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New new-phenomena results from D-Zero

Description: We have searched for diphoton events ({gamma}{gamma} /E{sub T}) with large missing transverse momentum, {gamma} /E{sub T} events ({gamma} /E{sub T}+{ge} 2 jets) with two or more jets, and diphoton events ({gamma}{gamma}) with high transverse energies in p{anti p} collisions at {radical}s = 1.8 TeV using approximately 100 pb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron in 1992-1996. No excess of events beyond the expected backgrounds is observed. The null results are interpreted in supersymmetric models with a dominant {tilde {xi}}{sup 0}{sub 2} {yields} {gamma}{tilde {xi}}{sup 0}{sub 1} decay and in terms of Dirac pointlike monopole production.
Date: June 1, 1998
Creator: Qian, J.
Partner: UNT Libraries Government Documents Department


Description: An electromagnetic search for magnetic monopoles of the minimum size predicted by Dirac, or of any larger magnitude, has been performed on 8.37 kilograms of lunar surface material returned by the Apollo 11 crew. No monopole was found. This experiment sets new limits on the production cross section for monopoles, and on their occurrence in cosmic radiation.
Date: December 1, 1969
Creator: Alvarez, Luis W.; Eberhard, Philippe H.; Ross, Ronald R. & Watt,Robert D.
Partner: UNT Libraries Government Documents Department

Status of searches for magnetic monopoles

Description: The recent experiment reporting the discovery of a monopole is compared to the negative experiments performed previously. The different determinations of the flux of monopoles are contradictory. It is likely that the event reported as a monopole may be given another interpretation. (auth)
Date: October 1, 1975
Creator: Eberhard, P.
Partner: UNT Libraries Government Documents Department

Analysis of a reported magnetic monopole

Description: It is shown that there are several substantive errors in a previous work on a cosmic ray event which is consistent with the hypothesis that it was caused by a magnetic monopole. It is shown that the data points fit to the hypothesis that the responsible particle is a platinum nucleus fragmenting to osmium and then to tantalum. (JFP)
Date: September 16, 1975
Creator: Alvarez, L.W.
Partner: UNT Libraries Government Documents Department

The IceCube Collaboration:contributions to the 30 th International Cosmic Ray Conference (ICRC 2007),

Description: This paper bundles 40 contributions by the IceCube collaboration that were submitted to the 30th International Cosmic Ray Conference ICRC 2007. The articles cover studies on cosmic rays and atmospheric neutrinos, searches for non-localized, extraterrestrial {nu}{sub e}, {nu}{sub {mu}} and {nu}{sub {tau}} signals, scans for steady and intermittent neutrino point sources, searches for dark matter candidates, magnetic monopoles and other exotic particles, improvements in analysis techniques, as well as future detector extensions. The IceCube observatory will be finalized in 2011 to form a cubic-kilometer ice-Cherenkov detector at the location of the geographic South Pole. At the present state of construction, IceCube consists of 52 paired IceTop surface tanks and 22 IceCube strings with a total of 1426 Digital Optical Modules deployed at depths up to 2350 m. The observatory also integrates the 19 string AMANDA subdetector, that was completed in 2000 and extends IceCube's reach to lower energies. Before the deployment of IceTop, cosmic air showers were registered with the 30 station SPASE-2 surface array. IceCube's low noise Digital Optical Modules are very reliable, show a uniform response and record waveforms of arriving photons that are resolvable with nanosecond precision over a large dynamic range. Data acquisition, reconstruction and simulation software are running in production mode and the analyses, profiting from the improved data quality and increased overall sensitivity, are well under way.
Date: November 2, 2007
Creator: Collaboration, IceCube & Ackermann, M.
Partner: UNT Libraries Government Documents Department

Searches for long lived particles at the Tevatron

Description: Several searches have been performed for long lived particles using data collected by the CDF and D0 detectors at the Fermilab Tevatron collider. These include searches for charged massive stable particles, stopped gluinos, neutral long-lived particles decaying to muons, and magnetic monopoles. These proceedings [1] review recent experimental results from Run II analyses.
Date: April 1, 2008
Creator: Bose, Tulika & U., /Brown
Partner: UNT Libraries Government Documents Department

Search for Monopoles Above the 15-Foot Bubble Chamber

Description: Magnetic monopoles having energies less than about 40 TeV will be slowed to their terminal velocity by the earth's atmosphere. They may then be gathered by the fringing magnetic field of the 15-foot bubble chamber. We propose placing detectors of Lexan and nuclear emulsion at convenient locations above and below the bubble chamber. Such a systom would be sensitive to monopole masses between 10 GeV and 100 TeV and to monopole charges between {approx}0.7 and 10 hc/2e. The experiment would require the construction of a special light roof and would run for 5 weeks during a time when the bubble chamber is filled with air and not in use for other experiments. This study would lower the existing limit on in-flight detection of monopoles (at the earth's surface) by a factor of 20.
Date: January 1, 1976
Creator: Bartlett, D.F.; Soo, Daniel; U., /Colorado; Fleischer, Robert L.; Hart Jr., Howard R.; Mogro-Campero, Antonio et al.
Partner: UNT Libraries Government Documents Department

Can EPR non-locality be geometrical?

