Download or read book Status of the Jefferson Lab Polarized Beam Physics Program and Preparations for Upcoming Parity Experiments written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: An ambitious nuclear physics research program continues at Jefferson Lab with Users at three experiment halls receiving reliable, highly polarized electrons at currents to 100 [micro]A. The polarized photoguns and drive lasers that contribute to Jefferson Lab's success will be described as well as significant events since PES2000. Typical of conditions at accelerators worldwide, success brings new challenges. Beam quality specifications continue to become more demanding as Users conduct more challenging experiments. In the months that follow this workshop, two parity violation experiments will begin at Jefferson Lab, G0 and HAPPEx2. The photogun requirements for these experiments will be discussed as well as our plans to eliminate/minimize systematic errors. Recent efforts to construct high power Ti-Sapphire drive lasers for these experiments also will be discussed.
Download or read book SPIN 2002 written by Yousef I. Makdisi and published by American Institute of Physics. This book was released on 2003-09-04 with total page 1198 pages. Available in PDF, EPUB and Kindle. Book excerpt: The SPIN 2002 Proceedings describe the recent advances in the field of spin physics. The topics cover research in high energy and nuclear physics and the study of the nuclear spin structure. The symposium also covers advances in polarized proton and electron acceleration and storage as well as polarized ion sources and targets. The first measurement of spin physics observables in pp collisions at center of mass energy of 200 Gev was announced at this symposium.
Download or read book High Intensity Polarized Electron Sources written by and published by . This book was released on 2008 with total page 2201 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the 1990s, at numerous facilities world wide, extensive R & D devoted to constructing reliable GaAs photoguns helped ensure successful accelerator-based nuclear and high-energy physics programs using spin polarized electron beams. Today, polarized electron source technology is considered mature, with most GaAs photoguns meeting accelerator and experiment beam specifications in a relatively trouble-free manner. Proposals for new collider facilities however, require electron beams with parameters beyond today's state-of-the-art and serve to renew interest in conducting polarized electron source R & D. And at CEBAF/Jefferson Lab, there is an immediate pressing need to prepare for new experiments that require considerably more beam current than before. One experiment in particular?Q-weak, a parity violation experiment that will look for physics beyond the Standard Model?requires 180 uA average current at polarization>80% for a duration of one year, with run-averaged helicity correlate.
Download or read book Precision M ller Polarimetry and Applications at Jefferson Laboratory written by William Patrick Henry and published by . This book was released on 2019 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt: Jefferson Lab's cutting-edge parity-violating electron scattering program has increasingly stringent requirements for systematic errors. Beam polarimetry is often one of the dominant systematic errors in these experiments. A new Moeller Polarimeter in Hall A of Jefferson Lab (JLab) was installed in 2015 and has taken first measurements for a polarized scattering experiment. Upcoming parity violation experiments in Hall A include CREX, PREX-II, MOLLER and SOLID with the latter two requiring
Download or read book Jefferson Lab Science written by and published by . This book was released on 2015 with total page 6 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Continuous Electron Beam Accelerator Facility (CEBAF) and associated experimental equipment at Jefferson Lab comprise a unique facility for experimental nuclear physics. Furthermore, this facility is presently being upgraded, which will enable a new experimental program with substantial discovery potential to address important topics in nuclear, hadronic, and electroweak physics. Further in the future, it is envisioned that the Laboratory will evolve into an electron-ion colliding beam facility.
Download or read book Jefferson Lab Science Past and Future written by and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Continuous Electron Beam Accelerator Facility (CEBAF) and associated experimental equipment at Jefferson Lab comprise a unique facility for experimental nuclear physics. This facility is presently being upgraded, which will enable a new experimental program with substantial discovery potential to address important topics in nuclear, hadronic, and electroweak physics. Further in the future, it is envisioned that the Laboratory will evolve into an electron-ion colliding beam facility.
