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1.
A. Reiter P. S. Lumsden J. Ahrens J. R. M. Annand R. Beck J. C. McGeorge R. O. Owens 《The European Physical Journal A - Hadrons and Nuclei》2006,30(2):461-467
A 96-element plastic-scintillator detector array has been constructed to improve the energy resolution and tagged-photon flux
over a moveable energy range of up to 60MeV in the Glasgow photon tagging spectrometer at Mainz. Test results are presented
which demonstrate that this device improves the resolution by a factor of about 6 compared to the main detector array. It
is also shown that it is possible to achieve accurate energy calibration by using electron beams of several different accurately
known energies from the Mainz accelerator. 相似文献
2.
K. Vetter 《The European Physical Journal A - Hadrons and Nuclei》2002,15(1-2):265-269
Gamma-ray tracking in a closed array of highly segmented HPGe detectors is a new concept for the detection of γ-radiation.
Each of the interacting γ-rays is identified and separated by measuring the energies and positions of individual interactions
and by applying tracking algorithms to reconstruct the scattering sequences, even if many γ-rays hit the array at the same
time. The three-dimensional position and the energy of interactions are determined by using two-dimensionally segmented Ge
detectors along with pulse-shape analysis of the signals. Such a detector will have new and much improved capabilities compared
to current γ-ray spectrometer. One implementation of this concept, called GRETA (Gamma-Ray Energy Tracking Array), is currently
being under development at LBNL.
Received: 21 March 2002 / Accepted: 16 May 2002 / Published online: 31 October 2002
RID="a"
ID="a"e-mail: kvetter@lbl.gov 相似文献
3.
YU Wei-Lin 《中国物理C(英文版)》2010,34(9)
Generalized Parton Distributions(GPDs)provide a way to access total angular momenta of partons and give a multidimensional picture of the nucleon structure.Deeply Virtual Compton Scattering(DVCS)is the most direct exclusive process to study GPDs.Different azimuthal cross-section asymmetries with respect to beam helicity,beam charge,and target polarization have been measured in the HERMES experiment.A recoil detector was installed at HERMES to directly detect the recoil proton. 相似文献
4.
S. Yaschenko 《Physics of Particles and Nuclei》2014,45(1):173-175
The HERMES experiment at DESY, Hamburg, collected unique data on Deeply Virtual Compton Scattering (DVCS) utilizing the HERA polarized electron or positron beams with an energy of 27.6 GeV and longitudinally or transversely polarized or unpolarized gas targets (H, D or heavier nuclei). For the last two years of HERA running, a recoil detector was installed to improve the selection of DVCS events by direct measurement of the recoil protons. Recent HERMES results on DVCS off the hydrogen target and on associated processes ep → epπ0γ and ep → enπ+γ in the Δ-resonance region obtained with the recoil detector are presented. 相似文献
5.
I. Abt A. Caldwell K. Kröninger J. Liu X. Liu B. Majorovits 《The European Physical Journal A - Hadrons and Nuclei》2008,36(2):139-149
The GERmanium Detector Array (GERDA) is designed for the search for “neutrinoless double-beta decay” ( 0ν2β with germanium
detectors enriched in 76Ge . An 18-fold-segmented prototype detector for GERDA Phase II was exposed to an AmBe neutron source to improve the understanding
of neutron-induced backgrounds. Neutron interactions with the germanium isotopes themselves and in the surrounding materials
were studied. Segment information is used to identify neutron-induced peaks in the recorded energy spectra. The Geant4-based
simulation package MaGe is used to simulate the experiment. Though many photon peaks from germanium isotopes excited by neutrons
are correctly described by Geant4, some physics processes were identified as being incorrectly treated or even missing. 相似文献
6.
G. Poggi 《The European physical journal. Special topics》2007,150(1):369-372
The international FAZIA (Four π A and Z Identification
Array) Collaboration, presently involving researchers and institutions from France, Italy, Poland,
Romania, Spain, India, Canada and USA,
is currently investigating the use of new detector types/configurations (nTD Si
detectors, single chip telescope) and new electronics (charge/current preamplifiers,
digital sampling and signal processing) in view of defining a next-generation
detection array with improved particle identification capability to
study nuclear reaction dynamics and thermodynamics exploiting the Radioactive
Nuclear Beam (RNB) facilities. The present main R&D activities inside the Collaboration are
brielfly described. 相似文献
7.
A New Numerical Approach to Evaluate Variation of Electric Field Strength at the End of Particle Trajectory in Nuclear Track Detectors
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A geometrical model for an electrochemical etching (ECE) track in a dielectric detector is defined and a primaxy programme is written to generate the track. The generated track is transformed to an M× N matrix of primary voltages. Using a numerical method, the matrix of final voltages is computed, and using another numerical approach, the electric field strengths in the elements of detector volume are computed. The final field strength at the end of particle trajectory is obtained. The results of our numerical computation show that there are exact correlations between the field strength at the end of particle trajectory and the parameters of track under ECE. It is found that although two traditional models of Mason and Smythe in dielectrics can be partly applied for short and long tracks, none of them are able to explain the behaviour of field strength in a ‘general case'. Furthermore, we find that there is an expressive relationship between the field strength and the incidence angle of impacted particle, while the mentioned traditional models are not able to explain this effect. 相似文献
8.
