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Öğe Towards a muon collider (vol 83, 864, 2023)(Springer, 2024) Accettura, Carlotta; Adams, Dean; Agarwal, Rohit; Ahdida, Claudia; Aime, Chiara; Amapane, Nicola; Amorim, David; Denizli, HalukÖğe Towards a muon collider(Springer, 2023) Accettura, Carlotta; Adams, Dean; Agarwal, Rohit; Ahdida, Claudia; Aime, Chiara; Amapane, Nicola; Amorim, David; Denizli, HalukA muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by the recently-formed International Muon Collider Collaboration. This Review summarises the status and the recent advances on muon colliders design, physics and detector studies. The aim is to provide a global perspective of the field and to outline directions for future work.Öğe Evolution of fundamental mechanical properties with aliovalent Co/Cu partial substitution and preparation method for Y-123 system(Springer, 2024) Öztürk, O.; Safran, S.; Bulut, F.; Seydioğlu, T.; Akkurt, Bahadır; Terzioğlu, Cabir; Yıldırım, GürcanThis study investigates the effect of aliovalent Co/Cu replacement and preparation method on fundamental mechanical performance features of YBa2Cu3-xCoxO7-delta (Y-123) ceramic system depending on the crack propagation mechanism by Vickers hardness measurements (H-v) and mechanical investigation models for the first time. All the findings are verified by the scanning electron microscopy (SEM) examinations. Besides, the electron-dispersive X-ray (EDX) technique verifies the successful substitution mechanism. Besides, the Vickers hardness parameters improve systematically with the increment in the Co/Cu partial substitution (serving as a barrier) level due to formation of operable slip systems, ionic bond formations, and decrement of stress-amplified strain fields. Moreover, the Y-123 ceramic produced by solid-state reaction method and molecular weight of 0.20% presents the densest and smoothest surface morphology with the largest particle distributions and well-linked cobblestone-like grains. On the other hand, the Y-123 ceramic compounds produced by the sol-gel method are more sensitive and responsive to the indentation test loads. All the findings are wholly supported by the mechanical performance properties, including the shear modulus, resilience, and degree of granularity. Furthermore, the mechanical models indicate that every compound prepared exhibits the untypical reverse indentation size effect (RISE). Additionally, the modeling studies display that the induced cracking (IIC) approach is found to be the most appropriate method to examine true Vickers hardness parameters in the plateau limit regions. All in all, this comprehensive study reports efficiently exploiting the process-structure-property relationships in Y-123 ceramic material design for physical science and mechanical application fields using the aliovalent partial substitution and preparation condition.Öğe Characterization of Sm0.3Ce0.2Sr0.5MnO3 as an electron-doped system: Structural, electrical, and dielectric properties(Springer, 2024) Koç, Nevin Soylu; Gökçen, Muharrem; Varilci, Ahmet; Altıntaş, Sevgi PolatA novel samarium-based cerium-doped ceramic manganite of Sm0.3Ce0.2Sr0.5MnO3 (SCSMO) was prepared via the high-temperature solid-state reaction method. The experimental investigation focused on exploring the crystallographic, morphological, and dielectric characteristics of the perovskite ceramic. Rietveld's refinements of X-ray diffraction patterns confirm that a single-phase orthorhombic crystal structure with the space group of Pnma (62) without any detectable impurity phase is obtained for ceramic perovskite. Based on X-ray data, the average size of crystallites was determined to be 80.9 nm using the Williamson-Hall method. The surface morphology analysis through scanning electron microscopy (SEM) revealed distinct grains with an average size of 8.22 mu m. The study utilized dielectric and impedance spectroscopy at different temperatures and frequencies to thoroughly examine the electrical parameters of SCSMO. Through this analysis, a relationship between the conduction mechanism and structural qualities was established.