K. Dilsiz

Advanced radiation applications have been widely used and extended to many fields. As a result of this fact, choosing an appropriate shielding material based on the radiation application has become vital. In this regard, the integration of elements into polymer composites has been investigated and contributed to the quantity and quality of radiation shielding materials. This study reports photon attenuation parameters and electromagnetic shielding effectiveness of a novel polymer composite prepared with a matrix reinforced with three different proportions (5, 10, and 15 wt%) of niobium content. Addition of Nb dopant improves both photon attenuation and electromagnetic shielding effectiveness for the investigated composites. Therefore, Nb(15%) polymer composite with highest concentration has been found to be the best absorber for ionizing and non-ionizing radiations. Consequently, the performed analyzes provide evidences that the prepared Nb-reinforced polymer composite could be effectively used as photon radiation attenuator and electromagnetic shielding material.

Researches on advanced composites to protect environment health towards radioactive pollution have drawn attention with the rising use of radioactive elements. From this point, polymer micro composites are quite encouraging in terms of multifunctional properties in mechanical, electrical, thermal, as well as nuclear shielding. The present study has explored the efficacy of micro lead (Pb) loaded polymer composites for radio protective applications such as a fabrication of protective enclosures. High energetic photon shielding experiments have been applied through gamma spectrometer equipped with HPGe detector and various radioactive point sources namely 137Cs, 22Na, 152Eu, 133Ba, 241Am and 57,60Co which are widely used in several medical and industrial applications. The results demonstrated that mass attenuation coefficients of the composites at different photon energies are proportional to the filler loading. The validation of FLUKA and GEANT4 Monte Carlo software has been performed in the simulation of transmission experiments as well as WinXCOM software. The tests of the Pb (20%) micro composite for the nuclear radiation shielding reveal that it has high attenuation coefficients for photon radiation.

Different types of photon shielding parameters such as total mass attenuation coefficient (μ/ρ), linear attenuation coefficients (μ), half value layers (HVL), mean free paths (MFP), effective atomic numbers (ZEff), energy absorption build-up factors (EABF), exposure build-up factors (EBF) and kerma relative to air were investigated for the fabricated Cu–Ag based alloys. The considered parameters were measured through gamma spectrometer equipped with HPGe detector in order to obtain the experimental attenuation coefficients and other related parameters at various photon energy in the energy range 59.5–1332.5 keV. The measured μ/ρ values were confirmed with WinXCOM database results. FLUKA and GEANT4 simulation codes were used to examine the compatibility of the experimental and WinXCOM database results with these simulation codes. The exposure buildup factors of the alloy samples were estimated with help of Geometric Progression fitting formula over photon energy 0.015–15 MeV up to 40 mfp penetration depth. The results revealed that the exhibited effectiveness of Cu0.2Ag0.8 alloys against high energetic photon radiations had a good performance than that of alternative absorbers such conventional concretes, glasses and some alloys. The results of the present survey can be quite useful for possible applications of such materials, especially in nuclear laboratory and reactor core design for preference of effective photon shielding materials.

This work presents a detailed radiation shielding study for polymer composites filled with Boron and Molybdenum additives. The chosen novel polymer composites were produced at different percentages of the additive materials to provide a proper evaluation of their neutron and gamma-ray attenuation abilities. The effect of additive particle size on the shielding characteristics was further investigated. On the gamma-ray side, simulation, theoretical and experimental evaluations were performed in a wide range of photon energies varying from 59.5 keV to 1332.5 keV with help of MC simulations (GEANT4 and FLUKA), WinXCOM code, a High Purity Germanium Detector, respectively. A remarkable consistency was reported between them. On the neutron shielding side, the prepared samples produced with nano and micron particle size additives were additionally examined by providing fast neutron removal cross-section (ΣR) and the simulated neutron transmissions through the prepared samples. The samples filled with nano sized particles show better shielding capability than the one filled with micron sized particles. In other words, a new polymer shielding material that does not contain toxic content is introduced: the sample codded N–B0Mo50 exhibits superior radiation attenuation.

