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Measurements of Separate Neutron and Gamma-Ray Coincidences with Liquid Scintillators and Digital PSD Technique

Description: A new technique is presented for the measurement of neutron and/or gamma-ray coincidences. Separate neutron neutron, neutron gamma-ray, gamma-ray neutron, and gamma-ray gamma-ray coincidences are acquired with liquid scintillation detectors and a digital pulse shape discrimination (PSD) technique based on standard charge integration method. The measurement technique allows for the collection of fast coincidences in a time window of the order of a few tens of nanoseconds between the coincident particles. The PSD allows for the acquisition of the coincidences in all particle combinations. The measurements are compared to results obtained with the MCNP-PoliMi code, which simulates neutron and gamma-ray coincidences from from a source on an event-by-event basis. This comparison leads to good qualitative agreement.
Date: October 1, 2007
Creator: Flaska, Marek & Pozzi, Sara A
Partner: UNT Libraries Government Documents Department

Neutrino Physics at Fermilab

Description: The Liquid Scintillator Neutrino Detector (LSND), located at the LANSCE (formerly LAMPF) linear accelerator at Los Alamos National Laboratory, has seen evidence for the oscillation of neutrinos, and hence neutrino mass. That discovery was the impetus for this LDRD project, begun in 1996. The goal of this project was to define the appropriate technologies to use in a follow up experiment and to set in place the requirements for such an experiment.
Date: July 9, 1999
Creator: Federspiel, F.; Garvey, G.; Louis, W.C.; Mills, G.B.; Tayloe, R.; Sandberg, V. et al.
Partner: UNT Libraries Government Documents Department

Characterization of Large Liquid Scintillation Detectors

Description: This report presents the results of the characterization of 11 large liquid scintillators. The neutron energy threshold and maximum detection efficiency were determined as a function of voltage and constant fraction discriminator threshold. Fits to the response of each detector were found. The results can be used to select the experimental settings in the operation of the detectors to ensure consistent response and repeatability.
Date: August 25, 2003
Creator: Pozzi, S.A.
Partner: UNT Libraries Government Documents Department

The NOvA experiment

Description: The NOvA Project will construct a 15 kt Far Detector 835 km from Fermilab at Ash River Minnesota, a 220 ton Near Detector on the Fermilab site and upgrade the existing NuMI beamline from 400 kW to 700 kW. The detector technology is liquid scintillator captured in reflective rigid PVC cells. The light is captured using WLS fibre and routed to avalanche photo diodes. NO?A is designed to observe the appearance of electron neutrinos, determine the value of sin{sup 2}(2{theta}{sub 13}) and begin the study of CP violation in the neutrino sector. NO?A is the only currently approved experiment with the ability to determine the neutrino mass ordering. The NOvA physics program and projected sensitivities are described in this report.
Date: January 1, 2008
Creator: Ray, Ronald E.
Partner: UNT Libraries Government Documents Department

The Design and Performance of a High Sensitivity Loss Monitor System for Use in the Fermilab Antiproton Rings

Description: As part of a general laboratory cleanup of hazardous materials from the accelerator enclosures they have replaced the liquid scintillator based paint can type beam loss monitors with improved loss monitors based on plastic scintillator. This paper describes the design of these counters and their performance in the PBAR source.
Date: January 1, 1994
Creator: Halling, Alfred Mike,; Zagel, James R.; Hahn, Alan & /Fermilab
Partner: UNT Libraries Government Documents Department

NEUTRINO OSCILLATION RESULTS FROM LSND

Description: The Liquid Scintillator Neutrino Detector took data during the years 1993 through 1998. The results of a final analysis of the data are reported here. In summary, the analysis resulted in a cleaner sample of decay-at-rest oscillation candidates and provided a strong constraint on beam related backgrounds. The oscillation probability is fitted to the correlated photon parameter in the inclusive electron sample. The fit yields an excess of 83.3 {+-} 21.2 events attributable to neutrino oscillations. This corresponds to an oscillation probability of (0.25 {+-} 0.06 {+-} 0.04)% for that detector and beam configuration.
Date: October 1, 2000
Creator: Mills, G.B.
Partner: UNT Libraries Government Documents Department

