The MERLINO project is developing a multi-detector setup with the goal of evaluating the beam stopping power from Prompt-Gamma-Timing measurements in proton therapy. The detectors are based on the ...cerium-doped lanthanum bromide crystal, LaBr3:Ce, coupled to photo-multiplier tubes. The system characterization is ongoing and the first calibration measurements with two detectors showed 124 ps σ and σE/E = 3% for the timing and energy resolution, respectively. The measured experimental parameters were then used to carry out a preliminary estimation of the stopping power. Results from the simulation of a 189 MeV proton beam impinging on an homogeneous phantom are presented for the optimisation of the MERLINO detector setup.
Abstract
In the framework of the upgrade of the Pierre Auger
Observatory, a new high voltage module is being employed for the
power supply of the 1-inch photomultiplier added to each
water-Cherenkov ...detector of the surface array with the aim of
increasing the dynamic range of the measurements. This module is
located in a dedicated box near the electronics and comprises a low
consumption DC-DC converter hosted inside an aluminum box. All the
modules have undergone specific tests to verify their reliability in
the extreme environmental conditions of the Argentinian pampa. In
this paper, we describe the validation procedure and the facility
developed to this aim. The successful results of the tests on the
HVPS modules are presented and discussed.
With the forthcoming of space borne observatories devoted to research Ultra High Energy Cosmic Rays (UHECR) in the decade of 1020eV, new challenges are posed to the experimental techniques. Mounted ...on the International Space Station, the Extreme Universe Space Observatory on board the Japanese Experimental Module (JEM-EUSO) will rely on the well established fluorescence technique to observe Extensive Air Showers(EAS) propagating in the atmosphere from space. The EUSO Simulation and Analysis Framework (ESAF) has been developed in this context to provide a full end-to-end simulation frame. Within ESAF the angular reconstruction modules rely on an a priori knowledge of the photoelectrons that were produced by an EAS and were also detected by the focal surface. Therefore, there is the need for a tool that discriminates between EAS-photoelectrons and background. In this paper we discuss the Peak and WIndow SEarching (PWISE) technique, which we have implemented inside ESAF as a module to perform the discrimination of the EAS photoelectrons. This is essential since the angular reconstruction modules rely on the knowledge of the EAS-photoelectrons. We also present some first results of the angular reconstruction using this module within ESAF.
In this paper we describe the expected performance of JEM-EUSO. Designed as the first mission to explore the ultra-high energy universe from space, JEM-EUSO will monitor the Earth’s atmosphere at ...night to record the UV (300–430nm) tracks generated by the extensive air showers produced by ultra-high energy primary particles developing in the atmosphere. Studies of the expected aperture, the estimated exposure, as well as on the methods to infer arrival direction, energy, and Xmax of primary particles are presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
To determine the relationship between different body positions during recumbency on the cranial migration of epidurally injected methylene blue in canine cadavers.
21 fresh cadavers of clinically ...normal adult female mixed-breed dogs.
Dogs were randomly assigned to the following 3 groups: dogs remaining in right lateral recumbency (n = 7), dogs rotated from left to right lateral recumbency (7), and dogs rotated from dorsal to right lateral recumbency (7). Each dog received an epidural injection of 0.05% methylene blue (0.1 mL/kg) at the lumbosacral space. A dorsal laminectomy of the vertebral column was made, and cranial extent of methylene blue in 4 quadrants (right lateral, left lateral, ventral, and dorsal) was determined by examining dura mater staining.
No significant difference was found among groups in regard to body weight or body condition score. Epidural cranial migration of methylene blue in the right lateral quadrant was significantly greater in dogs that remained in right lateral recumbency than in dogs that were rotated from left to right lateral recumbency. No significant difference was found within groups for epidural cranial migration of methylene blue between each quadrant. No significant relationship was found between body weight or body condition score and epidural cranial migration of methylene blue.
Body positioning and amount of recumbency time influence cranial migration of epidurally injected methylene blue. If greater cranial migration of an epidurally administered drug is desired, placing the patient in lateral recumbency with the surgical site on the dependent side may precede surgery.
