Download or read book Electron Induced Hypernuclear Spectroscopy Results in Hall A at Jefferson Lab written by and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The characteristics of the Jefferson LAB electron beam, together with those of the experimental equipments, offer a unique opportunity to study hypernuclear spectroscopy via electromagnetic induced reactions. Results are presented on 12C, 16O and 9Be targets. In the hypernuclear missing-mass spectrum the experiment achieves sub-MeV energy resolution by exploiting the characteristics of the High Resolution Spectrometer pair and the beam quality available at JLab. These studies have provided, among other things, the first quantitative information on core-excited states in hypernuclei, as well as the precise determination of Lambda binding energy in the Lambda16N hypernucleus. For the experiment on oxygen, a waterfall target has been employed, allowing simultaneous measurement of the elementary reaction on protons: a crucial measurement to disentangle the contribution of the elementary reaction from the measured hypernuclear production cross section, yielding direct access to the nucleus-hypernucleus transition structure.

Download or read book High Resolution Hypernuclear Spectroscopy at Jefferson Lab Hall A written by and published by . This book was released on 2013 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The characteristics of the Jefferson Lab electron beam, together with those of the experimental equipment, offer a unique opportunity to study hypernuclear spectroscopy via electromagnetic induced reactions. Experiment 94-107 started a systematic study on 1p-shell targets, $Ĉ$, ${̂9}Be$ and $Ô$. For $Ĉ$ for the first time measurable strength in the core-excited part of the spectrum between the ground state and the p state was shown in $_̂{\Lambda}B$ spectrum. A high-quality $_̂{\Lambda}N$ spectrum was produced for the first time with sub-MeV energy resolution. A very precise $\Lambda$ binding energy value for $_̂{\Lambda}N$, calibrated against the elementary $(e, e'K+̂)$ reaction on hydrogen, has also been obtained. ${̂9}_{\Lambda}Li$ spectrum shows some disagreement in strength for the second and third doublet with respect to the theory.

Download or read book Update of High Resolution e E K Hypernuclear Spectroscopy at Jefferson Lab s Hall A written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Updated results of the experiment E94-107 hypernuclear spectroscopy in Hall A of the Thomas Jefferson National Accelerator Facility (Jefferson Lab), are presented. The experiment provides high resolution spectra of excitation energy for 12B_\Lambda, 16N_\Lambda, and 9Li_\Lambda hypernuclei obtained by electroproduction of strangeness. A new theoretical calculation for 12B_\Lambda, final results for 16N_\Lambda, and discussion of the preliminary results of 9Li_\Lambda are reported.

Download or read book Recent Results on High Resolution Hypernuclear Spectroscopy by Electroproduction at Jefferson Lab Hall A written by G. Chang and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The first ''systematic'' study of 1 p shell hypernuclei with electromagnetic probes has started in Hall A at Jefferson Lab . The aim is to perform hypernuclear high resolution spectroscopy by the electroproduction of strangeness on four 1p-shell targets: 12C, 9Be, 16O, 7Li. The first part of the experiment on 12C and 9Be has been performed in 2004, the second part (16O and 7Li) is scheduled for June 2005. To overcome the major experimental difficulties, namely the low counting rate and the challenging Particle IDentification (PID), two septum magnets and a Ring Imaging CHerenkov (RICH) detector had to be added to the existing apparatus. After underlining the particular role the electroproduction reaction plays in hypernuclear physics we describe the challenging modifications of the Hall A apparatus. Preliminary results on 12C and 9Be are presented.

Download or read book Hypernuclear Spectroscopy with Electron Beam at JLab Hall C written by and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Hypernuclear spectroscopy with electron beam at JLab Hall C has been studied since 2000. The first experiment, JLab E89-009, used Short Orbit Spectrometer (SOS) as a kaon arm and a split-pole type spectrometer (ENGE) as an electron arm. E89-009 employed zero-degree tagging method, which tags scattered electrons at zero-degree and the kaon arm also covered zero-degree. This method obtains maximum yield of hypernuclei but sufferers from high rate background of electrons from bremsstrahlung and positrons from pair-creation. Nevertheless, this experiment demonstrated the possibility of the (e, e' K) reaction for hypernuclear spectroscopy by obtaining a hypernuclear mass spectrum with an energy resolution of better than 1 MeV (FWHM) [1][2]. However, poor signal to noise ratio and poor statistics requires us to improve the experimental setup. Therefore, E01-011 experiment was proposed based on the success of the JLab E01-011 experiment. Improvements of E01-011 from E09-009 can be summarized as: 1. Employed newly constructed high resolution kaon spectrometer (HKS) as a kaon arm. 2. Employed so-called 'tilt-method' for the electron arm. With the newly constructed HKS, having 2-10-4 momentum resolution, we expect an energy resolution of 400 keV (FWHM). The 'tilt-method' means the electron arm is tilted vertically to the splitter dispersive plane to avoid background electrons from bremsstrahlung and moeller scattering. The setup allowed us to use up to a few tens beam. The experiment was performed in 2005 and final result will be shown shortly. The third experiment, JLab E05-115 experiment was proposed as a natural extension of E01-011 experiment and will be performed in 2009. Improvements of experimental setup are, 1. Employed newly constructed high resolution electron spectrometer (HES) as a electron arm, 2. Employed a new charge-separation magnet (Splitter), fully customized for hypernuclear experiment at Hall C. With the third generation experimental setup, we can study variety of targets up to medium-heavy ones such as 52Cr. This talk mainly focuses on the current status of the E05-115 experiment.

