Dark Matter Theory and Fermi
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Axions and Other Similar Particles
1 91. Axions and Other Similar Particles 91. Axions and Other Similar Particles Revised October 2019 by A. Ringwald (DESY, Hamburg), L.J. Rosenberg (U. Washington) and G. Rybka (U. Washington). 91.1 Introduction In this section, we list coupling-strength and mass limits for light neutral scalar or pseudoscalar bosons that couple weakly to normal matter and radiation. Such bosons may arise from the spon- taneous breaking of a global U(1) symmetry, resulting in a massless Nambu-Goldstone (NG) boson. If there is a small explicit symmetry breaking, either already in the Lagrangian or due to quantum effects such as anomalies, the boson acquires a mass and is called a pseudo-NG boson. Typical examples are axions (A0)[1–4] and majorons [5], associated, respectively, with a spontaneously broken Peccei-Quinn and lepton-number symmetry. A common feature of these light bosons φ is that their coupling to Standard-Model particles is suppressed by the energy scale that characterizes the symmetry breaking, i.e., the decay constant f. The interaction Lagrangian is −1 µ L = f J ∂µ φ , (91.1) where J µ is the Noether current of the spontaneously broken global symmetry. If f is very large, these new particles interact very weakly. Detecting them would provide a window to physics far beyond what can be probed at accelerators. Axions are of particular interest because the Peccei-Quinn (PQ) mechanism remains perhaps the most credible scheme to preserve CP-symmetry in QCD. Moreover, the cold dark matter (CDM) of the universe may well consist of axions and they are searched for in dedicated experiments with a realistic chance of discovery. -
Current Perspectives on Dark Matter
Cosmological Signatures of a Mirror Twin Higgs Zackaria Chacko University of Maryland, College Park Curtin, Geller & Tsai Introduction The Twin Higgs framework is a promising approach to the naturalness problem of the Standard Model (SM). In Mirror Twin Higgs models, the SM is extended to include a complete mirror (“twin”) copy of the SM, with its own particle content and gauge groups. The SM and its twin counterpart are related by a discrete Z2 “twin” symmetry. Z2 SMA SMB The mirror particles are completely neutral under the SM strong, weak and electromagnetic forces. Only feel gravity. In Mirror Twin Higgs models, the one loop quadratic divergences that contribute to the Higgs mass are cancelled by twin sector states that carry no charge under the SM gauge groups. Discovery of these states at LHC is therefore difficult. May explain null results. The SM and twin SM primarily interact through the Higgs portal. This interaction is needed for cancellation of quadratic divergences. After electroweak symmetry breaking, SM Higgs and twin Higgs mix. • Higgs couplings to SM states are suppressed by the mixing. • Higgs now has (mixing suppressed) couplings to twin states. A soft breaking of the Z2 symmetry ensures that 퐯B, the VEV of the twin Higgs, is greater than 퐯A, the VEV of the SM Higgs. The mixing angle ~ 퐯A/퐯B. Higgs measurements constrain 퐯A/퐯B ≤ ퟏ/ퟑ. Twin fermions are heavier than SM fermions by a factor of 퐯B/퐯A . Naturalness requires 퐯A/퐯B ≥ ퟏ/ퟓ. (Twin top should not be too heavy.) The Higgs portal interaction has implications for cosmology. -
Signs of Dark Matter May Point to Mirror Matter Candidate 27 April 2010, by Lisa Zyga
Signs of dark matter may point to mirror matter candidate 27 April 2010, by Lisa Zyga (PhysOrg.com) -- Dark matter, which contains the At first, mirror matter may sound a bit like antimatter "missing mass" that's needed to explain why (which is ordinary matter with an opposite charge). galaxies stay together, could take any number of In both theories, the number of known particles forms. The main possible candidates include would double. However, while antimatter interacts MACHOS and WIMPS, but there is no shortage of very strongly with ordinary matter, annihilating itself proposals. Rather, the biggest challenge is finding into photons, mirror matter would interact very some evidence that