Zhang Minglong Xia Yiben Wang Linjun Shen Hujiang Gu Beibei 《Solid State Communications》2004,130(8):551-555
The inherent properties of diamond can, in principle, make it an ideal material for radiation detectors with interesting capabilities. We have fabricated a particle detector using a free-standing CVD diamond film with a thickness of 300 μm and area of 2 cm×2 cm and measured 5.5 MeV α spectra from an 241Am source. The I-V characteristics indicate that a fine Ohmic contact is formed between the CVD diamond and electrode. At the external electric field 10 kV/cm, the collection efficiency reaches an average value of 41%, corresponding to a charge collection distance (CCD) of about 259 μm and the energy resolution achieves 4.3%. 相似文献
9.
D. Elia G. E. Bruno M. Caselle R. A. Fini V. Lenti V. Manzari V. Paticchio R. Santoro G. Anelli M. Burns I. A. Cali M. Campbell S. Ceresa P. Chochula J. Conrad S. Kapusta A. Kluge M. Morel P. Nilsson F. Osmic P. Riedler G. Stefanini C. Torcato de Matos F. Antinori R. Dima D. Fabris M. Lunardon S. Moretto A. Pepato F. Scarlassara G. Segato R. Turrisi G. Viesti A. Badalà F. Librizzi G. S. Pappalardo A. Pulvirenti F. Riggi M. Cinausero E. Fioretto G. Prete L. Vannucci M. Krivda L. Sándor F. Soramel T. Virgili 《Czechoslovak Journal of Physics》2005,55(12):1635-1638
The silicon pixel detector (SPD) comprises the two innermost layers of the inner tracking system oft he ALICE experiment at
LHC. Prototype SPD assemblies have been tested in high-energy proton and pion beams at the CERN SPS. The method used for data
analysis and the most relevant results in relation to detector performance are presented.
Presented in the Poster Session “Future Experiments and Facilities” at the 18th International Conference “Quark Matter 2005”,
Budapest, Hungary, 4–9 August 2005.
On behalf of the Silicon Pixel Detector project in the ALICE Collaboration 相似文献
10.
ABSTRACTIn this work, some ‘equivalent’ models for the simulation of efficiency response of a High-Purity Germanium (HPGe) detector, installed inside a ‘low background’ bunker in the Engineering Department of the University of Palermo, were developed. The main feature was to attribute the uncertainties of the model to only one of the parameters, the dead layer of the detector, keeping unchanged the other data provided by the manufacturer. With this technique, using the Monte Carlo PENELOPE code in the 2011 version, the efficiency response was evaluated and compared with the previous one performed with MCNP5 code.The validation of equivalent models is performed by comparing the simulation results with that of experimental spectrometric measurements of calibrated point sources and characterized volumetric sources such as a Marinelli beaker and an air filter reduced to a ‘packet-sample’.The use of equivalent models makes the evaluation of efficiency curves with a Monte Carlo code easier and faster, and requires only a few experimental values for validation. 相似文献
11.
I. Abt A. Caldwell K. Kröninger J. Liu X. Liu B. Majorovits 《The European Physical Journal C - Particles and Fields》2007,52(1):19-27
Experiments built to search for neutrinoless double beta-decay are limited in their sensitivity not only by the exposure but
also by the amount of background encountered. Radioactive isotopes in the surrounding of the detectors which emit gamma-radiation
are expected to be a significant source of background in the GERmanium Detector Array, GERDA. Methods to select electron induced
events and discriminate against photon induced events inside a germanium detector are presented in this paper. The methods
are based on the analysis of the time structure of the detector response. Data were taken with a segmented GERDA prototype
detector. It is shown that the analysis of the time response of the detector can be used to distinguish multiply scattered
photons from electrons.
PACS 23.40.-s; 14.60.Pq;29.40.-n 相似文献
12.
R. T. de Souza N. Le Neindre A. Pagano K. -H. Schmidt 《The European Physical Journal A - Hadrons and Nuclei》2006,30(1):275-291
This review on second- and third-generation multidetectors devoted to heavy-ion collisions aims to cover the last twenty years.
The presented list of devices is not exhaustive but regroups most of the techniques used during this period for nuclear reactions
at intermediate energy (≃ 10A MeV to 1A GeV), both for charged-particle and neutron detection. The main part will be devoted
to 4π multidetectors, projectile decay fragmentation, high-resolution magnetic spectrometers, auxiliary detectors and neutron
detection. The last part will present the progress in electronics and detection in view of the construction of future-generation
detectors. 相似文献
13.
