01. Araştırma Çıktıları | TR-Dizin | WoS | Scopus | PubMed

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Citation - WoS: 2
Citation - Scopus: 2
Active Particle Aggregate on Complex Bubble Surfaces
(Canadian Science Publishing, Nrc Research Press, 2018) Akguc, Gursoy B.
Recently, colloids have been shown to form complex structures on bubble surfaces on demand. With the help of a high power pulse laser shining on a thin water film, water bubbles can be formed and heat unbalance creates a convective flow, which carries colloids on the surface of these water bubbles to form aggregates. Here, active particles are studied in a similar setup and conditions are laid out to form aggregates on water bubble surfaces. The effect of motility and chirality of active particles on formation of aggregate are discussed. The simulation results obtained here will hopefully help the experimental endeavors in future.
Aktif Nano Parçacıkların İki Boyutlu Karmaşık Yüzeylerde İncelenmesi; Yaşayan Kristal Oluşumu
(2021) Zafer, Aytürk Hamdi; Akgüç, Gürsoy Bozkurt
İnce su filmindeki aktif küresel parçacıklar birisi lazer kaynağı ile ısıtılmış komşu iki su kabarcığı üzerinde ısıdan dolayı oluşan su akıntısı yardımıyla birikirler. Bu özel geometri daha önce pasif parçacıklar için yapılan deneyimizden alınmıştır. Su akışı zamanla değişen birikinti dolayısı ile farklılık gösterir bu anlamda aktif bir akım olarak düşünülebilir. Ayrıca parçacıkların arasında bir zaman bağımlı geri besleme kuvveti de eklenmiştir. Geri beslemenin çekici veya itici olması incelenmiş çekici bir geri besleme ile öbekleşmeler gözlenmiş birikintinin daha kolay olduğu gözlemlenmiştir. Hem aktif su akımı hem de geri besleme parçacıkların çift korelasyonları ve ortalama uzaklaşma bilgilerine bakılarak tartışılmıştır.
Central Limit Behavior at the Edge of Chaos in the Z-Logistic Map
(American Physical Society, 2025) Saberi, Abbas Ali; Tirnakli, Ugur; Tsallis, Constantino
We focus on the Feigenbaum-Coullet-Tresser point of the dissipative one-dimensional z-logistic map x(t+1) = 1-a|x(t )|(z) (z 1). We show that sums of iterates converge to q-Gaussian distributions P-q(y) = P-q(0) exp(q)(-beta(q)y(2)) = P-q(0 )[1 + (q-1)beta(q) y(2)](1/(1-q))(q >= 1; beta(q) > 0), which optimize the nonadditive entropic functional Sq under simple constraints. We propose and justify heuristically a closed-form prediction for the entropic index, q(z) = 1 + 2/(z + 1), and validate it numerically via data collapse for typical z values. The formula captures how the limiting law depends on the nonlinearity order and implies finite variance for z > 2 and divergent variance for 1 <= z <= 2. These results extend edge-of-chaos central limit behavior beyond the standard (z = 2) case and provide a simple predictive law for unimodal maps with varying maximum order.
Citation - WoS: 1
Citation - Scopus: 1
Cern Super Proton Synchrotron and an Alternative Design as Prebooster Ring for the Future Circular Collider E Plus E- Injector Complex
(Amer Physical Soc, 2023) Etisken, O.; Antoniou, F.; Papaphilippou, Y.; Tydecks, T.; Zimmermann, F.; Çiftçi, Abbas Kenan; Oide, K.
The Future Circular Collider (FCC) e+e- injector complex needs to produce and transport highintensity e+ and e- beams at a fast repetition rate for topping up at collision energy. Two options are considered for a preaccelerator ring, to be used for an intermediate accumulation and acceleration before the bunches are transferred to the high-energy booster. One option is a slightly modified Super Proton Synchrotron (SPS), and the other is designing a new ring. We explore the needs and parameters of the existing SPS as prebooster ring and also develop a conceptual design of an alternative accelerator ring. After establishing the basic parameters, we describe the optics design and layout and discuss the single-particle linear and nonlinear dynamics optimization, including magnetic and alignment errors. In addition, we present synchrotron radiation power studies and analytical estimates of various collective effects for both prebooster ring design options, including space charge, intrabeam scattering, longitudinal microwave instability, transverse mode coupling instability, ion effects, electron cloud, and coherent synchrotron radiation.
