208 research outputs found

    An accurate Rb density measurement method for a plasma wakefield accelerator experiment using a novel Rb reservoir

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    A method to accurately measure the density of Rb vapor is described. We plan on using this method for the Advanced Wakefield (AWAKE)~\cite{bib:awake} project at CERN , which will be the world's first proton driven plasma wakefield experiment. The method is similar to the hook~\cite{bib:Hook} method and has been described in great detail in the work by W. Tendell Hill et. al.~\cite{bib:densitymeter}. In this method a cosine fit is applied to the interferogram to obtain a relative accuracy on the order of 1%1\% for the vapor density-length product. A single-mode, fiber-based, Mach-Zenhder interferometer will be built and used near the ends of the 10 meter-long AWAKE plasma source to be able to make accurate relative density measurement between these two locations. This can then be used to infer the vapor density gradient along the AWAKE plasma source and also change it to the value desired for the plasma wakefield experiment. Here we describe the plan in detail and show preliminary results obtained using a prototype 8 cm long novel Rb vapor cell.Comment: 5 pages 9 figure

    Interactive Scientific Visualization of Fluid Flow Simulation Data Using AR Technology-Open-Source Library OpenVisFlow

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    Computational fluid dynamics (CFD) are being used more and more in the industry to understand and optimize processes such as fluid flows. At the same time, tools such as augmented reality (AR) are becoming increasingly important with the realization of Industry 5.0 to make data and processes more tangible. Placing the two together paves the way for a new method of active learning and also for an interesting and engaging way of presenting industry processes. It also enables students to reinforce their understanding of the fundamental concepts of fluid dynamics in an interactive way. However, this is not really being utilized yet. For this reason, in this paper, we aim to combine these two powerful tools. Furthermore, we present the framework of a modular open-source library for scientific visualization of fluid flow “OpenVisFlow” which simplifies the creation of such applications and enables seamless visualization without other software by allowing users to integrate the visualization step into the simulation code. Using this framework and the open-source extension AR-Core, we show how a new markerless visualization tool can be implemented

    A Study on Sibling Relationships, Life Satisfaction and Loneliness Level of Adolescents

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    The purpose of this study was to examine the relation between sibling relationships, life satisfaction, and the loneliness level of adolescents with regard to gender, order of birth, and sibling dyads. The study group consisted of 382 (209 female, 173 male) students in total, who were studying at high schools (regular high school, vocational high school, Anatolian High School, private colleges) selected from KarĆŸÄ±yaka District in the city of Ä°zmir, Turkey. The data collection tools used were the Life Span Sibling Relationship Scale, Life Satisfaction Scale, and Ucla Loneliness Scale III. The multivariate analysis of variance (MANOVA) was used for the analysis of data. The results from the research demonstrated that gender, birth order, and sibling dyads led to significant differences in life satisfaction, level of loneliness, and sibling relationships. In line with the results obtained from the research, it could be recommended that sibling relationships in the Turkish culture should be examined in terms of various age groups and different variables, and their psychosocial consequences should be subject to research

    Effectiveness of dialectical behavior therapy-online group skills training during the pandemic: A pilot study

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    Dialectical Behavior Therapy (DBT) was developed by Linehan for clients with borderline personality disorder. It is based on behaviorist approach, Zen Buddhism, and dialectical philosophy. There are four components: individual session, group skills training, telephone coaching, and consultation team. DBT group skill training consists of four modules in total, including mindfulness, interpersonal effectiveness, stress tolerance, and emotion regulation skills. Many studies have been conducted on the effectiveness of DBT and DBT group skills training. In this study, the effectiveness of 8-week DBT group skill training in university students on depression, anxiety, and stress levels during the pandemic was investigated. In addition, the improvements in emotion regulation, mindfulness, and interpersonal effectiveness skills were observed. A total of 17 women, who were undergraduate students between the ages of 18-24, participated in the study. An online self-evaluation form was sent to the participants and feedback was given to the applicants by phone call. Sociodemographic Information Form, the Five Facet Mindfulness Questionnaire-Short Form, Difficulties in Emotion Regulation Scale-Brief Form, Interpersonal Competence Questionnaire-Short Form, and Depression Anxiety Stress Scale were sent online to the selected participants before participating in the group skill training, after the 4th session, and at the end of the 8th week. According to the results, DBT group skill training was found to be helpful in reducing depression, anxiety, and stress levels. In addition, an increase was observed in emotion regulation and interpersonal competence skills