Öğe Probing the electromagnetic properties of the neutrinos at future lepton colliders(Elsevier, 2024) Denizli, Haluk; Şenol, Abdulkadir; Köksal, MuratIn this study, we explore the non-standard v (v) over bar gamma gamma couplings parametrized by dimension-seven operators via e(+)e(-) -> v (v) over bar gamma process at the FCC-ee/CEPC and mu(+)mu(-) -> v (v) over bar gamma process at the Muon Colliders. For the detailed Monte Carlo simulation, all signal and relevant background events are produced within the framework of Madgraph where non-standard v (v) over bar gamma gamma couplings are implemented. After passing through Pythia for parton showering and hadronization, detector effects are included via tuned corresponding detector cards for each collider in Delphes. Projected sensitivities on v (v) over bar gamma gamma couplings are obtained at a 5% confidence level without and with 5% systematic uncertainties for the FCC-ee/CEPC and the Muon Colliders, showcasing the complementarity between lepton colliders. Our best limit on the anomalous v (v) over bar gamma gamma couplings even with 5% systematic uncertainties for muon collider with root s = 10 TeV and L-int = 10 ab(-1) are found to be fourteen orders of magnitude stronger than the upper bound obtained from rare decay Z -> gamma gamma v (v) over bar analysis using LEP data.Öğe Performance of styrene polymerized plastic scintillator with micropixel avalanche photodiode(Pergamon-Elsevier Science Ltd, 2024) Sadigov, Azer; Berikov, Daniyar; Nuruyev, Sabuhi; Akbarov, Ramil; Yılmaz, Ercan; Ahmadov, FaigThis paper presents the performance of polystrene based plastic scintillator produced in Turkish Energy, Nuclear and Mineral Research Agency (TENMAK). The scintillator is manufactured using thermal polymerization of commercially available styrene monomer doped with first and second fluorescent dyes. The absorption spectrum of the scintillator exhibited two absorption bands at 225 nm and 340 nm, with an absorption edge observed at 410 nm. The wavelength of the emitted light was measured in the range of 400-800 nm, with a maximum intensity at 427 nm. Internal conversion electrons from the 137Cs source were used to evaluate the characteristics of the new scintillator, particularly its light yield. As the light readout the MAPD-3NM type silicon photomultiplier array (4 x 4) with an active area of 15 x 15 mm2, assembled using single MAPDs with an active area of 3.7 x 3.7 mm2, was used. The light yield of the scintillator was determined to be 6134 photons/MeV. In addition, the efficiency of the scintillator for gamma rays with an energy of 662 keV was found out to be approximately 1.8%. CmBe neutron source was employed to evaluate its fast neutron detection performance. However, neutron/gamma discrimination using pulse shape discrimination (charge integration) method was not observed. The results demonstrate the potential of produced plastic scintillator for various applications, particularly in radiation monitoring and detection systems.Öğe Ultrahigh-responsivity ultraviolet photodetectors based on AlGaN/GaN double-channel high-electron-mobility transistors(American Chemical Society, 2023) Wang, Haodong; Feng, Meixin; Zhong, Yaozong; Chen, Xin; Gao, Hongwei; Yılmaz, Ercan; Sun, QianIn this work, high-performance ultraviolet (UV) photodetectors (PDs) based on an AlGaN/GaN double-channel high-electron-mobility transistor (HEMT) were fabricated and investigated using 360 nm illumination. The design of the novel device structure introduces double two-dimensional electron gas channels, which remarkably improve the effectiveness in the collection of photo generated carriers and make it work as a two-terminal normally off device. The device exhibited a high responsivity of 2.1 x 10(7) A/W and a high specific detectivity of 1.7 x 10(15) Jones under the illumination of 9.7 mu W/cm(2), indicating the excellent capability of detecting an ultraweak signal. Meanwhile, a distinguished transient performance was also observed when it operated under 500 Hz pulse illumination. Combining fabrication conciseness and outstanding performance advantages, the proposed AlGaN/GaN double-channel HEMT UV PD shows promising potential in the development of next-generation UV PDs.