Shielding capacities of gamma and neutron radiations of concrete samples with bronze addition and boron carbide at different rates were investigated within the scope of this study. In order to examine the gamma radiation shielding capacities of the produced bronze doped concrete samples, linear attenuation coefficients mass attenuation coefficients, half thickness values layer, one-tenth thickness values layer, effective atomic number and radiation protection efficiency parameters were analyzed using experimental, theoretical (WinXCOM) and simulation (GEANT4 and FLUKA) codes. The gamma radiation shielding capacities of the produced concrete samples were investigated at different energies ranging from 59.5 to 1332.5 keV. The results showed that increasing the amount of bronze in the produced sample attenuated more amount of gamma comparing to the samples that had less bronze. The best sample among the produced concretes was found to be the sample that doped with 50% bronze. Then, different proportions of boron carbide (B4C) were substituted into the sample content (50% bronze) to produce a new concrete doped with bronze and B4C. The neutron shielding abilities of the new concrete samples produced in this way were investigated with the GEANT4 and FLUKA simulation codes. Using different thicknesses and energies the neutron shielding property of the samples was analyzed to test neutron transmission. The results showed that the sample doped with 20% boron carbide was the best attenuator against neutron radiation.

The usage of composites as the shielding materials are highly recommended since they could be used in order to attenuate the undesired radiation with unique properties and advantages in the areas where the radiation is prevalent. In this context, not only are their radiation shielding properties important but also their flexibility, durability and low cost. Due to the mentioned superior characteristics, the polyester based composites are among the most preferred materials. With the aim of creating unique and novel radiation shielding materials, this study investigates gamma and neutron shielding capabilities of the polyester composites reinforced with Boron and Tin nanopowders at different proportions (0–50%, 10–40%, 20–30%, 30-20% and 40-10%, 50-0%). The gamma shielding abilities of the prepared polyester composite materials were evaluated using an HPGe detector system, WinXCOM computer program and different simulation tools (FLUKA and GEANT4) at the energies varying from 59.5 to 1332.5 keV. The experimental, theoretical and simulation results showed remarkable agreement between each other, and the addition of Sn enhances the gamma attenuation performance of the chosen polyester composite materials. In addition to gamma analysis results, neutron shielding properties of the proposed composites are further determined. On this purpose, the transmitted neutron numbers through the samples (as functions of neutron energy and the sample thickness) and effective neutron removal cross sections were evaluated. The neutron shielding performance of the samples showed that the prepared composites could be alternative materials to the existing neutron shields in the literature.

The shielding efficiencies of gamma and neutron radiations for ternary composites containing polyester resin, polyacrylonitrile and gadolinium (III) sulfate at different ratios were investigated in the present study. In order to investigate the gamma radiation shielding capacity of the produced ternary composites, linear and mass attenuation coefficients, half value layer, effective atomic number and radiation protection efficiency parameters were determined experimentally, theoretically and using the GEANT4 simulation code. The gamma shielding capabilities of the composites were studied in the photon energy range of 59.5-1332.5 keV. In order to investigate the neutron shielding abilities of composites, inelastic, elastic, capture and transport numbers, total macroscopic cross section and mean free path parameters were determined with the help of GEANT4 simulation code. In addition, the number of transmitted neutrons at different sample thicknesses and neutron energies were also determined. It was observed that gamma radiation shielding properties were improved due to the increasing amount of gadolinium (III) sulfate and neutron shielding properties were improved due to the increasing amount of polyacrylonitrile. While the composite coded P0Gd50 exhibits a better gamma radiation shielding ability than the others, the neutron shielding of the sample coded P50Gd0 is also more favorable than the others.

