Dark Matter Searches at the LHC
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Dark Energy and Dark Matter As Inertial Effects Introduction
Dark Energy and Dark Matter as Inertial Effects Serkan Zorba Department of Physics and Astronomy, Whittier College 13406 Philadelphia Street, Whittier, CA 90608 [email protected] ABSTRACT A disk-shaped universe (encompassing the observable universe) rotating globally with an angular speed equal to the Hubble constant is postulated. It is shown that dark energy and dark matter are cosmic inertial effects resulting from such a cosmic rotation, corresponding to centrifugal (dark energy), and a combination of centrifugal and the Coriolis forces (dark matter), respectively. The physics and the cosmological and galactic parameters obtained from the model closely match those attributed to dark energy and dark matter in the standard Λ-CDM model. 20 Oct 2012 Oct 20 ph] - PACS: 95.36.+x, 95.35.+d, 98.80.-k, 04.20.Cv [physics.gen Introduction The two most outstanding unsolved problems of modern cosmology today are the problems of dark energy and dark matter. Together these two problems imply that about a whopping 96% of the energy content of the universe is simply unaccounted for within the reigning paradigm of modern cosmology. arXiv:1210.3021 The dark energy problem has been around only for about two decades, while the dark matter problem has gone unsolved for about 90 years. Various ideas have been put forward, including some fantastic ones such as the presence of ghostly fields and particles. Some ideas even suggest the breakdown of the standard Newton-Einstein gravity for the relevant scales. Although some progress has been made, particularly in the area of dark matter with the nonstandard gravity theories, the problems still stand unresolved. -
Dark Matter and the Early Universe: a Review Arxiv:2104.11488V1 [Hep-Ph
Dark matter and the early Universe: a review A. Arbey and F. Mahmoudi Univ Lyon, Univ Claude Bernard Lyon 1, CNRS/IN2P3, Institut de Physique des 2 Infinis de Lyon, UMR 5822, 69622 Villeurbanne, France Theoretical Physics Department, CERN, CH-1211 Geneva 23, Switzerland Institut Universitaire de France, 103 boulevard Saint-Michel, 75005 Paris, France Abstract Dark matter represents currently an outstanding problem in both cosmology and particle physics. In this review we discuss the possible explanations for dark matter and the experimental observables which can eventually lead to the discovery of dark matter and its nature, and demonstrate the close interplay between the cosmological properties of the early Universe and the observables used to constrain dark matter models in the context of new physics beyond the Standard Model. arXiv:2104.11488v1 [hep-ph] 23 Apr 2021 1 Contents 1 Introduction 3 2 Standard Cosmological Model 3 2.1 Friedmann-Lema^ıtre-Robertson-Walker model . 4 2.2 A quick story of the Universe . 5 2.3 Big-Bang nucleosynthesis . 8 3 Dark matter(s) 9 3.1 Observational evidences . 9 3.1.1 Galaxies . 9 3.1.2 Galaxy clusters . 10 3.1.3 Large and cosmological scales . 12 3.2 Generic types of dark matter . 14 4 Beyond the standard cosmological model 16 4.1 Dark energy . 17 4.2 Inflation and reheating . 19 4.3 Other models . 20 4.4 Phase transitions . 21 5 Dark matter in particle physics 21 5.1 Dark matter and new physics . 22 5.1.1 Thermal relics . 22 5.1.2 Non-thermal relics . -
The Large Hadron Collider Lyndon Evans CERN – European Organization for Nuclear Research, Geneva, Switzerland
34th SLAC Summer Institute On Particle Physics (SSI 2006), July 17-28, 2006 The Large Hadron Collider Lyndon Evans CERN – European Organization for Nuclear Research, Geneva, Switzerland 1. INTRODUCTION The Large Hadron Collider (LHC) at CERN is now in its final installation and commissioning phase. It is a two-ring superconducting proton-proton collider housed in the 27 km tunnel previously constructed for the Large Electron Positron collider (LEP). It is designed to provide proton-proton collisions with unprecedented luminosity (1034cm-2.s-1) and a centre-of-mass energy of 14 TeV for the study of rare events such as the production of the Higgs particle if it exists. In order to