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1.
《Physics of Atomic Nuclei》2006,69(12):2083-2089
CUORICINO is an array of 62 TeO2 bolometers with a total mass of 40.7 kg (11.2 kg of 130Te), operated at about 10 mK to search for ββ(0ν) of 130Te. The detectors are organized as a 14-story tower and intended as a slightly modified version of one of the 19 towers of the CUORE project, a proposed tightly packed array of 988 TeO2 bolometers (741 kg of total mass of TeO2) for ultralow-background searches on neutrinoless double-beta decay, cold dark matter, solar axions, and rare nuclear decays. Started in April 2003 at the Laboratori Nazionali del Gran Sasso (LNGS), CUORICINO data taking was stopped in November 2003 to repair the readout wiring system of the 62 bolometers. Restarted in spring 2004, CUORICINO is presently the most sensitive running experiment on neutrinoless double-beta decay. No evidence for ββ(0ν) decay has been found so far and a new lower limit, T 1 2/0ν ≥ 1.8 × 1024 yr (90% C.L.), is set, corresponding to 〈m ν〉 ≤ 0.2–1.1 eV, depending on the theoretical nuclear matrix elements used in the analysis. Detector performance, operational procedures, and background analysis results are reviewed. The expected performance and sensitivity of CUORE is also discussed. CUORE Collaboration The text was submitted by the authors in English.  相似文献   

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CUORE is a proposed tightly packed array of 1000 TeO2 bolometers, each being a cube 5 cm on a side with a mass of 750 g. The array consists of 25 vertical towers, arranged in a square of 5 towers by 5 towers, each containing ten layers of four crystals. The design of the detector is optimized for ultralow-background searches for neutrinoless double beta decay of 130Te (33.8% abundance), cold dark matter, solar axions, and rare nuclear decays. A preliminary experiment involving 20 crystals of various sizes (MIBETA) has been completed, and a single CUORE tower is being constructed as a smaller scale experiment called CUORICINO. The expected performance and sensitivity, based on Monte Carlo simulations and extrapolations of present results, are reported.  相似文献   

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The ITER project     
ITER (the International Thermonuclear Experimental Reactor) is an international collaborative project aimed at demonstrating the scientific and technological feasibility of fusion energy for peaceful purposes. It is the next step for the magnetic fusion development programs of the four participants-the European Union, Japan, Russia, and the United States. This paper reports progress of the engineering design activities (EDA) for ITER. ITER's position in the four parties' fusion programs is outlined, the main elements of the design are introduced, and progress is summarized in physics and technology R&D that support the design activities. The outlook for the future is reviewed, particularly the desirability of making timely progress toward construction of ITER  相似文献   

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The Radioactive Beam Experiment REX-ISOLDE [1–3] is a pilot experiment at ISOLDE (CERN) testing the new concept of post acceleration of radioactive ion beams by using charge breeding of the ions in a high charge state ion source and the efficient acceleration of the highly charged ions in a short LINAC using modern ion accelerator structures. In order to prepare the ions for the experiments singly charged radioactive ions from the on-line mass separator ISOLDE will be cooled and bunched in a Penning trap, charge bred in an electron beam ion source (EBIS) and finally accelerated in the LINAC. The LINAC consists of a radiofrequency quadrupole (RFQ) accelerator, which accelerates the ions up to 0.3 MeV/u, an interdigital H-type (IH) structure with a final energy between 1.1 and 1.2 MeV/u and three seven gap resonators, which allow the variation of the final energy. With an energy of the radioactive beams between 0.8 MeV/u and 2.2 MeV/u a wide range of experiments in the field of nuclear spectroscopy, astrophysics and solid state physics will be addressed by REX-ISOLDE. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

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The ZFITTER project is aimed at the computation of high-precision theoretical predictions for various observables in high-energy electron-positron annihilation and other processes. The stages of the project development are described. Accent is made on applications to the analysis of LEP data. The present status of the project and perspectives are given as well.  相似文献   

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Neutrinoless double-beta decay (ββ(0ν)) is the most sensitive process in the search for leptonic number violation and its discovery would prove that the neutrino is a Majorana particle. From the experience of the NEMO-3 detector construction and data analysis, the NEMO Collaboration proposes a three-year R&D program in order to design a detector (SuperNEMO) sensitive to a ββ(0ν) period of few 1026 yr coupling track reconstruction and calorimeter. on behalf of the NEMO Collaboration The text was submitted by the author in English.  相似文献   