Download or read book Achieving Beam Quality Requirements for Parity Experiments at Jefferson Lab written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurement of asymmetry between alternating opposite electron polarization in electron-nucleon scattering experiments can answer important questions about nucleon structures. Such experiments impose stringent condition on the electron beam quality, and thus the accelerator used for beam creation and delivery. Of particular concern to such ''parity'' experiments is the level of correlation between beam characteristics (orbit, intensity) and electron polarization that can obscure the real asymmetry. This can be introduced at the beam forming stage, created due to scraping, or not damped to desired level due to defective transport. Suppression of such correlation thus demands tight control of the beam line from cathode to target, and requires multi-disciplined approach with collaboration among nuclear physicists and accelerator physicists/engineers. The approach adopted at Jefferson Lab includes reduction of correlation source, improving low energy beam handling, and monitoring and correcting global transport. This paper will discuss methods adopted to meet the performance criteria imposed by parity experiments, and ongoing research aimed at going beyond current performance.
Download or read book PSTP 2007 written by Ahovi Kponou and published by American Institute of Physics. This book was released on 2008-02-25 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: Upton, New York, 10-14 September 2007
Download or read book Physics with CLAS at Jefferson Lab written by Michel Garcon and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The CLAS collaboration at Jefferson Lab is engaged in a wide range of experiments, covering mostly meson and baryon spectroscopy, nucleon structure through elastic and deep inelastic scattering, nuclear transparency and nucleon correlations in nuclei. These experiments use the CEBAF highly polarized electron beam, or the secondary tagged photon beam, together with the CLAS detector (CEBAF Large Acceptance Spectrometer), to which specific experiments bring additional equipment. In this talk, examples of recent results on subjects mentioned hereabove will be given, with special emphasis on nucleon structure. A short description of the planned upgrade from CLAS to CLAS12 is presented.
Download or read book CLAS FROST written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A large part of the experimental program in Hall B of the Jefferson Lab is dedicated to baryon spectroscopy. Photoproduction experiments are essential part of this program. CEBAF Large Acceptance Spectrometer (CLAS) and availability of circularly and linearly polarized tagged photon beams provide unique conditions for this type of experiments. Recent addition of the Frozen Spin Target (FROST) gives a remarkable opportunity to measure double and triple polarization observables for different pseudo-scalar meson photoproduction processes. For the first time, a complete or nearly complete experiment becomes possible and will allow model independent extraction of the reaction amplitude. An overview of the experiment and its current status is presented.
Download or read book Exciting Physics With New Accelerator Facilities Proceedings Of The International Workshop written by Hiroshi Toki and published by World Scientific. This book was released on 1998-10-07 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume discusses the exciting physics with new accelerator facilities, which are being constructed or proposed in various places. The facilities are RHIC (Brookhaven), CEBAF (TJINP), SPring-8 (Nishi-Harima), RIBF (RIKEN), JHP (KEK-INS), RIB (MSU), LISS (IUCF) and COSY (Juelich). RHIC aims at the creation of a QCD deconfinement phase and the study of the properties of such matter. CEBAF and SPring-8 use leptons to probe the quark-gluon structures of hadrons and nuclei. LISS and COSY use high resolution hadron beams to study hadron structures. JHP produces strong secondary hadron beams for hyper-nuclear physics and rare decay studies of basic symmetries. RIBF and RIB produce radioactive nuclear beams for the study of the nuclear structure of unstable nuclei far from beta stability, and astrophysics issues.
Download or read book Recovery Act Measurement of Parity Violation in Deep Inelastic Scattering and Studies of the Nucleon Spin Structure at JLab 6 and 11 GeV written by and published by . This book was released on 2016 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: The program proposed contains two ingredients which aim to address aspects of two of the three research frontiers of nuclear science as identified in the 2007 NSAC Long Range Plan. The first topic, a test of the current Standard Model, is an ongoing project focusing on measurements of the parity-violating asymmetry in ~e-2H deep inelastic scattering (PVDIS). The PVDIS measurement is complementary to other completed or ongoing low- to medium-energy tests of the Standard Model. As the first, exploratory step, an experiment using a 6 GeV electron beam will be carried out from October to December 2009 at the Thomas Jefferson National Accelerator Facility (JLab). Meanwhile, a program using the upgraded JLab 11 GeV beam is being planned. The PVDIS program as a whole will provide the first precision data on the axial quark neutral-weak coupling constants. This will either put the current Standard Model to a test that has never been done before, or reveal information on where to look for New Physics beyond the current Standard Model. The PVDIS program will also provide results on hadronic physics effects