Citation - WoS: 2
Citation - Scopus: 1
Conceptual Design of a Pre-Booster Ring for Fcc E(+)e(-) Injector
(Iop Publishing Ltd, 2017) Etisken, O.; Papaphilippou, Y.; Ciftci, A. K.
The FCC-e(+)e(-) injector complex needs to produce and to transport a high-intensity e(+)/e(-) beam at a fast repetition rate of about 0.1 Hz for topping up the collider at its collision energy. A basic parameter set exists for all the collider energies, assuming a 10 GeV linac operating with a large number of bunches being accumulated in the existing SPS, which serves as pre-accelerator and damping ring before the bunches are transferred to the high-energy booster. The purpose of this study is to provide the conceptual design of an alternative accelerator ring, replacing the SPS in the present scheme. This ring will have injection energy of 6 GeV and extraction energy of 20 GeV. In this study, the basic parameters of the ring are established, including the optics design and layout. Preliminary consideration for non-linear dynamics optimization and the impact of intra beam scattering are also presented.
Citation - WoS: 3
Citation - Scopus: 3
Continuous Dynamical Decoupling and Decoherence-Free Subspaces for Qubits With Tunable Interaction
(Springer, 2019) Yalcinkaya, I.; Cakmak, B.; Karpat, G.; Fanchini, F. F.
Protecting quantum states from the decohering effects of the environment is of great importance for the development of quantum computation devices and quantum simulators. Here, we introduce a continuous dynamical decoupling protocol that enables us to protect the entangling gate operation between two qubits from the environmental noise. We present a simple model that involves two qubits which interact with each other with a strength that depends on their mutual distance and generates the entanglement among them, as well as in contact with an environment. The nature of the environment, that is, whether it acts as an individual or common bath to the qubits, is also controlled by the effective distance of qubits. Our results indicate that the introduced continuous dynamical decoupling scheme works well in protecting the entangling operation. Furthermore, under certain circumstances, the dynamics of the qubits naturally led them into a decoherence-free subspace which can be used complimentary to the continuous dynamical decoupling.
Citation - WoS: 5
Citation - Scopus: 4
Design and Optimisation of the Positron Production Chain for Clic From the Target To the Damping Ring
(Elsevier Science Bv, 2017) Bayar, C.; Ciftci, A. K.; Doebert, S.; Latina, A.
The CLIC Positron source has been designed to produce non-polarised positron beams using a hybrid target composed of a crystal followed by an amorphous target. After production, positrons are captured and accelerated to 200 MeV in the pre-injector linac and subsequently accelerated further up to 2.86 GeV in the injector linac. At this point they enter the pre-damping ring and afterwards the main damping ring to obtain the necessary beam quality for a linear collider. In this study, we have designed and optimised the beam transport and acceleration from the target to the pre-damping ring which has a limiting transverse and longitudinal acceptance. The goal of the study was to maximise the positron yield accepted by the pre-damping ring. (C) 2017 The Authors. Published by Elsevier B.V.
Citation - WoS: 1
Citation - Scopus: 1
Design of a Virtual Mca and Its Use in Radiation Spectrometer
(Maik Nauka/Interperiodica/Springer, 2022) Tektas, Gozde; Celiktas, Cuneyt
In the present study, a virtual MCA (multichannel analyzer) which could be used in a radiation detection spectrometer was developed by writing a code through software functions. It was compared with a real MCA, and so the performance of the virtual MCA was tested. Spectra were displayed in the real MCA and the virtual MCA for different source-to-detector distances. Total counts, photopeak counts, live time, percentage dead time and energy resolution values obtained from both MCAs were compared with each other. Besides, obtained results and the spectrum shapes displayed in the virtual MCA were compared with those of the real one.
