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2015

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Factors Affecting Parental Involvement In Education: The Analysis Of Literature, Javid Jafarov Jan 2015

Factors Affecting Parental Involvement In Education: The Analysis Of Literature, Javid Jafarov

Khazar Journal of Humanities and Social Sciences

This study examines the factors affecting parental involvement by evaluating and analysing literature about parental involvement in education. It also answers the questions: a) What does parental involvement mean? and 2) Why is parental involvement important? In this article more than five hundreds literatures related to the factors affecting parental involvement were evaluated and analysed. The result of the analysis of literature showed that there are many factors influencing parental involvement or the level of parental involvement and these factors can be parent related, school related or student related.


Campus Open Access Funds: Experiences Of The Ku “One University” Open Access Author Fund, Rachel Gyore, Allison C. Reeve, Crystal Cameron-Vedros, Deborah Ludwig, Ada Emmett Jan 2015

Campus Open Access Funds: Experiences Of The Ku “One University” Open Access Author Fund, Rachel Gyore, Allison C. Reeve, Crystal Cameron-Vedros, Deborah Ludwig, Ada Emmett

Library Faculty Publications

In the summer of 2012, librarians from the Lawrence and Kansas City campuses of the University of Kansas (KU) proposed the creation of a KU “One University” Open Access Fund (OA Author Fund) to support open access publishing for its faculty, students, and staff. KU is a major public research and teaching institution of 28,000 students and 2,600 faculty on five campuses (Lawrence, Kansas City, Overland Park, Wichita, and Salina) (http://ku.edu/about), and has been a leader in open access initiatives for many years. A working group of librarians came together to create and implement a pilot project to explore the …


Response To Intervention To Educate The Diverse Needs Of Elementary Students, James H. Mcmillan, Valerie J. Robnolt, Amy C. Hutton Jan 2015

Response To Intervention To Educate The Diverse Needs Of Elementary Students, James H. Mcmillan, Valerie J. Robnolt, Amy C. Hutton

MERC Publications

Much research has been done regarding how to implement RTI, effective strategies for RTI, and outcomes of RTI, which is not the focus of the current study. This investigation will focus on assessing the current perceptions of elementary school educators and staff on thier current understanding of and needs for more effective implementation of RTI.


Countersupermajoritarianism, Frederic Bloom, Nelson Tebbe Jan 2015

Countersupermajoritarianism, Frederic Bloom, Nelson Tebbe

Publications

How should the Constitution change? In Originalism and the Good Constitution, John McGinnis and Michael Rappaport argue that it ought to change in only one way: through the formal mechanisms set out in the Constitution’s own Article V. This is so, they claim, because provisions adopted by supermajority vote are more likely to be substantively good. The original Constitution was ratified in just that way, they say, and subsequent changes should be implemented similarly. McGinnis and Rappaport also contend that this substantive goodness is preserved best by a mode of originalist interpretation. In this Review, we press two main arguments. …


Fuzzy Sliding Mode Control Applied To A Doubly Fed Induction Generator For Wind Turbines, Sid Ahmed El Mehdi Ardjoun, Mohamed Abid Jan 2015

Fuzzy Sliding Mode Control Applied To A Doubly Fed Induction Generator For Wind Turbines, Sid Ahmed El Mehdi Ardjoun, Mohamed Abid

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper an indirect vector control using fuzzy sliding mode control is proposed for a double-fed induction generator (DFIG), applied for a wind energy conversion system in variable speed. The objective is to independently control the active and reactive power generated by the DFIG, which is decoupled by the orientation of the flux. The sliding mode control finds its strongest justification for the problem concerning the use of a robust nonlinear control law for the model uncertainties. As far as the fuzzy mode control is concerned, it aims at reducing the chattering effect. The obtained results show the increasing …


Model-Reference Sliding Mode Control Of A Three-Phase Four-Leg Voltage Source Inverter For Stand-Alone Distributed Generation Systems, Ayhan Özdemi̇r, İrfan Yazici, Zeki̇ye Erdem Jan 2015