Description: The presence in Quantum Mechanics of non-local correlations is one of the two fundamentally non-intuitive features of that theory. The non-local correlations themselves fall into two classes: EPR and Geometrical. The non-local characteristics of the geometrical type are well-understood and are not suspected of possibly generating acausal features, such as faster-than-light propagation of information. This has especially become true since the emergence of a geometrical treatment for the relevant gauge theories, i.e. Fiber Bundle geometry, in which the quantum non-localities are seen to correspond to pure homotopy considerations. This aspect is reviewed in section 2. Contrary-wise, from its very conception, the EPR situation was felt to be paradoxical. It has been suggested that the non-local features of EPR might also derive from geometrical considerations, like all other non-local characteristics of QM. In[7], one of the authors was able to point out several plausibility arguments for this thesis, emphasizing in particular similarities between the non-local correlations provided by any gauge field theory and those required by the preservation of the quantum numbers of the original EPR state-vector, throughout its spatially-extended mode. The derivation was, however, somewhat incomplete, especially because of the apparent difference between, on the one hand, the closed spatial loops arising in the analysis of the geometrical non-localities, from Aharonov-Bohm and Berry phases to magnetic monopoles and instantons, and on the other hand, in the EPR case, the open line drawn by the positions of the two moving decay products of the disintegrating particle. In what follows, the authors endeavor to remove this obstacle and show that as in all other QM non-localities, EPR is somehow related to closed loops, almost involving homotopy considerations. They develop this view in section 3.
Date: October 1, 1995
Creator: Ne`eman, Y. & Botero, A.
Partner: UNT Libraries Government Documents Department

Quantum groups: Geometry and applications

Description: The main theme of this thesis is a study of the geometry of quantum groups and quantum spaces, with the hope that they will be useful for the construction of quantum field theory with quantum group symmetry. The main tool used is the Faddeev-Reshetikhin-Takhtajan description of quantum groups. A few content-rich examples of quantum complex spaces with quantum group symmetry are treated in details. In chapter 1, the author reviews some of the basic concepts and notions for Hopf algebras and other background materials. In chapter 2, he studies the vector fields of quantum groups. A compact realization of these vector fields as pseudodifferential operators acting on the linear quantum spaces is given. In chapter 3, he describes the quantum sphere as a complex quantum manifold by means of a quantum stereographic projection. A covariant calculus is introduced. An interesting property of this calculus is the existence of a one-form realization of the exterior differential operator. The concept of a braided comodule is introduced and a braided algebra of quantum spheres is constructed. In chapter 4, the author considers the more general higher dimensional quantum complex projective spaces and the quantum Grassman manifolds. Differential calculus, integration and braiding can be introduced as in the one dimensional case. Finally, in chapter 5, he studies the framework of quantum principal bundle and construct the q-deformed Dirac monopole as a quantum principal bundle with a quantum sphere as the base and a U(1) with non-commutative calculus as the fiber. The first Chern class can be introduced and integrated to give the monopole charge.
Date: May 13, 1996
Creator: Chu, C. S.
Partner: UNT Libraries Government Documents Department

Symplectic structure of isospin particles in Yang-Mills fields

Description: Using Dirac`s constraint analysis, we explore the Hamiltonian formalism of isospin particles in external Yang-Mills fields without kinetic and potential energy term. We consider an example of isospin particle in `t Hooft-Polyakov magnetic monopole field and discuss possible quantization condition of magnetic charge in terms of geometric quantization.
Date: January 1, 1992
Creator: Oh, P.
Partner: UNT Libraries Government Documents Department


Description: The charges of magnetic monopoles are constrained to a multiple of 2{pi} times the inverse of the elementary unit electric charge. In the standard model, quarks have fractional charge, raising the question of whether the basic magnetic monopole unit is a multiple of 2{pi} or three times that. A simple lattice construction shows how a magnetic monopole of the lower strength is possible if it interacts with gluonic fields as well. Such a monopole is thus a hadron. This is consistent with the construction of magnetic monopoles in grand unified theories.
Date: June 21, 2004
Creator: CREUTZ, M.
Partner: UNT Libraries Government Documents Department