Developing of a Virtual Mca To Acquire a Radiation Spectrum
(2021) Tektaş, Gözde; Çeliktaş, Cüneyt
A virtual MCA (Multichannel Analyzer) was developed via a software in the computerenvironment to display a spectrum for radiation detection experiments. A pulse generator thatsubstitutes for a particle detector was used to supply the signals to be analyzed in the MCA. Thepulses from the generator were analyzed by a virtual MCA and a real MCA. Channel numbersand the number of counts in these channels, and the total counts obtained from the virtual MCAand the real MCA were compared with each other. For comparing of the number of counts, datawere accumulated in different acquisition times. After comparison of the results, it wasobserved that the virtual MCA was quite successful as well as a real MCA. It was concludedfrom the introduced work that the developed virtual MCA would be able to use in a radiationdetection system like a real one.
A Different Way To Obtain Mass Attenuation Coefficients of H, Ag, and U Elements for Gamma Energies Between 0.001 To 100 000 MeV
(Taylor & Francis Inc, 2026) Tektas, Gozde; Celiktas, Cuneyt
This work focuses on a novel way to calculate the mass attenuation coefficients (MACs) of the elements. A code was written under LabVIEW software to perform this calculation. The MAC values of three different elements (H, Ag, and U) with low, medium and high atomic numbers were calculated for different gamma energies to test the developed code. Four different interpolation methods, namely, nearest, linear, spline, and cubic hermite, were used to compute the MACs in the code. Photon energies and cross-section values used in the XCOM program were entered into the written code. The total cross-section value for each energy was computed by the code, and these energies and the total cross-section values were used by an interpolation function in the code.The MAC results from the code were compared with those of the XCOM program. This comparison was performed for the energies used and unused in the interpolation process. For example, for the 1.000 x 10-3 MeV photon energy used in the interpolation process, the MAC values from the code using all methods for the H, Ag, and U elements were 7.214 x 100 cm2/g, 7.037 x 103 cm2/g, and 6.627 x 103 cm2/g, respectively, which are the same as the values in XCOM. As a result of these comparisons, the most appropriate interpolation methods were determined for the calculation of the MACs of the elements. Besides, just like in the XCOM program, the code includes a graph showing the MACs versus the photon energies. The graphs from the code and XCOM were also compared with each other. The obtained results suggest that the introduced code could be used alternatively to obtain the MACs of the elements.
Citation - WoS: 13
Citation - Scopus: 13
Disorder-Free Localization in Quantum Walks
(Amer Physical Soc, 2021) Danaci, B.; Yalcinkaya, I; Cakmak, B.; Karpat, G.; Kelly, S. P.; Subasi, A. L.; Yalçınkaya, İ.; Danacı, B.; Subaşı, A.L.
The phenomenon of localization usually happens due to the existence of disorder in a medium. Nevertheless, certain quantum systems allow dynamical localization solely due to the nature of internal interactions. We study a discrete time quantum walker which exhibits disorder-free localization. The quantum walker moves on a one-dimensional lattice and interacts with on-site spins by coherently rotating them around a given axis at each step. Since the spins do not have dynamics of their own, the system poses the local spin components along the rotation axis as an extensive number of conserved moments. When the interaction is weak, the spread of the walker shows subdiffusive behavior having downscaled ballistic tails in the evolving probability distribution at intermediate timescales. However, as the interaction gets stronger the walker gets completely localized in total absence of disorder in both lattice and initial state. Using a matrix-product-state ansatz, we investigate the relaxation and entanglement dynamics of the on-site spins due to their coupling with the quantum walker. Surprisingly, we find that, even in the delocalized regime, entanglement growth and relaxation occur slowly, unlike majority of the other models displaying a localization transition.
E-6 Predicted Isosinglet Quarkonium Formation
(Canadian Science Publishing, Nrc Research Press, 2018) Caglar, C.; Ciftci, R.; Ciftci, A. K.
An extension of the Standard Model to the local gauge group SU(3)(C) circle times SU(3)(L) circle times U(1)(X), which is a subgroup of electroweak-strong unification group E-6, predicts isosinglet quarks. In this study, isosinglet quarkonium formation conditions are investigated.