Model-Reference Sliding Mode Control Of A Three-Phase Four-Leg Voltage Source Inverter For Stand-Alone Distributed Generation Systems, Ayhan Özdemi̇r, İrfan Yazici, Zeki̇ye Erdem

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes a discrete-time model-reference sliding mode control of three-phase four-leg voltage source inverters for stand-alone distributed generation systems. Three-phase four-leg voltage source inverters (VSIs) are used in a broad area. A discrete-time model-reference sliding mode controller, having superior advantages such as insensitivity to external disturbances, system parameter variations, and modeling errors, is applied to control the output voltage of three-phase four-leg VSIs. As a new study, the discrete-time model-reference sliding mode control with a supplemented output feedback integral controller is proposed so that the controlled output voltages of the VSI tracks the input reference signal. The controller is …


Performance Analysis Of A 500-Kwp Grid-Connected Solar Photovoltaic Power Plant In Kahramanmaraş, Şaban Yilmaz, Hasan Riza Özçalik Jan 2015

Performance Analysis Of A 500-Kwp Grid-Connected Solar Photovoltaic Power Plant In Kahramanmaraş, Şaban Yilmaz, Hasan Riza Özçalik

Turkish Journal of Electrical Engineering and Computer Sciences

In today's world, the daily need for and cost of energy sources increase and this forces industrial institutions to seek for new ways to generate their own energy. The developments in photovoltaic systems have recently drawn attention in the business world. Although their installation costs are high, they are environmentally friendly and profitable investments in the long run. The cost analysis of a large-scale photovoltaic generator in the climatic conditions of Kahramanmara\c{s} will lead the way to new investments. In this study, the modeling and cost analysis of an on-grid photovoltaic generator of 500 kW, which was installed to provide …


New Three-Dimensional Space Vector Pulse Width Modulation Of Pv-Af System Based On The Gh$\Gamma $ Coordinate System, Juan Zhou, Malong Liu, Chen Wei, Chaoxu Gao, Xiaojie Wu Jan 2015

New Three-Dimensional Space Vector Pulse Width Modulation Of Pv-Af System Based On The Gh$\Gamma $ Coordinate System, Juan Zhou, Malong Liu, Chen Wei, Chaoxu Gao, Xiaojie Wu

Turkish Journal of Electrical Engineering and Computer Sciences

The photovoltaic power generation and active filter (PV-AF) system can realize photovoltaic grid-connected power regulation, and meanwhile it can also improve the power quality of power grid effectively. The four-leg grid-connected inverter has successfully been used in the three-phase four-wire system. In this paper, a three-dimensional space vector pulse width modulation (3D-SVPWM) method based on the gh$\gamma $ coordinate system for a four-leg inverter has been proposed. As the switching vectors of the four-leg inverter are in the three-dimensional space, it is difficult to realize the complex modulation process. In order to simplify the modulation process, the reference vector is …


Stability Preservation And Power Management In Autonomous Microgrids Using Adaptive Nonlinear Droop Scheme, Sara Nourollah, Abolfazl Pirayesh, Poria Astero Jan 2015

Stability Preservation And Power Management In Autonomous Microgrids Using Adaptive Nonlinear Droop Scheme, Sara Nourollah, Abolfazl Pirayesh, Poria Astero

Turkish Journal of Electrical Engineering and Computer Sciences

This paper proposes sharing active and reactive power in autonomous voltage source inverter (VSI)-based microgrids with no physical communication links. In decentralized VSI-based microgrids, when the demand or generation changes, the output voltage of distributed generation units and the frequency of the system will also change. This study presents a novel adaptive nonlinear droop (ANLD) scheme for preserving network stability, improving the system's dynamics, and controlling power sharing in multibus microgrids in a decentralized manner. Subcontrollers are modeled in a state space and combined together so that a complete dynamic model of the network can be developed. Note that controller …


Performance Analysis Of A Low-Cost Current-Source 1-Ph Grid-Connected Pv Inverter, Gürhan Ertaşgin, Wen Liang Soong, Nesimi Ertugrul Jan 2015

Performance Analysis Of A Low-Cost Current-Source 1-Ph Grid-Connected Pv Inverter, Gürhan Ertaşgin, Wen Liang Soong, Nesimi Ertugrul