would support one or more of weakly with ordinary matter. For this reason, some these candidates. Currently, more than 30 physicists have speculated that mirror particles experiments are underway trying to detect a sign of could be candidates for dark matter. Even though dark matter. So far, only two experiments claim to mirror matter would produce light, we would not see have found signals, with the most recent it, and it would be very difficult to detect. observations coming just a month ago. Now, physicist Robert Foot from the University of However, mirror matter would not be impossible to Melbourne has shown that the results of these two detect, and Foot thinks that the DAMA experiment experiments can be simultaneously explained by and the CoGeNT experiment may have detected an intriguing dark matter candidate called mirror mirror matter. In DAMA, scientists observed a piece matter. of sodium iodide, which should generate a photon when struck by a dark matter particle. -
Non–Baryonic Dark Matter V
Non–Baryonic Dark Matter V. Berezinsky1 , A. Bottino2,3 and G. Mignola3,4 1INFN, Laboratori Nazionali del Gran Sasso, 67010 Assergi (AQ), Italy 2Universit`a di Torino, via P. Giuria 1, I-10125 Torino, Italy 3INFN - Sezione di Torino, via P. Giuria 1, I-10125 Torino, Italy 4Theoretical Physics Division, CERN, CH–1211 Geneva 23, Switzerland (presented by V. Berezinsky) The best particle candidates for non–baryonic cold dark matter are reviewed, namely, neutralino, axion, axino and Majoron. These particles are considered in the context of cosmological models with the restrictions given by the observed mass spectrum of large scale structures, data on clusters of galaxies, age of the Universe etc. 1. Introduction (Cosmological environ- The structure formation in Universe put strong ment) restrictions to the properties of DM in Universe. Universe with HDM plus baryonic DM has a Presence of dark matter (DM) in the Universe wrong prediction for the spectrum of fluctuations is reliably established. Rotation curves in many as compared with measurements of COBE, IRAS galaxies provide evidence for large halos filled by and CfA. CDM plus baryonic matter can ex- nonluminous matter. The galaxy velocity distri- plain the spectrum of fluctuations if total density bution in clusters also show the presence of DM in Ω0 ≈ 0.3. intercluster space. IRAS and POTENT demon- There is one more form of energy density in the strate the presence of DM on the largest scale in Universe, namely the vacuum energy described the Universe. by the cosmological constant Λ. The correspond- The matter density in the Universe ρ is usually 2 ing energy density is given by ΩΛ =Λ/(3H0 ). -
Particle - Mirror Particle Oscillations: CP-Violation and Baryon Asymmetry
Particle - Mirror Particle Oscillations: CP-violation and Baryon Asymmetry Zurab Berezhiani Università di L’Aquila and LNGS, Italy 0 CPT at ICTP, Triest, 2-5 July 2008 n − n oscillations etc ... - p. 1/42 Alice & Mirror World Lewis Carroll, "Through the Looking-Glass" ‘Now, if you’ll only attend, Kitty, and not talk so much, I’ll tell you all my ideas about Looking-glass House. There’s the room you can see through the glass – that’s just the same ● Carrol’s Alice... ● Mirror World as our drawing-room, only the things go the other way... the books are something like our ● Mirror Particles ● Interactions books, only the words go the wrong way: I know that, because I’ve held up one of our books to ● B & L violation ● BBN demands the glass, and then they hold up one in the other room. I can see all of it – all but the bit just ● Present Cosmology ● Visible vs. Dark matter behind the fireplace. I do so wish I could see that bit! I want so to know whether they’ve a fire ● B vs. D – Fine Tuning demonstration ● Unification in the winter: you never can tell, you know, unless our fire smokes, and then smoke comes up ● Neutrino Mixing ● See-Saw in that room too – but that may be only pretence, just to make it look as if they had a fire... ● Leptogenesis: diagrams ● Leptogenesis: formulas ‘How would you like to leave in the Looking-glass House, Kitty? I wander if they’d give you milk ● Epochs ● Neutron mixing in there? But perhaps Looking-glass milk isn’t good to drink? Now we come to the passage: ● Neutron mixing ● Oscillation it’s very like our passage as far as you can see, only you know it may be quite on beyond. -
