We present an improved determination of the strange sea distribution in the nucleon with constraints coming from the recent charm production data in neutrino-nucleon deep-inelastic scattering by the ...NOMAD and CHORUS experiments and from charged current inclusive deep-inelastic scattering at HERA. We demonstrate that the results are consistent with the data from the ATLAS and the CMS experiments on the associated production of W super(+ or -) -bosons with c-quarks. We also discuss issues related to the recent strange sea determination by the ATLAS experiment using LHC collider data.
During the shutdown of the CERN Large Hadron Collider in 2013-2014, an additional pixel layer was installed between the existing Pixel detector of the ATLAS experiment and a new, smaller radius beam ...pipe. The motivation for this new pixel layer, the Insertable B-Layer (IBL), was to maintain or improve the robustness and performance of the ATLAS tracking system, given the higher instantaneous and integrated luminosities realised following the shutdown. Because of the extreme radiation and collision rate environment, several new radiation-tolerant sensor and electronic technologies were utilised for this layer. This paper reports on the IBL construction and integration prior to its operation in the ATLAS detector.
We present a readout chip prototype for future pixel detectors with timing capabilities. The prototype is intended for characterizing 4D pixel arrays with a pixel size of 100x100 μm
2
, where the ...sensors are Low Gain Avalanche Diodes (LGADs). The long term focus is towards a possible replacement of disks in the extended forward pixel system (TEPX) of the CMS experiment during the High Luminosity LHC (HL-LHC). The requirements for this ASIC are the incorporation of a Time to Digital Converter (TDC) in the small pixel area, low power consumption, and radiation tolerance up to 5 × 10
15
n
eq
cm
−2
to withstand the radiation levels in the innermost detector modules for 3000 fb
−1
of the HL-LHC (in the TEPX). A prototype has been designed and produced in 110 nm CMOS technology at LFoundry and UMC with different versions of TDC structures, together with a front end circuitry to interface with the sensors. The design of the TDC will be discussed, with the test set-up for the measurements, and the first results comparing the performance of the different structures.
To cope with the challenging environment of the planned high luminosity upgrade of the Large Hadron Collider (HL-LHC), scheduled to start operation in 2029, CMS will replace its entire tracking ...system. The requirements for the tracker are largely determined by the long operation time of 10 years with an instantaneous peak luminosity of up to 7.5 × 1034cm−2s−1 in the ultimate performance scenario. Depending on the radial distance from the interaction point, the silicon sensors will receive a particle fluence corresponding to a non-ionising energy loss of up to Φeq= 3.5 × 1016cm−2. This paper focuses on planar pixel sensor design and qualification up to a fluence of Φeq = 1.4 × 1016cm−2.
For the development of appropriate planar pixel sensors an R&D program was initiated, which includes n+-p sensors on 150mm (6”) wafers with an active thickness of 150µm with pixel sizes of 100×25 µm2 and 50×50 µm2 manufactured by Hamamatsu Photonics K.K. (HPK). Single chip modules with ROC4Sens and RD53A readout chips were made. Irradiation with protons and neutrons, as well was an extensive test beam campaign at DESY were carried out. This paper presents the investigation of various assemblies mainly with ROC4Sens readout chips. It demonstrates that multiple designs fulfil the requirements in terms of breakdown voltage, leakage current and efficiency. The single point resolution for 50×50 µm2 pixels is measured as 4.0µm for non-irradiated samples, and 6.3µm after irradiation to Φeq = 7.2 × 1015cm−2.
The upgrade of the LHC to the High-Luminosity LHC (HL-LHC) is expected to increase the LHC design luminosity by an order of magnitude. This will require silicon tracking detectors with a ...significantly higher radiation hardness. The CMS Tracker Collaboration has conducted an irradiation and measurement campaign to identify suitable silicon sensor materials and strip designs for the future outer tracker at the CMS experiment. Based on these results, the collaboration has chosen to use n-in-p type silicon sensors and focus further investigations on the optimization of that sensor type. This paper describes the main measurement results and conclusions that motivated this decision.
Drugs in the environment: Do we know the risks? Caminada, S L; Caminada, M L; Bocchiglieri, M M ...
European journal of public health,
09/2020, Letnik:
30, Številka:
Supplement_5
Journal Article
Recenzirano
Odprti dostop
Abstract
The occurrence of residual drugs in sewage and natural waters is an important international topic. The behavior of compounds in the environment and sewage treatment plants (ETEs) is ...influenced by their physicochemical properties, which govern partition in water, soil or biota.
The present study aims to identify the presence of clonazepan, simvastatin, paracetamol, atenolol, carbamazepine and fluoxetine drugs in biosolid from TEE before and after the composting process.
Based on the Environmental Protection Agency's Structure-Activity Relationship Model (ECOSAR) Program (EPA), and according to ZAGATTO (2006), the octanol/water partition coefficient (Kow) observed for ibuprofen drugs, fluoxetine and sinvastanin was 3.97, 3.82 and 4.68, respectively, denoting its bioaccumulation potential, which does not happen with the other compounds, as they present logKow < 3, being log kow = 0.03 for atenolol; 2.3 for carbamazepine; 0.49 for paracetamol and 2.53 for clorazepam.
