Collider Signatures of Axino and Gravitino Dark Matter
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Wimps and Machos ENCYCLOPEDIA of ASTRONOMY and ASTROPHYSICS
WIMPs and MACHOs ENCYCLOPEDIA OF ASTRONOMY AND ASTROPHYSICS WIMPs and MACHOs objects that could be the dark matter and still escape detection. For example, if the Galactic halo were filled –3 . WIMP is an acronym for weakly interacting massive par- with Jupiter mass objects (10 Mo) they would not have ticle and MACHO is an acronym for massive (astrophys- been detected by emission or absorption of light. Brown . ical) compact halo object. WIMPs and MACHOs are two dwarf stars with masses below 0.08Mo or the black hole of the most popular DARK MATTER candidates. They repre- remnants of an early generation of stars would be simi- sent two very different but reasonable possibilities of larly invisible. Thus these objects are examples of what the dominant component of the universe may be. MACHOs. Other examples of this class of dark matter It is well established that somewhere between 90% candidates include primordial black holes created during and 99% of the material in the universe is in some as yet the big bang, neutron stars, white dwarf stars and vari- undiscovered form. This material is the gravitational ous exotic stable configurations of quantum fields, such glue that holds together galaxies and clusters of galaxies as non-topological solitons. and plays an important role in the history and fate of the An important difference between WIMPs and universe. Yet this material has not been directly detected. MACHOs is that WIMPs are non-baryonic and Since extensive searches have been done, this means that MACHOS are typically (but not always) formed from this mysterious material must not emit or absorb appre- baryonic material. -
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. -
Dark Energy and Dark Matter
Dark Energy and Dark Matter Jeevan Regmi Department of Physics, Prithvi Narayan Campus, Pokhara [email protected] Abstract: The new discoveries and evidences in the field of astrophysics have explored new area of discussion each day. It provides an inspiration for the search of new laws and symmetries in nature. One of the interesting issues of the decade is the accelerating universe. Though much is known about universe, still a lot of mysteries are present about it. The new concepts of dark energy and dark matter are being explained to answer the mysterious facts. However it unfolds the rays of hope for solving the various properties and dimensions of space. Keywords: dark energy, dark matter, accelerating universe, space-time curvature, cosmological constant, gravitational lensing. 1. INTRODUCTION observations. Precision measurements of the cosmic It was Albert Einstein first to realize that empty microwave background (CMB) have shown that the space is not 'nothing'. Space has amazing properties. total energy density of the universe is very near the Many of which are just beginning to be understood. critical density needed to make the universe flat The first property that Einstein discovered is that it is (i.e. the curvature of space-time, defined in General possible for more space to come into existence. And Relativity, goes to zero on large scales). Since energy his cosmological constant makes a prediction that is equivalent to mass (Special Relativity: E = mc2), empty space can possess its own energy. Theorists this is usually expressed in terms of a critical mass still don't have correct explanation for this but they density needed to make the universe flat. -
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 ). -
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. -
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
Faculty of Mathematics and Natural Sciences Bachelor Thesis University of Groningen Modified Newtonian Dynamics (MOND) and a Possible Microscopic Description Author: Supervisor: L.M. Mooiweer prof. dr. E. Pallante Abstract Nowadays, the mass discrepancy in the universe is often interpreted within the paradigm of Cold Dark Matter (CDM) while other possibilities are not excluded. The main idea of this thesis is to develop a better theoretical understanding of the hidden mass problem within the paradigm of Modified Newtonian Dynamics (MOND). Several phenomenological aspects of MOND will be discussed and we will consider a possible microscopic description based on quantum statistics on the holographic screen which can reproduce the MOND phenomenology. July 10, 2015 Contents 1 Introduction 3 1.1 The Problem of the Hidden Mass . .3 2 Modified Newtonian Dynamics6 2.1 The Acceleration Constant a0 .................................7 2.2 MOND Phenomenology . .8 2.2.1 The Tully-Fischer and Jackson-Faber relation . .9 2.2.2 The external field effect . 10 2.3 The Non-Relativistic Field Formulation . 11 2.3.1 Conservation of energy . 11 2.3.2 A quadratic Lagrangian formalism (AQUAL) . 12 2.4 The Relativistic Field Formulation . 13 2.5 MOND Difficulties . 13 3 A Possible Microscopic Description of MOND 16 3.1 The Holographic Principle . 16 3.2 Emergent Gravity as an Entropic Force . 16 3.2.1 The connection between the bulk and the surface . 18 3.3 Quantum Statistical Description on the Holographic Screen . 19 3.3.1 Two dimensional quantum gases . 19 3.3.2 The connection with the deep MOND limit . -