Dark Radiation from the Axino Solution of the Gravitino Problem
21st of July 2011 Dark radiation from the axino solution of the gravitino problem Jasper Hasenkamp II. Institute for Theoretical Physics, University of Hamburg, Hamburg, Germany [email protected] Abstract Current observations of the cosmic microwave background could confirm an in- crease in the radiation energy density after primordial nucleosynthesis but before photon decoupling. We show that, if the gravitino problem is solved by a light axino, dark (decoupled) radiation emerges naturally in this period leading to a new upper 11 bound on the reheating temperature TR . 10 GeV. In turn, successful thermal leptogenesis might predict such an increase. The Large Hadron Collider could en- dorse this opportunity. At the same time, axion and axino can naturally form the observed dark matter. arXiv:1107.4319v2 [hep-ph] 13 Dec 2011 1 Introduction It is a new opportunity to determine the amount of radiation in the Universe from obser- vations of the cosmic microwave background (CMB) alone with precision comparable to that from big bang nucleosynthesis (BBN). Recent measurements by the Wilkinson Mi- crowave Anisotropy Probe (WMAP) [1], the Atacama Cosmology Telescope (ACT) [2] and the South Pole Telescope (SPT) [3] indicate|statistically not significant|the radi- ation energy density at the time of photon decoupling to be higher than inferred from primordial nucleosynthesis in standard cosmology making use of the Standard Model of particle physics, cf. [4,5]. This could be taken as another hint for physics beyond the two standard models. The Planck satellite, which is already taking data, could turn the hint into a discovery. We should search for explanations from particle physics for such an increase in ra- diation [6,7], especially, because other explanations are missing, if the current mean values are accurate. -
Collider Signatures of Axino and Gravitino Dark Matter
2005 International Linear Collider Workshop - Stanford, U.S.A. Collider Signatures of Axino and Gravitino Dark Matter Frank Daniel Steffen DESY Theory Group, Notkestrasse 85, 22603 Hamburg, Germany The axino and the gravitino are extremely weakly interacting candidates for the lightest supersymmetric particle (LSP). We demonstrate that either of them could provide the right amount of cold dark matter. Assuming that a charged slepton is the next-to-lightest supersymmetric particle (NLSP), we discuss how NLSP decays into the axino/gravitino LSP can provide evidence for axino/gravitino dark matter at future colliders. We show that these NLSP decays will allow us to estimate the value of the Peccei–Quinn scale and the axino mass if the axino is the LSP. In the case of the gravitino LSP, we illustrate that the gravitino mass can be determined. This is crucial for insights into the mechanism of supersymmetry breaking and can lead to a microscopic measurement of the Planck scale. 1. INTRODUCTION A key problem in cosmology is the understanding of the nature of cold dark matter. In supersymmetric extensions of the Standard Model, the lightest supersymmetric particle (LSP) is stable if R-parity is conserved [1]. An electrically and color neutral LSP thus appears as a compelling solution to the dark matter problem. The lightest neutralino is such an LSP candidate from the minimal supersymmetric standard model (MSSM). Here we consider two well- motivated alternative LSP candidates beyond the MSSM: the axino and the gravitino. In the following we introduce the axino and the gravitino. We review that axinos/gravitinos from thermal pro- duction in the early Universe can provide the right amount of cold dark matter depending on the value of the reheating temperature after inflation and the axino/gravitino mass. -
Glossary of Terms Absorption Line a Dark Line at a Particular Wavelength Superimposed Upon a Bright, Continuous Spectrum