The KamLAND Full-Volume Calibration System

Description: We have successfully built and operated a source deployment system for the KamLAND detector. This system was used to position radioactive sources throughout the delicate 1-kton liquid scintillator volume, while meeting stringent material cleanliness, material compatibility, and safety requirements. The calibration data obtained with this device were used to fully characterize detector position and energy reconstruction biases. As a result, the uncertainty in the size of the detector fiducial volume was reduced by a factor of two. Prior to calibration with this system, the fiducial volume was the largest source of systematic uncertainty in measuring the number of antineutrinos detected by KamLAND. This paper describes the design, operation and performance of this unique calibration system.
Date: March 5, 2009
Creator: Collaboration, KamLAND; Berger, B. E.; Busenitz, J.; Classen, T.; Decowski, M. P.; Dwyer, D. A. et al.
Partner: UNT Libraries Government Documents Department

SCALED ELECTRON MODEL OF A DOGBONE MUON RLA WITH MULTI-PASS ARCS

Description: The design of a dogbone RLA with linear-field multi-pass arcs was earlier developed for accelerating muons in a Neutrino Factory and a Muon Collider. It allows for efficient use of expensive RF while the multi-pass arc design based on linear combined-function magnets exhibits a number of advantages over separate-arc or pulsed-arc designs. Such an RLA may have applications going beyond muon acceleration. This paper describes a possible straightforward test of this concept by scaling a GeV scale muon design for electrons. Scaling muon momenta by the muon-to-electron mass ratio leads to a scheme, in which a 4.5 MeV electron beam is injected at the middle of a 3 MeV/pass linac with two double-pass return arcs and is accelerated to 18 MeV in 4.5 passes. All spatial dimensions including the orbit distortion are scaled by a factor of 7.5, which arises from scaling the 200 MHz muon RF to a readily available at CEBAF 1.5 GHz. The footprint of a complete RLA fits in an area of 25 by 7 m. The scheme utilizes only fixed magnetic fields including injection and extraction. The hardware requirements are not very demanding, making it straightforward to implement. In this report, we have shown first of all that measuring the energy spectrum of the fast neutrons in the liquid scintillators allows one to distinguish the two chemical forms of plutonium. In addition, combining this information with the Feynman 2-neutron and 3-neutron correlations allows one to extract the {alpha}-ratio without explicitly knowing the multiplication. Given the {alpha}-ratio one can then extract the multiplication as well as the {sup 239}Pu and {sup 240}Pu masses directly from the moment equations.
Date: July 1, 2012
Creator: Kevin Beard, Rolland Johnson, Vasiliy Morozov, Yves Roblin, Andrew Hutton, Geoffrey Krafft, Slawomir Bogacz
Partner: UNT Libraries Government Documents Department

Intial performance from the NOvA surface prototype detector

Description: NOvA, the NuMI Off-Axis {nu}{sub e} Appearance experiment, will study {nu}{sub {mu}} {yields} {nu}{sub e} oscillations characterized by the mixing angle {Theta}{sub 13}. Provided {Theta}{sub 13} is large enough, NOvA may ultimately determine the ordering of the neutrino masses and measure CP violation in neutrino oscillations. A complementary pair of detectors will be constructed {approx}14 mrad off beam axis to optimize the energy profile of the neutrinos. This system consists of a surface based 14 kTon liquid scintillator tracking volume located 810 km from the main injector source (NuMI) in Ash River, Minnesota and a smaller underground 222 Ton near detector at the Fermilab. The first neutrino signals at the Ash River Site are expected prior to the 2012 accelerator shutdown. In the meantime, a near detector surface prototype has been completed and neutrinos from two Fermilab sources have been observed using the same highly segmented PVC and liquid scintillator detector system that will be deployed in the full scale experiment. Design and initial performance characteristics of this prototype system are being fed back into the design for the full NOvA program.
Date: September 1, 2011
Creator: Muether, M.
Partner: UNT Libraries Government Documents Department

Structural design of a high energy particle detector using liquid scintillator

Description: This thesis presents a design for a 10,000 ton liquid scintillator neutrino detector being considered for the MINOS project at Fermilab. Details of designing, manufacturing, and assembling the active detector components are presented. The detector consists of 1080 magnetized steel absorber planes alternating with 1080 active detector planes. Each active plane is made up of plastic extrusions divided into nearly 400 cells for positional resolution. Life tests on the plastic extrusions determine their feasibility for containing the scintillator. The extrusions are sealed at the bottom, filled with liquid scintillator, and have an optical fiber running the entire length of each cell. The fibers terminate at the top of each extrusion in a manifold. An optical-fiber-light-guide connects the fibers in each manifold to a photo-detector. The photo-detector converts the light signals from the scintillator and optical fibers into electrical impulses for computer analysis.
Date: February 1, 1997
Creator: Berg, Timothy John & U., /Minnesota
Partner: UNT Libraries Government Documents Department

