with Interleukin-4 and Toll-like Receptor-10 with Interleukin-13 in the genetics of asthma. Pediatr Allergy Immunol 2010: 21: e679–e686. © 2010 John Wiley & Sons A/S In the genetics of asthma, single genetic polymorphisms confer only a small individual risk factor. Haplotype-based association analyses, including joint analyses of several candidate genes, might therefore yield more convincing results than single-region statistics. We set out to test for joint influences of asthma genes previously identified in our study population that is acidic mammalian chitinase (AMCase), Toll-like receptor (TLR)-10, and the interleukins IL-4, IL-13, IL-8, and IL-15. In particular, we investigated whether haplotypes at two or three genes show stronger association with the trait than at a single gene alone. We genotyped 26 polymorphisms in 321 asthmatic children and 270 controls. Haplotype-based association analyses were performed by the program FAMHAP. Single-, two-, and three-gene analyses were conducted as well as conditional analyses for pairs of genes. In the two-region analyses, best evidence was found for a joint effect on asthma for AMCase and IL-4 (praw

We describe an approach to calibrate Single Event Effect (SEE)-based detectors in monoenergetic fields and apply the resulting semi-empiric responses to more general mixed-field cases in which a broad variety of particle species and energy spectra are present. The calibration of the response functions is based both on experimental proton (30–200 MeV) and neutron (5–300 MeV) data and considerations derived from Monte Carlo simulations using the FLUKA Monte Carlo code. The application environments include the quasi-monoenergetic neutrons at RCNP, the atmospheric-like VESUVIO spallation spectrum and the CHARM high-energy accelerator test facility. The agreement between the mixed-field response and that predicted through the mono-energetic calibration is within ±30% for the broad variety of cases considered and thus regarded as highly successful for mixed-field monitoring applications.

In the framework of activation calculation of accelerator components with Monte Carlo methods, an unsolved problem is to take spallation products of trace elements and impurities in a bulk material into account. Due to the low probability of spallation reactions with these elements, a large number of primary particles are necessary to obtain some information about their spallation products, which is far from being converged. A new algorithm of treating high energy reactions has been implemented into MCNPX 2.5.0 to overcome these deficiencies. With this algorithm spallation reactions on all constituents of a material will be performed at each high energy interaction. This leads to the production of spallation products from all elements in a material. We will present examples on how this new methodology influences the outcome of activation calculations.

The Large Hadron Collider (LHC) will operate with 7 TeV/c protons with a luminosity of 1034 cm−2 s−1. This requires two beams, each with 2808 bunches. The nominal intensity per bunch is 1.15 × 1011protons and the total energy stored in each beam is 362 MJ. In previous papers, the mechanisms causing equipment damage in case of a failure of the machine protection system was discussed, assuming that the entire beam is deflected onto a copper target. Another failure scenario is the deflection of beam, or part of it, into carbon material. Carbon collimators and beam absorbers are installed in many locations around the LHC close to the beam, since carbon is the material that is most suitable to absorb the beam energy without being damaged. In case of a failure, it is very likely that such absorbers are hit first, for example, when the beam is accidentally deflected. Some type of failures needs to be anticipated, such as accidental firing of injection and extraction kicker magnets leading to a wrong deflection of a few bunches. Protection of LHC equipment relies on the capture of wrongly deflected bunches with beam absorbers that are positioned close to the beam. For maximum robustness, the absorbers jaws are made out of carbon materials. It has been demonstrated experimentally and theoretically that carbon survives the impact of a few bunches expected for such failures. However, beam absorbers are not designed for major failures in the protection system, such as the beam dump kicker deflecting the entire beam by a wrong angle. Since beam absorbers are closest to the beam, it is likely that they are hit first in any case of accidental beam loss. In the present paper we present numerical simulations using carbon as target material in order to estimate the damage caused to carbon absorbers in case of major beam impact.

In this paper we present numerical simulations of interaction of 450 GeV/ c proton beam that is generated by Super Proton Synchrotron (SPS) at CERN, with a solid copper target. These simulations have been carried out using a two-dimensional hydrodynamic computer code, BIG2. This study has been done to assess the damage caused by these highly relativistic protons to equipment including collimators, absorbers and others in case of an uncontrolled accidental release of the beam. In fact a dedicated experimental facility named HiRadMat is under construction at CERN that will allow one to study these problems experimentally. The simulations presented in this paper will be very useful in designing these experiments and later to interpret the experimental results.