Seeing the magnetic monopole through the mirror of topological surface states

Description: Existence of the magnetic monopole is compatible with the fundamental laws of nature, however, this illusive particle has yet to be detected experimentally. In this work, we show that an electric charge near the topological surface state induces an image magnetic monopole charge due to the topological magneto-electric effect. The magnetic field generated by the image magnetic monopole can be experimentally measured, and the inverse square law of the field dependence can be determined quantitatively. We propose that this effect can be used to experimentally realize a gas of quantum particles carrying fractional statistics, consisting of the bound states of the electric charge and the image magnetic monopole charge.
Date: March 25, 2010
Creator: Qi, Xiao-Liang; Li, Rundong; /Stanford U., Phys. Dept.; Zang, Jiadong; U., /Fudan; Zhang, Shou-Cheng et al.
Partner: UNT Libraries Government Documents Department

Proposal for a search for magnetic monopoles at NAL

Description: The discovery of a magnetic monopole would be an important experimental result. It would give a reason for the phenomenon of exact electric charge quantization that is not explained yet any other way. Schwinger's dyon theory makes monopoles even more important because they would also be the quarks, i.e., the building blocks of the hadrons. Schwinger's scheme requires the electric charge of the monopoles to be a multiple of 1/3 of the electron charge while all magnetically neutral particles must have electric charges equal to an integer times the electron charge. Monopoles would be also responsible for CP violations.
Date: May 1, 1970
Creator: Alvarez, L.W.; Eberhard, P.H.; Ross, R.R.; /LBL, Berkeley; Watt, R.D. & /SLAC
Partner: UNT Libraries Government Documents Department

The Time-of-Flight trigger at CDF

Description: The Time-of-Flight (TOF) detector measures the arrival time and deposited energy of charged particles reaching scintillator bars surrounding the central tracking region of the CDF detector. Requiring high ionization in the TOF system provides a unique trigger capability, which has been used for a magnetic monopole search. Other uses, with smaller pulse height thresholds, include a high-multiplicity charged-particle trigger useful for QCD studies and a much improved cosmic ray trigger for calibrating other detector components. Although not designed as input to CDF's global Level 1 trigger, the TOF system has been easily adapted to this role by the addition of 24 cables, new firmware, and four custom TOF trigger boards (TOTRIBs). This article describes the TOF trigger.
Date: May 1, 2006
Creator: Bauer, G.; Mulhearn, M.J.; Paus, Ch.; Schieferdecker, P.; Tether, S.; /MIT et al.
Partner: UNT Libraries Government Documents Department

Massless and massive monopoles carrying nonabelian magnetic charges

Description: The properties of BPS monopoles carrying nonabelian magnetic charges are investigated by following the behavior of the moduli space of solutions as the Higgs field is varied from a value giving a purely abelian symmetry breaking to one that leaves a nonabelian subgroup of the gauge symmetry unbroken. As the limit of nonabelian unbroken symmetry is reached, some of the fundamental abelian monopoles remain massive but acquire nonabelian magnetic charges. The BPS mass formula indicates that others should because massless in this limit. These do not correspond to distinct solitons, but instead are manifested as a ``nonabelian cloud`` surrounding the massive monopoles, with their position and phase degrees of freedom being transformed into parameters characterizing the cloud.
Date: October 1, 1996
Creator: Weinberg, E.J.
Partner: UNT Libraries Government Documents Department

Cosmological and astrophysical implications of magnetic monopoles

Description: Among Dirac's many contributions to modern physics is the idea that charge quantization is natural in a theory with magnetic monopoles. The existence of magnetic monopoles would have drastic effects on the evolution of the universe, on galactic magnetic fields, and perhaps on the x-ray luminosity of neutron stars. Some astrophysical implications of massive magnetic monopoles are reviewed here.
Date: March 11, 1983
Creator: Kolb, E.W.
Partner: UNT Libraries Government Documents Department

A Direct Search for Dirac Magnetic Monopoles

Description: Magnetic monopoles are highly ionizing and curve in the direction of the magnetic field. A new dedicated magnetic monopole trigger at CDF, which requires large light pulses in the scintillators of the time-of-flight system, remains highly efficient to monopoles while consuming a tiny fraction of the available trigger bandwidth. A specialized offline reconstruction checks the central drift chamber for large dE/dx tracks which do not curve in the plane perpendicular to the magnetic field. We observed zero monopole candidate events in 35.7 pb{sup -1} of proton-antiproton collisions at {radical}s = 1.96 TeV. This implies a monopole production cross section limit {sigma} < 0.2 pb for monopoles with mass between 100 and 700 GeV, and, for a Drell-Yan like pair production mechanism, a mass limit m > 360 GeV.
Date: October 1, 2004
Creator: Mulhearn, Michael James & /MIT
Partner: UNT Libraries Government Documents Department