Turkish Journal of Electrical Engineering and Computer Sciences

This paper investigates the design and performance of a 150 W single-phase current-source grid-connected inverter topology that is based on a PV array and DC link inductor acting as a constant-current source. The inverter is implemented using a single boost switch, an H-bridge inverter, and a CL output filter. The inverter output current is simply controlled using the boost switch and open-loop or feedforward control. The dark I-V configuration is used to simulate two series PV modules. Comprehensive test results are obtained to validate the computer simulation results. Furthermore, the proposed inverter's ability to deliver a sinusoidal current to the …


Amorphous Core Transformers Efficiency Analysis In Turkish Electrical Distribution Systems, Fati̇h Işik, Yilmaz Uyaroğlu Jan 2015

Amorphous Core Transformers Efficiency Analysis In Turkish Electrical Distribution Systems, Fati̇h Işik, Yilmaz Uyaroğlu

Turkish Journal of Electrical Engineering and Computer Sciences

Transformers are an indispensable element in the transmission and distribution of electricity. While they are highly efficient, the increasing global demand for electrical energy has prompted efforts to improve their performance. No-load power losses constitute the majority of total losses within electrical energy distribution, especially when looking at load ratio. In recent years, some studies have found that no-load power losses of amorphous core transformers are less than those of laminated steel core transformers by as much as 60{\%} to 70{\%}. For this paper, we have manufactured an amorphous distribution transformer prototype rated 33 kV and 1 MVA. By quantifying …


Energy Economy In Regulated And Market-Based Power System: Case Study In Serbia, Mileta Zarkovic, Ivan Skokljev Jan 2015

Energy Economy In Regulated And Market-Based Power System: Case Study In Serbia, Mileta Zarkovic, Ivan Skokljev

Turkish Journal of Electrical Engineering and Computer Sciences

This study presents a possible process of simulating power plant generation planning. The process combines expected overall industry costs, associated cost uncertainty, and expected CO$_{2}$ emissions for different generations, variations of future fossil fuel costs, carbon prices, plant investment costs, and demand, including price elasticity impacts. Uncertainty in the decision stems from the elasticity of prices of fuel and electricity. The aim of this paper is to apply fuzzy numbers to power generation planning and to use a Monte Carlo simulation to check. Simulations are demonstrated through a case study of an electricity industry with coal and lignite, combined cycle …


Design, Application, And Power Performance Analyses Of A Micro Wind Turbine, Hayati̇ Mamur Jan 2015

Design, Application, And Power Performance Analyses Of A Micro Wind Turbine, Hayati̇ Mamur

Turkish Journal of Electrical Engineering and Computer Sciences

In this study, design, implementation, and power performance analyses of a micro wind turbine (MWT) system are presented. An original permanent magnet synchronous generator (PMSG) that reduced cogging torque was employed as a generator in the MWT. A novel blade form offering better performance at low wind speeds was also utilized for the MWT blades. Power performance analyses of the MWT were carried out for different wind regimes by truck testing. Performance coefficient, cut-in, and cut-out of the MWT were determined as 27.7{\%}, 2.7 m/s, and 20 m/s at the end of the truck testing, respectively. Moreover, a new supervisory …


Anisotropy Reversal Of The Upper Critical Field At Low Temperatures And Spin-Locked Superconductivity In K₂Cr₃As₃, F. F. Balakirev, T. Kong, M. Jaime, R. D. Mcdonald, C. H. Mielke, A. Gurevich, P. C. Canfield, S. L. Bud'ko Jan 2015

Anisotropy Reversal Of The Upper Critical Field At Low Temperatures And Spin-Locked Superconductivity In K₂Cr₃As₃, F. F. Balakirev, T. Kong, M. Jaime, R. D. Mcdonald, C. H. Mielke, A. Gurevich, P. C. Canfield, S. L. Bud'ko

