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Non-Collider Searches for Stable Massive Particles

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Non-Collider Searches for Stable Massive Particles Non-collider searches for stable massive particles S. Burdina, M. Fairbairnb, P. Mermodc,, D. Milsteadd, J. Pinfolde, T. Sloanf, W. Taylorg aDepartment of Physics, University of Liverpool, Liverpool L69 7ZE, UK bDepartment of Physics, King's College London, London WC2R 2LS, UK cParticle Physics department, University of Geneva, 1211 Geneva 4, Switzerland dDepartment of Physics, Stockholm University, 106 91 Stockholm, Sweden ePhysics Department, University of Alberta, Edmonton, Alberta, Canada T6G 0V1 fDepartment of Physics, Lancaster University, Lancaster LA1 4YB, UK gDepartment of Physics and Astronomy, York University, Toronto, ON, Canada M3J 1P3 Abstract The theoretical motivation for exotic stable massive particles (SMPs) and the results of SMP searches at non-collider facilities are reviewed. SMPs are defined such that they would be suffi- ciently long-lived so as to still exist in the cosmos either as Big Bang relics or secondary collision products, and sufficiently massive such that they are typically beyond the reach of any conceiv- able accelerator-based experiment. The discovery of SMPs would address a number of important questions in modern physics, such as the origin and composition of dark matter and the unifi- cation of the fundamental forces. This review outlines the scenarios predicting SMPs and the techniques used at non-collider experiments to look for SMPs in cosmic rays and bound in mat- ter. The limits so far obtained on the fluxes and matter densities of SMPs which possess various detection-relevant properties such as electric and magnetic charge are given. Contents 1 Introduction 4 2 Theory and cosmology of various kinds of SMPs 4 2.1 New particle states (elementary or composite) . .5 2.1.1 General considerations . .5 2.1.2 SMPs as heavy leptons and hadrons . .5 2.1.3 Fractionally charged particles . .7 2.1.4 Dark atoms and mirror matter . .7 2.1.5 Strange quark matter (strangelets and nuclearites) . .8 2.1.6 Fermionic exotic compact stars . 10 2.2 Magnetic monopoles . 10 2.2.1 Electric-magnetic duality . 11 2.2.2 The Dirac quantisation condition . 11 arXiv:1410.1374v1 [hep-ph] 6 Oct 2014 2.2.3 GUT monopoles . 12 2.2.4 Monopole catalysis of proton decay . 13 2.2.5 Relic abundance of topological defects | The Kibble Mechanism and in- flation . 13 2.2.6 Monopoles in extra dimensions and in string theory . 15 2.2.7 Monopole acceleration in galactic magnetic fields . 16 2.2.8 Monopole phenomenology . 18 Preprint submitted to Elsevier October 7, 2014 2.3 Field configurations other than monopoles . 18 2.3.1 Q-balls . 18 2.3.2 Primordial black holes . 19 2.3.3 Black hole remnants . 20 2.4 Summary . 21 3 Interactions of SMPs with matter 21 3.1 Ionisation energy loss for electrically charged SMPs . 21 3.2 Other sources of energy loss for electrically charged SMPs . 22 3.2.1 Hadronising SMPs . 22 3.2.2 Mirror matter . 23 3.2.3 Strange quark matter . 23 3.2.4 Q-balls . 24 3.2.5 Small black holes . 24 3.3 Energy loss for magnetic monopoles . 24 3.3.1 Range of monopoles in matter . 26 3.3.2 Monopole binding . 28 4 Searches for heavy isotopes of matter 29 4.1 Experimental techniques . 29 4.2 Choice of materials . 30 4.3 Mass spectrometers . 30 4.4 Atomic spectroscopy . 31 4.5 Radiochemical properties . 32 4.6 Gamma rays following neutron absorption . 33 4.7 Rutherford back scattering . 33 4.8 Heavy-ion activation . 33 4.9 Summary . 33 5 Searches for magnetic monopoles in matter 35 5.1 Experimental strategies . 36 5.1.1 Low-mass monopoles . 36 5.1.2 High-mass monopoles . 36 5.2 Experimental techniques . 37 5.2.1 Extraction technique . 37 5.2.2 Induction technique . 37 5.3 Atmosphere . 38 5.4 Oceans . 39 5.5 Moon rocks . 40 5.6 Meteorites . 40 5.7 Polar volcanic rocks . 41 5.8 Iron furnace . 41 5.9 Indirect searches . 41 5.10 Summary . 42 2 6 Searches at cosmic ray facilities 42 6.1 Induction detectors . 42 6.2 Ionisation arrays . 43 6.2.1 Active detectors . 43 6.2.2 Plastic nuclear-track detectors . 44 6.2.3 Ancient mica . 46 6.3 Water or ice neutrino observatories . 47 6.3.1 Cherenkov light emission . 47 6.3.2 Radio emission . 48 6.4 Gravitational-wave detectors and acoustic sensors . 49 6.5 Air-shower observatories . 49 6.6 Balloon and space particle telescopes . 50 6.7 Catalysis of nucleon decay . 50 6.7.1 Underground nucleon-decay detectors . 50 6.7.2 Neutrinos from the Sun . 51 6.7.3 Neutron stars . 51 6.8 Discussion of candidate events . 52 6.9 Connecting cosmic-ray and collider monopole production . 52 6.10 Summary . 55 7 Searches for macroscopic composite objects 57 7.1 Gravitational lensing . 57 7.1.1 Microlensing . 58 7.1.2 Femtolensing of gamma-ray bursts . 58 7.2 Meteoroids . 59 7.2.1 Seismic detection . 59 7.2.2 Meteors . 60 7.2.3 Comets . 61 7.2.4 Asteroids . 61 7.3 Earth core radiography . 62 7.4 Indirect searches . 62 7.4.1 Geothermal effects . 62 7.4.2 Existence of old neutron stars . 62 7.4.3 Solar oscillations . 63 7.4.4 Dynamical effects . 63 7.4.5 Galactic and cosmic diffuse radiation . 63 7.4.6 Bursts from black-hole evaporation . 63 7.5 Summary . 64 8 Summary and outlook 65 3 1. Introduction The field of elementary particle physics finds itself at an interesting juncture. Collider ex- periments at the TeV scale have so far failed to falsify the Standard Model (SM) [1]. There are, however, a number of reasons to suppose that hitherto unobserved particles exist at or above the TeV scale. The requirement of naturalness in the Higgs sector typically mandates the existence of exotic particles. Similarly, there exist a number of theories of dark matter involving heavy particles and/or new states of matter. Furthermore, progress in particle physics has often been made by unexpected discoveries as high mass scales are accessed, prompting new questions to be asked. Non-collider experiments offer promising means to explore mass regions beyond that available at colliders. This paper summarises the results of non-collider searches for a specific class of new phenomena: stable massive particles1 (SMPs) which are not predicted within the SM and which can be directly observed via their strong and/or electromagnetic interactions in a detector. SMPs are common features of theories beyond the SM [2]. Examples include supersymmetric stable particles and magnetic monopoles. SMP searches are thus.
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