DOCSLIB.ORG

An Inflaton Candidate in Gauge Mediated Supersymmetry

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
An Inflaton Candidate in Gauge Mediated Supersymmetry CORE An Inflaton Candidate in Gauge Mediated SupersymmetryMetadata, Breakingcitation and similar papers at core.ac.uk Provided by CERN Document Server Micheal Dine(1) and Antonio Riotto(2) (1)Santa Cruz Institute for Particle Physics, University of California, Santa Cruz, CA 95064 (2)NASA/Fermilab Astrophysics Center, Fermilab National Accelerator Laboratory, Batavia, Illinois 60510-0500 (May 15, 1997) Inflation, as currently understood, requires the presence of fields with very flat potentials. Su- persymmetric models in which supersymmetry breaking is communicated by supergravity naturally yield such fields, but the scales are typically not suitable for obtaining both sufficient inflation and a suitable fluctuation spectrum. In the context of recent ideas about gauge mediation, there are new candidates for the inflaton. We present a simple model for slow-rollover inflation where the vacuum energy driving inflation is related to the same F -term responsible for the spectrum of super- symmetric particles in gauge mediated supersymmetry breaking models. The inflaton is identified with field responsible for the generation of the µ-term. This opens the possibility of getting some knowledge about the low-energy supersymmetric theory from measurements of the cosmic microwave background radiation. Gravitinos do not pose a cosmological problem, while the moduli problem is ameliorated. PACS: 98.80.Cq FERMILAB–Pub–97/138-A SCIPP 97/14 hep-ph/yymmnn The existence of an inflationary stage during the evolu- in this latter class of models, those with gauge-mediated tion of the early Universe is usually invoked to solve the supersymmetry breaking (GMSB) [8]. flatness and the horizon problems of the standard big In this paper we would like to follow the minimal prin- bang cosmology [1]. During inflation the energy density ciple that the inflaton field should not be an extra de- is dominated by the vacuum energy and comoving scales gree of freedom inserted ad hoc in some (supersymmet- suffer an rapid growth. As a result, any harmful topo- ric) theory of particle physics just to drive inflation. We logical defects left as remnants after some Grand Unified will argue that this is indeed possible in the framework of phase transition, such as monopoles, are diluted. Quan- GMSB models and show that a successful inflation model tum fluctuations of the inflaton field imprint a nearly may be constructed. The energy density driving infla- scale invariant spectrum of fluctuations on the back- tion may correspond to the F -term responsible for the ground space time metric. These fluctuations may be re- spectrum of the superpartners in the low-energy effective sponsible for the generation of structure formation. How- theory. Moreover, we will be able to identify the inflaton ever, the level of density and temperature fluctuations field with the same scalar responsible for the generation observed in the present Universe, δρ/ρ ∼ 10−5,require of the µ-term present in the effective superpotential of the inflaton potential to be extremely flat. For instance, the minimal supersymmetric standard model (MSSM), in the chaotic inflationary scenario [2] where the inflaton δW ∼ µHU HD. This raises the possibility of someday potential is V = λφ4 and the condensate sits initially connecting a theory which could be tested at accelera- at scales of order of the Planck scale, the dimensionless tors with measurements of the temperature anisotropy self-coupling λ must be of order of 10−13 to be consistent in the cosmic microwave background and related mea- with observations. The inflaton field must be coupled surements of the two-point correlation function! We will to other fields in order to ensure the conversion of the see that in such a picture, one can predict the fundamen- vacuum energy into radiation at the end of inflation, but tal scale of supersymmetry breaking (which will turn out these couplings must be very small otherwise loop cor- to be about 108 GeV). As it stands, our model is not rections to the inflaton potential spoil its flatness. Such completely satisfactory. As in virtually all models of in- flatness is difficult to understand in generic field theories, flation based on supersymmetry, a fine tuning is required but is quite common in supersymmetric theories [3,4]. to obtain a sufficiently small curvature for the potential Supersymmetry, then, might be expected to play a fun- near the origin. This tuning, at the level of a part in 102, damental role during inflation [5], but what this