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Test and characterization of a new triple-GEM detector

Burns, Laurie Davenport
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 84 p.
ENG
Relevância na Pesquisa
45.51%
In my thesis project, I provide a description of the entire process of materials preparation, assembly, testing, and characterization of several triple-GEM (Gas-Electron Multiplier) prototype detectors. GEM detectors represent one of the latest developments in a new style of gaseous particle detectors. They have become well-known and widely used. Improvements in foil production are important for future applications of the detectors to large scale tracking devices. One function of this thesis project is to compare the performances of GEM foils produced by different sources when installed in identical prototype triple-GEM detectors.; by Laurie Davenport Burns.; Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Physics, 2006.; Includes bibliographical references (p. 83-84).

Development of techniques for quantum-enhanced laser-interferometric gravitational-wave detectors

Goda, Keisuke
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 225 p.
ENG
Relevância na Pesquisa
45.53%
A detailed theoretical and experimental study of techniques necessary for quantum-enhanced laser- interferometric gravitational wave (GW) detectors was carried out. The basic theory of GWs and laser-interferometric GW detectors, quantum noise in GW detectors, the theory of squeezed states including generation, degradation, detection, and control of squeezed states using sub-threshold optical parametric oscillators (OPOs) and homodyne detectors, experimental characterization of these techniques (using periodically poled KTiOPO4 in an OPO at 1064 nm for the first time), key requirements for quantum-enhanced GW detectors, and the propagation of a squeezed state in a complex interferometer and its interaction with the interferometer field were studied. Finally, the experimental demonstration of quantum-enhancement in a prototype GW detector was performed. By injecting a squeezed vacuum field of 9.3 dB (inferred) or 7.4 ± 0.1 dB (measured) at frequencies above 3 kHz and a cutoff frequency for squeezing at 700 Hz into the antisymmetric port of the prototype GW detector in a signal-recycled Michelson interferometer configuration, the shot noise floor of the detector was reduced broadband from 7.0 x 10-7 m/viH- to 5.0 x 10-17 m/V/H while the strength of a simulated GW signal was retained...

Calibration System Design and Determination of Filter Calibration Requirements for SNAP

Mostek, Nick
Fonte: [Bloomington, Ind.] : Indiana University Publicador: [Bloomington, Ind.] : Indiana University
Tipo: Doctoral Dissertation
EN
Relevância na Pesquisa
55.28%
Thesis (PhD) - Indiana University, Astronomy, 2007; The SuperNova/Acceleration Probe (SNAP) is a proposed space-based, wide-field telescope designed to measure the properties of dark energy in our universe. SNAP will measure ~2000 type Ia supernovae, and the reduction of systematic errors in the relative spectrophotometric measurements will be critical to the mission science. A stringent systematic error requirement of 2% in color photometry is driving the SNAP calibration methodology and system design into new areas of space-based, radiometric calibration for astronomical missions. At the forefront of these new calibration techniques is the use of narrowband light and photodiodes to measure the precise irradiance incident on SNAP filters and detectors. Using these techniques, I have built the Monochromatic Illumination and Cryogenic Calibration System (MICCS) to address the SNAP calibration hardware requirements. With this system, I can transfer the NIST irradiance calibration of an InGaAs photodiode to transfer photodiodes operated at 140K as well as measure the transmission of interference filters at incident angles and temperature similar to that used on the SNAP focal plane. Due to size and light efficiency constraints...

Characterization of large area photomultipliers and its application to dark matter search with noble liquid detectors

Bueno Villar, Antonio; Lozano Bah??lo, Julio; Melgarejo-Fern??ndez, Antonio Jes??s; Mu??oz, F. J.; Navarro, J. L.; Navas, Sergio; Ruiz, A. G.
Fonte: Institute of Physics Publicador: Institute of Physics
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
45.45%
There is growing interest in the use of noble liquid detectors to study particle properties and search for new phenomena. In particular, they are extremely suitable for performing direct searches for dark matter. In this kind of experiments, the light produced after an interaction within the sensitive volume is usually read-out by photomultipliers. The need to go to masses in the tonne scale to explore deeper regions of the parameter space, calls for the use of large area photomultipliers. In this paper we address the need to perform laboratory calibration measurements of these large photomultipliers, in particular to characterize its behaviour at cryogenic temperatures where no reference from the manufacturer is available. We present comparative tests of phototubes from two companies. The tests are performed in conditions similar to those of operation in a real experiment. Measurements of the most relevant phototube parameters (quantum efficiency, gain, linearity, etc.) both at room and liquid Argon temperatures are reported. The results show that the studied phototubes comply with the stringent requirements posed by current dark matter searches performed with noble-liquid detectors.