    Simulating MADMAX in 3D: Requirements for dielectric axion haloscopes

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    We present 3D calculations for dielectric haloscopes such as the currently envisioned MADMAX experiment. For ideal systems with perfectly flat, parallel and isotropic dielectric disks of finite diameter, we find that a geometrical form factor reduces the emitted power by up to 30 % compared to earlier 1D calculations. We derive the emitted beam shape, which is important for antenna design. We show that realistic dark matter axion velocities of 10-3 c and inhomogeneities of the external magnetic field at the scale of 10 % have negligible impact on the sensitivity of MADMAX. We investigate design requirements for which the emitted power changes by less than 20 % for a benchmark boost factor with a bandwidth of 50 MHz at 22 GHz, corresponding to an axion mass of 90 ” eV. We find that the maximum allowed disk tilt is 100 ” m divided by the disk diameter, the required disk planarity is 20 ” m (min-to-max) or better, and the maximum allowed surface roughness is 100 ” m (min-to-max). We show how using tiled dielectric disks glued together from multiple smaller patches can affect the beam shape and antenna coupling. © 2021 The Author(s)

    AWAKE: A proton-driven plasma wakefield acceleration experiment at CERN

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    The AWAKE Collaboration has been formed in order to demonstrate proton-driven plasma wakefield acceleration for the first time. This acceleration technique could lead to future colliders of high energy but of a much reduced length when compared to proposed linear accelerators. The CERN SPS proton beam in the CNGS facility will be injected into a 10 m plasma cell where the long proton bunches will be modulated into significantly shorter micro bunches. These micro-bunches will then initiate a strong wakefield in the plasma with peak fields above 1 GV/m that will be harnessed to accelerate a bunch of electrons from about 20 MeV to the GeV scale within a few meters. The experimental program is based on detailed numerical simulations of beam and plasma interactions. The main accelerator components, the experimental area and infrastructure required as well as the plasma cell and the diagnostic equipment are discussed in detail. First protons to the experiment are expected at the end of 2016 and this will be followed by an initial three-four years experimental program. The experiment will inform future larger-scale tests of proton-driven plasma wakefield acceleration and applications to high energy colliders.info:eu-repo/semantics/publishedVersio

    Path to AWAKE : evolution of the concept

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    This paper describes the conceptual steps in reaching the design of the AWAKE experiment currently under construction at CERN. We start with an introduction to plasma wakefield acceleration and the motivation for using proton drivers. We then describe the self-modulation instability - a key to an early realization of the concept. This is then followed by the historical development of the experimental design, where the critical issues that arose and their solutions are described. We conclude with the design of the experiment as it is being realized at CERN and some words on the future outlook. A summary of the AWAKE design and construction status as presented in this conference is given in Gschwendtner et al. [1]

    Experimental Observation of Plasma Wakefield Growth Driven by the Seeded Self-Modulation of a Proton Bunch

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    We measure the effects of transverse wakefields driven by a relativistic proton bunch in plasma with densities of 2.1 x 10(14) and 7.7 x 10(14) electrons/cm(3). We show that these wakefields periodically defocus the proton bunch itself, consistently with the development of the seeded self-modulation process. We show that the defocusing increases both along the bunch and along the plasma by using time resolved and time-integrated measurements of the proton bunch transverse distribution. We evaluate the transverse wakefield amplitudes and show that they exceed their seed value (< 15 MV/m) and reach over 300 MV/m. All these results confirm the development of the seeded self-modulation process, a necessary condition for external injection of low energy and acceleration of electrons to multi-GeV energy levels
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