This study presents gamma-shielding characteristics of Li2WO4 doped polyester composites. In the study, unsaturated polyester was chosen as resin, Li2WO4 was chosen as filling material, cobalt octoate 6% (CO-6) and methyl ethyl ketone peroxide (MEKP) were respectively chosen as accelerator and initiators. Four different samples with 5%, 10%, 15% and 20% Li2WO4 were prepared and the prepared samples were tested by using 22Na, 54Mn, 57Co, 60Co, 133Ba, 137Cs, 152Eu and 241Am radioactive point-isotropic sources and one gamma spectrometer system based HPGe detector. The experimental results were obtained with the help of the transmission geometry between 59.5 and 1408.0 keV photon energies. For the validation of the results, the test results were compared with the results obtained by WinXCOM computer program and both results showed good agreement. It was observed that the mass attenuation coefficients lie within the range of 0.3042–0.0558 cm2 g-1 for Li2WO4 (5%), 0.4074–0.0556 cm2 g-1 for Li2WO4 (10%), 0.5042–0.0555 cm2 g-1 for Li2WO4 (15%) and 0.5909–0.0553 cm2 g-1 for Li2WO4 (20%) in the energy range of 59.5–1408.0 keV. Comparing to the other Li2WO4 (5%, 10%, 15%) contents, Li2WO4 (20%) was found to have the higher radiation shielding property. This shows that the radiation protection performance of unsaturated polyester increases when Li2W04 is added as filler.

Ferrites are ceramic oxide materials consisting of mainly iron oxide and they have become massively important materials commercially and technologically, having a multitude of uses and applications. The protection against neutron-gamma mixed radiation is crucial in several nuclear applications. From this standpoint, mass attenuation coefficient, radiation protection efficiency and transmission factor of some ferrites namely barium, strontium, manganese, copper and cadmium ferrite has been computed using Geant4 and FLUKA simulations. Based on the simulated mass attenuation coefficient, other significant parameters such as linear attenuation coefficient, effective atomic and electron number, conductivity, half value layer, and mean free path were calculated for the selected ferrite materials. The validation of Monte Carlo geometry has been provided by comparing the mass attenuation coefficient results with standard WinXCom data. Gamma ray exposure buildup factors were computed using geometric progression fitting formula for the chosen ferrites in the energy range 0.015-15 MeV at penetration depths up to 40 mfp. The findings of the present work reveal that among the studied ferrites, barium ferrite and copper ferrite possess superior gamma ray and fast neutron attenuation capability, respectively. The present work provides a comprehensive investigation of the selected iron oxides in the field of neutron and gamma ray.

Polyester is strong and durable material and tends to retain its shape, thus polyester composites have become highly preferred option in high-tech applications. This motivates the usage of polyester composites in the production of radiation shielding materials as well. In present study, gamma ray shielding properties of polyester composite reinforced with different proportions of Cadmium Telluride (5%, 10%, 15% and 20%) have been investigated theoretically and experimentally. The experiments were performed with the use of HPGe detector in a wide range of photon energies varying from 59.5 to 1408.0 keV while XCOM computer program was computed in the same photon energy range to obtain theoretical results and to verify the experimental outcomes. Remarkable radiation protection efficiency was obtained with additive material of Cadmium Telluride, and the radiation protection efficiency was found to be increased with the increase of additive material amount. Negligible discrepancies between experimental and theoretical results were also observed.

In this study, CdS doped polyester composites were produced at different weight ratios, and the impact of dopant amount on gamma and neutron shielding characteristics of a new composite material were further evaluated: the composite matrix was doped at 5%, 10%, 15% and 20% CdS weight ratios of the prepared composite. Then, the produced polyester materials have been characterized using a scanning electron microscope (SEM) and X-ray diffraction (XRD) patterns. Following the structure characterization, the prepared composites were tested using one gamma spectrometer system based HPGe detector with help of 22Na, 54Mn, 57Co, 60Co, 133Ba, 137Cs, 152Eu and 241Am radioactive point-isotropic sources in order to perform the evaluation in a wide energy range of gamma. The obtained results were compared to the results of Geant4 and WinXCOM simulation codes. On the last step of the presented work, the neutron removal cross sections of produced polyester composites were calculated using partial density of elements and their cross sections, and then, neutron shielding characteristics of the prepared samples were determined with help of Geant4 simulation toolkit. Both tested and simulated results of gamma shielding evaluation showed good agreement, and, for all considered photon energies, mass attenuation coefficient (μ/ρ) values of CdS (20%) were always found to be greater than the μ/ρ values of other samples (5%, 10%, 15%). The results for neutron shielding showed that neutron transmission was decreasing with the increase of CdS in the material. In short, having higher μ/ρ values and lower neutron transmission shows that increasing the amount of CdS in the sample causes the higher radiation shielding property for both gamma and neutron.