Comparison Between Digital and Analog Pulse Shape Discrimination Techniques For Neutron and Gamma Ray Separation

Description: Recent advancement in digital signal processing (DSP) using fast processors and computer makes it possible to be used in pulse shape discrimination applications. In this study, we have investigated the feasibility of using a DSP to distinguish between the neutrons and gamma rays by the shape of their pulses in a liquid scintillator detector (BC501), and have investigated pulse shape-based techniques to improve the resolution performance of room-temperature cadmium zinc telluride (CZT) detectors. For the neutron/gamma discrimination, the advantage of using a DSP over the analog method is that in analog system two separate charge-sensitive ADC's are required. One ADC is used to integrate the beginning of the pulse risetime while the second ADC is for integrating the tail part. Using a DSP eliminates the need for separate ADCs as one can easily get the integration of two parts of the pulse from the digital waveforms. This work describes the performance of these DSP techniques and compares the results with the analog method.
Date: November 1, 2005
Creator: Aryaeinejad, R. & Hartwell, John K.
Partner: UNT Libraries Government Documents Department

Analysis of Neutron and Photon Detection Position for the Calibration of Plastic (BC-420) and Liquid (BC-501) Scintillators

Description: This report presents the results of the neutron and photon calibration of a Bicron BC-420 plastic scintillator and a BC-501 liquid scintillator using a set of reference gamma sources and a Cf-252 source. The position of neutron and photon detection inside the scintillators as a function of energy is investigated by Monte Carlo simulation.
Date: August 27, 2003
Creator: Pozzi, S.A.
Partner: UNT Libraries Government Documents Department

Measurement of Neutron Energy Spectra behind Shielding of a 120 GeV/c Hadron Facility

Description: Neutron energy spectra were measured behind the lateral shield of the CERF (CERN-EU High Energy Reference Field) facility at CERN with a 120 GeV/c positive hadron beam (mainly a mixture of protons and pions) on a cylindrical copper target (7-cm diameter by 50-cm long). NE213 organic liquid scintillator (12.7-cm diameter by 12.7-cm long) was located at various longitudinal positions behind shields of 80- and 160-cm thick concrete and 40-cm thick iron. Neutron energy spectra in the energy range between 12 MeV and 380 MeV were obtained by unfolding the measured pulse height spectra with the detector response functions which have been experimentally verified in the neutron energy range up to 380 MeV in separate experiments. The corresponding MARS15 Monte Carlo simulations generally gave good agreements with the experimental energy spectra.
Date: December 14, 2005
Creator: Nakao, N.; Rokni, S. H.; Vincke, H.; Khater, Hesham; Prinz, A. A.; Taniguchi, S. et al.
Partner: UNT Libraries Government Documents Department

Testing the wave packet approach to neutrino oscillations in future experiments

Description: When neutrinos propagate over long distances, the mass eigenstate components of a flavor eigenstate will become spatially separated due to their different group velocities. This can happen over terrestrial distance scales if the neutrino energy is of order MeV and if the neutrino is localized (in a quantum mechanical sense) to subatomic scales. For example, if the Heisenberg uncertainty in the neutrino position is below 10{sup -2} {angstrom}, neutrino decoherence can be observed in reactor neutrinos using a large liquid scintillator detector.
Date: May 1, 2010
Creator: Kayser, Boris; Kopp, Joachim & /Fermilab
Partner: UNT Libraries Government Documents Department