Öğe Updates and improvements of Turkish Plants Data Service (TüBİVES)(2011) Bakış, Yasin; Babaç, Mehmet Tekin; Uslu, EmelReaching biological information of the studied taxa became quite simple by introducing biodiversity information databases through internet. TüBİVES (Turkish Plants Data Service) is the first and the most efficient biodiversity database of the plants in Turkey. In this study, the structural of TüBİVES has been changed according to needs in new data types such as, chromosomal numbers, vernacular names, uses of plants, IUCN categories for endemics, nomenclature and synonym information of plants distributed in Turkey. The structure of database and querying algorithm have been updated both for TüRKNOM (Nomenclatural Database of Turkish Vascular Plants) and TüBİVES. © 2011 IEEE.Öğe Investigation of annealing temperature and gamma irradiation on HfO2/Dy2O3/Al2O3/n-Si (100) memory capacitor(Institute of Electrical and Electronics Engineers Inc., 2023) Chirwa, Racheal; Mutale, Alex; Yılmaz, ErcanThe effect of annealing temperature and gamma irradiation on Al/HfO2/Dy2O3/Al2O3/n-Si (100) tri-layer capacitors have been studied intensively. The HfO2/Dy2O3/Al2O3 were fabricated by using both RF magnetron sputtering and E-beam evaporation techniques, respectively. The samples were annealed at 300oC, 500oC,700oC, and 900oC in N2 ambient for 40min. The device annealed at 700oC had a large memory window of 8.22V under sweeping voltage ±12V compared to other annealed devices. This is attributed to the excellent charge storage capability of the device. Thereafter, this device was exposed to gamma irradiation at various doses of 4 Gy to 16 Gy. C-V and Gm/-V measurements were performed before and after irradiation at 1MHz. The C-V curves shifted toward the positive voltage side. This could be related to the oxide-trapped and interface-trapped charges generated during irradiation © 2023 IEEE.Öğe Radiation hard monolithic CMOS sensors with small electrodes for HL-LHC and beyond(Sissa Medialab Srl, 2021) Sanchez, C. Solans; Allport, Phil; Tortajada, Ignacio Asensi; Bortoletto, Daniela; Buttar, Craig; Denizli, Haluk; Oyulmaz, Kaan YükselThe upgrade of tracking detectors for experiments at the HL-LHC and future colliders requires the development of novel radiation hard silicon sensors. We target the replacement of hybrid pixel detectors with Depleted Monolithic Active Pixel Sensors (DMAPS) that are radiation hard monolithic CMOS sensors. We designed, manufactured and tested DMAPS in the TowerJazz 180 nm CMOS imaging technology with small electrodes pixel designs, that have a pixel pitch well below the current hybrid pixel detectors, and less multiple scattering due to a reduced total silicon thickness. In this document we present the recent results from these sensors manufactured on Czochralski silicon substrates in terms of cluster size, impact on tracking and time resolution from measurements carried out at beam tests on irradiated samples at 1e15 1 MeV neq/cm2,. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0).Öğe SPICE modeling of RADFETs with different gate oxide thicknesses(Institute of Electrical and Electronics Engineers Inc., 2023) Marjanovic, M.; Gürer, Umutcan; Mitrovic, N.; Yılmaz, Ozan; Dankovic, D.; Budak, Erhan; Yılmaz, ErcanThis paper will present guidelines for creating a SPICE model of RADFETs with different gate oxide thicknesses. Model parameters, such as threshold voltage and carrier mobility, were extracted from the transfer characteristics in the saturation region. The model was satisfactorily used to simulate RADFETs with oxide thicknesses ranging from 40 nm to 300 nm. © 2023 IEEE.Öğe Quantum coherence resourced by the strong nuclear quadrupolar interaction(IOP Publishing Ltd, 2023) Çakmak, Selçuk; Gençten, Azmi; Altıntaş, FerdiWe propose a setup for studying the quantum coherence properties of a quadrupolar nucleus using the nuclear magnetic resonance platforms We consider powder samples labeled with 23Na and oriented with respect to the static magnetic field. By using the l 1-norm of coherence, we examine the quantum coherence in the Zeeman basis at thermal equilibrium. Non-zero coherence is found to result from the strong nuclear quadrupolar spin interactions. It is also shown that higher coherence is created as the quadrupolar interaction coefficient increases. We also discuss the stability of coherence in a possible measurement process in order to use it as a potential resource in any quantum computation protocol.