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 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 In addition, unpublished results of the 7He hypernuclear spectrum are also shown.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 Precision Hypernuclear Spectroscopy Study by the e e K Reaction written by and published by . This book was released on 2002 with total page 269 pages. Available in PDF, EPUB and Kindle. Book excerpt: Jefferson Lab experiment E89009 is the first experiment to study hypernuclear spectroscopy by (e,e' K+) reaction. The 12 / LambdaB spectrum was observed from carbon target with the best energy resolution ever achieved from direct measurement of hypernuclear spectrum. The comparisons of the 12 / LambdaB spectrum with theoretical predictions were provided in terms of excitation strength and level separations. The overall excitation is in accord with theoretical calculations. The binding energies of p-shell and s-shell Lambda states were extracted. The photo-production cross section of the 12 / LambdaB ground state was also extracted. The experiment is also the pioneer in detecting scattered electrons at near zero degrees. The benefit and lessons learned from this method was also discussed.

Download or read book High Resolution Spectroscopy of the B 12 Lambda Hypernucleus Produced by the e E prime K Reaction written by and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: High energy CW electron beams at new accelerator facilities allow electromagnetic production and precision study of hypernuclear structure, and we report here on the first experiment demonstrating the usefulness of the (e, e'K+) reaction. This experiment is also the first to take advantage of the enhanced virtual photon flux available when electrons are scattered at approximately zero degrees. The observed resolution, ~900 keV, of the 12B(hypernuclear) spectrum is the best yet attained using magnetic spectrometers. The positions of the major excitations are in agreement with theoretical predictions and the previous binding energy measurements.

Download or read book Investigation of High precision Lambda Hypernuclear Spectroscopy Via the e E K Reaction written by and published by . This book was released on 2011 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of [Lambda] hypernuclear structure is very interesting in point of the understanding of the interaction between [Lambda] and nucleon ([Lambda]-N interaction) and its strange structure itself due to the containment of a [Lambda] hyperon which has a strangeness as a new degree of freedom. In the several way to study the Lamda hypernuclei, the (e, e'K+) reaction spectroscopy is a powerful tool for the precise investigation of [Lambda] hypernuclear structure. The purpose of the preset thesis is the establishment of the experimental design with the efficient data analysis method for the (e, e'K+) hypernuclear spectroscopic experiment in the wide mass region (from A=7 to A=52). It is very challenging to perform the (e, e'K+) spectroscopic experiment with such a heavy target, because of the huge electron background due to the bremsstrahlung process. In the experiment, it is required to obtain the necessary hypernuclear yield, suppressing the background event ratio. We achieved these requirements by newly constructing the high resolution electron spectrometer (HES) and splitter magnet (SPL) dedicated to the (e, e'K+) spectroscopic experiment. The HES consists of two quadrupole magnets and a dipole magnets (Q-Q-D) with a momentum resolution of dp/p = 3x10-4 at p = 0.84 GeV/c. It was used being vertically tilted by 6.5 degree so as to optimize signal to noise ratio and hypernuclear yield. The SPL is a dipole magnet. The experimental target was placed at the entrance of this magnet. The role of the SPL is to separate four kind of particles; scattered kaons, photons created by the bremsstrahlung, the post beam and scattered electrons. In addition, since the SPL is a part of the kaon and electron spectrometers. We designed the magnet shape carefully considering these points. The experiment was performed with 2.344 GeV/c electron beam from CEBAF at Jefferson Lab. The experimental setup consists of the HES, SPL and HKS (high momentum resolution kaon spectrometer). The HKS is also a Q-Q-D type spectrometer with the momentum resolution of dp/p = 2x10-4 at p = 1.2 GeV/c. In the data analysis, the particle momentum calibration was the most important procedure. At the initial point, the particle momentum was obtained from the calculated magnetic field map of the spectrometer whose accuracy is an order of 10-2. The initial momentum was calibrated by two step, the the magnetic field map improvement and the calibration with known masses of [Lambda]/[sigma]0 which were observed by the CH2 target data. As a result of the calibration, the momentum resolutions of HKS and HES were estimated as 4x10-4 and 6x10-4, respectively. Though these values are the double of the designed value, it was achieved to obtain the [Lambda]/[sigma]0 peaks with the same order of the designed energy from the original calculated magnetic field. The cross section was calculated with the several estimated factors. The averaged p([gamma]*, K+)[Lambda] cross section in the HKS acceptance, (0.90