Citation - WoS: 2
Citation - Scopus: 2
Energy Distributions of Frenkel-Kontorova Atomic Chains: Transition From Conservative To Dissipative Dynamics
(Elsevier, 2024) Afsar, Özgür; Tırnaklı, Uğur
We investigate energy distributions of Frenkel-Kontorova-type atomic chains generated from large number of independent identically distributed (iid) random initial atomic positionings under two cases. In the first case, atoms at the free-end chains without dissipation (conservative case) are only coupled to one other atom, whereas each atom inside the bulk is coupled to its 2 nearest neighbours. Here, atoms located at the chain are all at the same type. Such kind of systems can be modelled by conservative standard map. We show that, when the coupling is non-linear (which leads chaotic arrangement of the atoms) for energy distribution, the Boltzmann-Gibbs statistical mechanics is constructed, namely, exponential form emerges as Boltzmann factor P(E)proportional to e(-beta E). However, when the coupling is linear (which leads linear arrangement of the atoms) the Boltzmann-Gibbs statistical mechanics fails and the exponential distribution is replaced by a q-exponential form, which generalizes the Boltzmann factor as P(E)proportional to eq(-beta)q(E)=[1-(1-q)beta E-q](1/(1-q)). We also show for each type of atom localization with N number of atoms, beta (or beta(q)) values can be given as a function of 1/N. In the second case, although the couplings among the atoms are exactly the same as the previous case, atoms located at the chain are now considered as being at different types. We show that, for energy distribution of such linear chains, each of the distributions corresponding to different dissipation parameters (gamma) are in the q-exponential form. Moreover, we numerically verify that beta(q )values can be given as a linear function of 1/& sum;(N)(n=1)(1-gamma)((n-2)). On the other hand, although energy distributions of the chaotic chains for different dissipation parameters are in exponential form, a linear scaling between beta and gamma values cannot be obtained. This scaling is possible if the energies of the chains are scaled with 1/(1-gamma)(-N). For both cases, clear data collapses among distributions are evident.
Citation - WoS: 25
Citation - Scopus: 26
Entropic Uncertainty Relation Under Correlated Dephasing Channels
(Canadian Science Publishing, Nrc Research Press, 2018) Karpat, Goktug
Uncertainty relations are a characteristic trait of quantum mechanics. Even though the traditional uncertainty relations are expressed in terms of the standard deviation of two observables, there exists another class of such relations based on entropic measures. Here we investigate the memory-assisted entropic uncertainty relation in an open quantum system scenario. We study the dynamics of the entropic uncertainty and its lower bound, related to two incompatible observables, when the system is affected by noise, which can be described by a correlated Pauli channel. In particular, we demonstrate how the entropic uncertainty for these two incompatible observables can be reduced as the correlations in the quantum channel grow stronger.
Citation - WoS: 5
Citation - Scopus: 6
Entropy Production in Non-Markovian Collision Models: Information Backflow Vs. System-Environment Correlations
(Mdpi, 2022) Senyasa, Huseyin T.; Kesgin, Sahinde; Karpat, Goktug; Cakmak, Baris
We investigate the irreversible entropy production of a qubit in contact with an environment modelled by a microscopic collision model in both Markovian and non-Markovian regimes. Our main goal is to contribute to the discussions on the relationship between non-Markovian dynamics and negative entropy production rates. We employ two different types of collision models that do or do not keep the correlations established between the system and the incoming environmental particle, while both of them pertain to their non-Markovian nature through information backflow from the environment to the system. We observe that as the former model, where the correlations between the system and environment are preserved, gives rise to negative entropy production rates in the transient dynamics, the latter one always maintains positive rates, even though the convergence to the steady-state value is slower as compared to the corresponding Markovian dynamics. Our results suggest that the mechanism underpinning the negative entropy production rates is not solely non-Markovianity through information backflow, but rather the contribution to it through established system-environment correlations.