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A Facco 《Pramana》2001,57(2-3):623-637
The Project SPES (study and production of exotic nuclei) aims at the full design of a facility based on a 100 MeV, 1–30 mA CW proton Linac used for production of fission fragments from a uranium like target by means of a neutron converter. Neutron rich ion species are extracted, selected, further ionized at high charge state, isotopically purified and then accelerated through a superconducting Linac at energies up to 20 MeV/A. SPES represents INFN’s effort in view of the construction of the European next generation ISOL-type facility, which is expected to be operative by 2010. A conceptual design report of such a European facility is being prepared with the support of the European Commission. R&D activities, covering the most critical parts of the facility, have been partially started in the last two years, triggered by the French-Italian feasibility study of an accelerator driven system for waste transmutation. On behalf of the SPES Collaboration  相似文献   

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Eight monolingual Japanese listeners were trained to identify English /r/ and /l/ by using 560 training tokens produced by ten talkers in three positions (200 word initial, 200 consonant cluster, and 160 intervocalic tokens). Their baseline performance and transfer of learning were measured using 200 word initial and 200 consonant cluster tokens produced by additional ten talkers. Long-term training (15 days) with feedback indeed increased sensitivity to the nontraining tokens, but tremendous individual differences were found in terms of initial and final sensitivity and response bias. Even after training, however, there remained some tokens for each subject that were misidentified at a level significantly below chance, suggesting that truly nativelike identification of /r/ and /l/ may never be achieved by adult Japanese learners of English.  相似文献   

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A model explaining the thermoluminescence (TL) in CdF2: Eu is presented. We show that the energy barriers resulting from lattice relaxation govern the electron release and capture processes responsible for TL.  相似文献   

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We review work, done mainly at the author’s laboratory, on the spin gap which is the NMR manifestation of the pseudogap observed in the normal state of high-temperature superconductors. The relation of the spin gap to an electronic crossover in YBa2Cu4O8 is discussed. A possible explanation of both effects by assuming a charge density wave transition is presented. This suggestion is supported by measuring the isotope dependence of the spin gap in YBa2Cu4O8.  相似文献   

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In this paper we study the transient diffusion-limited A+B0, A0 = B0 annihilation via deterministic reaction-diffusion equations and via simulation of the stochastic many-particle problem. We show that the two approaches are not equivalent and that the deterministic expressions capture only part of the picture. A lower bound is derived for the density decay which indicates that the overall density follows the power law t–x with = mm(d/4, 1). Hierarchical oscillations superimposed on the power-law decay are observed for reactions on Sierpinski gaskets.This work is dedicated to Prof. George H. Weiss.  相似文献   

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The next-generation Facility for Low energy Antiproton and Ion Research (FLAIR) at GSI is going to be a dedicated research facility for ion research in the keV range. These ion beams will allow to explore fundamental properties in matter-antimatter research at ultra-low energies of only 20 keV/q in hitherto impossible experiments. To provide these very low energy beams, the Ultra-low energy Storage Ring (USR), an electrostatic synchrotron, will play a major role within the FLAIR complex. It combines the electrostatic storage mode with deceleration from an initial energy of 300 keV/q down to 20 keV/q—as well as an efficient beam cooling. To fulfill its role as a multi-purpose experimental facility, the design of the USR has not only to cover in-ring experiments, but needs to include a highly flexible beam extraction for serving different external experiments as well.  相似文献   

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The DYNAMAP project (Dynamic Acoustic Mapping – Development of low cost sensors networks for real time noise mapping) is a LIFE project aiming at developing a dynamic noise mapping system able to detect and represent in real time the acoustic impact due to road infrastructures. Scope of the project is the European Directive 2002/49/EC relating to the assessment and management of environmental noise (END).  相似文献   

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Physics of Atomic Nuclei - The ANTARES project aims to build a deep underwater Cherenkov neutrino telescope in the Mediterranean Sea. Currently the experiment is in the construction phase and has...  相似文献   

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Ablative laser propulsion (ALP) could revolutionize space travel by reducing the 30:1 propellant/payload ratio needed for near-earth orbit 50-fold. Experiments to date have demonstrated the necessary efficiency, coupling coefficient, and specific impulse for application, but were performed at pulse energies and spot sizes much smaller than required and at wavelengths not usable in the atmosphere. Prior experiments have also not simultaneously measured the properties of the ions produced or of the ablated surface, properties that would allow full understanding of the propulsion properties in terms of ion characteristics.

The first realistic measurements of laser propulsion parameters are proposed using PALS (Prague Asterix Laser System), the important parameters of which (pulse energy (~ 1 kJ), pulse length (400 ps), beam diameter (~ 29 cm), and flat beam profile) equal those required for application. The PALS wavelength is a little short (1.3 μ m vs.>1.5 μ m) but is closer than any other laser available and PALS’ 2ω/3ω capability should allow extrapolation to application values. The PALS’ proven infrastructure for measuring laser-driven ion properties means that only a ballistic pendulum for measuring momentum transfer will have to be added.  相似文献   

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