role must ultimately be given some deeper explanation. might be will almost certainly depend on the way in In general, the effective low-energy theory that emerges which supersymmetry is broken. It is usually assumed from GMSB models contains soft SUSY-breaking mass that supersymmetry is broken in a hidden sector and terms for the scalar superpartners which carry informa- then transmitted to observable fields either through grav- tion about the scale and nature of the hidden-sector itational [6] or gauge interactions [7]. The cosmology of theory. Typical soft breaking terms for sfermions re- this latter class of models has only been partially ex- sulting from GMSB models where SUSY is broken at plored. In this paper we will look for inflaton candidates the scale Λ. The magnitude of these terms is given 1 α 2 √ by m ∼ 4π Λ. This has the interesting consequence hSi /Mp ∼ βFX. Notice that we have added the con- 2 that flavour-changing-neutral-current (FCNC) processes stant ∼ FX in such a way that the the cosmological con- are naturallye suppressed in agreement with experimental stant in the true vacuum is zero, V (hSi) = 0. As we will bounds. In the minimal GMSB models, a singlet field X see, it is necessary that α be small, of order 10−2.On acquires a vacuum expactation value (VEV) for both its the other hand, in the framework of supergravity, it is scalar and auxiliary components, hXi and hFX i respec- well-known that there are contributions to the mass of tively and the spectrum for the messangers is rendered particles during inflation of order H from the terms S†S non-supersymmetric. Integrating out the messenger sec- which must be present in the Kahler potential. These tor gives rise to gaugino masses at one loop and scalar can be cancelled by terms of the form S†SX†X.Thisis masses at two loops, with Λ = FX /X. As we shall see, the fine tuning we have alluded to earlier. It is a generic the energy density V0 driving inflation may be identified feature of models based on supersymmetry [10]. One with the F -term responsible for the spectrum of super- positive feature of these models is that the curvature at 2 symmetric particles, V0 ∼ FX . This is one of the key the minimum of the potential is automatically far larger results of our paper. than the curvature near the origin. This is important for Before launching ourselves into the inflationary aspects reheating. of this paper, let us discuss the issue of the generation Around S = 0 we may simplify the potential as of the µ-term in the context of GMSB models. Leurer et al., although in a different context, have suggested a µ- m2 λ V (S) ' V − S2 − S4, (3) term generation which is relevant for us [9]. In addition 0 2 4 to the usual MSSM fields, there is another singlet, S. 2 2 2 2 FX FX As a consequence of discrete symmetries, the coupling where V0 ∼ β F , m ∼ α 2 and λ ∼ 4β 2 .Ifthe X Mp Mp SHUHD is forbidden in the superpotential. There are, S-field starts sufficiently close to the origin the system however, various higher dimension couplings which can may inflate. S rolls very slowly toward S = hSi during drive hSi. In particular, consider terms in the effective inflation. Its potential energy dominates the energy den- Lagrangian of the form sity of the Universe driving a nearly constant expansion rate 1 1 1 d2θ XS2+p + Sm+3 + Sn+1H H p m n U D 8πV(S) 8πV Mp Mp Mp 2 0 Z H (S)= 2 ' 2. (4) 1 3Mp 3Mp + d4θX†XS†S, (1) M 2 p Z In the slow-roll approximation, we may neglect S¨ in the ˙ 0 where M 1.2 1019 GeV is the Planck mass. This equation of motion so that S '−V /3H. This approx- p ' × 0 00 structure can be enforced by discrete symmetries. The imation is consistent as long as V ,V V for S ∼ 0. first and the fourth terms can contribute to the effective Notice that the quadratic and the quartic terms√ in the negative curvature terms to the S potential. For exam- expression (4) become comparable for S∗ ∼ FX .Since ple, if p = m =2,andn= 1, then the µ-term turns this value is much smaller than hSi and all the dynam- √ ics giving rise to density perturbations takes place in the out to be of the order of FX (times powers of coupling constants). vicinity of the origin, we prefer not to neglect the quartic The field S, although very weakly coupled to ordinary term in the rest of our analysis. matter, may play a significant role in cosmology. We will During the slow-roll phase, when S is near to the ori- devote the rest of the paper to explore the cosmological gin, the cosmic scale factor may grow by N(S) e-foldings: implications of such a field and to show that a succes- Se 8π V0 2πV0 full inflationary scenario may be constructed out of the N ' ' M 2 −V 0(S) m2M2 potential for the field S.
