The CLAS12 Geant4 simulation Ungaro, M.; Angelini, G.; Battaglieri, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2020, Volume:
959, Issue:
C
Journal Article
Peer reviewed
Open access
The Geant4 Monte-Carlo (GEMC) package is used to simulate the passage of particles through the various CLAS12 detectors. The geometry is implemented through a database of Geant4 volumes created ...either through the GEMC native API, by the CLAS12 geometry service, or imported from the CAD engineering model. The truth information is digitized with a plugin mechanism by routines specific to each detector and includes the use of the CLAS12 calibration database constants to produce both ADC and TDC response functions. Theoretical models that produce the generated events interface with GEMC through the LUND data format. The merging of simulated data with real random trigger data provides a mechanism to include both beam and electronic background into the simulation of generated events to accurately model beam data from the CLAS12 detector. The performance of simulation is demonstrated by comparison with the experimental data.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
In this research, different magnetic treatments were applied to diesel fuel using static magnetic fields of 0.36T of magnetic induction. The magnetic conditioners (MCs) were installed in different ...positions of the fuel lines in the engine and the magnetic treatment of the diesel was also carried out before introducing it into the engine tanks. The study was conducted using a four-stroke, two-cylinder, Lister Petter (LPWS2) engine with a compression ratio of 23.5:1 and a constant engine speed of 1500 rpm. The emissions of carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2), nitrogen oxides and the temperature of the exhaust gases and the mass consumption of fuel were measured. The highest levels of reduction were achieved with the magnetic treatments that locate the MC directly in the engine's pipes. As the number of MC in the engine pipes increases, the emissions of polluting gases decrease. With the treatment that locates one MC in front of each injector, two MC at the entrance of the filter and two MC in the return of fuel were able to increase the O2 emissions by 6.9% and decrease the CO emissions in about 21.3% in the last load of the generator set. With this treatment a decrease in fuel consumption of 4.89% to 80% of engine load was obtained.
Light dark matter searches with positrons Battaglieri, M.; Bianconi, A.; Bisio, P. ...
European physical journal. A, Hadrons and nuclei,
08/2021, Volume:
57, Issue:
8
Journal Article
Peer reviewed
Open access
We discuss two complementary strategies to search for light dark matter (LDM) exploiting the positron beam possibly available in the future at Jefferson Laboratory. LDM is a new compelling hypothesis ...that identifies dark matter with new sub-GeV “hidden sector” states, neutral under standard model interactions and interacting with our world through a new force. Accelerator-based searches at the intensity frontier are uniquely suited to explore it. Thanks to the high intensity and the high energy of the Continuous Electron Beam Accelerator Facility (CEBAF) beam, and relying on a novel LDM production mechanism via positron annihilation on target atomic electrons, the proposed strategies will allow us to explore new regions in the LDM parameters space, thoroughly probing the LDM hypothesis as well as more general hidden sector scenarios.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Enhanced UV light detection using a p-terphenyl wavelength shifter Joosten, S.; Kaczanowicz, E.; Ungaro, M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2017, Volume:
870, Issue:
C
Journal Article
Peer reviewed
Open access
UV-glass photomultiplier tubes (PMTs) have poor photon detection efficiency for wavelengths below 300 nm due to the opaqueness of the window material. Costly quartz PMTs could be used to enhance the ...efficiency below 300 nm. A less expensive solution that dramatically improves this efficiency is the application of a thin film of a p-terphenyl (PT) wavelength shifter on UV-glass PMTs. This improvement was quantified for Photonis XP4500B PMTs for wavelengths between 200 nm and 400 nm. The gain factor ranges up to 5.4±0.5 at a wavelength of 215 nm, with a material load of 110±10μg∕cm2 (894 nm). The wavelength shifter was found to be fully transparent for wavelengths greater than 300 nm. The resulting gain in detection efficiency, when used in a typical C̆erenkov counter, was estimated to be of the order of 40%. Consistent coating quality was assured by a rapid gain testing procedure using narrow-band UV LEDs. Based on these results, 200 Photonis XP4500B PMTs were treated with PT for the upgraded low-threshold C̆erenkov counter (LTCC) to be used in the CEBAF Large Acceptance Spectrometer upgraded detector (CLAS12) at the Thomas Jefferson National Accelerator Facility.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The whole Extreme Energy Events (EEE) array is composed of 61 telescopes installed in Italian High Schools, built and operated by students and teachers, constantly supervised by researchers. The muon ...telescope of the EEE Project is made by 3 Multigap Resistive Plate Chambers (MRPC). The unconventional working sites are a unique test field for checking the robustness and the low-ageing features of the MRPC technology for particle tracking and timing purposes. The MRPCs are fluxed with a standard mixture (98% C
2
H
2
F
4
- 2% SF
6
) of greenhouse gases (GHG) phasing out of production. The EEE Collaboration is currently studying alternative mixtures environmentally and economically sustainable. The EEE Collaboration actions to reduce the Global Warming Potential (GWP) in the MRPC array of the EEE experiment are progressing.
According to data analyzed from the Gallup Daily Tracking Politics and Economy survey between 2015 and 2017, nearly half (46.7%) of LGBT adults in the U.S. are religious, and just over half (53.3%) ...of LGBT adults are not religious. The majority who identified as religious attend Protestant churches. The Pentecostal church is a member of the Protestant Christian tradition. In a Constructivist Grounded Theory study of six U.S. gay male, Pentecostal Christians, our study excavates and chronicles their journey toward wholeness. Three major themes emerged from our study: embracing the journey, belonging to a community, and living unapologetically. From these themes, we learned that wholeness becomes possible when gay male Christians can form identities that are uniquely and holistically their own. We used these themes as a clarion call for clinicians who engage with clients encountering a conflict between their religious/spiritual tradition and their sexual orientation to actively assist their clients with reducing the dissonance they experience.