Physics Faculty Publications

We report measurements of the anisotropic upper critical field Hc2(T) for K2Cr3As3 single crystals up to 60 T and T > 0.6K. Our results show that the upper critical field parallel to the Cr chains, H∥c2(T), exhibits a paramagnetically limited behavior, whereas the shape of the H⊥c2(T) curve (perpendicular to the Cr chains) has no evidence of paramagnetic effects. As a result, the curves H⊥c2(T) and H∥c2(T) cross at T ≈ 4K, so that the anisotropy parameter H(T)=H …


Energy-Sharing (E,2e) Collisions: Ionization Of The Inert Gases In The Perpendicular Plane, F. K. Miller, H. R. J. Walters, Colm T. Whelan Jan 2015

Energy-Sharing (E,2e) Collisions: Ionization Of The Inert Gases In The Perpendicular Plane, F. K. Miller, H. R. J. Walters, Colm T. Whelan

Physics Faculty Publications

The triple differential cross section for ionization of the inert gases He, Ne, Ar, Kr, and Xe in energy-sharing perpendicular plane geometry is investigated. Encouraging agreement with recent experiments is found using the distorted-wave Born approximation (DWBA). Mechanisms are discussed which explain the He and Ne data but which seem to be masked by the greater distortion effects in the heavier targets. The inclusion of postcollisional interaction is explored using Gamow, Nee, and Ward-Macek, Mee, factors. While both help to improve the shape of the cross section for He and Ne at the lower energies, they …


Current-Induced Depairing In The Bi₂Te₃/Fete Interfacial Superconductor, M. N. Kunchur, C. L. Dean, N. Shayesteh Moghadam, J. M. Knight, Q. L. He, H. Liu, J. Wang, R. Lortz, I. K. Sou, Alex Gurevich Jan 2015

Current-Induced Depairing In The Bi₂Te₃/Fete Interfacial Superconductor, M. N. Kunchur, C. L. Dean, N. Shayesteh Moghadam, J. M. Knight, Q. L. He, H. Liu, J. Wang, R. Lortz, I. K. Sou, Alex Gurevich

Physics Faculty Publications

We investigated current induced depairing in the Bi₂Te₃/FeTe topological insulator-chalcogenide interface superconductor. The measured depairing current density provides information on the magnetic penetration depth and superfluid density, which in turn shed light on the nature of the normal state that underlies the interfacial superconductivity.


Virtuality Distributions And Pion Transition Form Factor, A. V. Radyushkin Jan 2015

Virtuality Distributions And Pion Transition Form Factor, A. V. Radyushkin

Physics Faculty Publications

Using the example of hard exclusive transition process ᵞ*ᵞ → π⁰ at the handbag level, we outline basics of a new approach to transverse momentum dependence in hard processes. In coordinate representation, matrix elements of operators (in the simplest case, bilocal 𝒪(0, z)) describing a hadron with momentum p, are functions of (pz) and z² parametrized through virtuality distribution amplitudes (VDA) Φ(x, σ), with x being Fourier-conjugate to (pz) and σ Laplace-conjugate to z2. For intervals with z+ = 0, we introduce the transverse momentum distribution amplitude (TMDA) Ψ(x, k⊥), and write it in terms of VDA …


Question 1: Star Speeds; Question 2: Slurping Gasoline, Larry Weinstein Jan 2015

Question 1: Star Speeds; Question 2: Slurping Gasoline, Larry Weinstein

Physics Faculty Publications

One piece of evidence that the center of our galaxy contains a super-massive black hole came from measuring the speed of a star orbiting that black hole. What is the maximum speed of that star?

If instead of carrying their gas in fuel tanks, cars “slurped up” a stream of gas as they drove, how thick a stream of gas would each car need?


Question 1: "Up" — A Fermi Question About Buoyancy; Question 2: Traffic Jams, Larry Weinstein Jan 2015

Question 1: "Up" — A Fermi Question About Buoyancy; Question 2: Traffic Jams, Larry Weinstein

Physics Faculty Publications

Is it possible for a house to fly by the uplift of balloons, like in the movie "Up"? (written by R. Allart, A. Cazenave, and A. Müller, University of Geneva)

How much total time do Americans spend waiting in traffic each year? What is the total cost of this time?