Load more

Recommended publications
  • Who Is the Inflaton ?
    View metadata, citation and similar papers at core.ac.uk Who is the Inflaton ? brought to you by CORE provided by CERN Document Server R. Brout Service de Physique Th´eorique, Universit´e Libre de Bruxelles, CP 225, Bvd. du Triomphe, B-1050 Bruxelles, Belgium, (email: [email protected]). It is proposed that the inflaton field is proportional to the fluctuation of the number density of degrees of freedom of the fields of particle physics. These possess cut-off momenta at O (mP lanck), but this fluctuates since the fields propagate in an underlying space-time transplanckian substratum. If the latter is modeled as an instanton fluid in the manner of Hawking's space-time foam, then this identification, in the rough, is equivalent to the inflaton being the fluctuation of the spatial density of instantons. This interpretation is suggested by Volovik's analogy between space-time and the superfluid. (However, unlike for the latter, one cannot argue from the analogy that the cosmological constant vanishes). In our interpretation Linde's phenomenology of inflation takes on added luster in this way to look at things, since inflation and particle production follow quite naturally from familiar physical concepts operating on a "cisplanckian" level. I. INTRODUCTION In his lectures on cosmology at Erice 1999, Professor E. Kolb in extolling the virtues of the inflaton scenario of inflation closed his inspiring lesson with the resounding question : "Who is the inflaton ?" In the foregoing I shall hazard an answer. My intention, in the present paper, is to introduce more a theoretical framework of conjectural character than any quantitative realization.
    [Show full text]
  • Supersymmetry and Inflation
    Supersymmetry and Inflation Sergio FERRARA (CERN – LNF INFN) July 14 , 2015 Fourteenth Marcel Grossmann Meeting, MG14 University of Rome “La Sapienza”, July 12-18 2015 S. Ferrara - MG14, U. Rome "La Sapienza" 1 July 2015 Contents 1. Single field inflation and Supergravity embedding 2. Inflation and Supersymmetry breaking 3. Minimal models for inflation: a. One chiral multiplet (sgoldstino inflation) b. Two chiral multiplets: T (inflaton), S (sgoldstino) 4. R + R2 Supergravity 5. Nilpotent inflation (sgoldstino-less models) 6. Models with two Supersymmetry breaking scales S. Ferrara - MG14, U. Rome "La Sapienza" July 2015 2 We describe approaches to inflaton dynamics based on Supergravity, the combination of Supersymmetry with General Relativity (GR). Nowadays it is well established that inflationary Cosmology is accurately explained studying the evolution of a single real scalar field, the inflaton, in a Friedmann, Lemaître, Robertson, Walker geometry. A fundamental scalar field, which described the Higgs particle, was also recently discovered at LHC, confirming the interpretation of the Standard Model as a spontaneously broken phase (BEH mechanism) of a non-abelian Yang-Mills theory (Brout, Englert, Higgs, 1964). S. Ferrara - MG14, U. Rome "La Sapienza" July 2015 3 There is then some evidence that Nature is inclined to favor, both in Cosmology and in Particle Physics, theories which use scalar degrees of freedom, even if in diverse ranges of energy scales. Interestingly, there is a cosmological model where the two degrees of freedom, inflaton and Higgs, are identified, the Higgs inflation model (Bezrukov, Shaposhnikov, 2008), where a non-minimal coupling 2 h R of the Higgs field h to gravity is introduced.