Hamamatsu single anode R7761 and multi-anode R5900-00-M16 Photomultiplier Tubes have been characterized for use in a Secondary Emission (SE) Ionization Calorimetry study. SE Ionization Calorimetry is a novel technique to measure electromagnetic shower particles in extreme radiation environments. The different operation modes used in these tests were developed by modifying the conventional PMT bias circuit. These modifications were simple changes to the arrangement of the voltage dividers of the baseboard circuits. The PMTs with modified bases, referred to as operating in SE mode, are used as an SE detector module in an SE calorimeter prototype, and placed between absorber materials (Fe, Cu, Pb, W, etc.). Here, the technical design of different operation modes, as well as the characterization measurements of both SE modes and the conventional PMT mode are reported.

Prediction of $Z\rightarrow l^{+}l^{-}$ production cross section (where $l^{\pm} =e^{\pm},\mu^{\pm}$) in proton-proton collisions at $\sqrt{s}$=14 TeV is estimated up to next-to-next-to-leading order (NNLO) in perturbative QCD including next-to-leading order (NLO) electroweak (EW) corrections. The total inclusive Z boson production cross section times leptonic branching ratio, within the invariant mass window $66<m_{ll}<116$ GeV, is predicted using NNLO HERAPDF2.0 at NNLO QCD and NLO EW as $\sigma_{Z}^{Tot}$= 2111.69$_{-26.92}^{+26.31}$ (PDF) $\pm11$ ($\alpha_{s}$) $\pm$17 (scale) $^{+57.41}_{-30.98}$ (parameterization and model). Theoretical prediction of the fiducial cross section is further computed with the latest modern PDF models (CT14, MMHT2014, NNPDF3.0, HERAPDF2.0 and ABM12) at NNLO for QCD and NLO for EW. The central values of the predictions are based on DYNNLO 1.5 program and the uncertainties are extracted using FEWZ 3.1 program. In addition, the cross section is also calculated as functions of $\mu_{R}$ and $\mu_{F}$ scales. The choice of $\mu_{R}$ and $\mu_{F}$ for scale variation uncertainty is further discussed in details.

Predictions of fiducial cross sections, differential cross sections and lepton charge asymmetry are presented for the production of $W^{\pm}$ bosons with leptonic decay up to next-to-next-to-leading order (NNLO) in perturbative QCD. Differential cross sections of $W^{\pm}$ bosons and W boson lepton charge asymmetry are computed as a function of lepton pseudorapidity for a defined fiducial region in $pp$ collisions at $\sqrt{s}=13$ TeV. Numerical results of fiducial $W^{\pm}$ cross section predictions are presented with the latest modern PDF models at next-to-leading order (NLO) and NNLO. It is found that the CT14 and NNPDF 3.0 predictions with NNLO QCD corrections are about 4$\%$ higher than the NLO CT14 and NNPDF 3.0 predictions while MMHT 2014 predictions with NLO QCD corrections are smaller than its NNLO QCD predictions by approximately 6$\%$. In addition, the NNLO QCD corrections reduce the scale variation uncertainty on the cross section by a factor of 3.5. The prediction of central values and considered uncertainties are obtained using FEWZ 3.1 program.