reach the required energy in the existing tunnel, the dipoles must operate at 1.9 K in superfluid helium. In addition to p-p operation, the LHC will be able to collide heavy nuclei (Pb-Pb) with a centre-of-mass energy of 1150 TeV (2.76 TeV/u and 7 TeV per charge). By modifying the existing obsolete antiproton ring (LEAR) into an ion accumulator (LEIR) in which electron cooling is applied, the luminosity can reach 1027cm-2.s-1. The LHC presents many innovative features and a number of challenges which push the art of safely manipulating intense proton beams to extreme limits. The beams are injected into the LHC from the existing Super Proton Synchrotron (SPS) at an energy of 450 GeV. After the two rings are filled, the machine is ramped to its nominal energy of 7 TeV over about 28 minutes. In order to reach this energy, the dipole field must reach the unprecedented level for accelerator magnets of 8.3 T. -
Effective Description of Dark Matter As a Viscous Fluid
Motivation Framework Perturbation theory Effective viscosity Results FRG improvement Conclusions Effective Description of Dark Matter as a Viscous Fluid Nikolaos Tetradis University of Athens Work with: D. Blas, S. Floerchinger, M. Garny, U. Wiedemann . N. Tetradis University of Athens Effective Description of Dark Matter as a Viscous Fluid Motivation Framework Perturbation theory Effective viscosity Results FRG improvement Conclusions Distribution of dark and baryonic matter in the Universe Figure: 2MASS Galaxy Catalog (more than 1.5 million galaxies). N. Tetradis University of Athens Effective Description of Dark Matter as a Viscous Fluid Motivation Framework Perturbation theory Effective viscosity Results FRG improvement Conclusions Inhomogeneities Inhomogeneities are treated as perturbations on top of an expanding homogeneous background. Under gravitational attraction, the matter overdensities grow and produce the observed large-scale structure. The distribution of matter at various redshifts reflects the detailed structure of the cosmological model. Define the density field δ = δρ/ρ0 and its spectrum hδ(k)δ(q)i ≡ δD(k + q)P(k): . N. Tetradis University of Athens Effective Description of Dark Matter as a Viscous Fluid 31 timation method in its entirety, but it should be equally valid. 7.3. Comparison to other results Figure 35 compares our results from Table 3 (modeling approach) with other measurements from galaxy surveys, but must be interpreted with care. The UZC points may contain excess large-scale power due to selection function effects (Padmanabhan et al. 2000; THX02), and the an- gular SDSS points measured from the early data release sample are difficult to interpret because of their extremely broad window functions. -
Anomalous Muon Magnetic Moment, Supersymmetry, Naturalness, LHC Search Limits and the Landscape
OU-HEP-210415 Anomalous muon magnetic moment, supersymmetry, naturalness, LHC search limits and the landscape Howard Baer1∗, Vernon Barger2†, Hasan Serce1‡ 1Homer L. Dodge Department of Physics and Astronomy, University of Oklahoma, Norman, OK 73019, USA 2Department of Physics, University of Wisconsin, Madison, WI 53706 USA Abstract The recent measurement of the muon anomalous magnetic moment aµ ≡ (g − 2)µ=2 by the Fermilab Muon g − 2 experiment sharpens an earlier discrepancy between theory and the BNL E821 experiment. We examine the predicted ∆aµ ≡ aµ(exp) − aµ(th) in the context of supersymmetry with low electroweak naturalness (restricting to models which give a plausible explanation for the magnitude of the weak scale). A global analy- sis including LHC Higgs mass and sparticle search limits points to interpretation within the normal scalar mass hierarchy (NSMH) SUSY model wherein first/second generation matter scalars are much lighter than third generation scalars. We present a benchmark model for a viable NSMH point which is natural, obeys LHC Higgs and sparticle mass constraints and explains the muon magnetic anomaly. Aside from NSMH models, then we find the (g − 2)µ anomaly cannot be explained within the context of natural SUSY, where a variety of data point to decoupled first/second generation scalars. The situation is worse within the string landscape where first/second generation matter scalars are pulled arXiv:2104.07597v2 [hep-ph] 16 May 2021 to values in the 10 − 50 TeV range. An alternative interpretation for SUSY models with decoupled scalar masses is that perhaps the recent lattice evaluation of the hadronic vac- uum polarization could be confirmed which leads to a Standard Model theory-experiment agreement in which case there is no anomaly. -