J. Stewart 《The European Physical Journal A - Hadrons and Nuclei》2003,18(2-3):441-444
The HERMES experiment at DESY has measured the inclusive and semi-inclusive double-spin asymmetries of polarized positrons scattering from polarized hydrogen and deuterium targets in the kinematic range of Bjørken-x 0.023 < x < 0.06 and 1 GeV 2 < Q
2 < 10 GeV2. A RICH detector was installed for the deuterium running period and by providing the identification of charged pions and kaons has enabled the first measurement of charged kaon asymmetries. Based on the measured proton and deuterium asymmetries the polarized quark distributions have been extracted in leading-order pQCD.Received: 30 September 2002, Published online: 22 October 2003PACS:
13.60.Hb Total and inclusive cross-sections (including deep-inelastic processes) - 13.88. + e Polarization in interactions and scatteringJ. Stewart: For the HERMES Collaboration 相似文献
14.
Effect of Anode Floating Voltage and its Applications in Characterizing Silicon Drift Detectors
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Anode floating voltage is predicted and investigated for silicon drift detectors (SDDs) with an active area of 5 mm2 fabricated by a double-side parallel technology. It is demonstrated that the anode floating voltage increases with the increasing inner ring voltage, and is almost unchanged with the external ring voltage. The anode floating voltage will not be affected by the back electrode biased voltage until it reaches the full-depleted voltage (-50 V) of the SDD. Theoretical analysis and experimental results show that the anode floating voltage is equal to the sum of the inner ring voltage and the built-in potential between the p+ inner ring and the n+ anode. A fast checking method before detector encapsulation is proposed by employing the anode floating voltage along with checking the leakage current, potential distribution and drift properties. 相似文献
15.
H.V. Klapdor-Kleingrothaus Yu.G. Zdesenko 《The European Physical Journal A - Hadrons and Nuclei》1998,3(2):107-108
We suggest here the use of ice as shielding material in the large scale GENIUS experiment for the ultimate sensitive double
beta decay and dark matter search. The idea is to pack a working volume of several tons of liquid nitrogens, which contains
the “naked” Ge detectors, inside an ice shielding. Very thin plastic foil would be used in order to prevent leakage of the
liquid nitrogen. Due to the excellent advantages of ice shielding (high purity and low cost, self-supporting ability, thermo-isolation
and optical properties, safety) this could be another possible way of realization of the GENIUS project.
Received: 30 July 1998 相似文献
16.
We describe a detector for metastable rare gas atoms which allows the investigation of transverse atomic beam distributions
on the single atom level with lateral dimensions of 1 m, which occur frequently in the field of atom optics. In contrast to existing detection techniques, the conversion step from
the metastable atom to an electron is separated from the charge amplification to improve spatial resolution. The conversion
is performed at a metal surface, which is followed by an electron-optical system imaging the electron distribution with a
proper magnification onto a single electron detection unit. The spatial resolution that we achieve with this technique is
on the order of 1 m, the temporal resolution on the order of 1 s. The application of the detector for atom interferometry is discussed.
Received: 22 May 1996 / Revised version: 21 June 1996 相似文献
17.
Ondrej Chvala 《The European Physical Journal C - Particles and Fields》2009,62(1):211-216
PHENIX is a high rate experiment efficient at measuring rare processes, but has limited acceptance in azimuth and pseudorapidity (η). The Nose Cone Calorimeter (NCC), a W–Si sampling calorimeter in the region of 0.9<η<3, is one of the upgrades which will significantly increase coverage in both azimuth and pseudorapidity. The NCC will expand
PHENIX’s precision measurements of electromagnetic probes in η, reconstruct jets, perform a wide scope of correlation measurements, and enhance triggering capabilities. The detector will
significantly contribute to measurements of γ-jet correlations, quarkonia production, and low-x nuclear structure functions. This report discusses details of the detector design and its performance concerning a sample
of the physics topics which will benefit from the NCC. In view of recent funding difficulties, outlook of the activities is
discussed. 相似文献
18.
High spin states in70Ge nucleus have been studied in two different experiments using heavy ion fusion evaporation reaction. The Gamma Detector Array comprising of eight Compton-suppressed High Purity Ge detectors, was used in conjunction with a Recoil Mass Spectrometer — the HIRA — in order to identify and measure the transitions of this weakly populated nucleus. The level scheme is extended up to an excitation energy of13MeV for spin-parity 21- with several newly observed transitions placed in it. A rotational like band is also observed in this nucleus for the first time. 相似文献
19.
V. J. Bortolot 《Radiation measurements》2000,32(5-6):751-757
A new modular OSL system built on a 60-sample automation platform is described, upon which are installed a compatible family of sample elevator/heater mechanisms, OSL exciters, photon counting detectors, and irradiators. All components may be changed out, including the control electronics, firmware, and status display. The excitation family includes modules for both large area and arrays of single grains. The detector family has both single and quad (multispectral) capabilities. Both irradiation and detection stations are temperature controlled. 相似文献
20.
This article describes the new spectrometer setup for high-resolution Compton scattering experiments at BL08W, SPring-8. It employs an X-ray image intensifier (X-II) system as a position sensitive detector (PSD). The installation of the X-II system has improved the data-acquisition efficiency by 20 times compared to the previous quasi-PSD system. Compton profiles of CeRh3B2 have been measured with sufficient statistical accuracy, which indicates that the new setup can measure Compton profiles of virtually all materials within a reasonable beamtime. 相似文献