    [Show full text]
  • Arxiv:2107.01683V1 [Hep-Ph] 4 Jul 2021 Ai Prxmto Nte2 Oe Hog H Higgs-Dilat the field
    Communications in Physics, Vol. 0, No. 0 (0), pp. 1-15 CONSTRAINT ON THE HIGGS-DILATON POTENTIAL VIA WARM INFLATION IN TWO-TIME PHYSICS VO QUOC PHONG AND NGO PHUC DUC LOC Department of Theoretical Physics, University of Science, Ho Chi Minh City, Vietnam Vietnam National University, Ho Chi Minh City, Vietnam Abstract. Within the SP (2, R) symmetry, the Two-time model (2T model) has six dimensions with two dimensions of time and the dilaton field that can be identified as inflaton in a warm inflation scenario with potential of the form ∼ φ4. From that consideration, we derive the range of parameters for the Higgs-Dilaton potential, the coupling constant between Higgs and Dialton − (α) is lager than 1.598 or smaller than 2.13 × 10 7 when the mass of Dilaton is lager than 200 GeV. Therefore, the 2T-model indirectly suggests that extra-dimension can also be a source of inflation. I. Introduction The 2T model [1, 2, 3, 4, 5, 6, 7] could be a well known choice. The model presents us with an unusual vision of time that advances on a plane, i.e., it has two dimensions of time. This model’s spontaneous symmetry breakdown is also different from the SM’s. The 2T physics is a combination of the standard model’s extended theory and the space-time or gravity theory. This theory has proposed expanding the number of spacetime dimensions to represent the whole cosmos, as well as the introduction of dilaton and its properties, for more than a decade (since 2008).
    [Show full text]
  • Prospects for Measurements with Strange Hadrons at Lhcb
    Prospects for measurements with strange hadrons at LHCb A. A. Alves Junior1, M. O. Bettler2, A. Brea Rodr´ıguez1, A. Casais Vidal1, V. Chobanova1, X. Cid Vidal1, A. Contu3, G. D'Ambrosio4, J. Dalseno1, F. Dettori5, V.V. Gligorov6, G. Graziani7, D. Guadagnoli8, T. Kitahara9;10, C. Lazzeroni11, M. Lucio Mart´ınez1, M. Moulson12, C. Mar´ınBenito13, J. Mart´ınCamalich14;15, D. Mart´ınezSantos1, J. Prisciandaro 1, A. Puig Navarro16, M. Ramos Pernas1, V. Renaudin13, A. Sergi11, K. A. Zarebski11 1Instituto Galego de F´ısica de Altas Enerx´ıas(IGFAE), Santiago de Compostela, Spain 2Cavendish Laboratory, University of Cambridge, Cambridge, United Kingdom 3INFN Sezione di Cagliari, Cagliari, Italy 4INFN Sezione di Napoli, Napoli, Italy 5Oliver Lodge Laboratory, University of Liverpool, Liverpool, United Kingdom, now at Universit`adegli Studi di Cagliari, Cagliari, Italy 6LPNHE, Sorbonne Universit´e,Universit´eParis Diderot, CNRS/IN2P3, Paris, France 7INFN Sezione di Firenze, Firenze, Italy 8Laboratoire d'Annecy-le-Vieux de Physique Th´eorique , Annecy Cedex, France 9Institute for Theoretical Particle Physics (TTP), Karlsruhe Institute of Technology, Kalsruhe, Germany 10Institute for Nuclear Physics (IKP), Karlsruhe Institute of Technology, Kalsruhe, Germany 11School of Physics and Astronomy, University of Birmingham, Birmingham, United Kingdom 12INFN Laboratori Nazionali di Frascati, Frascati, Italy 13Laboratoire de l'Accelerateur Lineaire (LAL), Orsay, France 14Instituto de Astrof´ısica de Canarias and Universidad de La Laguna, Departamento de Astrof´ısica, La Laguna, Tenerife, Spain 15CERN, CH-1211, Geneva 23, Switzerland 16Physik-Institut, Universit¨atZ¨urich,Z¨urich,Switzerland arXiv:1808.03477v2 [hep-ex] 31 Jul 2019 Abstract This report details the capabilities of LHCb and its upgrades towards the study of kaons and hyperons.