Searches at the Tevatron

Description: The CDF and D0 collider experiments at Fermilab have searched for evidence of physics beyond the Standard Model of particle physics. We report on the results of searches for extra heavy gauge bosons, quark-lepton compositeness, leptoquarks, and magnetic monopoles in p{bar p} collisions at {radical}s = 1.96 TeV. No evidence of new signals were found, therefore we derive limits on the model parameters.
Date: June 1, 2005
Creator: Illingworth, Robert & /Fermilab
Partner: UNT Libraries Government Documents Department

First Results from IceCube

Description: IceCube is a 1 km{sup 3} neutrino observatory being built to study neutrino production in active galactic nuclei, gamma-ray bursts, supernova remnants, and a host of other astrophysical sources. High-energy neutrinos may signal the sources of ultra-high energy cosmic rays. IceCube will also study many particle-physics topics: searches for WIMP annihilation in the Earth or the Sun, and for signatures of supersymmetry in neutrino interactions, studies of neutrino properties, including searches for extra dimensions, and searches for exotica such as magnetic monopoles or Q-balls. IceCube will also study the cosmic-ray composition. In January, 2005, 60 digital optical modules (DOMs) were deployed in the South Polar ice at depths ranging from 1450 to 2450 meters, and 8 ice-tanks, each containing 2 DOMs were deployed as part of a surface air-shower array. All 76 DOMs are collecting high-quality data. After discussing the IceCube physics program and hardware, I will present some initial results with the first DOMs.
Date: January 12, 2006
Creator: Klein, Spencer R.
Partner: UNT Libraries Government Documents Department

Nonabelian Monopoles

Description: We study topological as well as dynamical properties of BPS nonabelian magnetic monopoles of Goddard-Nuyts-Olive-Weinberg type in $ G=SU(N)$, $USp(2N)$ and SO(N) gauge theories, spontaneously broken to nonabelian subgroups $H$. We find that monopoles transform under the group dual to $H$ in a tensor representation of rank determined by the corresponding element in $\pi_1(H)$. When the system is embedded in a $\cal N=2$ supersymmetric theory with an appropriate set of flavors with appropriate bare masses, the BPS monopoles constructed semiclassically persist in the full quantum theory. This result supports the identification of"dual quarks'' found at $r$-vacua of $\cal N=2$ theories with the nonabelian magnetic monopoles. We present several consistency checks of our monopole spectra.
Date: June 23, 2004
Creator: Auzzi, Roberto; Bolognesi, Stefano; Evslin, Jarah; Konishi, Kenichi & Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department

Search for massive long lived particles in aluminum targets irradiated by 300 GeV and 400 GeV protons

Description: A directional gas Cherenkov counter, which employed six phototubes to sample Cherenkov light from single particles having a gamma greater than ~10 was used to achieve accidental rates of less than one per day if operated near targets with surface radiation levels of as high as 10/sup +3/ r/hr. The cosmic ray background measured by the apparatus was reduced to less than one per day by mounting our directional Cherenkov counter above the irradiated targets and facing toward the earth. Two searches of a few days duration, after bombardments at energies of 300 and 400 GeV with >10/sup 16/ protons at NAL, were made in four inch thick targets of aluminum, mounted just down stream from another aluminum target. No long-lived particles were observed with cross sections for production and capture of approximately less than a micro-micro barn in a lifetime range of a few to a few thousand hours. (auth) from the decay of a long-lived intermediate state. (auth)
Date: September 11, 1973
Creator: Frankel, S.; Frati, W.; Resvanis, L.; Yang, W. & Nezrick, F.
Partner: UNT Libraries Government Documents Department

Excitation of simple atoms by slow magnetic monopoles

Description: We present a theory of excitation of simple atoms by slow moving massive monopoles. Previously presented results for a monopole of Dirac strength on hydrogen and helium are reviewed. The hydrogen theory is extended to include arbitrary integral multiples of the Dirac pole strength. The excitation of helium by double strength poles and by dyons is also discussed. It is concluded that a helium proportional counter is a reliable and effective detector for monopoles of arbitrary strength, and for negatively charged dyons.
Date: January 1, 1984
Creator: Kroll, N.M.; Parke, S.J.; Ganapathi, V. & Drell, S.D.
Partner: UNT Libraries Government Documents Department