Question 1: Kill The K-Cup; Question 2: Water Cooling, Larry Weinstein Jan 2015

Question 1: Kill The K-Cup; Question 2: Water Cooling, Larry Weinstein

Physics Faculty Publications

According to KillTheKCup.org, single-use non-recyclable Keurig K-cups “are killing our planet.” How large is the environmental impact of K-Cups?

How much more cooling do you get from drinking cold rather than room-temperature water on a hot day? How much do you sweat per day when the ambient temperature is about 35 °C (95 °F)?


Question 1: Shaving Time; Question 2: Half-Filling The Gas Tank, Larry Weinstein Jan 2015

Question 1: Shaving Time; Question 2: Half-Filling The Gas Tank, Larry Weinstein

Physics Faculty Publications

How much total time does a typical American spend shaving during his or her life? How much total time per year do Americans spend shaving?

How much money can you save by only half-filling your car's gas tank to reduce weight?


Transverse Momentum Dependent (Tmd) Parton Distribution Functions: Status And Prospects, R. Angeles-Martinez, A. Bacchetta, I. I. Balitsky, D. Boer, M. Boglione, R. Boussarie, F. A. Ceccopieri, I. O. Cherednikov, P. Connor, M. G. Echevarria, G. Ferrera, J. Grados Luyando, F. Hautmann, H. Jung, T. Kasemets, K. Kutak, J. P. Lansberg, A. Lelek, G. Lykasov, J. D. Madrigal Martinez, P. J. Mulders, E. R. Nocera, E. Petreska, C. Pisano, R. Plaċakyte, V. Radescu, M. Radici, G. Schnell, I. Scimemi, A. Signori, L. Szymanowski, S. Taheri Monfared, F.F. Van Der Veken, H. J. Van Haevermaet, P. Van Mechelen, A. A. Vladimirov, S. Wallon Jan 2015

Transverse Momentum Dependent (Tmd) Parton Distribution Functions: Status And Prospects, R. Angeles-Martinez, A. Bacchetta, I. I. Balitsky, D. Boer, M. Boglione, R. Boussarie, F. A. Ceccopieri, I. O. Cherednikov, P. Connor, M. G. Echevarria, G. Ferrera, J. Grados Luyando, F. Hautmann, H. Jung, T. Kasemets, K. Kutak, J. P. Lansberg, A. Lelek, G. Lykasov, J. D. Madrigal Martinez, P. J. Mulders, E. R. Nocera, E. Petreska, C. Pisano, R. Plaċakyte, V. Radescu, M. Radici, G. Schnell, I. Scimemi, A. Signori, L. Szymanowski, S. Taheri Monfared, F.F. Van Der Veken, H. J. Van Haevermaet, P. Van Mechelen, A. A. Vladimirov, S. Wallon

Physics Faculty Publications

We review transverse momentum dependent (TMD) parton distribution functions, their application to topical issues in high-energy physics phenomenology, and their theoretical connections with QCD resummation, evolution and factorization theorems. We illustrate the use of TMDs via examples of multi-scale problems in hadronic collisions. These include transverse momentum qT spectra of Higgs and vector bosons for low qT, and azimuthal correlations in the production of multiple jets associated with heavy bosons at large jet masses. We discuss computational tools for TMDs, and present the application of a new tool, TMDLIB, to parton density fits and parameterizations.


Resonant 𝜋⁺𝜸 → 𝜋⁺𝜋⁰ Amplitude From Quantum Chromodynamics, Raúl A. Briceño, Jozef J. Dudek, Robert G. Edwards, Christian J. Shultz, Christopher E. Thomas, David J. Wilson Jan 2015

Resonant 𝜋⁺𝜸 → 𝜋⁺𝜋⁰ Amplitude From Quantum Chromodynamics, Raúl A. Briceño, Jozef J. Dudek, Robert G. Edwards, Christian J. Shultz, Christopher E. Thomas, David J. Wilson