NOvA detector technology with intial performance from the surface prototype

Description: NOvA, the NuMI Off-Axis {nu}{sub e} Appearance experiment, will study {nu}{sub {mu}} {yields} {nu}{sub e} oscillations characterized by the mixing angle {Theta}{sub 13}. Provided {Theta}{sub 13} is large enough, NOvA may ultimately determine the ordering of the neutrino masses and measure CP violation in neutrino oscillations. A complementary pair of detectors will be constructed {approx}14 mrad off beam axis to optimize the energy profile of the neutrinos. This system consists of a surface based 14 kTon liquid scintillator tracking volume located 810 km from the main injector source (NuMI) in Ash River, Minnesota and a smaller underground 222 Ton near detector at the Fermilab. The first neutrino signals at the Ash River Site are expected prior to the 2012 accelerator shutdown. In the meantime, a near detector surface prototype has been completed and neutrinos from two Fermilab sources have been observed using the same highly segmented PVC and liquid scintillator detector system that will be deployed in the full scale experiment. Design and initial performance characteristics of this prototype system are being fed back into the design for the full NOvA program.
Date: September 1, 2011
Creator: Muether, M.
Partner: UNT Libraries Government Documents Department

SBIR Final Report. Liquid Core Optical Scintillating Fibers

Description: This Phase I SBIR project focused on developing flexible scintillating liquid core optical fibers, with potential uses in high-energy calorimetry, tracking, preradiators, active targets or other fast detectors. Progress on the six tasks of the project is summarized. The technical developments involve three technology components: (1) highly flexible capillaries or tubes of relatively low n (index of refraction) to serve as cladding and liquid core containment; (2) scintillator (and clear) fluids of relatively high n to serve as a core-- these fluids must have a high light transmission and, for some applications, radiation hardness; (3) optical end plugs, plug insertion, and plug-cladding tube sealing technology to contain the core fluids in the tubes, and to transmit the light.
Date: May 16, 2000
Creator: Beetz, C.P.; Steinbeck, J. & Buerstler, R.
Partner: UNT Libraries Government Documents Department

Properties of scintillator solutes

Description: This special report summarizes measurements of the spectroscopic and other properties of the solutes that were used in the preparation of several new liquid scintillators developed at EG and G/Energy Measurements/Santa Barbara Operations (the precursor to Bechtel Nevada/Special Technologies Laboratory) on the radiation-to-light converter program. The data on the individual compounds are presented in a form similar to that used by Prof. Isadore Berlman in his classic handbook of fluorescence spectra. The temporal properties and relative efficiencies of the new scintillators are presented in Table 1, and the efficiencies as a function of wavelength are presented graphically in Figure 1. In addition, there is a descriptive glossary of the abbreviations used herein. Figure 2 illustrates the basic structures of some of the compounds and of the four solvents reported in this summary. The emission spectra generally exhibit more structure than the absorption spectra, with the result that the peak emission wavelength for a given compound may lie several nm away from the wavelength, {lambda}{sub avg}, at the geometric center of the emission spectrum. Therefore, the author has chosen to list absorption peaks, {lambda}{sub max}, and emission {lambda}{sub avg} values in Figures 3--30, as being most illustrative of the differences between the compounds. The compounds, BHTP, BTPB, ADBT, and DPTPB were all developed on this program. P-terphenyl, PBD, and TPB are commercially available blue emitters. C-480 and the other longer-wavelength emitters are laser dyes available commercially from Exciton Corporation. 1 ref., 30 figs.
Date: June 1, 1998
Creator: Fluornoy, J.M.
Partner: UNT Libraries Government Documents Department

Separation and Analysis of Actinides by Extraction Chromotography Coupled with Alpha Liquid Scintillation Spectrometry

Description: This work describes the development and testing of a new method for the separation and analysis of most actinides of interest in environmental samples. It combines simplified extraction chromatography using highly selective absorption resins to partition the individual actinides with the measurement of their alpha activities by liquid scintillation spectrometry. The liquid scintillation counting technique pioneered by McDowell proved useful in determination of alpha emitting radionuclide in a wide variety of matrices. Alpha emitters are chemically extracted into an organic phase which also contains the scintillation cocktail. Oxygen is purged from the solution to improve the energy resolution of the measurement and the counting sample is sealed in a small glass tube for assay. The Photon-Electron Rejecting Alpha Liquid Scintillation (PERALS{trademark}) Spectrometer provides high counting efficiency, low background, pulse shape discrimination for photon/electron/{beta} particle rejection and moderate energy resolution in a compact package. Chemical extraction/liquid scintillation counting significantly reduces the extensive chemical purification and electroplating required for conventional alpha spectrometry with semiconductor detectors. PERALS{trademark} analyses have been used routinely for quickly surveying suspect samples and determining the source of unknown alpha activities.
Date: September 21, 1995
Creator: Cadieux, J.R. & Reboul, S.H.
Partner: UNT Libraries Government Documents Department

