Space radiation can affect performance of electronic components during a satellite’s mission. In order to ensure reliable performance, these components must be tested under some types of radiation. ...Middle East Technical University-Defocusing Beam Line (METU-DBL) project aims to perform Single Event Effect (SEE) tests for space, HiLumi LHC, nuclear and other applications. ESA ESCC No. 25100 Standard Single Event Effect Test Method and Guidelines is considered for these SEE tests. Turkish Atomic Energy Authority (TAEA) has a cyclotron which can accelerate protons up to 30MeV kinetic energy at the Proton Accelerator Facility (PAF) mainly for radioisotope production and for R&D purposes. According to the standard, the proton beam kinetic energy must be between 20MeV and 200MeV. While the proton energy is suitable for SEE tests, the beam size must be 15.40 cm × 21.55 cm and the flux must be between 105 p/cm2/s to at least 108 p/cm2/s according to the standard. The beam size at the entrance of the R&D room is mm-sized and the current is variable between 10 μA and 1.2 mA. Therefore, a defocusing beam line has been designed to enlarge the beam size and reduce the flux. The beam line has three quadrupole magnets to enlarge the beam size and collimators and scattering foils are used for flux reduction. Currently, METU-DBL preliminary test setup, which was installed in the R&D room, enlarges the beam size with only two quadrupole magnets and it reduces the proton flux with a collimator. The final beam size is about 6 cm × 8 cm and the beam flux is ∼109 p/cm2/s. The first tests of electronic components were performed and the commissioning results from the beam measurement system are here presented.
In the framework of CERN neutrino platform project at the CERN SPS North Area, two new beam lines have been designed as extensions of the existing secondary beam lines, able to provide low energy ...particles in the momentum range of 0.4 to 12GeV/c . The layout of these very low energy beam lines, their design parameters as well as outlook on their expected performance, are summarized in this paper.
Thermal neutron measurements by Timepix detector in H4IRRAD at CERN Biskup, B.; Brugger, M.; Calviani, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
11/2019, Letnik:
944
Journal Article
Recenzirano
Timepix, a pixel detector, was installed in the H4IRRAD irradiation area at CERN to study its response to a mixed radiation field. The measured data were compared to Monte Carlo simulations performed ...by the FLUKA code. This paper focuses on thermal neutron fluence measurement and simulation studies. The observed disagreement between the measured and simulated thermal neutron fluence of a factor 2.6 is discussed and the influence of the shielding material composition on this disagreement is studied.
The interaction of dust particles with the LHC proton beams accounts for a major fraction of irregular beam loss events observed in LHC physics operation. The events cease after a few beam ...revolutions because of the expulsion of dust particles from the beam once they become ionized in the transverse beam tails. Despite the transient nature of these events, the resulting beam losses can trigger beam aborts or provoke quenches of superconducting magnets. In this paper, we study the characteristics of beam-dust particle interactions in the cryogenic arcs by reconstructing key observables like nuclear collision rates, loss durations and integral losses per event. The study is based on events recorded during 6.5 TeV operation with stored beam intensities of up to∼3×1014protons per beam. We show that inelastic collision rates can reach almost1012collisions per second, resulting in a loss of up to∼1.6×108protons per event. We demonstrate that the experimental distributions and their dependence on beam parameters can be described quantitatively by a previously developed simulation model if dust particles are assumed to be attracted by the beam. The latter finding is consistent with recent time profile studies and yields further evidence that dust particles carry a negative charge when entering the beam. We also develop different hypotheses regarding the absence of higher-loss events in the measurements, although such events are theoretically not excluded by the simulation model. The results provide grounds for predicting dust-induced beam losses in the presence of higher-intensity beams in future runs of the High-Luminosity LHC.
In this paper, we present the physics performance of the ESSnuSB experiment in the standard three flavor scenario using the updated neutrino flux calculated specifically for the ESSnuSB configuration ...and updated migration matrices for the far detector. Taking conservative systematic uncertainties corresponding to a normalization error of Formula omitted for signal and Formula omitted for background, we find that there is Formula omitted Formula omitted CP violation discovery sensitivity for the baseline option of 540 km (360 km) at Formula omitted. The corresponding fraction of Formula omitted for which CP violation can be discovered at more than Formula omitted is Formula omitted. Regarding CP precision measurements, the Formula omitted error associated with Formula omitted is around Formula omitted and with Formula omitted is around Formula omitted Formula omitted for the baseline option of 540 km (360 km). For hierarchy sensitivity, one can have Formula omitted sensitivity for 540 km baseline except Formula omitted and Formula omitted sensitivity for 360 km baseline for all values of Formula omitted. The octant of Formula omitted can be determined at Formula omitted for the values of: Formula omitted ( Formula omitted and Formula omitted) for baseline of 540 km (360 km). Regarding measurement precision of the atmospheric mixing parameters, the allowed values at Formula omitted are: Formula omitted ( Formula omitted) and Formula omitted eV Formula omitted eV Formula omitted ( Formula omitted eV Formula omitted eV Formula omitted) for the baseline of 540 km (360 km).