Öğe Investigation of hybrid wires combining superconductive MgB2 and ultra-conductive Graphene/Cu sheath(Elsevier Science Sa, 2024) Karaboğa, Fırat; Farhangmehr, Mojtaba; Özmen, Ahmet; Yetiş, Hakan; Belenli, İbrahim; Ertuğrul, MehmetIn our study, hybrid wires with ultra-conductive Graphene/Copper(GCu) sheath and superconducting MgB2 core were produced and experimentally examined. Cu tubes with outer/inner diameters of 15/12 mm were first coated with multi-layered graphene by chemical vapour deposition (CVD) method. Then, the ultra-conductive G/ Cu tubes were filled with Mg+ 2B powder and they were gradually drawn into wires with a diameter of 1.94 mm. According the analysis results, the graphene coating process was successfully completed and the hybrid wires were produced by achieving MgB2 superconducting phase formation after annealing at 650 circle C for 1 h. In this study, a graphene-coated copper tube with a CVD process was used for the first time to manufacture a superconducting wire. The ampacity value of industrial G/Cu sample has been improved in hybrid wires about 75% despite Cu exposed to mechanical deformations throughout the wire production process after graphene coating.Öğe Graph-based algorithm for the understanding of failures in the ATLAS infrastructure(IOP Publishing, 2023) Uribe, Gustavo A.; Tortajada, Ignacio Asensi; Sanchez, Carlos Solans; Rummler, Andre; Oyulmaz, Kaan Yüksel; Denizli, HalukThe ATLAS Technical Coordination Expert System is a knowledge-based application which describes and simulates the ATLAS experiment based on its components and their relationships with differing levels of granularity but with an emphasis on general infrastructure. It facilitates the sharing of knowledge and improves the communication among experts with different backgrounds and domains of expertise. The developed software has become essential for the planning of interventions as it gives easily insight into their consequences. Furthermore, it has also proven to be useful for exploring the most effective ways to improve the ATLAS operation and reliability by identifying points of failure with significant impact. The underlying database describes more than 13,000 elements with 89,000 relationships among them. It combines information from diverse domains such as detector control and safety systems, gas and water supplies, cooling, ventilation, cryogenics, and electricity distribution. As the most recent addition, a tool to identify the most probable cause of a failure state has been developed. This paper discusses the graph-based algorithm currently implemented by that tool and shows its behaviour based on the parameters entered by the user. An example in form of a real failure event is given which demonstrates the potential of the Expert System for understanding major failures faster in urgent situations.Öğe Performance improvement of GaN-based microdisk lasers by using a PEALD-SiO2 passivation layer(Optica Publishing Group, 2023) Zhao, Hanru; Feng, Meixin; Liu, Jianxun; Sun, Xiujian; Li, Yongjian; Yılmaz, ErcanDry-etching is often utilized to shape GaN-based materials. However, it inevitably causes plenty of sidewall defects as non-radiative recombination centers and charge traps that deteriorate GaN-based device performance. In this study, the effects of dielectric films deposited by plasma-enhanced atomic layer deposition (PEALD) and plasma-enhanced chemical vapor deposition (PECVD) on GaN-based microdisk laser performance were both investigated. The results demonstrated that the PEALD-SiO2 passivation layer largely reduced the trap-state density and increased the non-radiative recombination lifetime, thus leading to the significantly decreased threshold current, notably enhanced luminescence efficiency and smaller size dependence of GaN-based microdisk lasers as compared with the PECVD-Si3N4 passivation layer.