Modified Newtonian Dynamics
J. Astrophys. Astr. (December 2017) 38:59 © Indian Academy of Sciences https://doi.org/10.1007/s12036-017-9479-0 Modified Newtonian Dynamics (MOND) as a Modification of Newtonian Inertia MOHAMMED ALZAIN Department of Physics, Omdurman Islamic University, Omdurman, Sudan. E-mail: [email protected] MS received 2 February 2017; accepted 14 July 2017; published online 31 October 2017 Abstract. We present a modified inertia formulation of Modified Newtonian dynamics (MOND) without retaining Galilean invariance. Assuming that the existence of a universal upper bound, predicted by MOND, to the acceleration produced by a dark halo is equivalent to a violation of the hypothesis of locality (which states that an accelerated observer is pointwise inertial), we demonstrate that Milgrom’s law is invariant under a new space–time coordinate transformation. In light of the new coordinate symmetry, we address the deficiency of MOND in resolving the mass discrepancy problem in clusters of galaxies. Keywords. Dark matter—modified dynamics—Lorentz invariance 1. Introduction the upper bound is inferred by writing the excess (halo) acceleration as a function of the MOND acceleration, The modified Newtonian dynamics (MOND) paradigm g (g) = g − g = g − gμ(g/a ). (2) posits that the observations attributed to the presence D N 0 of dark matter can be explained and empirically uni- It seems from the behavior of the interpolating function fied as a modification of Newtonian dynamics when the as dictated by Milgrom’s formula (Brada & Milgrom gravitational acceleration falls below a constant value 1999) that the acceleration equation (2) is universally −10 −2 of a0 10 ms . -
MIT at the Large Hadron Collider—Illuminating the High-Energy Frontier
Mit at the large hadron collider—Illuminating the high-energy frontier 40 ) roland | klute mit physics annual 2010 gunther roland and Markus Klute ver the last few decades, teams of physicists and engineers O all over the globe have worked on the components for one of the most complex machines ever built: the Large Hadron Collider (LHC) at the CERN laboratory in Geneva, Switzerland. Collaborations of thousands of scientists have assembled the giant particle detectors used to examine collisions of protons and nuclei at energies never before achieved in a labo- ratory. After initial tests proved successful in late 2009, the LHC physics program was launched in March 2010. Now the race is on to fulfill the LHC’s paradoxical mission: to complete the Stan- dard Model of particle physics by detecting its last missing piece, the Higgs boson, and to discover the building blocks of a more complete theory of nature to finally replace the Standard Model. The MIT team working on the Compact Muon Solenoid (CMS) experiment at the LHC stands at the forefront of this new era of particle and nuclear physics. The High Energy Frontier Our current understanding of the fundamental interactions of nature is encap- sulated in the Standard Model of particle physics. In this theory, the multitude of subatomic particles is explained in terms of just two kinds of basic building blocks: quarks, which form protons and neutrons, and leptons, including the electron and its heavier cousins. From the three basic interactions described by the Standard Model—the strong, electroweak and gravitational forces—arise much of our understanding of the world around us, from the formation of matter in the early universe, to the energy production in the Sun, and the stability of atoms and mit physics annual 2010 roland | klute ( 41 figure 1 A photograph of the interior, central molecules. -
Axion Dark Matter from Higgs Inflation with an Intermediate H∗