Review of Cold Dark Matter in Astrophysics. Content: Preliminaries: Einstein Equation of Hubble Expansion
J. Steinberger Nov. 2004 Review of Cold Dark Matter in Astrophysics. Content: Preliminaries: Einstein equation of Hubble expansion. Big Bang Nucleo Synthesis. Formation of CDM “Halos” Galactic rotation curves. Measurement of Ωm using x-ray measurements of galaxy clusters. Measurement of Ωm using gravitational lensing. Why neutralinos are hopeful candidates for CDM. 1. Astrophysical preliminaries; Einstein-Friedman equation for a homogeneous universe. Definition of Ωm . Metric of homogeneous universe. a is the scale, x, y and z are “comoving” coordinates, that is, they do not change with the expansion of the universe: ds2 = dt2 + a(t)2(dx2 + dy2 + dz2) Einstein (Friedmann) equation for homogeneous universe: H(t) ≡ ((da/dt)/a)2 = 8πG/3*ρ(t) + Λ , where H is the hubble expansion parameter, ρ is the energy density and Λ is the “cosmological constant”. For relativistic matter, that is kT >> mc2, the variation of ρ with a is as a-4, 4 ρrad = ρrad,0(a0/a) . Subscript zero, here and in the following, refers to the present universe. For nonrelativistic matter, that is kT << mc2, the variation of ρ with a is as a- 3 3 , ρm = ρm,0(a0/a) . Only in recent times, that is for a0/a < ≈ 2, has the cosmological constant term become important; before it was negligible. In the early universe the energy density was dominated by radiation, now it is dominated by non relativistic matter. After cold matter domination, 2 2 3 H(t) = H0 (Ωm(a0/a(t)) + ΩΛ); Ωm+ΩΛ = 1. Ωm is the sum of baryonic matter and cold dark matter: Ωm = Ωb + Ωcdm. -
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. -
Status and Physics of the Ship Experiment at CERN TAUP 2017 – Snolab
Status and Physics of the SHiP experiment at CERN TAUP 2017 { Snolab Daniel Bick July 26, 2017 D. Bick (UHH) TAUP 2017: SHiP July 26, 2017 1 / 15 Physics Motivation SM very successful, however. Strong Evidence for BSM Physics • Neutrino masses and oscillations • The nature of non-baryonic Dark Matter • Excess of matter over antimatter in the Universe • Cosmic inflation of the Universe Shortcoming of Theory • Gap between Fermi and Planck scales • Dark Energy • Connection to gravity • ... New/extended models needed new particles ) D. Bick (UHH) TAUP 2017: SHiP July 26, 2017 2 / 15 Where to Find New Physics • Why haven't we seen these new particles, yet? • Too heavy or too weakly interacting Image: CERN Courier 2/2016 D. Bick (UHH) TAUP 2017: SHiP July 26, 2017 3 / 15 How to Explore Hidden Sector? • Phenomenologies of hidden sector models share a number of unique and common physics features Models Final States Neutrino portal, HNL, SUSY neutralino `±π∓, `±K∓, `±ρ∓ Vector, scalar, axion portals, SUSY sgoldstino e+e−, µ+µ− Vector, scalar, axion portals, SUSY sgoldstino π+π−, K+K− Neutrino portal, HNL, SUSY neutralino, axino `+`−ν • Production through meson decays (π, K, D, B) • Production and decay rates are strongly suppressed relative to SM • Production branching ratios (10−10) O • Long-lived objects (µs) O • Travel unperturbed through ordinary matter D. Bick (UHH) TAUP 2017: SHiP July 26, 2017 4 / 15 νMSM Minimal approach, extends SM by three neutral particles ! T.Asaka, M.Shaposhnikov PLB 620 (2005) 17 Three generations of fermoins, spin -
Dark Matter Theory and Fermi
Dark Matter Theory and Fermi Pearl Sandick the University of Texas at Austin Dark Matter Kowalski et al. (2008) WMAP Clowe et al. (2006) ● ΩDM= 0.233 ± 0.0013 Komatsu et al. (2009) ● It's non-baryonic (BBN+CMB, structure formation). ● It's stable or very long-lived. ● It's not charged (heavy isotope abundances). ● It's largely non-relativistic (cold). Pearl Sandick, UT Austin What could it be? ●Standard Model particles? Weakly ✔ No cold DM in the SM! Interacting Massive (Neutrinos are HOT DM) Particles ● Beyond the SM: ● axions, sterile neutrinos, SUSY particles (LSP = neutralino, gravitino, axino, or sneutrino), Kaluza Klein states (LKP), Little Higgs heavy photons (LTP) or scalars, mirror matter, WIMPzillas, solitons (Q-balls)... Pearl Sandick, UT Austin Weak Scale in Cosmology 1. New (heavy) particle χ in thermal equilibrium: 1 2 χ χ ⇄ f f 2. Universe expands 3 and cools: χ χ ⇄ f f 3. χ's “freeze out” χ χ ⇄ f f Jungman, Kamionkowski and Griest, PR 1996 Pearl Sandick, UT Austin Weak Scale in Cosmology Expansion and annihilation 1 compete to determine the 2 number density: 3 Stable matter with GeV-TeV mass and weak-scale interaction strength yield Ωh2 ~ 0.1 Jungman, Kamionkowski and Griest, PR 1996 Pearl Sandick, UT Austin What could it be? ● Standard ModelTheories particles? that address the shortcomingsWeakly of ✔ No cold DMthe in Standardthe SM! Model involve new physics Interacting at the weak scale, and therefore addressMassive (Neutrinos are HOT DM) the dark matter puzzle, as well.Particles ● Beyond the SM: ● axions, sterile neutrinos, SUSY particles (LSP = neutralino, gravitino, axino, or sneutrino), Kaluza Klein states (LKP), Little Higgs heavy photons (LTP) or scalars, mirror matter, WIMPzillas, solitons (Q-balls)..