AQUINO, 2013, mentions that drugs with logKow < 2.5 have high hydrophylycity and low absorption trend in biomass and lipid fractions of suspended solids. For Log Kow values between 2.5 and 4.0, there is a moderate tendency of absorption in these matrices.
Data on ecotoxicity, provided by the ECOSAR program, indicate the effects observed in fish, at the concentration of 30 μg/L for Sinvastatin and 20 μg/L for Fluoxetine.
The agricultural use of biosolids is a controversial subject due to the potential adverse impacts on human health. In the name of safety, strict standards, high quality criteria and restrictions on use are imposed, and standards should be based on risk assessment, but there is a lack of data on the subject, and there is still no clarity as to what constitutes tolerable risk in the brazilian context for the composition of a pattern.
Key messages
According to the results obtained, it is verified that the studied compounds have the potential to cause deleterious effects on the evaluated organisms, according to the ECOSAR model. Considering the little information available on the subject, especially in relation to the incidence and persistence of drugs in the environment, the continuity of studies is necessary.
The high luminosity upgrade of the Large Hadron Collider, foreseen for 2026, necessitates the replacement of the CMS experiment’s silicon tracker. The innermost layer of the new pixel detector will ...be exposed to severe radiation, corresponding to a 1 MeV neutron equivalent fluence of up to
Φ
e
q
=
2
×
10
16
cm
-
2
, and an ionising dose of
≈
5
MGy after an integrated luminosity of 3000 fb
-
1
. Thin, planar silicon sensors are good candidates for this application, since the degradation of the signal produced by traversing particles is less severe than for thicker devices. In this paper, the results obtained from the characterisation of 100 and 200
μ
m thick p-bulk pad diodes and strip sensors irradiated up to fluences of
Φ
e
q
=
1.3
×
10
16
cm
-
2
are shown.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Impact of low-dose electron irradiation on n+p silicon strip sensors Adam, W.; Baulieu, G.; Boudoul, G. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/2015, Letnik:
803, Številka:
C
Journal Article
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The response of n+p silicon strip sensors to electrons from a 90Sr source was measured using a multi-channel read-out system with 25ns sampling time. The measurements were performed over a period of ...several weeks, during which the operating conditions were varied. The sensors were fabricated by Hamamatsu Photonics on 200μm thick float-zone and magnetic-Czochralski silicon. Their pitch was 80μm, and both p-stop and p-spray isolation of the n+ strips were studied. The electrons from the 90Sr source were collimated to a spot with a full-width-at-half-maximum of 2mm at the sensor surface, and the dose rate in the SiO2 at the maximum was about 50Gy(SiO2)/d. After only a few hours of making measurements, significant changes in charge collection and charge sharing were observed. Annealing studies, with temperatures up to 80°C and annealing times of 18h showed that the changes can only be partially annealed. The observations can be qualitatively explained by the increase of the positive oxide-charge density due to the ionization of the SiO2 by the radiation from the β source. TCAD simulations of the electric field in the sensor for different oxide-charge densities and different boundary conditions at the sensor surface support this explanation. The relevance of the measurements for the design of n+p strip sensors is discussed.
A new pixel detector for the CMS experiment was built in order to cope with the instantaneous luminosities anticipated for the Phase I Upgrade of the LHC . The new CMS pixel detector provides ...four-hit tracking with a reduced material budget as well as new cooling and powering schemes. A new front-end readout chip mitigates buffering and bandwidth limitations, and allows operation at low comparator thresholds. In this paper, comprehensive test beam studies are presented, which have been conducted to verify the design and to quantify the performance of the new detector assemblies in terms of tracking efficiency and spatial resolution. Under optimal conditions, the tracking efficiency is 99.95 ± 0.05%, while the intrinsic spatial resolutions are 4.80 ± 0.25 μm and 7.99 ± 0.21 μm along the 100 μm and 150 μm pixel pitch, respectively. The findings are compared to a detailed Monte Carlo simulation of the pixel detector and good agreement is found.
The measurement of the luminosity recorded by the CMS detector installed at LHC interaction point 5, using proton–proton collisions at
s
=
13
TeV
in 2015 and 2016, is reported. The absolute ...luminosity scale is measured for individual bunch crossings using beam-separation scans (the van der Meer method), with a relative precision of 1.3 and 1.0% in 2015 and 2016, respectively. The dominant sources of uncertainty are related to residual differences between the measured beam positions and the ones provided by the operational settings of the LHC magnets, the factorizability of the proton bunch spatial density functions in the coordinates transverse to the beam direction, and the modeling of the effect of electromagnetic interactions among protons in the colliding bunches. When applying the van der Meer calibration to the entire run periods, the integrated luminosities when CMS was fully operational are 2.27 and 36.3
fb
-
1
in 2015 and 2016, with a relative precision of 1.6 and 1.2%, respectively. These are among the most precise luminosity measurements at bunched-beam hadron colliders.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
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