MESON SPECTROSCOPY AT JLAB AT 12 GEV

2014 ◽  
Vol 35 ◽  
pp. 1460411
Author(s):  
STUART FEGAN
Keyword(s):  
Electron Beam ◽  
Nuclear Physics ◽  
Degrees Of Freedom ◽  
Real Photon ◽  
Photon Beams ◽  
Accelerator Facility ◽  
Exotic States ◽  
Meson Spectroscopy ◽  
Quark Models ◽  
New Generation

The 12 GeV upgrade to the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab will enable a new generation of experiments in hadronic nuclear physics, seeking to address fundamental questions in our understanding of QCD. The existence of exotic states, suggested by both quark models and lattice calculations, would allow gluonic degrees of freedom to be explored, and may help explain the role played by gluons in the QCD interaction. This article will review the meson spectroscopy program being planned at the lab following the 12 GeV upgrade, utilising real and quasi-real photon beams in two of the lab's four experimental halls, whose distinct capabilities will enable an extensive set of spectroscopy experiments to be performed at the same facility.

MESON SPECTROSCOPY AT CLAS

2009 ◽  
Vol 24 (02n03) ◽  
pp. 327-333
Author(s):  
◽  
MARCO BATTAGLIERI
Keyword(s):  
Particle Physics ◽  
National Laboratory ◽  
Real Photon ◽  
Hadron Structure ◽  
Photon Beams ◽  
Physics Program ◽  
Meson Spectroscopy ◽  
The Rich ◽  
Large Acceptance ◽  
Comprehensive Study

The CLAS Collaboration is operating the CLAS detector at theThomas Jefferson National Laboratory (JLab) in USA. The unique combination of the detector large acceptance and high intensity of the continuous electron beam of CEBAF has opened the way to a comprehensive study of the hadrons structure in a kinematic domain between nuclear and particle physics. Meson spectroscopy plays a central role in the physics program of the Collaboration. Many exclusive channels have been studied with virtual and real photon beams in a wide kinematic domain providing key information about the hadron structure as well as the reactions dynamic. In this contribution, the rich physics program covered by present and future experiments will be reviewed.

scholarly journals Exclusive studies on short range correlations in nuclei

2019 ◽  
Vol 204 ◽  
pp. 01016
Author(s):  
Maria Patsyuk ◽  
Or Hen ◽  
Eliezer Piasetzky
Keyword(s):  
Nuclear Physics ◽  
Short Range ◽  
Degrees Of Freedom ◽  
High Energy Physics ◽  
High Energy ◽  
Accelerator Facility ◽  
Ideal System ◽  
Nuclear Systems ◽  
Large Acceptance ◽  
Short Range Correlations

Short Range Correlations (SRC) are brief fluctuations of high relative momentum nucleon pairs. Properties of SRC have important consequences for nuclear physics, high energy physics, atomic physics, and astrophysics. SRC pairs form some of the densest states of cold matter achievable on Earth, making them an ideal system to study the partonic and nucleonic degrees of freedom in nuclear systems. Hard exclusive breakup reactions, where high-energy probes scatter on SRC pairs, are used to study such properties of SRC pairs as isospin decomposition, nuclear mass and asymmetry dependence, c.m. momentum distribution. Thomas Jefferson National Accelerator Facility (JLab) plays a key role in the SRC program. CLAS (CEBAF Large Acceptance Spectrometer), located in Hall B at JLab, has almost 4π coverage and is capable of measuring exclusive reactions of the type A(e, e’pp). We will discuss the recent experimental results from JLab and future experiments planned at JLab as well as at JINR.

scholarly journals Metaform optics: Bridging nanophotonics and freeform optics

2021 ◽  
Vol 7 (18) ◽  
pp. eabe5112
Author(s):  
Daniel K. Nikolov ◽  
Aaron Bauer ◽  
Fei Cheng ◽  
Hitoshi Kato ◽  
A. Nick Vamivakas ◽  
...  
Keyword(s):  
Electron Beam ◽  
Electron Beam Lithography ◽  
Degrees Of Freedom ◽  
Optical Component ◽  
Optical Systems ◽  
Optical Surface ◽  
Lithography Process ◽  
Mobile Cameras ◽  
Freeform Optics ◽  
New Generation

The demand for high-resolution optical systems with a compact form factor, such as augmented reality displays, sensors, and mobile cameras, requires creating new optical component architectures. Advances in the design and fabrication of freeform optics and metasurfaces make them potential solutions to address the previous needs. Here, we introduce the concept of a metaform—an optical surface that integrates the combined benefits of a freeform optic and a metasurface into a single optical component. We experimentally realized a miniature imager using a metaform mirror. The mirror is fabricated via an enhanced electron beam lithography process on a freeform substrate. The design degrees of freedom enabled by a metaform will support a new generation of optical systems.

Some Issues of Repairing Manned Space Vehicles in Outer Space Using Electron Beam Welding

2021 ◽  
Vol 315 ◽  
pp. 101-105
Author(s):  
Leonid M. Lobanov ◽  
E.A. Asnis ◽  
Ye.G. Ternovy ◽  
Yu.V. Zubchenko ◽  
I.I. Statkevich ◽  
...  
Keyword(s):  
Electron Beam ◽  
Open Space ◽  
Electron Beam Welding ◽  
Outer Space ◽  
Beam Power ◽  
Space Vehicles ◽  
Automatic Mode ◽  
Manned Space ◽  
Robotic Devices ◽  
New Generation

