Search results for " Detection"
showing 10 items of 1676 documents
Time-of-flight telescope for heavy-ion RBS
2007
Abstract This paper describes a time-of-flight (TOF) spectrometer for Heavy-Ion Rutherford Backscattering Spectrometry (HI-RBS) recently installed at IMEC for thin film analysis. The TOF telescope allows the use of ion beams heavier than He, with advantages in terms of depth and mass resolution and sensitivity compared to conventional RBS based on planar Si detectors. The start timing-signal is produced by the secondary electrons emitted from a thin C foil when traversed by a backscattered ion; the electrons are deflected in an electrostatic mirror towards a Micro-channel plate (MCP) assembly which provides a fast timing response. The stop signal is obtained directly from a second MCP assem…
The BLAST experiment
2009
The Bates large acceptance spectrometer toroid (BLAST) experiment was operated at the MIT-Bates Linear Accelerator Center from 2003 until 2005. The detector and experimental program were designed to study, in a systematic manner, the spin-dependent electromagnetic interaction in few-nucleon systems. As such the data will provide improved measurements for neutron, proton, and deuteron form factors. The data will also allow details of the reaction mechanism, such as the role of final state interactions, pion production, and resonances to be studied. The experiment used: a longitudinally polarized electron beam stored in the South Hall Storage Ring; a highly polarized, isotopically pure, inter…
First microscopic evaluation of spin-dependent WIMP-nucleus scattering off 183W
2021
We perform the first consistent calculation of elastic-scattering and inelastic-scattering structure functions for spin-dependent WIMP-nucleus scattering for 183W in a microscopic nuclear-theory framework. The nuclear structure calculations are performed in the microscopic interacting boson-fermion model (IBFM-2). Our results show that while 183W is very insensitive to spin-dependent elastic scattering, the structure function for inelastic scattering is quite sizable at small momentum transfers. Moreover, to our knowledge 183W provides the first studied case where inelastic scattering can compete with elastic scattering as the primary detection signal. peerReviewed
First search for extremely high energy cosmogenic neutrinos with the IceCube Neutrino Observatory.
2010
We report on the results of the search for extremely-high energy (EHE) neutrinos with energies above $10^7$ GeV obtained with the partially ($\sim$30%) constructed IceCube in 2007. From the absence of signal events in the sample of 242.1 days of effective livetime, we derive a 90% C.L. model independent differential upper limit based on the number of signal events per energy decade at $E^2 \phi_{\nu_e+\nu_\mu+\nu_\tau}\simeq 1.4 \times 10^{-6}$ GeV cm$^{-2}$ sec$^{-1}$ sr$^{-1}$ for neutrinos in the energy range from $3\times10^7$ to $3\times10^9$ GeV.
Artificial neural networks for neutron/ γ discrimination in the neutron detectors of NEDA
2020
Three different Artificial Neural Network architectures have been applied to perform neutron/? discrimination in NEDA based on waveform and time-of-flight information. Using the coincident ?-rays from AGATA, we have been able to measure and compare on real data the performances of the Artificial Neural Networks as classifiers. While the general performances are quite similar for the data set we used, differences, in particular related to the computing times, have been highlighted. One of the Artificial Neural Network architecture has also been found more robust to time misalignment of the waveforms. Such a feature is of great interest for online processing of waveforms. Narodowe Centrum Nau…
Advancing Radiation-Detected Resonance Ionization towards Heavier Elements and More Exotic Nuclides
2022
Atoms 10(2), 41 (2022). doi:10.3390/atoms10020041
Ion source and low energy beam transport prototyping for a single-ended heavy ion ToF-ERDA facility
2023
We present the status of the ion source and low energy beam transport prototyping activities for a heavy ion time-of-flight elastic recoil detection analysis (ToF-ERDA) equipment, designed to accelerate a flux of 1–10 particle nano-Ampere of 40Ar6-12+ ions to 3–6 MeV energy for depth profiling of light elements. The prototype injector consists of a novel permanent magnet electron cyclotron resonance ion source CUBE-ECRIS with a minimum-B quadrupole field topology, and a 90° permanent magnet dipole with adjustable field strength for charge state selection. We report experimentally measured argon beam currents as a function of the applied microwave power and ion source potential to demonstrat…
Experimental Assessment of a Flat Sandwich-Like Self-Powered Detector for Nuclear Measurements in ITER Test Blanket Modules
2018
Neutron and gamma flux measurements in designated positions in the test blanket modules (TBMs) of ITER will be important tasks during its campaigns. Investigations on self-powered detectors (SPDs), a class of reactor flux monitors are undertaken in the framework of an ongoing project on development of nuclear instrumentation for European ITER TBMs. This paper reports the findings of experiments performed with an SPD in flat sandwich-like geometry. A detector with vanadium emitter is chosen for preliminary studies. Its irradiation in a thermal neutron field gives a proof of the principle of flat SPDs. It is further irradiated in the mixed neutron-gamma field of a 14-MeV neutron generator and…
A Method for Measurements of the Total 2H(γ,π−)PP Cross Sections at Threshold
1979
In recent years measurements of the total cross section for the reactions 2H(γ,π+ nn) and 2H(γ,π0)2H close to the production threshold were performed1. For the 2H(γ,π−)pp reaction data of similar good quality doesn’t exist. In this paper a method is prescribed and the feasibility for the reaction 2H(γ,π−)pp is demonstrated. Figure 1 shows the principle: The photon beam hits a liquid or high pressured gas target of 2H. π− are created on the deuteron and stopped in the same target cell. The major part of the tt are captured π− are captured by deuterons via the reaction 2H(π−,n)n. The energy is shared equally by the two neutrons (En= 68.2 MeV). One of these monochromatic neutrons is detected b…
Two-neutron removal reactions for very neutron-rich nuclei
1992
Abstract The two-neutron removal reactions of beams of 11 Li, 14 Be and 8 He upon Be, Ni and Au targets were studied at 30 MeV/u. The cross sections and the neutron forward angular distributions were measured; they correlate strongly with the two-neutron separation energy of the projectile. Even though the coverage of the neutron detectors was limited, a rough neutron-neutron distribution could be extracted. A simplified interpretation of the data is presented.