Physics Faculty Publications

We present the first ab initio calculation of a radiative transition of a hadronic resonance within quantum chromodynamics (QCD). We compute the amplitude for 𝜋𝜋→𝜋𝜸⋆, as a function of the energy of the 𝜋𝜋 pair and the virtuality of the photon, in the kinematic regime where 𝜋𝜋 couples strongly to the unstable ρ resonance. This exploratory calculation is performed using a lattice discretization of QCD with quark masses corresponding to mπ ≈ 400  MeV. We obtain a description of the energy dependence of the transition amplitude, constrained at 48 kinematic points, that we can analytically continue …


Nitrogen Doping Study In Ingot Niobium Cavities, Pashupati Dhakal, Gianluigi Ciovati, Peter Kneisel, Ganapati Rao Myneni, Junki Makita Jan 2015

Nitrogen Doping Study In Ingot Niobium Cavities, Pashupati Dhakal, Gianluigi Ciovati, Peter Kneisel, Ganapati Rao Myneni, Junki Makita

Physics Faculty Publications

Thermal diffusion of nitrogen in superconducting radio frequency cavities at temperatures around 800C has resulted in the increase in quality factor with a low-field Q-rise. However, the maximum accelerating gradients of these doped cavities often reduces below the values achieved by standard treatments. In this contribution, we present the results of the nitrogen diffusion into ingot niobium cavities subjected to successive material removal from the inner cavity surface by electropolishing in an effort to explore the underlying cause for the gradient degradation.


First Measurement Of The Polarization Observable E In The P→ (Ɣ→, Π+) In Reaction Up To 2.25 Gev, S. Strauch, W. J. Briscoe, M. Döring, E. Klempt, V. A. Nikonov, E. Pasyuk, D. Rönchen, A.V. Sarantsev, I. Strakovsky, R. Workman, K. P. Adhikari, D. Adikaram, L. El Fassi Jan 2015

First Measurement Of The Polarization Observable E In The P→ (Ɣ→, Π+) In Reaction Up To 2.25 Gev, S. Strauch, W. J. Briscoe, M. Döring, E. Klempt, V. A. Nikonov, E. Pasyuk, D. Rönchen, A.V. Sarantsev, I. Strakovsky, R. Workman, K. P. Adhikari, D. Adikaram, L. El Fassi

Physics Faculty Publications

First results from the longitudinally polarized frozen-spin target (FROST) program are reported. The double-polarization observable E, for the reaction ɣ→p→→π+n, has been measured using a circularly polarized tagged-photon beam, with energies from 0.35 to 2.37 GeV. The final-state pions were detected with the CEBAF Large Acceptance Spectrometer in Hall B at the Thomas Jefferson National Accelerator Facility. These polarization data agree fairly well with previous partial-wave analyses at low photon energies. Over much of the covered energy range, however, significant deviations are observed, particularly in the high-energy region where high-L multipoles contribute. The data have been …


Corrigendum To "Suppression Of ϒ Production In D + Au And Au + Au Collisions At √Sɴɴ = 200 Gev" (Phys. Lett. B Vol 735 (2014) 127-137), J. Adamczyk, J. K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, J. Alford, C. D. Anson, A. Aparin, D. Arkhipkin, S. Bültmann Jan 2015

Corrigendum To "Suppression Of ϒ Production In D + Au And Au + Au Collisions At √Sɴɴ = 200 Gev" (Phys. Lett. B Vol 735 (2014) 127-137), J. Adamczyk, J. K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, J. Alford, C. D. Anson, A. Aparin, D. Arkhipkin, S. Bültmann

Physics Faculty Publications

No abstract provided.


Isolation Of Flow And Nonflow Correlations By Two And Four Particle Cumulant Measurements Of Azimuthal Harmonics In √Sɴɴ = Gev Au+Au Collisions, N. M. Abdelwahab, L. Adamczyk, J. K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, J. Alford, C. D. Anson, A. Aparin, S. Bültmann Jan 2015

Isolation Of Flow And Nonflow Correlations By Two And Four Particle Cumulant Measurements Of Azimuthal Harmonics In √Sɴɴ = Gev Au+Au Collisions, N. M. Abdelwahab, L. Adamczyk, J. K. Adkins, G. Agakishiev, M. M. Aggarwal, Z. Ahammed, I. Alekseev, J. Alford, C. D. Anson, A. Aparin, S. Bültmann