The MIP Timing Detector will provide additional timing capabilities for detection of minimum ionizing particles (MIPs) at CMS during the High Luminosity LHC era, improving event reconstruction and pileup rejection. The central portion of the detector, the Barrel Timing Layer (BTL), will be instrumented with LYSO:Ce crystals and Silicon Photomultipliers (SiPMs) providing a time resolution of about 30 ps at the beginning of operation, and degrading to 50-60 ps at the end of the detector lifetime as a result of radiation damage. In this work, we present the results obtained using a 120 GeV proton beam at the Fermilab Test Beam Facility to measure the time resolution of unirradiated sensors. A proof-of-concept of the sensor layout proposed for the barrel region of the MTD, consisting of elongated crystal bars with dimensions of about 3 x 3 x 57 mm$^3$ and with double-ended SiPM readout, is demonstrated. This design provides a robust time measurement independent of the impact point of the MIP along the crystal bar. We tested LYSO:Ce bars of different thickness (2, 3, 4 mm) with a geometry close to the reference design and coupled to SiPMs manufactured by Hamamatsu and Fondazione Bruno Kessler. The various aspects influencing the timing performance such as the crystal thickness, properties of the SiPMs (e.g. photon detection efficiency), and impact angle of the MIP are studied. A time resolution of about 28 ps is measured for MIPs crossing a 3 mm thick crystal bar, corresponding to an MPV energy deposition of 2.6 MeV, and of 22 ps for the 4.2 MeV MPV energy deposition expected in the BTL, matching the detector performance target for unirradiated devices.

In the last few decades, the challenges of ionizing radiationIonizing radiation shieldingRadiation shielding have begun gaining attention of investigators in order to minimize the harmful effectsHarmful effects of various radiations especially on workers who are interested in the outcome of a nuclearNuclear or radiologicalRadiological situation that requires protectionProtection. In this context, the presented chapter focuses on the shieldingShielding preparation, materials designMaterials design, photonPhoton, and neutron shieldingNeutron shielding performancesPerformance of polymer-based compositesPolymer-based composite doped with bismuth nitrateBismuth nitrate in different weight ratiosWeight ratio. Here, the photon attenuationPhoton attenuation behavior of the prepared compositesComposite is determined using a gamma spectrometerGamma spectrometer equipped with High Purity Germanium (HPGe) detectorHPGe detector that covers a wide energyEnergy range varying from 0.060 to 1.408 meV. Besides, the obtained experimental dataExperimental data are further compared with the results of theoreticalTheoretical (WinXCOM softwareWinXCOM software) and Monte Carlo simulation (GEANT4)Monte Carlo simulation (GEANT4). In addition, the fast neutronFast neutron massMass removal cross sectionsCross section and the numbers of transmitted neutronsNeutron at different thicknessThickness and neutronNeutron energiesEnergy are estimated with the use of GEANT4Monte Carlo simulation (GEANT4) simulationsSimulation by codingCoding the elemental compositions of the fabricated compositesComposite. The results showed that the gamma attenuationGamma attenuation was improved with the increase of BiNOBiNO dopantDopant amount. Among the prepared samples, the sample with 20% BiNOBiNO concentrationConcentration was found to be the best radiation shieldingRadiation shielding material. In addition to being used for the ionizing radiationIonizing radiation shieldingRadiation shielding, such polyesterPolyester compositesComposite can also be used as shielding absorbersShielding absorber for the low-energyLow-energy ionizing radiationIonizing radiation. In short, it is expected that the researchers and scientists in the fieldsField of nuclearNuclear and medical physicsMedical physics will benefit from this chapter.

Inclusive W ([Formula: see text]) boson QCD predictions and lepton charge asymmetry in proton–proton collisions at [Formula: see text] = 14 TeV is performed in this study. Total and fiducial cross section predictions are obtained up to next to next to leading order (NNLO) QCD corrections using Monte Carlo for FeMtobarn processes (MCFM) MC generator. To validate the predictions, a detailed comparison of NNLO QCD calculations with 8 TeV CMS results is performed. To discuss the advantage of the higher order QCD predictions on the scale uncertainty, a scale dependence study is presented based on the choice of renormalization (μ R ) and factorization (μ F ) scale variations. W boson – lepton charge asymmetry and differential cross section as a function of lepton pseudorapidity at [Formula: see text] = 14 TeV are further performed in 11 |η| regions.