Download or read book Hypernuclear Spectroscopy with the Pi K Reaction written by and published by . This book was released on 1990 with total page 5 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 High Pressure Hypernuclear Spectroscopy Study by the E E K Reaction written by Lulin Yuan and published by . This book was released on 2002 with total page 488 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Spectroscopy of 28Al Lambda 12B Lambda 7He Lambda by the e E K Reaction 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 by the $(e, e^{\prime}K^+)$ reaction is one of the powerful tools to investigate precise structures of hypernuclei and to study $\Lambda$N interaction. The second generation hypernuclear experiment at JLab Hall C(E01-011) was successfully performed in 2005, introducing the two novel experimental configurations, High resolution and large acceptance Kaon Spectrometer(HKS) and Tilt method. Thanks to these new configurations, various hypernuclei such as $^{28}_{\Lambda}$Al, $^{12}_{\Lambda}$B and $^{7}_{\Lambda}$He were measured with precise energy resolution of 500 keV (FWHM). Obtained absolute binding energies and cross sections were compared with other experimental data and recent theoretical calculations based on shell model and cluster model. The results of this study provided new information on $\Lambda$N interaction.

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 High Resolution Spectroscopic Study of math mmultiscripts mi Be mi mprescripts mi Mathvariant written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Spectroscopy of a $^_{\Lambda}$Be hypernucleus was carried out at JLab Hall C using the $(e, e^{\prime}K^{+})$ reaction. A new magnetic spectrometer system (SPL+HES+HKS), specifically designed for high resolution hypernuclear spectroscopy, was used to obtain an energy spectrum with a resolution of 0.78 MeV (FWHM). The well-calibrated spectrometer system of the present experiment using the $p(e, e^{\prime}K^{+})\Lambda, \Sigma^{0}$ reactions allowed us to determine the energy levels, and the binding energy of the ground state peak (mixture of 1$^{-}$ and 2$^{-}$ states) was obtained to be B$_{\Lambda}$=8.55$\pm$0.07(stat.)$\pm$0.11(sys.) MeV. Furthermore, the result indicates that the ground state energy is shallower than that of an emulsion study by about 0.5 MeV which provides valuable experimental information on charge symmetry breaking effect in the $\Lambda N$ interaction.

Download or read book Hypernuclear Spectroscopy Program at JLab Hall C written by and published by . This book was released on 2008 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt: DOI: http://dx.doi.org/10.1016/j.nuclphysa.2008.01.029 Hypernuclear production by the (e, e?K+) reaction has unique advantages in hypernuclear spectroscopy of the S=?1 regime. The second-generation spectroscopy experiment on 12C, 7Li and 28Si targets has been recently carried out at JLab Hall C with a new experimental configuration (Tilt method) and also using a new high-resolution kaon spectrometer (HKS). The experiment is described and preliminary results are presented together with the empasis of significance of the (e, e?K+) reaction for? hypernuclear spectroscopy and its future prospects.

Download or read book First Experiment on Spectroscopy of Lambda Hypernuclei by Electroproduction at Jlab written by and published by . This book was released on 2001 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The first experiment in Lambda-hypernuclear spectroscopy using the high precision electron beam at Jefferson laboratory (Jlab) has been carried out. The hypernuclear spectrometer system (HNSS) was used to measure spectra from the 12C(e, e(prime)K)12{sub {Lambda}}B reaction with sub-1 MeV resolution, the best energy resolution obtained thus far in hypernuclear spectroscopy with magnetic spectrometers. This paper describes the HNSS and the preliminary results for the 12{sub {Lambda}}B system. The experimental spectrum is consistent with the expected strong spin-flip excitations of unnatural parity states. A program of hypernuclear physics experiments is planned for the future with much higher yield and even better energy resolution.

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 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 The Second Generation Hypernuclear Spectroscopy at JLab Hall C E01 011 Experiment written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The second generation [Lambda] hypernuclear spectroscopy by (e, e'K) reaction has been carried out successfully at JLab in 2005. New configurations, HKS and Tilt method, significantly improved both energy resolution and statistics. Systematic error depend on tuning procedure was estimated by the blind analysis. Analysis is in the final stage. Third generation experiment (JLab E05-115) will be performed in the summer of 2009 w/ new e' spectrometer (HES).

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.