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract Relativistic electron-positron plasmas are ubiquitous in extreme astrophysical environments such as black-hole and neutron-star magnetospheres, where accretion-powered jets and pulsar winds ...are expected to be enriched with electron-positron pairs. Their role in the dynamics of such environments is in many cases believed to be fundamental, but their behavior differs significantly from typical electron-ion plasmas due to the matter-antimatter symmetry of the charged components. So far, our experimental inability to produce large yields of positrons in quasi-neutral beams has restricted the understanding of electron-positron pair plasmas to simple numerical and analytical studies, which are rather limited. We present the first experimental results confirming the generation of high-density, quasi-neutral, relativistic electron-positron pair beams using the 440 GeV/c beam at CERN’s Super Proton Synchrotron (SPS) accelerator. Monte Carlo simulations agree well with the experimental data and show that the characteristic scales necessary for collective plasma behavior, such as the Debye length and the collisionless skin depth, are exceeded by the measured size of the produced pair beams. Our work opens up the possibility of directly probing the microphysics of pair plasmas beyond quasi-linear evolution into regimes that are challenging to simulate or measure via astronomical observations.
In this paper, we study scalar mediator induced nonstandard interactions (SNSIs) in the context of the ESSnuSB experiment. In particular, we study the capability of ESSnuSB to put bounds on the SNSI ...parameters and also study the impact of SNSIs in the measurement of the leptonic C P phase δ C P . Existence of SNSIs modifies the neutrino mass matrix and this modification can be expressed in terms of three diagonal real parameters ( η e e , η μ μ , and η τ τ ) and three off-diagonal complex parameters ( η e μ , η e τ , and η μ τ ). Our study shows that the upper bounds on the parameters η μ μ and η τ τ depend upon how Δ m 31 2 is minimized in the theory. However, this is not the case when one tries to measure the impact of SNSIs on δ C P . Further, we show that the C P sensitivity of ESSnuSB can be completely lost for certain values of η e e and η μ τ for which the appearance channel probability becomes independent of δ C P . Published by the American Physical Society 2024
Abstract
The Middle East Technical University Defocusing Beamline
(METU-DBL) is designed to deliver protons with selectable kinetic
energies between 15–30 MeV, and proton flux
between 10
6
–10
10
...protons/cm
2
/s, on a
maximum 21.55 to 15.40 cm target region with a beam uniformity
within ±6%, in accordance with the ESA ESCC No. 25100
specification for single event effects (SEEs) tests in the low
energy range. The achieved high proton fluences, allow users to test
space-grade materials; electronic circuits, ASICs, FPGAs, optical
lenses, structural elements, and coating layers for LEO, GEO, and
interplanetary missions.
The total received dose on the Device-Under-Test (DUT) from
secondary particles created during proton-material interactions at
the first beam collimator and the beam dump never exceed 0.1% of
the dose from primary protons. The METU-DBL is equiped with several
measurement stations and services to the user teams. A secondary
measurement station in a rotating drum that can hold multiple
samples has been constructed next to the first collimator which
provides neutrons for transmission experiments. At the target
region, a robotic table is located, which provides mechanical and
electrical mounting points to the samples and allows multiple
samples to be tested in a row. A modular vacuum box can also be
attached on the robotic table for any test that may require a vacuum
environment. Power rails on the robotic table provide various
outputs for the DUT. For the data acquisition, high-speed networking
and a modular industrial PC are available at the target station. The
design of the METU-DBL control software enables test users to
integrate and optimize the data acquisition and controlling of the
DUT.
The beam properties at the target region are measured with the
diamond, Timepix3, and fiber scintillator detectors mounted on the
robotic table. With diamond and Timepix3 detectors, measurements are
taken from the five different points (center and the four corners)
of the test area to measure the proton flux and ensure that it is
uniform across the full test area. Fiber scintillators on both axes
(X and Y) scan the target area to cross-check the beam profile's
uniformity. Secondary doses during the irradiation are measured by a
Geiger-Müller tube sensitive to electrons and gammas above
0.1 MeV and by a neutron detector located at the entrance of the
R&D room. The room cools down relatively fast after any irradiation
(<1 hour).
Accurate linear energy deposition rates and absorbed doses on the
samples are calculated using MCNP6, FLUKA and Geant4 Monte Carlo
simulations. Alanine dosimetry measurements that are calibrated
against these simulations are also used to estimate the absorbed
dose on the sample.
Operating at 6.5 TeV, the LHC surpassed the expectations and delivered an average of 66 fb-1 integrated luminosity to the two high luminosity experiments ATLAS and CMS by the end of 2018. In order to ...provide a continuous feedback to the machine coordination for further optimizing the performance, an automated tool for monitoring the main beam parameters and machine configurations, has been devised and extensively used. New features like the coupling between the two planes and effects of noise, were added to the numerical model used since 2016 to calculate the machine luminosity. Estimates, based both on simulations and on observed beam parameters, were reported fill-by-fill as well as in overall trends during the year. Highlights of the observations including the observed additional emittance blow up (on top of IBS, SR and elastic scattering) as well as additional losses (on top of the expected proton burn off) are presented for the 2018 data. Finally, cumulated integrated luminosity projections from the model for the entire 2018 data based on different degradation mechanisms are compared also with respect to the achieved luminosity.
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