Download or read book Experiments with the High Resolution Kaon Spectrometer at Jlab Hall C and the New Spectroscopy of 1 2 Lambda B Hypernuclei written by and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the pioneering experiment, E89-009 studying hypernuclear spectroscopy using the $(e, e{̂\prime}K+̂)$ reaction was completed, two additional experiments, E01-011 and E05-115, were performed at Jefferson Lab. These later experiments used a modified experimental design, the "Tilt Method", to dramatically suppress the large electromagnetic background, and allowed for a substantial increase in luminosity. Additionally, a new kaon spectrometer, HKS (E01-011), a new electron spectrometer, HES, and a new splitting magnet were added to produce precision, high-resolution hypernuclear spectroscopy. These two experiments, E01-011 and E05-115, resulted in two new data sets, producing sub-MeV energy resolution in the spectra of ${}{̂7}_{\Lambda}\text{He}$, ${}_̂{\Lambda}\text{B}$ and ${}{̂28}_{\Lambda} \text{Al}$ and ${}{̂7}_{\Lambda}\text{He}$, ${}_̂{\Lambda}\text{Be}$, ${}_̂{\Lambda}\text{B}$ and ${}{̂52}_{\Lambda}\text{V}$. All three experiments obtained a ${}_̂{\Lambda}\text{B}$, spectrum, which is the most characteristic $p$-shell hypernucleus and is commonly used for calibration. Independent analyses of these different experiments demonstrate excellent consistency and provide the clearest level structure to date of this hypernucleus as produced by the $(e, e{̂\prime}K+̂)$ reaction. This paper presents details of these experiments, and the extraction and analysis of the observed ${}_̂{\Lambda}\text{B}$ spectrum.

Download or read book Feasibility Test Run of C 12 e E K sup Reaction at Thomas Jefferson National Accelerator Facility written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The high quality and high duty factor (100%) electron beam at Jefferson Lab offers an opportunity to broaden their view of hypernuclear physics by studying the (e, e[prime]K[sup +]) reaction with high resolution. The present data represent a feasibility study of such a reaction on a carbon target. The test run was carried out during experiments E91-16 (Electroproduction of Kaons and Light Hypernuclei) and E93-18 (Kaon Electroproduction on p(e, e[prime]K[sup +])Y). These two experiments used liquid deuterium and hydrogen targets, respectively. There exist data on an aluminum target for the background calibration of the liquid targets which are suitable also for a feasibility study of electroproduction of hypernuclei. These data are still under analysis. The goal of this test run is to evaluate issues concerned with the electroproduction of hypernuclei. These issues include: (1) the quasi-free production rate, which had not been measured previously, (2) random coincidence background, (3) keon identification over a possibly large hadronic background, and (4) possible evaluation of the production rate of the bound hypernuclear structures. This test run will supply significant knowledge for running high quality hypernuclear experiments at Jefferson Lab. The spectroscopy of hypernuclei has been studied mainly in two ways: the strangeness-exchange reaction (K[sup -], [pi][sup -]), and associated strangeness production ([pi][sup +], K[sup +]). The (e, e[prime]K[sup +]) reaction has the advantage of exciting both natural- and unnatural-parity states and the possibility of obtaining good energy resolution. The cross section for the (e, e[prime]K[sup +]) reaction is about a hundred times smaller than for the corresponding hadronic production reactions but it is compensated for by the availability of high intensity and high duty factor electron beams. In order to optimize the production rate, the kinematic setting requires both the scattered electron and kaon to be detected at very forward angles. The test run was not optimized for hypernuclear production, but it serves as an important technical evaluation for future hypernuclear programs at Jefferson Lab. The first high-resolution spectroscopy experiment on p-shell lambda hypernuclei is tentatively scheduled to run in 1999 in Hall C at Jefferson Lab.