Background: The incidence of caesarean section (CS) is steadily rising world-wide. In particular, CS on maternal demand is performed more frequently. In parts, this might be due to insufficient information of pregnant women about neonatal risks of CS. We sought to specify neonatal outcomes following different modes of delivery, i.e. vaginal delivery, primary CS and secondary CS and to define risk factors for respiratory morbidity and hospitalization. Methods: We analysed 2073 births (gestational age > 35 weeks) during a two-year period at a tertiary obstetric and neonatal centre in Germany. Statistical analyses were performed for single parameters by SPSS as well as by logistic regression to account for possible confounders. Furthermore, extensive model calculation was done. Results: Respiratory morbidity was increased following primary and secondary CS (p = 0.001). By multiple logistic regression, the strongest effect on respiratory symptoms was seen with gestational age, each week more in utero reducing the risk by an odds ratio (OR) of 0.69 (95% CI: [0.61; 0.79]; p = 1.9 × 10−8). Furthermore, a significant interaction between mode of delivery and gestational age was found for the risk of respiratory symptoms (p = 0.0035). Conclusion: For every eight newborns delivered by primary CS one more than expected with vaginal delivery is hospitalized. It is highly relevant to recognize that each week of gestational age reduces the risk of respiratory symptoms, especially if primary CS is performed. The higher rate of respiratory morbidity and neonatal admission following CS should be clearly recognized in counselling of pregnant women.

FLUKA is a Monte-Carlo code able to simulate interaction and transport of hadrons, heavy ions and electromagnetic particles from few keV (or thermal neutron) to cosmic ray energies in whichever material. The highest priority in the design and development of the code has always been the implementation and improvement of sound and modern physical models. A summary of the FLUKA physical models is given, while recent developments are described in detail: among the others, extensions of the intermediate energy hadronic interaction generator, refinements in photon cross sections and interaction models, analytical on-line evolution of radio-activation and remnant dose. In particular, new developments in the nucleus–nucleus interaction models are discussed. Comparisons with experimental data and examples of applications of relevance for space radiation are also provided.

Mixed particle and energy radiation fields present at the Large Hadron Collider (LHC) and its accelerator chain are responsible for failures on electronic devices located in the vicinity of the accelerator beam lines. These radiation effects on electronics and, more generally, the overall radiation damage issues have a direct impact on component and system lifetimes, as well as on maintenance requirements and radiation exposure to personnel who have to intervene and fix existing faults. The radiation environments and respective radiation damage issues along the CERN's accelerator chain were studied in the framework of the CERN Radiation to Electronics (R2E) project and are hereby presented. The important interplay between Monte Carlo simulations and radiation monitoring is also highlighted.

In this paper we present a validation of distributed Raman temperature sensing (RDTS) at the CERN high energy accelerator mixed field radiation test facility (CHARM), newly developed in order to qualify electronics for the challenging radiation environment of accelerators and connected high energy physics experiments. By investigating the effect of wavelength dependent radiation induced absorption (RIA) on the Raman Stokes and anti-Stokes light components in radiation tolerant Ge-doped multi-mode (MM) graded-index optical fibers, we demonstrate that Raman DTS used in loop configuration is robust to harsh environments in which the fiber is exposed to a mixed radiation field. The temperature profiles measured on commercial Ge-doped optical fibers is fully reliable and therefore, can be used to correct the RIA temperature dependence in distributed radiation sensing systems based on P-doped optical fibers.

A new mixed-field radiation test facility called CHARM is available at CERN since end of 2014. Its radiation environment is not only representative for accelerators, but also for atmospheric, ground level and space applications.

The first results of distributed optical fiber radiation sensing measurements based on radiation induced attenuation (RIA) at the new mixed-field irradiation facility CHARM are presented.