Citation - WoS: 8
Citation - Scopus: 9
Esr Dosimetric Properties of Gamma Irradiated Different Origin Eyeglass Samples
(Pergamon-Elsevier Science Ltd, 2021) Karaaslan, Hulya; Engin, Birol
In the present research, mineral and organic origin eyeglasses (CR-39) were examined with respect to their potential application in the dosimetry of ionizing radiation by using electron spin resonance (ESR) technique. Before irradiation, organic and mineral origin eyeglasses did not exhibit any ESR signal. But they do produce radiation-induced ESR spectra after gamma irradiation. The variations of the radiation-induced resonance signals of organic and mineral origin eyeglasses with microwave power and modulation amplitude were investigated and the optimum spectrometer operating conditions were determined. The dose-response curves of the organic and mineral origin eyeglasses exposed to gamma radiations were found to be described well by a linear and single exponential saturation functions in the dose ranges of 0.1-10 and 0.05-10 kGy, respectively. For mineral eyeglasses this behavior was linear at lower doses (0.05-1 kGy). Despite the observed fading with time in the signal intensity, measurable ESR signals were obtained even 54 days after irradiation for organic origin eyeglass, while the corresponding value for the mineral eyeglass was 154 days. The study also showed that the thermal stability of the radiation-induced ESR signal of mineral eyeglass sample was higher than the signal of organic origin eyeglass.
Citation - WoS: 21
Citation - Scopus: 23
Estimating the Degree of Non-Markovianity Using Machine Learning
(Amer Physical Soc, 2021) Fanchini, Felipe F.; Karpat, Goktug; Rossatto, Daniel Z.; Norambuena, Ariel; Coto, Raul
In the last few years, the application of machine learning methods has become increasingly relevant in different fields of physics. One of the most significant subjects in the theory of open quantum systems is the study of the characterization of non-Markovian memory effects that emerge dynamically throughout the time evolution of open systems as they interact with their surrounding environment. Here we consider two well-established quantifiers of the degree of memory effects, namely, the trace distance and the entanglement-based measures of non-Markovianity. We demonstrate that using machine learning techniques, in particular, support vector machine algorithms, it is possible to estimate the degree of non-Markovianity in two paradigmatic open system models with high precision. Our approach can be experimentally feasible to estimate the degree of non-Markovianity, since it requires a single or at most two rounds of state tomography.
Citation - WoS: 541
Citation - Scopus: 682
FCC Physics Opportunities: Future Circular Collider Conceptual Design Report Volume 1
(Springer, 2019) Abada, A.; Abbrescia, M.; AbdusSalam, S. S.; Abdyukhanov, I.; Fernandez, J. Abelleira; Abramov, A.; Çiftçi, Abbas Kenan
We review the physics opportunities of the Future Circular Collider, covering its e(+)e(-), pp, ep and heavy ion programmes. We describe the measurement capabilities of each FCC component, addressing the study of electroweak, Higgs and strong interactions, the top quark and flavour, as well as phenomena beyond the Standard Model. We highlight the synergy and complementarity of the different colliders, which will contribute to a uniquely coherent and ambitious research programme, providing an unmatchable combination of precision and sensitivity to new physics.
Citation - WoS: 585
Citation - Scopus: 627
Fcc-Hh: the Hadron Collider: Future Circular Collider Conceptual Design Report Volume 3
(Springer Heidelberg, 2019) Abada, A.; Abbrescia, M.; AbdusSalam, S. S.; Abdyukhanov, I.; Abelleira Fernandez, J.; Abramov, A.; Çiftçi, Abbas Kenan
In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100TeV. Its unprecedented centre of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries.
Citation - WoS: 1
Citation - Scopus: 1
Feedback and Reactive Flow Effects on Living Crystal Formation
(Elsevier, 2022) Zafer, Ayturk Hamdi; Akguc, Gursoy B.
Active spherical particles in a water film form aggregate on two neighboring water bubbles, where one of the bubbles' half surface is heated by a laser source, creating a convective flow field. The specific geometry is similar to the experimental setup we used for colloidal particles (Ilday et al., 2017). Water flow is considered reactive during the simulation due to changing flow field, as well as temperature field. A feedback interaction is introduced, which may be due to the concentration of particles in some region of fluid, effectively a time-dependent accumulation. We show the effect of attractive and repulsive feedback forces, and observe, under attractive feedback, the formation of patches of aggregate distributed all over the space, and eventually a greater aggregate formation on the bubble surface. Reactive flow effects, with and without feedback effects, are analyzed, by examining the pair correlation and mean square displacement indicators, as well as the single-particle trajectories. (C) 2021 Elsevier B.V. All rights reserved.

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