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Title: Some New Possible Anticipated Signals for Existence of Magnetic Monopoles
Author: Qiu-He Peng, Jing-Jing Liu, Zhong-Qi Ma

We summarize some predictions from the model of supermassive object with magnetic monopoles which match up with recent astronomical observations quantitatively. They may be the signals for existence of magnetic monopoles in the supermassive objects, such as one at the Galactic Center.

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Elusive magnetic 'monopole' seen in quantum system

"Monopoles" were famously predicted to exist by physicist Paul Dirac in 1931 - but they have remained elusive.
Now scientists have engineered a synthetic monopole in a quantum system for the first time, allowing its mysterious properties to be explored.

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Künstliche magnetische Monopole entdeckt

Einem Team aus Kölner, Münchener und Dresdner Forschern ist es gelungen, künstliche magnetische Monopole zu erzeugen. Dazu verschmolzen die Wissenschaftler winzige magnetische Wirbel, sogenannte Skyrmionen. Am Verschmelzungspunkt konnten die Physiker einen Monopol nachweisen, das ähnliche Eigenschaften hat, wie ein 1931 von Paul Dirac postuliertes Elementarteilchen. Neben der Grundlagenforschung könnten die Monopole vielleicht auch Anwendungspotential haben. Weltweit wird an der Frage geforscht, ob man mit magnetischen Wirbeln vielleicht einmal Bauelemente für Computer herstellen kann.
Wenn man einen Magneten teilt, entstehen immer neue Magnete mit Nord- und Südpol. Aber ein Monopol, d.h. ein Nordpol ohne Südpol, oder ein Südpol ohne Nordpol wurde noch nicht entdeckt. In der heutigen Ausgabe der Zeitschrift Science beschreiben Forscher aus Dresden, München und Köln die Entdeckung einer neuen Art künstlicher Monopole in einem Festkörper, also von Teilchen, die ähnliche Eigenschaften wie Monopole haben, aber nur innerhalb des Materials existieren.

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Title: Search for GUT Monopoles at Super-Kamiokande
Authors: The Super-Kamiokande Collaboration: K. Ueno, K. Abe, Y. Hayato, T. Iida, K. Iyogi, J. Kameda, Y. Koshio, Y. Kozuma, M. Miura, S. Moriyama, M. Nakahata, S. Nakayama, Y. Obayashi, H. Sekiya, M. Shiozawa, Y.Suzuki, A. Takeda, Y. Takenaga, K. Ueshima, S. Yamada, T. Yokozawa, K. Martens, J. Schuemann, M. Vagins, C. Ishihara, H. Kaji, T. Kajita, K. Kaneyuki, T. McLachlan, K. Okumura, Y. Shimizu, N. Tanimoto, E. Kearns, M. Litos, J. L. Raaf, J. L. Stone, L. R. Sulak, K. Bays, W. R. Kropp, S. Mine, C. Regis, A.Renshaw, M. B. Smy, H. W. Sobel, K. S. Ganezer, J. Hill, W. E. Keig, J. S. Jang, J. Y. Kim, I. T. Lim, J. B. Albert, K. Scholberg, C. W. Walter, R. Wendell, T. Wongjirad, T. Ishizuka, S. Tasaka, J. G. Learned, S. Matsuno, T. Hasegawa, T. Ishida, T. Ishii, T. Kobayashi, T. Nakadaira, K. Nakamura, et al. (46 additional authors not shown)

GUT monopoles captured by the Sun's gravitation are expected to catalyse proton decays via the Callan-Rubakov process. In this scenario, protons, which initially decay into pions, will ultimately produce \nu_{e}, \nu_{\mu} and \bar{\nu}_{\mu}. After undergoing neutrino oscillation, all neutrino species appear when they arrive at the Earth, and can be detected by a 50,000 metric ton water Cherenkov detector, Super-Kamiokande (SK). A search for low energy neutrinos in the electron total energy range from 19 to 55 MeV was carried out with SK and gives a monopole flux limit of F_M(\sigma_0/1 mb) < 6.3 x 10^{-24} (\beta_M/10^{-3})^2 cm^{-2} s^{-1} sr^{-1} at 90% C.L., where \beta_M is the monopole velocity in units of the speed of light and \sigma_0 is the catalysis cross section at \beta_M=1. The obtained limit is more than eight orders of magnitude more stringent than the current best cosmic-ray supermassive monopole flux limit, F_M < 1 x 10^{-15} cm^{-2} s^{-1} sr^{-1} for \beta_M < 10^{-3} and also two orders of magnitude lower than the result of the Kamiokande experiment, which used a similar detection method.