    [Show full text]
  • JHEP05(2010)010 , 6 − Ing Springer and 10 May 4, 2010 9 : April 19, 2010 − : Tic Inflationary December 3, 2009 : Published Lar Potential, and No S
    Published for SISSA by Springer Received: December 3, 2009 Accepted: April 19, 2010 Published: May 4, 2010 Light inflaton hunter’s guide JHEP05(2010)010 F. Bezrukova and D. Gorbunovb aMax-Planck-Institut f¨ur Kernphysik, P.O. Box 103980, 69029 Heidelberg, Germany bInstitute for Nuclear Research of the Russian Academy of Sciences, 60th October Anniversary prospect 7a, Moscow 117312, Russia E-mail: [email protected], [email protected] Abstract: We study the phenomenology of a realistic version of the chaotic inflationary model, which can be fully and directly explored in particle physics experiments. The inflaton mixes with the Standard Model Higgs boson via the scalar potential, and no additional scales above the electroweak scale are present in the model. The inflaton-to- Higgs coupling is responsible for both reheating in the Early Universe and the inflaton production in particle collisions. We find the allowed range of the light inflaton mass, 270 MeV . mχ . 1.8 GeV, and discuss the ways to find the inflaton. The most promising are two-body kaon and B-meson decays with branching ratios of orders 10−9 and 10−6, respectively. The inflaton is unstable with the lifetime 10−9–10−10 s. The inflaton decays can be searched for in a beam-target experiment, where, depending on the inflaton mass, from several billions to several tenths of millions inflatons can be produced per year with modern high-intensity beams. Keywords: Cosmology of Theories beyond the SM, Rare Decays ArXiv ePrint: 0912.0390 Open Access doi:10.1007/JHEP05(2010)010 Contents 1 Introduction 1 2 The model 3 3 Inflaton decay palette 6 4 Inflaton from hadron decays 10 JHEP05(2010)010 5 Inflaton production in particle collisions 12 6 Limits from direct searches and predictions for forthcoming experiments 14 7 Conclusions 16 A The νMSM extension 16 1 Introduction In this paper we present an example of how (low energy) particle physics experiments can directly probe the inflaton sector (whose dynamics is important at high energies in the very Early Universe).
    [Show full text]
  • Higgs Inflation
    Higgs inflation Javier Rubio Institut fur¨ Theoretische Physik, Ruprecht-Karls-Universitat¨ Heidelberg, Philosophenweg 16, 69120 Heidelberg, Germany —————————————————————————————————————————— Abstract The properties of the recently discovered Higgs boson together with the absence of new physics at collider experiments allows us to speculate about consistently extending the Standard Model of particle physics all the way up to the Planck scale. In this context, the Standard Model Higgs non- minimally coupled to gravity could be responsible for the symmetry properties of the Universe at large scales and for the generation of the primordial spectrum of curvature perturbations seeding structure formation. We overview the minimalistic Higgs inflation scenario, its predictions, open issues and extensions and discuss its interplay with the possible metastability of the Standard Model vacuum. —————————————————————————————————————————— arXiv:1807.02376v3 [hep-ph] 13 Mar 2019 Email: [email protected] 1 Contents 1 Introduction and summary3 2 General framework7 2.1 Induced gravity . .7 2.2 Higgs inflation from approximate scale invariance . .8 2.3 Tree-level inflationary predictions . 11 3 Effective field theory interpretation 14 3.1 The cutoff scale . 14 3.2 Relation between high- and low-energy parameters . 16 3.3 Potential scenarios and inflationary predictions . 17 3.4 Vacuum metastability and high-temperature effects . 21 4 Variations and extensions 22 4.1 Palatini Higgs inflation . 23 4.2 Higgs-Dilaton model . 24 5 Concluding remarks 26 6 Acknowledgments 26 2 1 Introduction and summary Inflation is nowadays a well-established paradigm [1–6] able to explain the flatness, homogene- ity and isotropy of the Universe and the generation of the primordial density fluctuations seeding structure formation [7–10].
    [Show full text]
  • Pos(Leptonphoton2015)030 ∗ [email protected] Speaker
    Rare Decays of Heavy Mesons PoS(LeptonPhoton2015)030 Gaia LANFRANCHI∗ (on behalf of the LHCb collaboration) Laboratori Nazionali di Frascati, INFN E-mail: [email protected] Rare decays of heavy mesons provide some of the most promising approaches for testing the Standard Model with high level of accuracy. In this paper, the status and prospects in the field are reviewed, with a focus on the measurements performed by the LHCb, CMS and ATLAS collaborations at the Large Hadron Collider at CERN. International Symposium on Lepton Photon Interactions at High Energies XXVII International Symposium on Lepton Photon Interactions at High Energies 17-22 August 2015 Ljubljana,University Slovenia of Ljubljana, Slovenia ∗Speaker. c Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). http://pos.sissa.it/ Rare Decays of Heavy Mesons Gaia LANFRANCHI 1. Introduction The Standard Model (SM) of particle physics cannot be the ultimate theory, as it is incomplete and contains too many free parameters, such as the fermion masses and the quark mixing angles. The pattern of these parameters could be governed by a hidden mechanism yet to be discovered, and so the SM would be a low-energy effective theory of a more fundamental theory that would be superseded by a higher energy scale, expected in the TeV region and accessible at the Large Hadron Collider (LHC). This would imply new symmetries, particles, dynamics, and flavor structure (New Physics, NP) that can be discovered either directly or indirectly.