Glossary of terms absorption line A dark line at a particular wavelength superimposed upon a bright, continuous spectrum. Such a spectral line can be formed when electromag- netic radiation, while travelling on its way to an observer, meets a substance; if that substance can absorb energy at that particular wavelength then the observer sees an absorption line. Compare with emission line. accretion disk A disk of gas or dust orbiting a massive object such as a star, a stellar-mass black hole or an active galactic nucleus. An accretion disk plays an important role in the formation of a planetary system around a young star. An accretion disk around a supermassive black hole is thought to be the key mecha- nism powering an active galactic nucleus. active galactic nucleus (agn) A compact region at the center of a galaxy that emits vast amounts of electromagnetic radiation and fast-moving jets of particles; an agn can outshine the rest of the galaxy despite being hardly larger in volume than the Solar System. Various classes of agn exist, including quasars and Seyfert galaxies, but in each case the energy is believed to be generated as matter accretes onto a supermassive black hole. adaptive optics A technique used by large ground-based optical telescopes to remove the blurring affects caused by Earth’s atmosphere. Light from a guide star is used as a calibration source; a complicated system of software and hardware then deforms a small mirror to correct for atmospheric distortions. The mirror shape changes more quickly than the atmosphere itself fluctuates. -
Light Axinos from Freeze-In: Production Processes, Phase Space Distributions, and Ly-Α Forest Constraints
CTPU-17-25 UT-17-25 Light Axinos from Freeze-in: production processes, phase space distributions, and Ly-α forest constraints Kyu Jung Bae,1 Ayuki Kamada,1 Seng Pei Liew,2 and Keisuke Yanagi3 1Center for Theoretical Physics of the Universe, Institute for Basic Science (IBS), Daejeon 34051, Korea 2Physik-Department, Technische Universit¨atM¨unchen, 85748 Garching, Germany 3Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan (Dated: June 2, 2020) We consider freeze-in production of 7 keV axino dark matter (DM) in the supersymmetric Dine-Fischler-Srednicki-Zhitnitsky (DFSZ) model in light of the 3:5 keV line excess. The warmness of such 7 keV DM produced from the thermal bath, in general, appears in ten- sion with Ly-α forest data, although a direct comparison is not straightforward. This is because the Ly-α forest constraints are usually reported on the mass of the conventional warm dark matter (WDM), where large entropy production is implicitly assumed to occur in the thermal bath after WDM particles decouple. The phase space distribution of freeze-in axino DM varies depending on production processes and axino DM may alleviate the tension with the tight Ly-α forest constraints. By solving the Boltzmann equation, we first obtain the resultant phase space distribution of axinos produced by 2-body decay, 3-body decay, and 2-to-2 scattering, respectively. The reduced collision term and resultant phase space distribution are useful for studying other freeze-in scenarios as well. We then calculate the resultant linear matter power spectra for such axino DM and directly compare them with the linear matter power spectra for the conventional WDM. -
A Short Review of Axion and Axino Parameters
A short review of axion and axino parameters Jihn E. Kim Seoul National University Gwangju Institute of Science and Technology Seattle, 25 April 2012 What can be there beyond SM? New CP? Axions? SUSY? String? 1. Strong CP and axions 2. Axino mass 3. Pseudoscalar boson at 125 GeV ? J E Kim Axion and axino parameters, Seattle, 25 Apr. 2012 2/56 Dark matter observed in the Universe Axion natural sol. of strong CP Supersymmetry natural sol. of the Higgs mass problem All three are related to this talk. J E Kim Axion and axino parameters, Seattle, 25 Apr. 2012 3/56 1. Strong CP and axions Axion is a Goldstone boson arising when the PQ global symmetry is spontaneously broken. PQ symmetry: Wigner-Weyl realization Axion: Nambu-Goldstone realization The axion models have the spontaneous symmetry breaking scale V and the axion decay constant fa which are related by V =NDW fa. Here, I present the general idea on axions and its SUSY partner axino. J E Kim Axion and axino parameters, Seattle, 25 Apr. 2012 4/56 A rough sketch of masses and cross sections. Bosonic DM with collective motion is always CDM. [Kim-Carosi , 2008] J E Kim Axion and axino parameters, Seattle, 25 Apr. 2012 5/56 The cosmic axion density is, 9 12 10 GeV < Fa < {10 GeV ?