The CMS detector at the CERN Large Hadron Collider features as its innermost component a silicon pixel detector. The original pixel detector was completely replaced during the 2016-2017 winter technical stop. One of the goals of this Phase-1 Upgrade of the pixel detector was to replace the sensors in the original CMS forward pixel detector with new, unirradiated sensors. The new CMS forward pixel detector must survive an integrated luminosity of 300 fb$^{-1}$ before being replaced again prior to the High-Luminosity LHC era. Just as in the original construction, the Phase-1 forward pixel sensors were made of n$^{+}$-in-n Diffusion Oxygenated Float Zone silicon. This note documents the quality spot-checking of the new sensors, comparing our results with those provided by the vendor. In general there was good agreement between the results.

Hamamatsu single anode R7761 and multi-anode R5900-00-M16 Photomultiplier Tubes have been characterized for use in Secondary Emission Ionization Calorimetry study, that is a novel techique to measure the electromagnetic shower particles in extreme radiation environment. There are different SE modes used in the tests, developed from conventional PMT mode. Here, the technical design of secondary emission modules and characterization measurements of both SE modes and the PMT mode are reported.

Cross section predictions of W and Z bosons in association with jets (up to 6 jets, $W\to\ell^{\pm}\nu$ and $Z\to\ell^{\pm}$ where $\ell^{\pm}$=$e^{\pm}$ or $\mu^{\pm}$) in proton-proton collisions at $\sqrt{s}$=14 TeV is performed using Alpgen MC generator with CTEQ6L1 leading order parton distribution function. In addition, W and Z boson cross sections are obtained up to next to next to leading order (NNLO) QCD corrections using MCFM MC generator. To validate the predictions, a detailed comparison of NNLO QCD calculations with 8 TeV CMS results for total cross section is performed and a fiducial region is further defined to make a comparison of predictions with 7 TeV and 13 TeV ATLAS results.

The proton-proton collision energy at Large Hadron Collider (LHC) has been 7, 8 and 13 TeV recently with the goal of reaching to 14 TeV which is the maximum capacity of the LHC. However, there is still more physics yet to be explored and tested beyond the energy regime of the LHC to reach new discoveries. Therefore, a new collider bigger than the LHC machine, which will be able to collide protons at 100 TeV center-of-mass energy, is under consideration by the high-energy physics community. To provide an insight to the transition from LHC to 100 TeV collider, some properties of W and Z processes are investigated in a range of collision energy from 7 to 100 TeV using HERAPDF2.0, MMHT2014, NNPDF3.1 and CT14 NNLO PDF models at NNLO QCD. The considered properties are the production rates of W and Z bosons, the change of uncertainties (PDF, renormalization and factorization scales, strong coupling constant, model and parameterization), W boson lepton charge asymmetry, forward-backward asymmetry, and k-Factors of W and Z bosons.

The proton-proton collision energy at Large Hadron Collider (LHC) has been 7, 8 and 13 TeV recently with the goal of reaching to 14 TeV which is the maximum capacity of the LHC. However, there is still more physics yet to be explored and tested beyond the energy regime of the LHC to reach new discoveries. Therefore, a new collider bigger than the LHC machine, which will be able to collide protons at 100 TeV center-of-mass energy, is under consideration by the high-energy physics community. To provide an insight to the transition from LHC to 100 TeV collider, some properties of W processes are investigated in a range of collision energy from 7 to 100 TeV using HERAPDF2.0, MMHT2014, NNPDF3.1 and CT14 NNLO PDF models at NNLO QCD. The considered properties are the production rates of W, the change of uncertainties (PDF, renormalization and factorization scales, strong coupling constant, model and parameterization), and W boson lepton charge asymmetry.

The proton-proton collision energy at Large Hadron Collider (LHC) has been 7, 8 and 13 TeV recently with the goal of reaching to 14 TeV which is the maximum capacity of the LHC. However, there is still more physics yet to be explored and tested beyond the energy regime of the LHC to reach new discoveries. Therefore, a new collider bigger than the LHC machine, which will be able to collide protons at 100 TeV center-of-mass energy, is under consideration by the high-energy physics community. To provide an insight to the transition from LHC to 100 TeV collider, some properties of W processes are investigated in a range of collision energy from 7 to 100 TeV using HERAPDF2.0, MMHT2014, NNPDF3.1 and CT14 NNLO PDF models at NNLO QCD. The considered properties are the production rates of W, the change of uncertainties (PDF, renormalization and factorization scales, strong coupling constant, model and parameterization), and W boson lepton charge asymmetry.