A new generation of electron beam tool for welding during assembly and repair-restoration works on board of manned space vehicles in open space was demonstrated. The tool includes a small-sized electron beam gun (EBG) with an electron beam power of up to 2.5 kW and a high-voltage power source with a voltage of 10 kV. The design of the electron-optical system of EBG allows using it in both manual as well as in automatic mode applying robotic devices. Applying the manufactured EBG and manipulator, in vacuum chamber the works on simulating the repair of a spacecraft’s section of aluminum 2219 alloy were carried out. The obtained results of studying the structure and mechanical characteristics and also sealing of welds confirmed the high quality of welded joints and a reliability of the technology for repairing a damaged fragment of a spacecraft's body using electron beam welding.

scholarly journals XYZ states as hadronic molecules

2019 ◽  
Vol 202 ◽  
pp. 01002
Author(s):  
A.V. Nefediev
Keyword(s):  
Heavy Quarks ◽  
Exotic States ◽  
The Past ◽  
Quark Models ◽  
Molecule Model

In the past decade, a lot of new hadrons containing heavy quarks were discovered which do not fit into the scheme provided by the traditional quark models. Such states are known as the XYZ states and they are conventionally referred to as exotic ones. At present, there is no consensus on their nature, and different models and approaches have been suggested to explain their unusual properties. The talk is devoted to a brief overview of the molecule model for such exotic states.

scholarly journals The BmnRoot framework for experimental data processing in the BM@N experiment at NICA

2019 ◽  
Vol 214 ◽  
pp. 05027 ◽  
Author(s):  
Pavel Batyuk ◽  
Konstantin Gertsenberger ◽  
Sergey Merts ◽  
Oleg Rogachevsky
Keyword(s):  
Nuclear Physics ◽  
Nuclear Research ◽  
Information Support ◽  
Fixed Target ◽  
Experimental Data Processing ◽  
Multiparticle Interaction ◽  
Physics Program ◽  
Target Experiment ◽  
Under Construction ◽  
New Generation

A new generation of experiments for the relativistic nuclear physics is expected to be started up in the nearest years at the Nuclotron-based Ion Collider fAcility (NICA) under construction at the Joint Institute for Nuclear Research in Dubna. The main part of the facility is the essentially modernized accelerator Nuclotron. BM@N (Baryonic Matter at Nuclotron) is considered as a first stage towards realization of physics program available at NICA. It is a fixed target experiment aimed to work with the Nuclotron extracted beams of different species. The experiment had a set of technical runs since 2015. For a successful realization of the BM@N physics program, a well developed and tested software for simulation, digitization, reconstruction and analysis of collision events and other additional tasks is of utmost importance. The BmnRoot software developed in order to operate the mentioned tasks is described in this article. It includes modules for data digitizing obtained from BM@N detector systems, realistic simulation of signals in detectors, alignment of detectors, reconstruction of multiparticle interaction events, as well as all necessary systems for maintaining the databases of the experiment, visualization and providing information support for the experiment.

MASSIVE-QUARK BARYONS AS SKYRMIONS

1991 ◽  
Vol 06 (23) ◽  
pp. 2087-2100 ◽  
Author(s):  
MANNQUE RHO
Keyword(s):  
Degrees Of Freedom ◽  
Pivotal Role ◽  
Massive Scalar ◽  
Massive Quark ◽  
B Quarks ◽  
Quark Models

Massive-quark baryons containing one or more charm (c) or bottom (b) quarks are described as massive scalar doublet fields "wrapped" by the soliton of the light (up and down) flavors. The spin-isospin transmutation that takes place to make the trapped scalar behave like heavy-flavored quarks is analogous to what happens to a scalar doublet in the presence of a 't Hooft–Polyakov monopole. The Wess–Zumino term plays a pivotal role here. This model predicts spectra that resemble closely those of quark models. This feature is interpreted in terms of an induced gauge (or Berry) structure associated with "fast" and "slow" degrees of freedom corresponding, respectively, to the massive- and light-flavor quarks involved in the baryon structure.

scholarly journals Beam diagnostics on the electron beam welding installation at Budker Institute of Nuclear Physics

2020 ◽  
Vol 759 ◽  
pp. 012005 ◽  
Author(s):  
K A Blokhina ◽  
T A Devyataykina ◽  
A M Medvedev ◽  
Yu I Semenov ◽  
M M Sizov ◽  
...  
Keyword(s):  
Electron Beam ◽  
Nuclear Physics ◽  
Electron Beam Welding ◽  
Budker Institute ◽  
Beam Diagnostics

Significance of Considering Nonlinear Effects in Predicting the Dynamic Behavior of Rotating Machinery

1995 ◽  
Vol 1 (4) ◽  
pp. 431-458 ◽  
Author(s):  
Sherif T. Noah ◽  
Padmanabhan Sundararajan
Keyword(s):  
High Performance ◽  
Degrees Of Freedom ◽  
Nonlinear Behavior ◽  
Nonlinear Effects ◽  
Rotating Machinery ◽  
Modeling And Analysis ◽  
Rotor Systems ◽  
Rotor Support ◽  
Complex Phenomena ◽  
New Generation

Limitations of the currently practiced linearized analysis of industrial rotating machinery are dis cussed. An appreciation of these limitations is particularly significant for the development of new generation, high performance machinery in which new materials, rotor supports, coupling components, and sophisticated control systems will be used. In the absence of adequate familiarity and experience with the new systems, vari ous complex phenomena associated with their nonlinearities, which may lead to malfunction or catastrophic failure, could be missed altogether. A uniform approach to accurate modeling and analysis of rotor-support systems will therefore be essential. The present paper provides an exposition of recently published studies in nonlinear rotordynamics and their relevance to the design, analysis, and monitoring of rotating machinery. This includes a brief discussion of available analytical/computational methods and the various techniques proposed, which seek reducing the order of rotor systems with large number of degrees of freedom. In ad dition, new results on the nonlinear behavior of fluid-film bearings are presented herein to further emphasize the importance of nonlinear effects.

Sign in / Sign up

Export Citation Format

Share Document