} Turner (86), Grin et al (07), Giudice-Kolb-Riotto (08), Bae-Huh-K (JCAP 08, [arXiv:0806.0497]): recalculated including the anharmonic term carefully with the new data on light quark masses. It is the basis of using the anthropic argument for a large fa. -
Mirror Matter: Astrophysical Implications
Mirror Matter: Astrophysical implications Zurab Berezhiani Summary Mirror Matter: Astrophysical implications Introduction: Dark Matter from a Parallel World Chapter I: Neutrino - mirror neutrino mixings Zurab Berezhiani Chapter II: neutron { mirror University of L'Aquila and LNGS neutron mixing Chapter IV: n − n0 and Neutron Stars Quarks-2021 , 22-24 June 2021 Contents Mirror Matter: Astrophysical implications Zurab Berezhiani Summary Introduction: Dark Matter from 1 Introduction: Dark Matter from a Parallel World a Parallel World Chapter I: Neutrino - mirror neutrino mixings 2 Chapter I: Neutrino - mirror neutrino mixings Chapter II: neutron { mirror neutron mixing Chapter IV: n − n0 and 3 Chapter II: neutron { mirror neutron mixing Neutron Stars 4 Chapter IV: n n0 and Neutron Stars − Mirror Matter: Astrophysical implications Zurab Berezhiani Summary Introduction: Dark Matter from a Parallel World Introduction Chapter I: Neutrino - mirror neutrino mixings Chapter II: neutron { mirror neutron mixing Chapter IV: n − n0 and Everything can be explained by the Standard Model ! Neutron Stars ... but there should be more than one Standard Models Bright & Dark Sides of our Universe Mirror Matter: Ω 0 05 observable matter: electron, proton, neutron ! Astrophysical B : implications ' ΩD 0:25 dark matter: WIMP? axion? sterile ν? ... Zurab Berezhiani ' ΩΛ 0:70 dark energy: Λ-term? Quintessence? .... Summary ' 3 Introduction: ΩR < 10− relativistic fraction: relic photons and neutrinos Dark Matter from a Parallel World Matter { dark energy coincidence: Ω Ω 0 45, (Ω = Ω + Ω ) Chapter I: M = Λ : M D B Neutrino - mirror 3 ' ρΛ Const., ρM a− ; why ρM /ρΛ 1 { just Today? neutrino mixings ∼ ∼ ∼ Chapter II: Antrophic explanation: if not Today, then Yesterday or Tomorrow. -
Lecture 4: Dark Matter in Galaxies
LectureLecture 4:4: DarkDark MatterMatter inin GalaxiesGalaxies OutlineOutline WhatWhat isis darkdark matter?matter? HowHow muchmuch darkdark mattermatter isis therethere inin thethe Universe?Universe? EvidenceEvidence ofof darkdark mattermatter ViableViable darkdark mattermatter candidatescandidates TheThe coldcold darkdark mattermatter (CDM)(CDM) modelmodel ProblemsProblems withwith CDMCDM onon galacticgalactic scalesscales AlternativesAlternatives toto darkdark mattermatter WhatWhat isis DarkDark Matter?Matter? Dark Matter Luminous Matter FirstFirst detectiondetection ofof darkdark mattermatter FritzFritz ZwickyZwicky (1933):(1933): DarkDark mattermatter inin thethe ComaComa ClusterCluster HowHow MuchMuch DarkDark MatterMatter isis ThereThere inin TheThe Universe?Universe? ΩΩ == ρρ // ρρ Μ Μ c ~2% RecentRecent measurements:measurements: (Luminous) Ω ∼ 0.25, Ω ∼ 0.75 ΩΜ ∼ 0.25, Ω Λ ∼ 0.75 ΩΩ ∼∼ 0.0050.005 Lum ~98% (Dark) HowHow DoDo WeWe KnowKnow ThatThat itit Exists?Exists? CosmologicalCosmological ParametersParameters ++ InventoryInventory ofof LuminousLuminous materialmaterial DynamicsDynamics ofof galaxiesgalaxies DynamicsDynamics andand gasgas propertiesproperties ofof galaxygalaxy clustersclusters GravitationalGravitational LensingLensing DynamicsDynamics ofof GalaxiesGalaxies II Galaxy ≈ Stars + Gas + Dust + Supermassive Black Hole + Dark Matter DynamicsDynamics ofof GalaxiesGalaxies IIII Visible galaxy Observed Vrot Expected R R Dark matter halo Visible galaxy DynamicsDynamics ofof GalaxyGalaxy ClustersClusters Balance