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Title: Monopoles, strings and dark matter
Authors: Catalina Gomez Sanchez, Bob Holdom

We develop a scenario whereby monopoles in a hidden sector yield a decaying dark matter candidate of interest for the PAMELA and FERMI e^± excesses. The monopoles are not completely hidden due to a very small kinetic mixing and a hidden photon mass. The latter also causes the monopoles and anti-monopoles to be connected by strings. The resulting long-lived objects eventually decay to hidden photons which tend to escape galactic cores before decaying. The mass scales are those of the hidden photon (~ 500 MeV), the monopole (~ 3 TeV) and the mixing scale (close to the Planck scale). A gauge coupling in the hidden sector is the only other parameter. This coupling must be strong and this results in light point-like monopoles and light thin strings.

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Scientists have captured the first direct images of magnetic monopoles which were theoretically conceived by the British-Swiss physicist Dirac in the early 1930s who showed that their existence is consistent with the ultimate theory of matter - quantum theory.
According to the findings published on 17 Oct 2010 in the leading scientific journal Nature Physics, the scientists were able to directly image the monopoles by using the highly intense x-ray radiation from the Swiss Light Source at the Paul Scherrer Institute.

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Die Abbildung mit einem magnetischen Kraftmikroskop zeigt die Anordnung von magnetischen Nord- (helle Punkte) - und Südpolen (dunkle Punkte) auf einem lithographisch hergestellten Honigwabengitter. Bemerkenswert ist, dass in den meisten Eckpunkten abwechselnd drei Nord- bzw. drei Südpole aufeinander treffen. Dadurch entsteht eine neue magnetische Ordnung, die zwar die Spin-Eis Regeln verletzt, jedoch durch ihre Regelmäbigkeit überrascht und fasziniert. Download (345.8 kB)

Im "Spin-Eis" lassen sich exotische Eigenschaften magnetischer Systeme untersuchen: Mit mikrometerkleinen magnetischen Inseln, die sie in Form von Honigwaben in einer Ebene anordneten, gelangen Physikern der Ruhr-Universität um Prof. Dr. Hartmut Zabel überraschende Beobachtungen. Beim Anlegen eines Magnetfeldes sucht sich das System einen unerwartet geordneten Zustand aus und nimmt dabei in Kauf, dass die Pole der Magneten energetisch äuberst ungünstig zusammenliegen.

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New material is a breakthrough in magnetism

Researchers from Imperial College London have created a structure that acts like a single pole of a magnet, a feat that has evaded scientists for decades. The researchers say their new Nature Physics study takes them a step closer to isolating a 'magnetic monopole.'
Magnets have two magnetic poles, north and south. 'Like' poles, such as north and north, repel one another and 'opposite' poles, such as north and south, attract. Whichever way a magnet is cut, it will always have these two poles.
Scientists have theorised for many years that it must be possible to isolate a 'magnetic monopole', either north or south on its own, but until recently researchers have been unable to show this in experiments.

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Magnetic monopole experiment

An experiment led by a University of Alberta researcher at the European Centre for Nuclear Research, known as CERN, could dramatically change our concepts of basic physics, revolutionise our understanding of the universe and lead to technologies that only exist in science fiction.
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Magnetricity
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'Magnetricity' observed and measured for the first time
A magnetic charge can behave and interact just like an electric charge in some materials, according to new research led by the London Centre for Nanotechnology (LCN).
The findings could lead to a reassessment of current magnetism theories, as well as significant technological advances.


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