Axion dark matter from Higgs inflation with an intermediate H∗ Tommi Tenkanena and Luca Visinellib;c;d aDepartment of Physics and Astronomy, Johns Hopkins University, 3400 N. Charles Street, Baltimore, MD 21218, USA bDepartment of Physics and Astronomy, Uppsala University, L¨agerhyddsv¨agen1, 75120 Uppsala, Sweden cNordita, KTH Royal Institute of Technology and Stockholm University, Roslagstullsbacken 23, 10691 Stockholm, Sweden dGravitation Astroparticle Physics Amsterdam (GRAPPA), Institute for Theoretical Physics Amsterdam and Delta Institute for Theoretical Physics, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands E-mail: [email protected], [email protected], [email protected] Abstract. In order to accommodate the QCD axion as the dark matter (DM) in a model in which the Peccei-Quinn (PQ) symmetry is broken before the end of inflation, a relatively low scale of inflation has to be invoked in order to avoid bounds from DM isocurvature 9 fluctuations, H∗ . O(10 ) GeV. We construct a simple model in which the Standard Model Higgs field is non-minimally coupled to Palatini gravity and acts as the inflaton, leading to a 8 scale of inflation H∗ ∼ 10 GeV. When the energy scale at which the PQ symmetry breaks is much larger than the scale of inflation, we find that in this scenario the required axion mass for which the axion constitutes all DM is m0 . 0:05 µeV for a quartic Higgs self-coupling 14 λφ = 0:1, which correspond to the PQ breaking scale vσ & 10 GeV and tensor-to-scalar ratio r ∼ 10−12. Future experiments sensitive to the relevant QCD axion mass scale can therefore shed light on the physics of the Universe before the end of inflation. -
Modified Newtonian Dynamics, an Introductory Review
Modified Newtonian Dynamics, an Introductory Review Riccardo Scarpa European Southern Observatory, Chile E-mail [email protected] Abstract. By the time, in 1937, the Swiss astronomer Zwicky measured the velocity dispersion of the Coma cluster of galaxies, astronomers somehow got acquainted with the idea that the universe is filled by some kind of dark matter. After almost a century of investigations, we have learned two things about dark matter, (i) it has to be non-baryonic -- that is, made of something new that interact with normal matter only by gravitation-- and, (ii) that its effects are observed in -8 -2 stellar systems when and only when their internal acceleration of gravity falls below a fix value a0=1.2×10 cm s . Being completely decoupled dark and normal matter can mix in any ratio to form the objects we see in the universe, and indeed observations show the relative content of dark matter to vary dramatically from object to object. This is in open contrast with point (ii). In fact, there is no reason why normal and dark matter should conspire to mix in just the right way for the mass discrepancy to appear always below a fixed acceleration. This systematic, more than anything else, tells us we might be facing a failure of the law of gravity in the weak field limit rather then the effects of dark matter. Thus, in an attempt to avoid the need for dark matter many modifications of the law of gravity have been proposed in the past decades. The most successful – and the only one that survived observational tests -- is the Modified Newtonian Dynamics. -
Supersymmetric Dark Matter Candidates in Light of Constraints from Collider and Astroparticle Observables
THESE` Pour obtenir le grade de DOCTEUR DE L’UNIVERSITE´ DE GRENOBLE Specialit´ e´ : Physique Theorique´ Arretˆ e´ ministeriel´ : 7 aoutˆ 2006 Present´ ee´ par Jonathan DA SILVA These` dirigee´ par Genevieve` BELANGER´ prepar´ ee´ au sein du Laboratoire d’Annecy-le-Vieux de Physique Theorique´ (LAPTh) et de l’Ecole´ Doctorale de Physique de Grenoble Supersymmetric Dark Matter candidates in light of constraints from collider and astroparticle observables These` soutenue publiquement le 3 juillet 2013, devant le jury compose´ de : arXiv:1312.0257v1 [hep-ph] 1 Dec 2013 Dr. Rohini GODBOLE Professeur, CHEP Bangalore, Inde, Presidente´ Dr. Farvah Nazila MAHMOUDI Maˆıtre de Conferences,´ LPC Clermont, Rapporteur Dr. Ulrich ELLWANGER Professeur, LPT Orsay, Rapporteur Dr. Celine´ BŒHM Charge´ de recherche, Durham University, Royaume-Uni, Examinatrice Dr. Anupam MAZUMDAR Professeur, Lancaster University, Royaume-Uni, Examinateur Dr. Genevieve` BELANGER´ Directeur de Recherche, LAPTh, Directeur de these` A meus av´os. Contents Acknowledgements - Remerciements vii List of Figures xi List of Tables xvii List of Abbreviations xix List of Publications xxiii Introduction1 I Status of particle physics and cosmology ... and beyond5 1 From the infinitely small : the Standard Model of particle physics ...7 1.1 Building of the model : gauge sector . .8 1.2 Matter sector . 