Download or read book 10th Conference on the Intersections of Particle and Nuclear Physics written by Marvin L. Marshak and published by American Institute of Physics. This book was released on 2010-01-11 with total page 1010 pages. Available in PDF, EPUB and Kindle. Book excerpt: CIPANP 2009 explores areas of common interest between nuclear physicists, high energy (particle) physicists and astrophysicists. These areas range from studies of the strong interactions that bind nuclei together to physics of the very early Universe and include such topics as neutrinos, hadron physics, spin physics, heavy ion physics, QCD and heavy flavor physics. The Conference papers include descriptions of searches for "new physics", phenomena that cannot be accounted for by current theories.

Download or read book Proceedings of The IX International Conference on Hypernuclear and Strange Particle Physics written by Josef Pochodzalla and published by Springer Science & Business Media. This book was released on 2008-06-27 with total page 400 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the proceedings of the IX International Conference on Hypernuclear and Strange Particle Physics (HYP 2006). This conference series is devoted to the progress of our knowledge about strangeness flavor in hadron and nuclear physics. Besides the traditional topics such as hadron structure, hypernuclear spectroscopy and weak decay of hypernuclei, a particular focus of this conference was on the properties of strange mesons and their binding in nuclear systems.

Download or read book Feasibility Test Run of C 12 e E K Reaction at Thomas Jefferson National Accelerator Facility written by and published by . This book was released on 1998 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Hypernuclear Spectroscopy with the e E prime K Reaction written by Yu Fujii and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental conditions of the (e, e'K+) reaction for hypernuclear spectroscopy at Jefferson Lab Hall C are considered. Then two hypernuclear experiments at Hall C, Jlab E89-009 and E01-011 are introduced and compared, and possibility to extract information on hypernuclear states are discussed by referring expected spectra obtained with a DWIA calculation.

Download or read book Hypernuclear Physics Programs Via Electroproduction in Hall C at Jefferson Lab written by and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Hypernuclei with strangeness -1 have been intensively studied both theoretically and experimentally using hadronic probes and reactions, (K, [pi]) and ([pi], K), for many years since the first discovery of such formation in the earlier nuclear emulsion and bubble chamber experiments. Many recent review papers exist on the status of hypernuclear physics, such as the recent one written by B.F. Gibson and Ed V. Hungerford in which one can find detailed discussion on all aspects of hypernuclear physics and more complete reference list. The unique feature of this field can be summarized, in general, into three categories: (1) Strong Interaction Involving Strangeness, (2) Weak Interaction with [Delta]S = -1, and (3) Medium Modifications. For strong interaction, it is commonly believed that a hyperon can be treated as an ''impurity'' to probe deep interior of the nuclear medium to explore fundamental issues such as the changes in size and shape due to the short range feature of YN interactions, limit of conventional nuclear model (shell or cluster) in solving for many body systems with new degree of freedom, spin dependent forces (spin-spin, spin-orbital, tensor), new symmetry and explicit QCD effect in nuclear media. Many of such issues are impossible or very difficult to be studied in the ordinary nuclear physics. The keys for success in this part of field includes good energy resolution and wide ranged spectroscopy. Until now, many important issues are still unresolved or remained to be resolved in more consistent and satisfactory fashion, such as spin dependent forces. This is due to luck of high quality experimental facilities. Recent experiments at KEK using ([pi][sup +], K[sup +]) reaction with a dedicated new SKS spectrometer have demonstrated the importance of improving the energy resolution. New structures were found as resolution improved only from 3 MeV to 2 MeV.

Download or read book Hypernuclear Spectroscopy Via e E K in JLab s Hall A written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Results are presented from a new experiment (E94-107) in Hall A of the Thomas Jefferson National Accelerator Facility (JLab) producing {12/Lambda} B, {16/Lambda}N, and {9/Lambda}Li using electroproduction, (e, e'K+). In the hypernuclear missing-mass spectrum the experiment achieves very good energy resolution (670 keV FWHM) by exploiting the characteristics of the High Resolution spectrometer pair and the exceptional beam quality available at JLab. The spectrometers were used with the addition an INFN provided pair of septum magnets to reach the desired small angles. Also, the Hall A standard complement of equipment was further augmented by the addition of a Ring Imaging Cherenkov detector (RICH) to achieve the best possible kaon identification.

Download or read book Hypernuclear Spectroscopy Using the e E K Reaction written by and published by . This book was released on 2006 with total page 44607 pages. Available in PDF, EPUB and Kindle. Book excerpt: A pioneering experiment in Lambda hypernuclear spectroscopy, undertaken at the Thomas Jefferson National Accelerator Facility (Jlab), was recently reported. The experiment used the high- precision, continuous electron beam at Jlab, and a special arrangement of spectrometer magnets to measure the spectrum from {nat}C and 7Li targets using the (e, e' K+)reaction. The 12B hypernuclear spectrum was previously published. This experiment is now reported in more detail, with improved results for the 12B hypernuclear spectrum. In addition, unpublished results of the 7He hypernuclear spectrum are also shown. This later spectrum indicates the need for a more detailed few-body calculation of the hypernucleus and the reaction process. The success of this experiment demonstrates that the (e, e'K+) reaction can be effectively used as a high resolution tool to study hypernuclear spectra, ant its use should be vigorously pursued.