Alternate configurations for blocked impurity band detectors

Garcia, Jonathan C.
Fonte: Monterey California. Naval Postgraduate School Publicador: Monterey California. Naval Postgraduate School
Tipo: Tese de Doutorado Formato: xiv, 47 p. : ill. (some col.) ;
Relevância na Pesquisa
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Approved for public release; distribution in unlimited.; Silicon Blocked Impurity Band (BIB) detectors are highly efficient, radiation-hardened photodetectors that operate in the range of 5-40 æm. To further extend BIB coverage to 40-350 æm, Ge and GaAs BIB detectors are under development; however, these new detectors face fabrication issues that have delayed their introduction. This thesis will describe the use of a numerical model to examine alternate operating modes for GaAs BIB detectors in order to bypass current fabrication issues. The numerical simulations provide an understanding of the fundamental physics that governs detector transport. The proposed alternatives to standard operation are created by reversing the detector's bias and varying the blocking layer thickness. Modeling indicates that reversing the bias on these detectors provides a larger signal current than standard configurations, while preserving the principal benefits gained from a multilayered device. At the same time, the alternate bias configuration allows for the use of thicker blocking layers, while preserving overall detector responsivity and reducing shot noise. This proposed new model of operation should allow for the relaxation of fabrication constraints without sacrificing the inherent benefits associated with BIB detectors. These devices are of potential interest for missile defense and terahertz surveillance applications.; Lieutenant Commander...

Statistical Issues in Searches for New Physics

Lyons, Louis
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 05/09/2014
Relevância na Pesquisa
55.36%
Given the cost, both financial and even more importantly in terms of human effort, in building High Energy Physics accelerators and detectors and running them, it is important to use good statistical techniques in analysing data. Some of the statistical issues that arise in searches for New Physics are discussed briefly. They include topics such as: Should we insist on the 5 sigma criterion for discovery claims? The probability of A, given B, is not the same as the probability of B, given A. The meaning of p-values. What is Wilks Theorem and when does it not apply? How should we deal with the `Look Elsewhere Effect'? Dealing with systematics such as background parametrisation. Coverage: What is it and does my method have the correct coverage? The use of p0 versus p1 plots.; Comment: This is the write-up for the Proceedings of a talk delivered at the LHCP2014 Conference at Columbia University, New York in June 2014no diagrams 5 pages long,

Scientific and Technological Development of Hadrontherapy

Braccini, Saverio
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 06/01/2010
Relevância na Pesquisa
45.44%
Hadrontherapy is a novel technique of cancer radiation therapy which employs beams of charged hadrons, protons and carbon ions in particular. Due to their physical and radiobiological properties, they allow one to obtain a more conformal treatment with respect to photons used in conventional radiation therapy, sparing better the healthy tissues located in proximity of the tumour and allowing a higher control of the disease. Hadrontherapy is the direct application of research in high energy physics, making use of specifically conceived particle accelerators and detectors. Protons can be considered today a very important tool in clinical practice due to the several hospital-based centres in operation and to the continuously increasing number of facilities proposed worldwide. Very promising results have been obtained with carbon ion beams, especially in the treatment of specific radio resistant tumours. To optimize the use of charged hadron beams in cancer therapy, a continuous technological challenge is leading to the conception and to the development of innovative methods and instruments. The present status of hadrontherapy is reviewed together with the future scientific and technological perspectives of this discipline.; Comment: Presented at the 11th ICATPP Conference on Astroparticle...

Waveguide single-photon detectors for integrated quantum photonic circuits

Sprengers, J. P.; Gaggero, A.; Sahin, D.; Nejad, S. Jahanmiri; Mattioli, F.; Leoni, R.; Beetz, J.; Lermer, M.; Kamp, M.; Höfling, S.; Sanjines, R.; Fiore, A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 25/08/2011
Relevância na Pesquisa
45.45%
The generation, manipulation and detection of quantum bits (qubits) encoded on single photons is at the heart of quantum communication and optical quantum information processing. The combination of single-photon sources, passive optical circuits and single-photon detectors enables quantum repeaters and qubit amplifiers, and also forms the basis of all-optical quantum gates and of linear-optics quantum computing. However, the monolithic integration of sources, waveguides and detectors on the same chip, as needed for scaling to meaningful number of qubits, is very challenging, and previous work on quantum photonic circuits has used external sources and detectors. Here we propose an approach to a fully-integrated quantum photonic circuit on a semiconductor chip, and demonstrate a key component of such circuit, a waveguide single-photon detector. Our detectors, based on superconducting nanowires on GaAs ridge waveguides, provide high efficiency (20%) at telecom wavelengths, high timing accuracy (60 ps), response time in the ns range, and are fully compatible with the integration of single-photon sources, passive networks and modulators.; Comment: 11 pages, 4 figures