Internet access to data for scintillation compounds

Description: The LBL Pulsed X-Ray Facility has scintillation data on a large variety of inorganic scintillators. We offer this information on all compounds that we have tested. The only restrictions/favors that we ask users of this data are: (1) The data is intended for research use and may not be sold; (2) If any portion of the data is used in a publication, that the following text appear somewhere in the publication: {open_quotes}This work was supported in part by the Director, Office of Energy Research, Office of Health and Environmental Research, Medical Applications and Biophysical Research Division of the U.S. Department of Energy under contract No. DE-AC03-76SF00098, and in part by Public Health Service Grant No. R01 CA48002 awarded by the National Cancer Institutes, Department of Health and Human Services.{close_quotes}.
Date: September 1, 1995
Creator: Moses, W.W.; West, A.C. & Derenzo, S.E.
Partner: UNT Libraries Government Documents Department

WMAPping out Neutrino Masses

Description: Recent data from the Wilkinson Microwave Anisotropy Probe (WMAP) place important bounds on the neutrino sector. The precise determination of the baryon number in the universe puts a strong constraint on the number of relativistic species during Big-Bang Nucleosynthesis. WMAP data, when combined with the 2dF Galaxy Redshift Survey (2dFGRS), also directly constrain the absolute mass scale of neutrinos. These results impinge upon a neutrino oscillation interpretation of the result from the Liquid Scintillator Neutrino Detector (LSND).We also note that the Heidelberg-Moscow evidence for neutrinoless double beta decay is only consistent with the WMAP+2dFGRS data for the largest values of the nuclear matrix element.
Date: October 28, 2003
Creator: Pierce, Aaron & Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department

New liquid scintillators for fiber-optic applications

Description: New long-wavelength-emitting, high-speed, liquid scintillators have been developed and tailored specifically for plasma diagnostic experiments employing fiber optics. These scintillators offer significant advantages over commercially available plastic scintillators in terms of sensitivity and bandwidth. FWHM response times as fast as 350 ps have been measured. Emission spectra, time response data, and relative sensitivity information are presented.
Date: January 1, 1981
Creator: Lutz, S. S.; Franks, L. A.; Flournoy, J. M. & Lyons, P. B.
Partner: UNT Libraries Government Documents Department

New liquid scintillators for fiber-optic applications

Description: New long-wavelength-emitting, high-speed, liquid scintillators have been developed and tailored specifically for plasma diagnostic experiments employing fiber optics. These scintillators offer significant advantages over commercially available plastic scintillators in terms of sensitivity and bandwidth. FWHM response times as fast as 350 ps have been measured. Emission spectra, time response data, and relative sensitivity information are presented.
Date: January 1, 1981
Creator: Lutz, S.S.; Franks, L.A.; Flournoy, J.M. & Lyons, P.B.
Partner: UNT Libraries Government Documents Department

New scintillators for fiber optics: system sensitivity and bandwidth as a function of fiber length

Description: Long-wavelength liquid scintillators have been developed for fiber-optic plasma-diagnostic experiments. Relative system sensitivity and bandwidth data as a function of fiber length for several scintillator systems will be presented.
Date: January 1, 1981
Creator: Lutz, S.; Franks, L.A.; Flournoy, J.M. & Lyons, P.B.
Partner: UNT Libraries Government Documents Department

Probing Dark Energy via Neutrino and Supernova Observatories

Description: A novel method for extracting cosmological evolution parameters is proposed, using a probe other than light: future observations of the diffuse anti-neutrino flux emitted from core-collapse supernovae (SNe), combined with the SN rate extracted from future SN surveys. The relic SN neutrino differential flux can be extracted by using future neutrino detectors such as Gadolinium-enriched, megaton, water detectors or 100-kiloton detectors of liquid Argon or liquid scintillator. The core-collapse SN rate can be reconstructed from direct observation of SN explosions using future precision observatories. Our method, by itself, cannot compete with the accuracy of the optical-based measurements but may serve as an important consistency check as well as a source of complementary information. The proposal does not require construction of a dedicated experiment, but rather relies on future experiments proposed for other purposes.
Date: July 10, 2006
Creator: Hall, Lawrence; Hall, Lawrence J.; Murayama, Hitoshi; Papucci, Michele & Perez, Gilad
Partner: UNT Libraries Government Documents Department