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1.
The ISAC facility at TRIUMF utilizes up to 100 μA from the 500 MeV H- cyclotron to produce the RIB using the Isotopic Separation On Line (ISOL) method. The ISAC-I facility comprised the RNB production target stations, the mass separator and the beam delivery to low energy area and to a room temperature linear accelerator composed of a 4-rod RFQ and an inter-digital H type structure Drift Tube LINAC. ISAC-I linear accelerator can provide beam from A = 3 to 30 amu with an energy range from 0.15 to 1.5 A MeV. Since the beginning of operations target development program has been to increase proton beam currents on targets. Now we routinely operate our target at 50 to 85 μA and recently we have operated our target at 100 μA. Other developments are in place to add other ion sources, laser, FEBIAD and ECRIS to the actual surface ion source. The last two five year plans were mainly devoted to the construction of a heavy ion superconducting LINAC (ISAC-II), that will upgrade the mass and the energy range from 30 to 150 and 1.5 to 6.5 A MeV, respectively. We are now commissioning the medium β section and first experiment is scheduled for the fall 2006.  相似文献   

2.
B P Das 《Pramana》1998,50(6):515-519
The general features of parity nonconservation (PNC) in atoms arising from neutral weak currents and the nuclear anapole moment are discussed. The theoretical approaches used to calculate PNC observables are briefly mentioned. A brief review of the present status of atomic PNC is presented and its potential as a probe of physics beyond the standard model is highlighted.  相似文献   

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The present status of experiments seeking double-beta decay is surveyed. The results of the most sensitive experiments are discussed. Particular attention is given to describing the NEMO-3 detector, which is intended for seeking the neutrinoless double-beta decay of various isotopes (100Mo, 82Se, etc.) with a sensitivity as high as T 1/2 ~ 1025 yr, which corresponds to a sensitivity to the Majorana neutrino mass at a level of 0.1 to 0.3 eV. The first results obtained with the NEMO-3 detector are presented. A review of the existing projects of double-beta-decay experiments where it is planned to reach a sensitivity to the Majorana neutrino mass at a level of 0.01 to 0.1 eV is given.  相似文献   

5.
The transport of the time autocorrelation function in randomly inhomogeneous media with spatially separated static and dynamic regions is considered. Combining the photon mean trajectory method with the diffusing-wave spectroscopy technique, a method is proposed for fast reconstruction of images of dynamic inhomogeneities in a randomly inhomogeneous medium with a specified dynamics of scatterers, including media with Brownian diffusion and directional flows. The method of mean trajectories is complemented by Monte Carlo modeling, which makes it possible to apply this method to systems with a complex dynamics of scatters.  相似文献   

6.
As a result of a combination of an external cavity and modulation techniques, noise-immune cavity-enhanced optical heterodyne molecular spectroscopy (NICE-OHMS) is one of the most sensitive absorption techniques, capable of reaching close-to-shot-noise sensitivities, down to 5×10-13 fractional absorption at 1 s averaging. Due to its ability to provide sub-Doppler signals from weak molecular overtone transitions, the technique was first developed for frequency standard applications. It has since then also found use in fields of molecular spectroscopy of weak overtone transitions and trace gas detection. This paper describes the principles and the unique properties of NICE-OHMS. The historical background, the contributions of various groups, as well as the performance and present status of the technique are reviewed. Recent progress is highlighted and the future potential of the technique for trace species detection is discussed. PACS  33.80.-b; 07.57.-c; 42.62.Fi  相似文献   

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8.
Thomas McCauley 《Pramana》2006,67(4):681-689
I briefly review the present and future status of the burgeoning field of neutrino astronomy. I outline the astrophysics and particle physics goals, design, and performance of the various current and proposed neutrino telescopes. Also described are present results and future expectations.  相似文献   

9.
The present status of experimental approach to 100Sn in the spectroscopy of excited states is landmarked by the Tz=3/2 nuclei between 95Pd and 101In and the Tz=1 nuclei 94Pd and 98Cd. The detection limits with Pre-EUROBALL γ-arrays and ancillary detectors are below the 10?5 level of the total fusion- evaporation residue cross section. A large scale shell model analysis of the existing data reveals the shell structure at 100Sn, which shows a remarkable similarity to 56Ni. Evidence for an increasing proton-neutron interaction in approaching the N=Z line is deduced from high spin isomers and spherical yrast lines. The effective E2 operator for protons and neutrons and implications for a low lying particle-hole (ph) E2 excitation in 100Sn are discussed.  相似文献   

10.
Some results of investigations into a new nuclear-physics field associated with the production of radioactive nuclear beams and physical studies with these beams are presented. The most recent results obtained by studying the structure of nuclei and reaction mechanisms with radioactive nuclear beams are surveyed. Data obtained in Dubna at the DRIBs accelerator complex are presented along with allied results from other research centers. In this connection, existing experimental data on light loosely bound exotic nuclei are discussed. The parameters of DRIBs3, which is a new accelerator complex, are presented, and the physics research program that will be implemented with the aid of new setups, including a high-resolution magnetic analyzer (MAVR) and a 4π neutron detector (TETRA), is described. A collaboration in the realms of employing radioactive nuclear beams at the DRIBs complex together with other accelerator complexes [SPIRAL2 (France), RIKEN (Japan), FAIR (Germany), and RIBF (CIIIA)] on the basis of employing new highly efficient experimental facilities has already led to the discovery of new phenomena in nuclear physics and will make it possible to study in the future new regions of nuclear matter in extreme states.  相似文献   