Entanglement-based continuous-variable quantum key distribution with multimode states and detectors

Usenko, Vladyslav C.; Ruppert, Laszlo; Filip, Radim
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/12/2014
Relevância na Pesquisa
55.45%
Secure quantum key distribution with multimode Gaussian entangled states and multimode homodyne detectors is proposed. In general the multimode character of both the sources of entanglement and the homodyne detectors can cause a security break even for a perfect channel when trusted parties are unaware of the detection structure. Taking into account the multimode structure and potential leakage of information from a homodyne detector reduces the loss of security to some extent. We suggest the symmetrization of the multimode sources of entanglement as an efficient method allowing us to fully recover the security irrespectively to multimode structure of the homodyne detectors. Further, we demonstrate that by increasing the number of the fluctuating but similar source modes the multimode protocol stabilizes the security of the quantum key distribution. The result opens the pathway towards quantum key distribution with multimode sources and detectors.; Comment: 10 pages, 7 figures

Top quark physics and QCD: Progress since the TESLA TDR

Brandenburg, A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
45.44%
I review progress on investigations concerning top quark physics and QCD at a future linear e+e- collider that has been achieved since the presentation of the TESLA technical design report in spring 2001. I concentrate on studies that have been presented during the workshop series of the Extended Joint ECFA/DESY Study on Physics and Detectors for a Linear Electron-Positron Collider.; Comment: Two references added. 7 pages, 8 postscript figures, to appear in the proceedings of "The 4th ECFA/DESY Workshop on Physics and Detectors for a 90-800 GeV Linear e+e- Collider", NIKHEF, Amsterdam, The Netherlands, April 2003

ATLAS Forward Detectors and Physics

Soni, N.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/06/2010
Relevância na Pesquisa
45.48%
In this communication I describe the ATLAS forward physics program and the detectors, LUCID, ZDC and ALFA that have been designed to meet this experimental challenge. In addition to their primary role in the determination of ATLAS luminosity these detectors - in conjunction with the main ATLAS detector - will be used to study soft QCD and diffractive physics in the initial low luminosity phase of ATLAS running. Finally, I will briefly describe the ATLAS Forward Proton (AFP) project that currently represents the future of the ATLAS forward physics program.; Comment: 4 pages, Proceedings for Lake Louise Winter Institute 2010

A Neutrino-Factory Muon Storage Ring to Provide Beams for Multiple Detectors Around the World

Cline, D. B.; Fukui, Y.; Garren, A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 18/04/2000
Relevância na Pesquisa
45.46%
We briefly discuss the physics motivation for a neutrino factory with varying baseline distances of about 1000 to 9000 km. We describe the amount of non planarity of the storage ring required to service three or four detectors at once. A novel bowtie storage ring is described that could in part provide these beams; a preliminary lattice design is given. We give the space angles between the various detector locations and possible sites for neutrino factories. Finally we describe detectors at the Gran Sasso Laboratory and at a new laboratory near Carlsbad, NM to observe the neutrino interactions with wrong sign leptons.; Comment: 8 pages. Presented at the 5th Int. Conf. sponsored by UCLA on the Physics Potential and Develoment of mu^+mu^- Colliders (San Francisco, December 15-17, 1999) and to be published in the Proceedings by AIP

Prospects for Diffractive Physics with the CDF Forward Detectors at the Tevatron

Gallinaro, Michele
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 13/05/2002
Relevância na Pesquisa
45.49%
The Forward Detector upgrade project at CDF is designed to enhance the capabilities for studies of diffractive physics at the Tevatron during Run II. Studies of hard diffraction and very forward physics are some of the topics that can be addressed in the next few years at the Tevatron. The program for diffractive physics, including the detectors and their commissioning, is discussed here. All the detectors have been installed and are presently collecting data.; Comment: 11 pages, 10 figures Conference Proceedings ``LISHEP 2002 - Workshop on Diffractive Physics'' Feb. 2002