Öğe Annealing-induced modifications on structural, surface chemical bonding, and electrical characteristics of p-NiO/n-TiO2 heterostructure(Springer, 2023) Kaya, Şenol; Soykan, Uğur; Sunkar, Mustafa; Karaboğa, Seda; Doğan, Muhsin Uğur; Terzioğlu, Rıfkı; Yıldırım, Gürcan; Terzioğlu, CabirThe influences of annealing temperatures on the electrical characteristics of a p- NiO/n-TiO2 heterojunction diode were thoroughly investigated, taking into account changes in microstructure, morphology, and surface chemistry of the p-NiO/n-TiO2 films, which were deposited on an insulating SiO2/ Si layer. During different annealing processes, considerable stress variations were observed in the p-NiO/n-TiO2 films due to the crystalline evolution of p-NiO and n-TiO2. Notably, the crystallization of the TiO2 layer, which serves as the intermediary between the back contact materials and NiO, led to the evident formation of grain structures. As the annealing temperature increased, the surface roughness also grew from 5.4 to 8.7 nm. At an annealing temperature of 500 degrees C, the formation of a parasitic NiTiOx phase was observed, particularly at the interface between NiO and TiO2. Conversely, the study also revealed that annealing temperature played a significant role in the rectifying behavior, barrier potential, and ideality factor of the diode. Among the various annealing processes, the most favorable results were achieved after annealing at 400 degrees C. At this temperature, the diode demonstrated the lowest ideality factor of 1.89, accompanied by superior rectifying behavior and a barrier potential of 0.70 eV. The findings clearly indicate that any alterations in the surface chemistry and microstructure of the film directly impact the diode's characteristics. Thus, optimizing the annealing temperature becomes crucial for enhancing the performance of the p-NiO/n-TiO2 heterojunction diode.Öğe Development of modulation, pairing mechanism, and slip system with optimum vanadium substitution at Bi-sites in Bi-2212 ceramic structure(Elsevier Science Sa, 2023) Ülgen, Asaf Tolga; Okur, Semih; Erdem, Ümit; Terzioğlu, Cabir; Yıldırım, Gürcan; Turgay, TahsinPresent study focuses extensively on the change in electrical, superconducting and microhardness parameters with partial substitution of trivalent V+3 impurities replacing Bi+3 ions in Bi-2212 ceramic compound with the aid of dc electrical resistivity and microhardness test measurements. Experimental findings, calculation results, and phenomenological discussions provide that the optimum vanadium substitution level is found to be x = 0.01 in the Bi2.0-xVxSr2.0Ca1.1Cu2.0Oy (Bi-2212) ceramic system for the highest conductivity, crystallinity quality, superconducting, and mechanical performance features depending on the decreased microscopic structural problems. All the findings are wholly verified by scanning electron microscopy (SEM) and X-Ray diffraction (XRD) analyses. The dc electrical measurements indicate that the optimum vanadium ions support the pairing mechanism for the formation of new polaronic states in the clusters of microdomains, and hence expand superconducting energy gap due to the enhancement of amplitude part of pair wave function in the spin-density wave systems. The excess vanadium content degrades all the basic thermodynamics and quantum mechanical quantities mentioned due to the stress-induced phase transformation. Numerically, the Bi-2212 advanced ceramic matrix prepared by the optimum vanadium impurity is noticed to present the smallest residual resistivity value of 0.08 m & omega; cm, room temperature resistivity value of 8.84 m & omega; cm, and broadening degree of 0.36 K. Similarly, the ceramic material is found to possess the highest residual resistivity ratio of 3.05, carrier concen-tration number of 0.153041, critical transition offset and onset value of 84.66 K and 85.02 K, respectively. Besides, the microhardness findings reveal that the same compound with the least sensitivity to the applied test loads exhibits the largest Hv value of 4.799 GPa, Young's moduli of 393.303 GPa, yield strength of (0.969 GPa), and elastic stiffness coefficient