such as charge symmetry violation. The second part of the proposed program uses spin observables to address the research frontier concerning QCD and structure of the nucleon. An experiment using the JLab 6 GeV beam in 2001 showed that, contrary to predictions from perturbative quantum chromodynamics (pQCD), while the valence up quark's spin is parallel to the nucleon's spin, the valence down quark's spin is not. In order to test the limit of QCD in describing the nucleon spin structure to a region beyond the 6 GeV kinematics, this measurement will be extended to a more energetic, "deeper" valence quark region using the upgraded JLab 11 GeV beam with a polarized 3He target. Although the two topics of the proposed program appear to focus on different physics, for the upgraded JLab 11 GeV beam, both will utilize a new, yet-to-be-built large acceptance spectrometer, called "SoLID". Once built, SoLID can be used for other topics such as using PVDIS on a proton target to measure the valence quark distributions, using PVDIS on a polarized target to measure new electro-weak interference structure functions of the nucleon, and semi-inclusive deep inelastic scattering experiments. SoLID will greatly enhance the exploration potential of JLab. The proposed program will first focus on completion of the 6 GeV PVDIS experiment, its data analysis and publishing physics results. This 6 GeV experiment will explore whether precision PVDIS measurements are feasible, will set limits on the hadronic physics effects, and will improve our knowledge on the quark neutral weak couplings, optimally by a factor of six. Starting early 2010, efforts will be spent on preparation for the 11 GeV program, focusing on simulations of SoLID, optimization and construction of the SoLID detector package, and studies of the polarized 3He target and its improvements. Funding support for the whole program is requested here.
Download or read book Unfolding the Matter of Nuclei written by Società italiana di fisica and published by IOS Press. This book was released on 1998 with total page 544 pages. Available in PDF, EPUB and Kindle. Book excerpt: The nucleus and its constituents are a challenging problem. The lectures collected in this book present a broad and comprehensive review of the current knowledge about nuclei.They cover topics such as searching for signatures of the quarks in nuclei with electromagnetic probes and, at much higher energies, for signatures of the quark-gluon plasma in ultrarelativistic nuclear collisions. The attempts to obtain new nuclei in the laboratory are also discussed, as well as the central role played by nuclear physics in the development of weak interactions. Progress in all these areas rests on a deeper theoretical handling of the nuclear and nucleon’s structure. The latter can also be addressed by relying on numerical solutions of QCD on a discrete space-time lattice. The advancement of computational capabilities has spurred a growing interest in this approach. Finally, the book deals with different paths toward solving non-perturbative QCD.
Download or read book CERN Courier written by European Organization for Nuclear Research and published by . This book was released on 2000 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: This journal is devoted to the latest research on physics, publishing articles on everything from elementary particle behavior to black holes and the history of the universe.
Download or read book Spin Physics written by Donald G. Crabb and published by American Inst. of Physics. This book was released on 2009-08-25 with total page 1236 pages. Available in PDF, EPUB and Kindle. Book excerpt: The topics covered in the conference ranged from the physics that can be done with polarized beams of particles (protons, electrons, gamma-rays, etc.) to the techniques and instrumentation necessary to achieve this. Topics included: nucleon structure measurements (from where does the spin of the proton and neutron come), the acceleration, storage and polarization of particle beams and the polarized targets and sources necessary for mounting the experiments.
Download or read book An Assessment of U S Based Electron Ion Collider Science written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2018-10-13 with total page 153 pages. Available in PDF, EPUB and Kindle. Book excerpt: Understanding of protons and neutrons, or "nucleons"â€"the building blocks of atomic nucleiâ€"has advanced dramatically, both theoretically and experimentally, in the past half century. A central goal of modern nuclear physics is to understand the structure of the proton and neutron directly from the dynamics of their quarks and gluons governed by the theory of their interactions, quantum chromodynamics (QCD), and how nuclear interactions between protons and neutrons emerge from these dynamics. With deeper understanding of the quark-gluon structure of matter, scientists are poised to reach a deeper picture of these building blocks, and atomic nuclei themselves, as collective many-body systems with new emergent behavior. The development of a U.S. domestic electron-ion collider (EIC) facility has the potential to answer questions that are central to completing an understanding of atoms and integral to the agenda of nuclear physics today. This study assesses the merits and significance of the science that could be addressed by an EIC, and its importance to nuclear physics in particular and to the physical sciences in general. It evaluates the significance of the science that would be enabled by the construction of an EIC, its benefits to U.S. leadership in nuclear physics, and the benefits to other fields of science of a U.S.-based EIC.