Chiara Ferrari∗1, Arwa Dabbech1, Oleg Smirnov2,3, Sphesihle Makhathini2, Jonathan S. Kenyon2, Matteo Murgia4, Federica Govoni4, David Mary1, Eric Slezak1, Franco Vazza5, Annalisa Bonafede5, Marcus Bruggen5, Melanie Johnston-Hollitt6, Siamak Dehghan6, Luigina Feretti7, Gabriele Giovannini7,8, Valentina Vacca9, Michael Wise10, Myriam Gitti7,8, Monique Arnaud11, Gabriel W. Pratt11, Kristian Zarb Adami12,13, Sergio Colafrancesco14 1 Laboratoire Lagrange, UMR 7293, UNS, CNRS, OCA, 06300 Nice (FR) 2 Department of Physics and Electronics, Rhodes University, PO Box 94, Grahamstown, 6140 3 SKA South Africa, 3rd Floor, The Park, Park Road, Pinelands, 7405 (ZA) 4 INAF Osservatorio Astronomico di Cagliari, Via della Scienza 5, 09047 Selargius (IT) 5 Universitat Hamburg, Hamburger Sternwarte, Gojenbergsweg 112, D-21029, Hamburg (DE) 6 School of Chemical & Physical Sciences, Victoria University of Wellington, PO Box 600, Wellington, 6140 (NZ) 7 INAF – Istituto di Radioastronomia, Via Gobetti 101, I–40129 Bologna (IT) 8 Dipartimento di Fisica e Astronomia, Universita di Bologna, Via Ranzani 1, I–40127 Bologna (IT) 9 Max Planck Institute for Astrophysics, Karl-Schwarzschild-Str. 1, 85748 Garching (DE) 10 Netherlands Institute for Radio Astronomy (ASTRON), Postbus 2, 7990 AA Dwingeloo (NL) 11 Laboratoire AIM, IRFU/Service d’Astrophysique – CEA F–91191 Gif-sur-Yvette Cedex (FR) 12 Physics Department, University of Malta, Msida, MSD 2080 (MT) 13 Physics Department, University of Oxford, Oxford, OX1 3RH (UK) 14 School of Physics, University of the Witwatersrand, Private Bag 3, 2050-Johannesburg (ZA) E-mail: chiara.ferrari at oca.eu

STUDY DESIGN: Prospective cohort study with chronic low back pain patients at primary care setting. OBJECTIVE: The aim of our study was to identify predictors for transition from localized chronic low back pain to chronic widespread pain in general practice. In contrast to the typically investigated risk factors, this study also focuses intensively on protective factors, which decrease the probability of chronic widespread pain. For this, we investigated the resources resilience and coping strategies, which are suspected as potential protective factors for incident chronic pain syndromes. SUMMARY OF BACKGROUND DATA: In primary care, about a quarter of chronic low back pain (CLBP) patients suffer from chronic widespread pain (CWP). METHODS: Patients suffering from localized chronic low back pain were included and evaluated after a 6 and 12 months follow up period regarding the development of CWP. Potential risk factors (sociodemographic data, pain characteristics, depression, anxiety, somatization), protective factors (resilience, coping strategies), and sample characteristics were assessed at baseline. Predictor identification was done by multivariate logistic regression analysis. RESULTS: The one-year-incidence for the onset of CWP among CLBP patients was 23.8%. We identified the three risk factors female gender, long duration of back pain and a high rate of psychosomatic symptoms for the onset of CWP among CLBP patients. Coping resources and resilience had no impact on the transition from CLBP to CWP. CONCLUSIONS: The results suggest that CWP is no independent entity, but rather a particularly negative occurrence on a continuum of chronic pain. Processes of somatization play a major role in the development of this extreme.

This study focuses on the ion species and energy dependence of the heavy ion SEE cross section in the sub-LET threshold region through a set of experimental data. In addition, a Monte Carlo based model is introduced and applied, showing a good agreement with the data in the several hundred MeV/n range while evidencing large discrepancies with the measurements in the 10-30 MeV/n interval, notably for the Ne ion. Such discrepancies are carefully analyzed and discussed.

This paper explores the relationship between monoenergetic and mixed-field Single Event Latchup (SEL) cross sections, concluding that for components with a very strong energy dependence and highly-energetic environments, test results from monoenergetic or soft mixed-field spectra can significantly underestimate the operational failure rate. We introduce a semi-empirical approach that can be used to evaluate the SEL rate for such environments based on monoenergetic measurements and information or assumptions on the respective sensitive volume and materials surrounding it. We show that the presence of high-Z materials such as tungsten is particularly important in determining the hadron cross section energy dependence for components with relatively large LET thresholds.

A field trial has been performed at the CERN high-energy accelerator-mixed (CHARM) field facility, newly developed for testing devices within accelerator representative radiation environments, to validate the use of Raman-based optical fiber sensors for distributed temperature measurements in highly radiative environments. Experimental results demonstrate that Raman distributed temperature sensors, operating in loop configuration on radiation-tolerant optical fibers, are able to compensate for wavelength-dependent losses and are, therefore, robust to harsh environments, in which a mixed-field radiation, including protons, neutrons, photons, and other particles, is potentially altering the fiber material properties. The temperature profile measured on commercial radiation-tolerant optical fibers shows that a temperature resolution