Cross section predictions of W and Z bosons in association with jets (up to 6 jets, $W\to\ell^{\pm}ν$ and $Z\to\ell^{\pm}$ where $\ell^{\pm}$=$e^{\pm}$ or $μ^{\pm}$) in proton-proton collisions at $\sqrt{s}$=14 TeV is performed using Alpgen MC generator with CTEQ6L1 leading order parton distribution function. In addition, W and Z boson cross sections are obtained up to next to next to leading order (NNLO) QCD corrections using MCFM MC generator. To validate the predictions, a detailed comparison of NNLO QCD calculations with 8 TeV CMS results for total cross section is performed and a fiducial region is further defined to make a comparison of predictions with 7 TeV and 13 TeV ATLAS results.

Electromagnetic calorimetry in high-radiation environments, e.g., forward regions of lepton and hadron collider detectors, is quite challenging. Although total absorption crystal calorimeters have superior performance as electromagnetic calorimeters, the availability and the cost of the radiation-hard crystals are the limiting factors as radiation-tolerant implementations. Sampling calorimeters utilizing silicon sensors as the active media are also favorable in terms of performance but are challenged by high-radiation environments. In order to provide a solution for such implementations, we developed a radiation-hard, fast and cost-effective technique, secondary emission calorimetry, and tested prototype secondary emission sensors in test beams. In a secondary emission detector module, secondary emission electrons are generated from a cathode when charged hadron or electromagnetic shower particles penetrate the secondary emission sampling module placed between absorber materials. The generated secondary emission electrons are then multiplied in a similar way as the photoelectrons in photomultiplier tubes. Here, we report on the principles of secondary emission calorimetry and the results from the beam tests performed at Fermilab Test Beam Facility as well as the Monte Carlo simulations of projected, large-scale secondary emission electromagnetic calorimeters.

Bu çalışma, Büyük Hadron Çarpıştırıcısı (BHÇ) ve Gelecekteki Dairesel Çarpıştırıcı (FCC) için 14, 27 ve 100 TeV kütle merkez enerjilerinde Wbb ̅ üretim kanalının leading order (LO) ve next-to-leading order (NLO) kuantum renk dinamiği (QCD) tesir kesitlerini sunmaktadır. Sayısal sonuçları elde etmek için beş farklı parton dağıtım fonksiyonu (PDF) kullanılmış ve PDF hataları MCFM Monte Carlo programı ile elde edilmiştir. Ayrıca renormalizasyon ve faktörizasyon ölçeklerinin farklı değerleri için scale hata payı hesaplaması yapılmıştır. W üretim kanalında elde edilen scale hata paylarının aksine Wbb ̅ üretim kanalında NLO QCD'deki scale hata payları LO QCD’deki scale hata paylarından daha yüksek bulunmuştur. Artan enerjinin hata payları üzerindeki etkisini test etmek için, artan enerji ile scale, PDF ve α_S belirsizliklerinin karşılaştırılması yapılmıştır. Ayrıca, bu çalışmada kullanılan simülasyon kodunun doğruluğunu onaylamak için √s=7 TeV enerji değerinde elde edilen sonuçlar ile aynı enerjideki CMS verileri karşılaştırılmıştır. Yazılmış olan kodların doğruluğunun onaylanmasından sonra, Wbb ̅ üretim kanalının √s= 14, 27 ve 100 TeV'deki LO ve NLO QCD tesir kesitleri hesaplanmıştır. Daha sonra √s= 7 TeV enerjisindeki veri ile aynı istatistiğe sahip verinin elde edilmesi için √s= 14, 27 ve 100 TeV enerjilerinde ihtiyaç duyulan veri miktarı hesaplanmıştır.