Physics Faculty Publications

A data-driven method was applied to Au+Au collisions at √Sɴɴ = 200 GeV made with the STAR detector at RHIC to isolate pseudorapidity distance Δ η-dependent and Δ η-independent correlations by using two- and four-particle azimuthal cumulant measurements. We identified a Δ η-independent component of the correlation, which is dominated by anisotropic flow and flow fluctuations. It was also found to be independent of η within the measured range of pseudorapidity | η | < 1. In 20-30% central Au+Au collisions, the relative flow fluctuation was found to be 34% ± 2%(stat.) ± 3%(sys.) for particles with transverse momentum pT less than 2 GeV/c. The Δ η-dependent part, attributed to nonflow correlations, is found to be 5% ± 2%(sys.) relative to the flow of the …


The Heavy Photon Search Test Detector, M. Battaglieri, S. Boyarinov, S. Bueltmann, V. Burkert, A. Celentano, G. Charles, W. Cooper, C. Cuevas, N. Dashyan, R. Devita, L. B. Weinstein Jan 2015

The Heavy Photon Search Test Detector, M. Battaglieri, S. Boyarinov, S. Bueltmann, V. Burkert, A. Celentano, G. Charles, W. Cooper, C. Cuevas, N. Dashyan, R. Devita, L. B. Weinstein

Physics Faculty Publications

The Heavy Photon Search (HPS), an experiment to search for a hidden sector photon in fixed target electroproduction, is preparing for installation at the Thomas Jefferson National Accelerator Facility (JLab) in the Fall of 2014. As the first stage of this project, the HPS Test Run apparatus was constructed and operated in 2012 to demonstrate the experiment׳s technical feasibility and to confirm that the trigger rates and occupancies are as expected. This paper describes the HPS Test Run apparatus and readout electronics and its performance. In this setting, a heavy photon can be identified as a narrow peak in the …


Beam-Energy-Dependent Two-Pion Interferometry And The Freeze-Out Eccentricity Of Pions Measured In Heavy Ion Collisions At The Star Detector, L. Adamczyk, J.K. Adkins, G. Agakishiev, M.M. Aggarwal, Z. Ahammed, I. Koralt, Star Collaboration Jan 2015

Beam-Energy-Dependent Two-Pion Interferometry And The Freeze-Out Eccentricity Of Pions Measured In Heavy Ion Collisions At The Star Detector, L. Adamczyk, J.K. Adkins, G. Agakishiev, M.M. Aggarwal, Z. Ahammed, I. Koralt, Star Collaboration

Physics Faculty Publications

We present results of analyses of two-pion interferometry in Au + Au collisions at root s(NN) = 7.7, 11.5, 19.6, 27, 39, 62.4, and 200 GeV measured in the STAR detector as part of the BNL Relativistic Heavy Ion Collider Beam Energy Scan program. The extracted correlation lengths (Hanbury-Brown-Twiss radii) are studied as a function of beam energy, azimuthal angle relative to the reaction plane, centrality, and transverse mass (m(T)) of the particles. The azimuthal analysis allows extraction of the eccentricity of the entire fireball at kinetic freeze-out. The energy dependence of this observable is expected to be sensitive to …


Λλ Correlation Function In Au + Au Collisions At √S(Nn)=200 Gev, L. Adamczyk, J. K. Adkins, G. Agakishiev, M. M. Aggarwal, S. Bültmann, I. Koralt Jan 2015

Λλ Correlation Function In Au + Au Collisions At √S(Nn)=200 Gev, L. Adamczyk, J. K. Adkins, G. Agakishiev, M. M. Aggarwal, S. Bültmann, I. Koralt

Physics Faculty Publications

We present ΛΛ correlation measurements in heavy-ion collisions for Au + Au collisions at √sNN = 200 GeV using the STAR experiment at the Relativistic Heavy-Ion Collider. The Lednicky-Lyuboshitz analytical model has been used to fit the data to obtain a source size, a scattering length and an effective range. Implications of the measurement of the ΛΛ correlation function and interaction parameters for dihyperon searches are discussed.