Physics with near detectors at a neutrino factory

Tang, Jian; Winter, Walter
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
45.54%
We discuss the impact of near detectors at a neutrino factory both on standard oscillation and non-standard interaction measurements. Our systematics treatment includes cross section errors, flux errors, and background uncertainties, and our near detector fluxes include the geometry of the neutrino source and the detector. Instead of a specific detector concept, we introduce qualitatively different classes of near detectors with different characteristics, such as near detectors catching the whole neutrino flux (near detector limit) versus near detectors observing a spectrum similar to that of the far detector (far detector limit). We include the low energy neutrino factory in the discussion. We illustrate for which measurements near detectors are required, discuss how many are needed, and what the role of the flux monitoring is. For instance, we demonstrate that near detectors are mandatory for the leading atmospheric parameter measurements if the neutrino factory has only one baseline, whereas systematical errors partially cancel if the neutrino factory complex includes the magic baseline. Finally, near detectors with nu_tau detection are shown to be useful for non-standard interactions.; Comment: 32 pages, 13 figures, 4 tables. Minor changes...

LHC Expectations (Machine, Detectors and Physics)

Dissertori, Guenther
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/12/2005
Relevância na Pesquisa
45.45%
Starting in two years from now, particle physics will enter a new regime in terms of energies and luminosities, thanks to the Large Hadron Collider (LHC) at CERN. This report summarizes the status of the preparations, both for the machine and the detectors, as of fall 2005. The commissioning and start-up scenarios are outlined and some highlights from the very rich physics programme are given, concentrating on measurements of Standard Model processes, as well as on early discovery scenarios. The prospects of B-physics and heavy ion collisions at LHC are also briefly discussed. The report concludes with an outlook on the ultimate physics reach and on upgrade scenarios.; Comment: Plenary talk given at the International Europhysics Conference on High Energy Physics, July 21st - 27th 2005, Lisboa, Portugal

Physics and Detectors at the LHC and the SLHC

Smith, Wesley H.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 21/12/2005
Relevância na Pesquisa
45.48%
The capabilities of the ATLAS and CMS detectors being prepared for the LHC are reviewed. Examples of physics signals accessible during early running and during mature high luminosity LHC operation are examined. The planning and options for the LHC and these detectors to increase the luminosity to 10^{35}cm^{-2}s^{-1} is presented. This upgrade, entitled the Super LHC (SLHC), would occur in the next decade. The resulting physics scope is discussed.; Comment: Invited talk at 2005 International Linear Collider Physics and Detector Workshop and Second ILC Accelerator Workshop, Snowmass, CO (Snowmass05), 3 pages, PDF

Performance evaluation of a very high resolution small animal PET imager using silicon scatter detectors

Park, Sang-June; Rogers, W. Leslie; Huh, Sam; Kagan, Harris; Honscheid, Klaus; Burdette, Don; Chesi, Enrico; Lacasta Llácer, Carlos; Llosá, Gabriela; Mikuz, Marko; Studen, Andrej; Weilhammer, Peter; Clinthorne, Neal H.
Fonte: Institute of Physics Publishing Publicador: Institute of Physics Publishing
Tipo: Artículo Formato: 2373 bytes; text/plain
ENG
Relevância na Pesquisa
45.48%
20 pages, 7 figures.-- PMID: 17473353 [PubMed].-- ISI Article Identifier: 000246177000012.-- Printed version published on May 21, 2007.; A very high resolution positron emission tomography (PET) scanner for small animal imaging based on the idea of inserting a ring of high-granularity solid-state detectors into a conventional PET scanner is under investigation. A particularly interesting configuration of this concept, which takes the form of a degenerate Compton camera, is shown capable of providing sub-millimeter resolution with good sensitivity. We present a Compton PET system and estimate its performance using a proof-of-concept prototype. A prototype single-slice imaging instrument was constructed with two silicon detectors 1 mm thick, each having 512 1.4 mm x 1.4 mm pads arranged in a 32 x 16 array. The silicon detectors were located edgewise on opposite sides and flanked by two non-position sensitive BGO detectors. The scanner performance was measured for its sensitivity, energy, timing, spatial resolution and resolution uniformity. Using the experimental scanner, energy resolution for the silicon detectors is 1%. However, system energy resolution is dominated by the 23% FWHM BGO resolution. Timing resolution for silicon is 82.1 ns FWHM due to time-walk in trigger devices. Using the scattered photons...