In high-radiation environments, electromagnetic calorimetry is particularly challenging. To address this, a feasible approach involves constructing a sampling calorimeter that employs radiation-hard active media, albeit at the expense of high energy resolution. In response, we developed an innovative technique, secondary emission calorimetry, which offers radiation resistance, rapid response, robustness, and cost-effectiveness. Our efforts involve the creation of prototype secondary emission sensors, subjected to comprehensive testing within test beams. In the secondary emission detector module, incident charged hadrons or electromagnetic shower particles trigger the generation of secondary emission electrons from a cathode. These generated electrons are subsequently amplified in a manner similar to the process within photomultiplier tubes. This report provides an insight into the principles underlying secondary emission calorimetry, presents findings from beam tests, and outlines Monte Carlo simulations that project towards the potential application of large-scale secondary emission electromagnetic calorimeters.

The impact of higher-order matrix elements and [Formula: see text] and [Formula: see text] scales on the NLO K factors for ZZ vector boson pairs in proton–proton collisions are presented in this study. All predictions are performed using MCFM-8.0 Monte Carlo generator. First, the QCD predictions of ZZ production at LO and NLO accuracies are obtained using two most recent PDFs, MMHT2014 and CT14. To discuss the impact of higher-order matrix elements on the NLO K factors, both LO and NLO corrections are obtained by LO, NLO and NNLO matrix elements of these two most recent PDFs. Then, the impact of [Formula: see text] and [Formula: see text] scales on the NLO K factors are further discussed by using six different values of [Formula: see text] and [Formula: see text] in a range of [Formula: see text], [Formula: see text], where [Formula: see text] is Z boson mass.

In this paper, fiducial cross-sections of lepton pairs with opposite charge via Z → l+ l- (l± = μ±, e±) are calculated at a center-of-mass energy of 14 TeV by applying different transverse momentum selections to evaluate their impact on the production cross-section as well as the differential cross-section of Z bosons in terms of lepton pseudorapidity. The predictions are computed by next-to-next-to-leading order quantum chromodynamics including next-to-leading order electroweak corrections. Forward-backward asymmetry prediction for the Drell?Yan production in proton-proton collision is further calculated at 14 TeV using HERAPDF2.0, MMHT2014, NNPDF3.1, and CT14 parton distribution function models. Then 14 TeV QCD predictions of forward-backward asymmetry are presented as a function of dilepton mass for four different Z boson rapidity regions.

QCD predictions of the Z (Z → l+l) boson in association with jets (up to 2 jets) in proton?proton collisions are presented in this study. The results are predicted at LO and NLO accuracy using two most recent parton distribution functions, CT14 and MMHT2014. LO and NLO corrections are obtained with LO, NLO, and NNLO PDFs to find out the best PDF, which provides well compatible predictions with the experimental measurements. QCD predictions are performed at 13 and 14 TeV center-of-mass energies. To verify the obtained results, the predictions are compared with the measured results by ATLAS collaboration. NLO QCD predictions obtained by using NLO and NNLO PDFs show good agreement with the experimental data. The comparison of NLO predictions at 13 and 14 TeV center-of-mass energies shows that the Large Hadron Collider will provide approximately 9% more yield at 14 TeV center-of-mass energy than the yield at 13 TeV center-of-mass energy for the Z boson in association with 1 and 2 jets.

The Large Hadron Collider (LHC) at CERN has been designed to collide beams of protons at 7, 8, 13, and 14 TeV center-of-mass energies and a new hadron collider called the Future Circular Collider (FCC), which is larger and more energetic than the LHC, is being planned for the near future. The maximum planned energy for FCC is 100 TeV center-of-mass energy. In this regard, we present the leading order and next-to-leading order cross-section predictions of two simultaneously produced opposite-sign W bosons at 7, 8, 13, 14, and 100 TeV center-of-mass energies by using the MCFM MC generator. The results are obtained by CT14, MMHT2014, and MSTW2008 parton distribution functions. Finally, the advantage of increasing collision energy at hadron colliders is discussed by comparing the amount of data recorded at different center-of-mass energies for the pp → W+W- process.