12 research outputs found

    Antimatter as Macroscopic Dark Matter

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    Antimatter macroscopic dark matter (macros) refers to a generic class of antimatter dark matter candidates that interact with ordinary matter primarily through annihilation with large cross-sections. A combination of terrestrial, astrophysical, and cosmological observations constrain a portion of the anti-macro parameter space. However, a large region of the parameter space remains unconstrained, most notably for nuclear-dense objects.Comment: 13 pages, 1 figur

    Macro detection using fluorescence detectors

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    Macroscopic dark matter (aka macros) constitutes a broad class of alternatives to particulate dark matter. We calculate the luminosity produced by the passage of a single macro as a function of its physical cross section. A general detection scheme is developed for measuring the fluorescence caused by a passing macro in the atmosphere that is applicable to any ground based or space based Fluorescence Detecting (FD) telescopes. In particular, we employ this scheme to constrain the parameter space (\sigma_{x} \mbox{ vs} \mbox{ M}_{x}) of macros than can be probed by the Pierre Auger Observatory and by the Extreme Universe Space Observatory onboard the Japanese Experiment Module (JEM-EUSO). It is of particular significance that both detectors are sensitive to macros of nuclear density, since most candidates that have been explored (excepting primordial black holes) are expected to be of approximately nuclear density.Comment: 16 pages, 5 figures, 2 tabl

    British Administration in the Federated Malay States, 1896-1920.

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    The introductory first chapter sets out the relevant geographical data, the size and distribution of the pre-1874 Malay population, and the characteristics of the traditional economy. There follows a discussion of the indigenous political system, early British contacts with the Peninsula and the way in which these culminated in the decision to intervene and establish the Residential System. Chinese and Indian immigration and the establishment of a plural society are also discussed. An analysis of the Treaty of Federation, 1895, and the development of a more efficient and better co-ordinated administrative system under the guidance of a Resident-General are the main subjects treated in Chapter II. Tendencies towards greater centralisation and the reactions these generated among British Residents are also examined. Chapter III deals with the Federal Council Agreement of 1909 and the role played by Governor Anderson in the measure which resulted in even greater centralisation and uniformity of administration The working of the Federal Council and the role of un-officials in its deliberations are outlined. The Chief Secretary Enactment of 1911 is also examined. Some consideration is given to the spectacular success achieved by the tin and rubber industries and the repercussions these had on political affairs. The diminution of the Malay aristocracy forms the subject of Chapter IV. British policies and administrative methods which served to push them more and more into the background are discussed and attention is drawn to what little protest these aroused among the Malay Rulers. Attempts are also made to establish the whole attitude of the British authorities towards the role of the Sultans in the government of the country. The effects of British rule on the Malay masses are discussed in Chapter V. The administration's educational, employment, social, and economic policies towards the Malays are studied and their failure to appreciate the needs of the indigenous population are highlighted

    Macroscopic dark matter constraints from bolide camera networks

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