10 1.2.1 Leptons . 10 1.2.2 Quarks . 12 1.3 The Higgs mechanism . 13 1.4 Full standard picture . 16 1.5 Successes of the SM . 18 1.6 SM issues . 19 1.6.1 Theoretical problems . 19 1.6.2 Experimental discrepancies . 20 1.6.3 Cosmological connexion . 22 2 ... To the infinitely large : the Lambda Cold Dark Matter model 23 2.1 Theoretical framework . -
An Introduction to Loop Quantum Gravity with Application to Cosmology
DEPARTMENT OF PHYSICS IMPERIAL COLLEGE LONDON MSC DISSERTATION An Introduction to Loop Quantum Gravity with Application to Cosmology Author: Supervisor: Wan Mohamad Husni Wan Mokhtar Prof. Jo~ao Magueijo September 2014 Submitted in partial fulfilment of the requirements for the degree of Master of Science of Imperial College London Abstract The development of a quantum theory of gravity has been ongoing in the theoretical physics community for about 80 years, yet it remains unsolved. In this dissertation, we review the loop quantum gravity approach and its application to cosmology, better known as loop quantum cosmology. In particular, we present the background formalism of the full theory together with its main result, namely the discreteness of space on the Planck scale. For its application to cosmology, we focus on the homogeneous isotropic universe with free massless scalar field. We present the kinematical structure and the features it shares with the full theory. Also, we review the way in which classical Big Bang singularity is avoided in this model. Specifically, the spectrum of the operator corresponding to the classical inverse scale factor is bounded from above, the quantum evolution is governed by a difference rather than a differential equation and the Big Bang is replaced by a Big Bounce. i Acknowledgement In the name of Allah, the Most Gracious, the Most Merciful. All praise be to Allah for giving me the opportunity to pursue my study of the fundamentals of nature. In particular, I am very grateful for the opportunity to explore loop quantum gravity and its application to cosmology for my MSc dissertation. -
Accelerators and Beams
Accelerators AND Beams TOOLS Of DiSCOVERy anD innOVATION 4th Edition Published by the Division of Physics of Beams of the American Physical Society Accelerators AND Beams Introduction Why care about accelerators? .................................. 1 What are accelerators for? ..................................... 2 What is an accelerator? ........................................ 3 The invention of particle accelerators. ........................... 4 How accelerators work ......................................... 6 Applications of accelerators .................................... 8 Advancing the frontiers of knowledge ........................... 9 Accelerators for diagnosing illness and fighting cancer ............ 10 Accelerators to beat food-borne illness ......................... 11 An accelerator makes our band-aids safe ........................ 12 Accelerators and national security .............................. 13 Accelerators validate nuclear weapons readiness ................ 14 Beams of light from beams of particles .......................... 15 Accelerators energize a new kind of laser ........................ 18 Free-electron laser applications ................................. 19 Accelerators for improving materials’ surfaces ................... 20 Accelerator-based neutron science yields payoffs ................ 21 Multiple uses for portable accelerators ......................... 22 Accelerators boost international cooperation .................... 23 Why is an accelerator under the Louvre museum? ................ 24 Accelerators