The Pierre Auger Cosmic Ray Observatory Aab, A.; Abreu, P.; Aglietta, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2015, Volume:
798, Issue:
C
Journal Article
Peer reviewed
Open access
The Pierre Auger Observatory, located on a vast, high plain in western Argentina, is the world׳s largest cosmic ray observatory. The objectives of the Observatory are to probe the origin and ...characteristics of cosmic rays above 1017eV and to study the interactions of these, the most energetic particles observed in nature. The Auger design features an array of 1660 water Cherenkov particle detector stations spread over 3000km2 overlooked by 24 air fluorescence telescopes. In addition, three high elevation fluorescence telescopes overlook a 23.5km2, 61-detector infilled array with 750m spacing. The Observatory has been in successful operation since completion in 2008 and has recorded data from an exposure exceeding 40,000km2sryr. This paper describes the design and performance of the detectors, related subsystems and infrastructure that make up the Observatory.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models without relying on the ...absolute energy calibration, and apply it to events with primary energy 6-16 EeV (E_{CM}=110-170 TeV), whose longitudinal development and lateral distribution were simultaneously measured by the Pierre Auger Observatory. The average hadronic shower is 1.33±0.16 (1.61±0.21) times larger than predicted using the leading LHC-tuned models EPOS-LHC (QGSJetII-04), with a corresponding excess of muons.
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Using the data taken at the Pierre Auger Observatory between December 2004 and December 2012, we have examined the implications of the distributions of depths of atmospheric shower maximum (X ...sub(max)), using a hybrid technique, for composition and hadronic interaction models. We do this by fitting the distributions with predictions from a variety of hadronic interaction models for variations in the composition of the primary cosmic rays and examining the quality of the fit. Regardless of what interaction model is assumed, we find that our data are not well described by a mix of protons and iron nuclei over most of the energy range. Acceptable fits can be obtained when intermediate masses are included, and when this is done consistent results for the proton and iron-nuclei contributions can be found using the available models. We observe a strong energy dependence of the resulting proton fractions, and find no support from any of the models for a significant contribution from iron nuclei. However, we also observe a significant disagreement between the models with respect to the relative contributions of the intermediate components.
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The Advanced LIGO and Advanced Virgo observatories recently discovered gravitational waves from a binary neutron star inspiral. A short gamma-ray burst (GRB) that followed the merger of this binary ...was also recorded by the Fermi Gamma-ray Burst Monitor (Fermi-GBM), and the Anti-Coincidence Shield for the Spectrometer for the International Gamma-Ray Astrophysics Laboratory (INTEGRAL), indicating particle acceleration by the source. The precise location of the event was determined by optical detections of emission following the merger. We searched for high-energy neutrinos from the merger in the GeV-EeV energy range using the Antares, IceCube, and Pierre Auger Observatories. No neutrinos directionally coincident with the source were detected within 500 s around the merger time. Additionally, no MeV neutrino burst signal was detected coincident with the merger. We further carried out an extended search in the direction of the source for high-energy neutrinos within the 14 day period following the merger, but found no evidence of emission. We used these results to probe dissipation mechanisms in relativistic outflows driven by the binary neutron star merger. The non-detection is consistent with model predictions of short GRBs observed at a large off-axis angle.
We present a new method for probing the hadronic interaction models at ultrahigh energy and extracting details about mass composition. This is done using the time profiles of the signals recorded ...with the water-Cherenkov detectors of the Pierre Auger Observatory. The profiles arise from a mix of the muon and electromagnetic components of air showers. Using the risetimes of the recorded signals, we define a new parameter, which we use to compare our observations with predictions from simulations. We find, first, inconsistencies between our data and predictions over a greater energy range and with substantially more events than in previous studies. Second, by calibrating the new parameter with fluorescence measurements from observations made at the Auger Observatory, we can infer the depth of shower maximum Xmax for a sample of over 81,000 events extending from 0.3 to over 100 EeV. Above 30 EeV, the sample is nearly 14 times larger than what is currently available from fluorescence measurements and extending the covered energy range by half a decade. The energy dependence of ⟨Xmax⟩ is compared to simulations and interpreted in terms of the mean of the logarithmic mass. We find good agreement with previous work and extend the measurement of the mean depth of shower maximum to greater energies than before, reducing significantly the statistical uncertainty associated with the inferences about mass composition.
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