ATLAS silicon module assembly and qualification tests at IFIC Valencia

Bernabeu Verdú, José; Civera, José Vicente; Costa, María José; Escobar, Carlos; Fuster, Juan; García García, Carmen; García Navarro, José Enrique; González González, Francisco; González Sevilla, Sergio; Lacasta Llácer, Carlos; Llosá, Gabriel
Fonte: Institute of Physics Publishing Publicador: Institute of Physics Publishing
Tipo: Artículo Formato: 2373 bytes; text/plain
ENG
Relevância na Pesquisa
55.46%
23 pages, 24 figures.-- ISI Article Identifier: 000253651500007.-- ArXiv pre-print available at: http://arxiv.org/abs/0709.0231; ATLAS experiment, designed to probe the interactions of particles emerging out of proton proton collisions at energies of up to 14 TeV, will assume operation at the Large Hadron Collider (LHC) at CERN in 2007. This paper discusses the assembly and the quality control tests of forward detector modules for the ATLAS silicon microstrip detector assembled at the Instituto de Física Corpuscular (IFIC) in Valencia. The construction and testing procedures are outlined and the laboratory equipment is briefly described. Emphasis is given on the module quality achieved in terms of mechanical and electrical stability.; We acknowledge support of CICYT (Spain) under the project FPA2003-03878-C02-01 and of the EU under the RTN contract: HPRN-CT-2002-00292, "The 3rd Generation as a Probe for New Physics: Technological and Experimental Approach".; Peer reviewed

Detectors for Quality Assurance in Hadrontherapy

Watts, David A.
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2014 ENG
Relevância na Pesquisa
45.47%
La terapia de hadrones es actualmente una realidad médica en oncología de radiación y una técnica probada en la lucha contra el cáncer. Hoy en día, el uso de la terapia de hadrones está ampliamente extendido en el tratamiento de pacientes con tumores profundos, no operables o resistentes a la radioterapia, debido a la ventaja de administrar una alta dosis de radiación con respecto al volumen del tumor. De esta forma se obtiene un mejor del control y protección del tejido circundante comparado con la radioterapia tradicional basada en haz de fotones. A pesar de que solo 35 centros médicos están actualmente tratando a pacientes de cáncer, la terapia de hadrones sigue considerada como una técnica medica emergente. Uno de sus retos permanentes consiste en la verificación de la dosis administrada al paciente ya que las propiedades físicas de los hadrones hacen que la terapia sea efectiva solo si se administra con precisión estrictamente al volumen del tumor. El control de calidad se consigue mediante la utilización de novedosas técnicas de diagnóstico por medio de detectores de radicación similares a los desarrollados para experimentos de física de partículas que ya se vienen utilizando en la producción de imágenes médicas. Las radiografías de protones se usan no solo para verificar el estado del paciente previo a los tratamientos de radioterapia...

Calorimeters for Precision Timing Measurements in High Energy Physics

Bornheim, Adolf; Apresyan, Artur; Duarte, Javier; Pena, Cristian; Ronzhin, Anatoly; Spiropulu, Maria; Xie, Si
Fonte: Institute of Physics Publicador: Institute of Physics
Tipo: Article; PeerReviewed Formato: application/pdf
Publicado em 13/02/2015
Relevância na Pesquisa
45.45%
Current and future high energy physics particle colliders are capable to provide instantaneous luminosities of 1034 cm^(-2)s^(-1) and above. The high center of mass energy, the large number of simultaneous collision of beam particles in the experiments and the very high repetition rates of the collision events pose huge challenges. They result in extremely high particle fluxes, causing very high occupancies in the particle physics detectors operating at these machines. To reconstruct the physics events, the detectors have to make as much information as possible available on the final state particles. We discuss how timing information with a precision of around 10 ps and below can aid the reconstruction of the physics events under such challenging conditions. High energy photons play a crucial role in this context. About one third of the particle flux originating from high energy hadron collisions is detected as photons, stemming from the decays of neutral mesons. In addition, many key physics signatures under study are identified by high energy photons in the final state. They pose a particular challenge in that they can only be detected once they convert in the detector material. The particular challenge in measuring the time of arrival of a high energy photon lies in the stochastic component of the distance to the initial conversion and the size of the electromagnetic shower. They extend spatially over distances which propagation times of the initial photon and the subsequent electromagnetic shower which are large compared to the desired precision. We present studies and measurements from test beams and a cosmic muon test stand for calorimeter based timing measurements to explore the ultimate timing precision achievable for high energy photons of 10 GeV and above. We put particular focus on techniques to measure the timing with a precision of about 10 ps in association with the energy of the photon. For calorimeters utilizing scintillating materials and light guiding components...