    [Show full text]
  • Higgs Mechanism and Cosmological Constant in N = 1 Supergravity with Inflaton in a Vector Multiplet
    Eur. Phys. J. C (2017) 77:233 DOI 10.1140/epjc/s10052-017-4807-8 Letter Higgs mechanism and cosmological constant in N = 1 supergravity with inflaton in a vector multiplet Yermek Aldabergenov1,a, Sergei V. Ketov1,2,3,b 1 Department of Physics, Tokyo Metropolitan University, Minami-ohsawa 1-1, Hachioji-shi, Tokyo 192-0397, Japan 2 Kavli Institute for the Physics and Mathematics of the Universe (IPMU), The University of Tokyo, Chiba 277-8568, Japan 3 Institute of Physics and Technology, Tomsk Polytechnic University, 30 Lenin Ave., Tomsk 634050, Russian Federation Received: 2 March 2017 / Accepted: 3 April 2017 © The Author(s) 2017. This article is an open access publication Abstract The N = 1 supergravity models of cosmologi- sive vector multiplet were constructed in Ref. [6] by exploit- cal inflation with an inflaton belonging to a massive vector ing the non-minimal self-coupling of a vector multiplet to multiplet and spontaneous SUSY breaking after inflation are supergravity [7]. The supergravity inflationary models [6] reformulated as the supersymmetric U(1) gauge theories of have the single-field scalar potential given by an arbitrary real a massless vector superfield interacting with the Higgs and function squared. Those scalar potentials are always bounded Polonyi chiral superfields, all coupled to supergravity. The from below and allow any desired values of the CMB observ- U(1) gauge sector is identified with the U(1) gauge fields of ables ns and r. However, the minima of the scalar potentials the super-GUT coupled to supergravity, whose gauge group of [6] have a vanishing cosmological constant and a vanish- has a U(1) factor.
    [Show full text]
  • Open String Tachyon Is the Stringy Inflaton
    Open string tachyon is the stringy inflaton Hongsu Kim1 Center for Theoretical Astronomy, Korea Astronomy and Space Science Institute, Daejeon 34055, Republic of Korea Abstract Regarding the current status of the superstring theory, despite its fully devel- oped contents of all interactions in nature, it is no doubt that unfortunately it lacks a well established early universe cosmology content, that is, the inflation- ary universe. In the present work, we would like to address precisely this issue. To be more concrete, we would like to demonstrate that remarkably it is the well established open string tachyon condensation which is essentially equivalent to the stringy inflation that has been missing and hence long-seeking by nearly the entire string community. Keywords: superstring, inflationary universe, open string, tachyon 1. Introduction Ever since the advent of the first string revolution up until the recent de- velopment of the second string revolution, the most disturbing feature of the present superstring theory is that the theory lacks the well established event in the early universe cosmology, that is, the inflationary universe. Put differently, despite the long-seeking effort of the string community, the stringy inflaton that is supposed to drive the early universe inflation has been missing [1]. In the present work, however, we would like to demonstrate that remarkably it is the arXiv:1905.13018v2 [physics.gen-ph] 31 May 2019 well established open string tachyon condensation which, upon coupling to the gravitation, is essentially equivalent to the stringy inflation. That is, unlike [email protected] Preprint submitted to Journal of LATEX Templates June 3, 2019 one's plain conjecture, the unwelcome tachyon in open string theory turns out to be the long-seeking, mysteriously missing stringy inflaton.