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Euroball is a European project to build a highly efficient and powerful gamma-ray spectrometer for nuclear structure spectroscopy. The project is an amalgamation of recent technical advances in detectors, electronics and data acquisition. In the first phase the spectrometer consists of 30 large single crystal Ge detectors, 26 Clover Ge detectors and 15 Cluster Ge detectors each with an associated suppression shield. The 239 individual Ge detector elements will have a total photopeak efficiency ∈ p of ≈ 10% and will enable the properties of the atomic nucleus to be studied with a sensitivity up to or better than 10?5 of the production cross-section. The elements of the spectrometer, including the detectors, the electronics and the data acquisition system, some of the planned ancillary detectors and the first results will be presented. Several developments are under investigation for the upgrade of Euroball for its second phase. These include an inner BGO ball for multiplicity and summed energy determination and inner particle detectors for charged particle identification. These developments will also be discussed.  相似文献   

13.
超声处理有机废水的现状与进展   总被引:2,自引:1,他引:1       下载免费PDF全文
从超声降解有机废水的机理入手,对当前单频和多频(二维正交和三维)超声以及超声技术与其他技术联用降解污水的原理、影响因素和效果和国内外研究现状进行了总结和回顾,同时对该技术在处理有机废水方面的研究趋势进行了展望。  相似文献   

14.
The present status of double-beta-decay experiments (including the search for 2β +, ECβ +, and ECEC processes) are reviewed. The results of the most sensitive experiments are discussed. Average and recommended half-life values for two-neutrino double-beta decay are presented. Conservative upper limits on effective Majorana neutrino mass and the coupling constant of the Majoron to the neutrino are established as 〈m ν 〉 < 0.75 eV and 〈g ee 〉 < 1.9 × 10−4, respectively. Proposals for future double-betadecay experiments with a sensitivity for the 〈m ν 〉 at the level of 0.01–0.1 eV are considered.  相似文献   

15.
Muon diagnostics is a technique for the remote monitoring of various dynamic processes in the heliosphere and the Earth’s magnetosphere and atmosphere, based on analyzing spatial and angular variations in the flux of muons detected simultaneously from all directions in the upper hemisphere. Approaches to data analysis and some of the results of studies of the atmospheric and extra-atmospheric processes detected using the URAGAN muon hodoscope are discussed.  相似文献   

16.
A short review of spin physics program at JINR is presented. The proposals on spin program at the NICA collider are discussed. The main purpose of this program is to study the nucleon spin structure and other phenomena with polarized proton and deuteron beams.  相似文献   

17.
Abhay Deshpande 《Pramana》2003,61(5):859-864
In 2001–2002 the relativistic heavy-ion collider (RHIC) at the Brookhaven National Laboratory (BNL) was first commissioned for polarized proton collisions. Polarized protons were injected into the RHIC, accelerated to 100 GeV, stored and the two beams were made to collide in four interaction regions. I will review the progress made by the RHIC spin program, followed by the physics goals for the next few years. After that I will present a brief overview of a proposal to build a high intensity polarized electron/positron beam facility at BNL which would enable deep inelastic scattering (DIS) experiments to be pursued at BNL by its collisions with the RHIC hadron beams.  相似文献   

18.
Thomas Schwetz 《Pramana》2009,72(1):119-129
The status of neutrino oscillations from global data is summarized, with the focus on the three-flavour picture. The status of sterile neutrino oscillation interpretations of the LSND anomaly in the light of recent MiniBooNE results is also discussed. Furthermore, an outlook on the measurement of the mixing angle ϑ 13 in the near term future, as well as prospects to discover CP violation in neutrino oscillations and to determine the type of the neutrino mass ordering by long-baseline experiments in the long term future are given.   相似文献   

19.
Yang C  Wax A  Dasari RR  Feld MS 《Optics letters》2001,26(10):686-688
We report on phase-dispersion optical tomography, a new imaging technique based on phase measurements using low-coherence interferometry. The technique simultaneously probes the target with fundamental and second-harmonic light and interferometrically measures the relative phase shift of the backscattered light fields. This phase change can arise either from reflection at an interface within a sample or from bulk refraction. We show that this highly sensitive (~5 degrees ) phase technique can complement optical coherence tomography, which measures electric field amplitude, by revealing otherwise undetectable dispersive variations in the sample.  相似文献   

20.
Based on photon migration the new goal of diffuse optical imaging is to reveal optical contrasts in the depth of biological tissues. We discuss first the origin of contrast mechanism (absorption, fluorescence and scattering) used on diffuse optical imaging and spectroscopy. Then, various experimental approaches are described based on CW, pulsed and modulated light excitation and detection. Theoretical models which provide solutions for direct and inverse problems are presented using random walk theory. Finally two studies on breast imaging and on the use of fluorescence exogeneous markers are discussed in detail.  相似文献   

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