Download or read book High Resolution Hypernuclear Spectroscopy written by F. Garibaldi and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Hypernuclear spectroscopy provides fundamental information for understanding the effective?-Nucleon interaction. Jefferson Laboratory experiment E94-107 was designed to perform high resolution hypernuclear spectroscopy by electroproduction of strangeness in four 1p-shell nuclei: 12C, 9Be, 16O, and 7Li. The first part of the experiment on 12C and 9Be has been performed in January and April-May 2004 in Hall A at Jefferson Lab. Significant modifications were made to the standard Hall A apparatus for this challenging experiment: two septum magnets and a RICH detector have been added to get reasonable counting rates and excellent particle identification, as required for the experiment. A description of the apparatus and the preliminary analysis results are presented here.

Download or read book Proceedings of the Sendai International Symposium written by Kazushige Maeda and published by World Scientific. This book was released on 2010 with total page 469 pages. Available in PDF, EPUB and Kindle. Book excerpt: Importance of strange quarks in hadrons, nuclei and dense matter / A.W. Thomas -- Overview of strangeness nuclear physics / A. Gal -- Experimental overview and challenge in strangeness nuclear physics / K. Imai -- Recent QCD results on the strange hadron systems / M. Oka -- Strangeness physics with CLAS / V.D. Burkert -- Progress and issues in the electromagnetic production of kaon on the nucleon / T. Mart -- Neutral kaon photoproduction at LNS, Tohoku University / M. Kaneta et al. for the NKS/NKS2 collaboration -- Photoproduction of the [symbol] resonance from the neutron / K.H. Hicks and D. Keller for the LEPS collaboration -- Photo- and electroproduction of kaons / P. Bydz̮ouský -- Strangeness pproduction at ELSA / V. Kleber for the CBELSA/TAB collaboration -- Low Q[symbol] kaon electroproduction / P. Markowitz and A. Acha for the JLab E94-107 and Hall A collaborations -- Results on strangeness production from HADES / A. Schmah for the HADES collaboration -- [symbol] photo-production on the deuteron at LNS, Tohoku University / T. Ishikawa -- Current status of the GO parity violation experiment carried out at Jefferson Laboratory / L. Bimbot for the GO collaboration -- Production and searches for cascade baryons with CLAS / E.S. Smith for the CLAS collaboration -- Nijmegen Baryon-Baryon interactions S = -1,-2 systems / Th. A. Rijken, M.M. Nagels and Y. Yamamoto -- Hyperon-nucleus systems in G-matrix approach / Y. Yamamoto -- [symbol]C(O[symbol]) and [symbol]O potentials derived from the SU[symbol] quark-model Baryon-Baryon interaction / Y. Fujiwara, M. Kohno and Y. Suzuki

Download or read book Experimental Study of Hypernuclei Electroproduction by High Precision Spectroscopy written by and published by . This book was released on 2009 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: Jlab experiment E01-011, carried out in 2005 in JLab Hall C, is the second generation of the hypernuclear spectroscopy experiments by the (e,e'K+) reaction. The (e,e'K+) reaction is complimentary to the associated production reactions (K-,?-), (?+,K+) since, due to a larger momentum transfer to a hyperon, excitations of both spin-non-flip and spin-flip states are possible. The experiment uses high quality and continuous primary electron beam to produce neutron rich hypernuclei on various targets by the electroproduction. The experimental setup consists of splitter magnet, high resolution kaon spectrometer (HKS) and electron spectrometer (Enge) implemented in new configuration, the so called 'Tilt Method'. Production data was taken on multiple targets: CH2, 6Li, 7Li, 9Be, 10B, 12C and 28Si. In present study the analysis of CH2, 12C and 28Si is presented. The elementary processes of p(e,e'K+)?/? from CH2 data were used for calibration of the spectrometer optics and kinematics. The hypernuclear spectra of 12?B was obtained with ground state resolution of 0.47 ± 0.07 MeV (FWHM), the best ever achieved. Feasibility of the electroproduction reaction to study medium to heavy targets has been proven with the first high resolution beyond p-shell hypernuclear spectra from 28?Al hypernuclei. The obtained results of the E01-011 experiment confirmed that hypernuclear spectroscopy by the (e,e'K+) reaction is a very useful technique.