of 15.5574 (GPa)7/4 under the applied test load of 0.245 N. The XRD in-vestigations show that the presence of optimum vanadium impurity supports the formation of a high super-conducting phase, c-axis length, and average crystallite size. All the findings are morphologically confirmed by the SEM images. It is found that the crystallographically best crystallinity quality and view of surface morphology is observed for the optimum vanadium substitution level. All in all, new higher properties for the conductivity, crystallinity quality, surface morphology, superconducting, and microhardness parameters based on the optimum vanadium replacement encourage the Bi-2212 crystal system to use in much more application places.Öğe Quantum coherence and non-Markovianity in a noisy quantum tunneling problem(Springer, 2023) Mahdi, Nisreen Mohammed; Kurt, Arzu; Altıntaş, FerdiWe investigate the coherence and non-Markovianity of a quantum tunneling system whose barrier is fluctuated by a telegraph noise, and its energy gap is modulated by Gaussian noise. With the help of averaging method, the system dynamics are analytically derived, and the analytical expression for coherence measure and non-Markovianity, focusing on a narrow range of parameter regimes for both initially coherent and non-coherent states are obtained. We observe non-Markovian dynamics in a situation where the Kubo number is high. It is also found that there is no strong relation between the coherence of the system and non-Markovian dynamics except a region in which these two tend to change their behavior at the intermediate noise color for two initial states.Öğe MALTA monolithic pixel sensors in TowerJazz 180 nm technology(Elsevier, 2023) Sanchez, C. Solans; Allport, P.; Denizli, Haluk; Berlea, D. V.; Oyulmaz, Kaan Yüksel; Bortoletto, D.Depleted Monolithic Active Pixel Sensors are of highest interest at the HL-LHC and beyond for the replacement of the Pixel trackers in the outermost layers of experiments where the requirement on total area and cost effectiveness is much bigger. They aim to provide high granularity and low material budget over large surfaces with ease of integration. Our research focuses on MALTA, a radiation hard DMAPS with small collection electrode designed in TowerJazz 180 nm CMOS imaging technology and asynchronous read-out. Latest prototypes are radiation hard up to 2 x 1015 1 MeV neq/cm2 with a time resolution better than 2 ns.Öğe Radiation hardness of MALTA2, a monolithic active pixel sensor for tracking applications(IEEE-Inst Electrical Electronics Engineers Inc., 2023) Denizli, Haluk; Berlea, D. V.; Allport, P.; Tortajada, I. Asensi; Bortoletto, D; Buttar, C.MALTA is a depleted monolithic active pixel sensor (DMAPS) developed in the Tower Semiconductor 180-nm CMOS imaging process. Monolithic CMOS sensors offer advantages over current hybrid imaging sensors in terms of both increased tracking performance due to lower material budget and ease of integration and construction costs due to the integration of read-out and active sensor into one ASIC. Current research and development efforts are aimed toward radiation hard designs up to 100 Mrad in total ionizing dose (TID) and 1 x 10(15) 1 MeVn(eq)/cm(2) in nonionizing energy loss (NIEL). The design of the MALTA sensors was specifically chosen to achieve radiation hardness up to these requirements and satisfy current and future collider constraints. The current MALTA pixel architecture uses small electrodes which provide less noise, higher signal voltage, and a better power-to-performance ratio. To counteract the loss of efficiency in pixel corners, modifications to the Tower process have been implemented. The MALTA sensors have been tested during the 2021 and 2022 SPS CERN Test Beam in the MALTA telescope. The telescope ran for the whole duration of the beam time and took data to characterize the novel MALTA2 variant and the performance of irradiated samples in terms of efficiency and cluster size. These campaigns show that MALTA is an interesting prospect for HL-LHC and beyond collider experiments, providing both very good tracking capabilities and radiation hardness in harsh radiation environments.