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BFBNIB, NUK, PILJ, SAZU, UL, UM, UPUK
7.
Performance of the CLAS12 Silicon Vertex Tracker modules Antonioli, M.A.; Boiarinov, S.; Bonneau, P. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2013, Volume:
732
Journal Article
Peer reviewed
Open access
For the 12GeV upgrade, the CLAS12 experiment has designed a Silicon Vertex Tracker (SVT) using single sided microstrip sensors fabricated by Hamamatsu. The sensors have graded angle design to ...minimize dead areas and a readout pitch of 156μm, with intermediate strip. Double sided SVT module hosts three daisy-chained sensors on each side with a full strip length of 33cm. There are 512 channels per module read out by four Fermilab Silicon Strip Readout (FSSR2) chips featuring data driven architecture, mounted on a rigid-flex hybrid. Modules are assembled on the barrel using unique cantilevered geometry to minimize the amount of material in the tracking volume. Design and performance of the SVT modules are presented, focusing on results of electrical measurements.
•A Silicon Vertex Tracker has been designed for the central tracker of the CLAS12 experiment.•Using cantilevered module geometry allows minimizing amount of material in the tracking volume.•A dedicated Hybrid Flex Circuit Board has been developed to read out double sided module.•Module performance meets design goals of the CLAS12 Central Tracker.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Gitelman syndrome Ungaro, Catalina M; Odstrcil-Bobillo, M Silvina; Russo, Paula M
Medicina,
02/2020, Volume:
80, Issue:
1
Journal Article
Peer reviewed
Gitelman syndrome is one of the salt losing tubulopathies. Hypokalemia and hypomagnesemia appear in the setting of the partial blockade of salt absorption in the distal tubule. We conducted a ...descriptive study of a case series of five patients with Gitelman syndrome (4 women, from 28 to 85 years) in our institution, between the years 2004 and 2015. The most frequent form of diagnosis in our series was by laboratory finding. The only acknowledged clinical symptom was malaise. Regarding laboratory findings, the mean potassemia was of 2.5 ± 0.5 mmol/l, with a minimum value of 2.1 mmol/l. Additionally, the serum magnesium value was of 1.3 ± 0.3 mg/dl. In conclusion, we observed that the forms of presentation consist of biochemical alterations with or without nonspecific manifestations, which currently represents the greatest diagnostic difficulty and reinforces the importance to achieve a timely diagnosis, especially in young patients with critical serum potassium values.
Abstract Introduction Chronic Obstructive Pulmonary Disease (COPD) is the fifth cause of mortality worldwide. Systemic inflammation is a crucial element in its physiopathology. As Renin-Angiotensin ...System is one of the main components of this inflammatory neurohumoral cascade, Angiotensin Receptor Blockers (ARBs) might have an effect on mortality in COPD patients. Goal To evaluate the association between ARBs treatment and mortality in COPD patients. Methods Retrospective cohort of patients with diagnosis of COPD from 2003 to 2013. COPD cases were detected according to the diagnosis by treating physicians in any field of the electronic clinical health records by controlled vocabulary in patients older than 18 years affiliated to the Hospital Italiano de Buenos Aires (HIBA) Health Plan. Patients were classified in two groups depending on their use of ARBs according to the hospital pharmacy records. The mortality registry of the HIBA was used to obtain the event of death. The 8 year survival experience was described using Kaplan Meier estimator and survival curve comparisons were calculated with the Cox Mantel test. Hazard Ratios (HR) were estimated using a Cox proportional risk model. A propensity score (PS) was developed for the use of ARBs. Results 1140 deaths were detected, 1063 in the no exposure group and 77 in the ARBs exposure group. The 8 year survival was 71% (CI 95% 69–72%). The survival in the non exposed group was 71% (CI 95% 69–73%) and 76% (CI 95% 0,69-0,81) in the ARBs exposed group. The unadjusted HR for mortality was 0.85 (CI 95% 0.67–1.07, p = 0.17) and the adjusted HR by PS was 0.63 (CI 95% 0.50–0.80, p < 0.001). Discussion ARBs use seems to be associated to a lower mortality in patients with COPD. Additional studies are needed to corroborate this finding.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Short-range correlated (SRC) nucleon pairs are a vital part of the nucleus, accounting for almost all nucleons with momentum greater than the Fermi momentum (k_{F}). A fundamental characteristic of ...SRC pairs is having large relative momenta as compared to k_{F}, and smaller center of mass (c.m.) which indicates a small separation distance between the nucleons in the pair. Determining the c.m. momentum distribution of SRC pairs is essential for understanding their formation process. We report here on the extraction of the c.m. motion of proton-proton (pp) SRC pairs in carbon and, for the first time in heavier and ansymetric nuclei: aluminum, iron, and lead, from measurements of the A(e,e^{'}pp) reaction. We find that the pair c.m. motion for these nuclei can be described by a three-dimensional Gaussian with a narrow width ranging from 140 to 170 MeV/c, approximately consistent with the sum of two mean-field nucleon momenta. Comparison with calculations appears to show that the SRC pairs are formed from mean-field nucleons in specific quantum states.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM
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