    [Show full text]
  • Relic Gravity Waves and 7 Kev Dark Matter from a Gev Scale Inflaton
    Physics Letters B 736 (2014) 494–498 Contents lists available at ScienceDirect Physics Letters B www.elsevier.com/locate/physletb Relic gravity waves and 7 keV dark matter from a GeV scale inflaton ∗ F.L. Bezrukov a,b,c, , D.S. Gorbunov d,e a CERN, CH-1211 Genève 23, Switzerland b Physics Department, University of Connecticut, Storrs, CT 06269-3046, USA c RIKEN-BNL Research Center, Brookhaven National Laboratory, Upton, NY 11973, USA d Institute for Nuclear Research of the Russian Academy of Sciences, Moscow 117312, Russia e Moscow Institute of Physics and Technology, Dolgoprudny 141700, Russia a r t i c l e i n f o a b s t r a c t Article history: We study the mechanism of generation of 7keV sterile neutrino Dark Matter (DM) in the model with Received 1 April 2014 light inflaton χ, which serves as a messenger of scale invariance breaking. In this model the inflaton, Received in revised form 29 July 2014 in addition to providing reheating to the Standard Model (SM) particles, decays directly into sterile Accepted 30 July 2014 neutrinos. The latter are responsible for the active neutrino oscillations via seesaw type I mechanism. Available online 4 August 2014 While the two sterile neutrinos may also produce the lepton asymmetry in the primordial plasma and Editor: A. Ringwald hence explain the baryon asymmetry of the Universe, the third one being the lightest may be of 7 keV and serve as DM. For this mechanism to work, the mass of the inflaton is bound to be light (0.1–1 GeV) and uniquely determines its properties, which allows to test the model.
    [Show full text]
  • Jhep08(2019)147
    Published for SISSA by Springer Received: July 8, 2019 Revised: August 4, 2019 Accepted: August 5, 2019 Published: August 27, 2019 Inflaxion dark matter JHEP08(2019)147 Takeshi Kobayashia;c and Lorenzo Ubaldib;c aInternational Centre for Theoretical Physics, Strada Costiera 11, 34151 Trieste, Italy bSISSA and INFN Sezione di Trieste, Via Bonomea 265, 34136 Trieste, Italy cInstitute for Fundamental Physics of the Universe, Via Beirut 2, 34014 Trieste, Italy E-mail: [email protected], [email protected] Abstract: A new mechanism for producing axion dark matter is proposed. By invoking low-scale inflation and a kinetic mixing between the axion and the inflaton, it is shown that the axion is driven to a field point slightly displaced from the potential minimum, which can give rise to the observed dark matter abundance. In this framework, different combina- tions of the axion and inflaton fields play various cosmological roles, including generating the cosmological perturbations, reheating the universe, and serving as dark matter. The kinetic mixing also relates the dark matter lifetime with the reheating temperature. The mechanism tames axions that would otherwise overdominate the universe, and thus opens up new windows in the axion parameter space, including decay constants at the GUT scale and higher. Keywords: Cosmology of Theories beyond the SM, Effective Field Theories ArXiv ePrint: 1907.00984 Open Access, c The Authors. https://doi.org/10.1007/JHEP08(2019)147 Article funded by SCOAP3. Contents 1 Introduction1 2 Inflaton-axion mixing3 2.1
    [Show full text]
  • The Inflaton Field As a Dark Matter Candidate
    The inflaton field as a dark matter candidate ● Incomplete decay mechanism after inflation: Inflaton coherent oscillations ~ (non-thermal) DM ● Single field models ● Hybrid models ● Inflaton thermal relic M. Bastero-Gil with R. Cerezo and J.G. Rosa (1406.xxxx) Inflation vs Dark Matter Inflation (early period of accelerated expansion) ● Horizon problem ● Flatness problem ● Relics ● Galaxy rotation curves ● CMB anisotropies ● Galaxy clusters ● Gravitational lensing ● Structure formation Dark Matter (massive, neutral, stable particle) Single description? very different energy scales.... Inflation & Reheating V(φ)∼φ2 −3 ρφ∼a dark matter? [Turner'83; Kofman, Linde&Starobinsky'94] drastic but incomplete reduction of ρ + thermal bath (SM) T > T φ RH BBN ρDM −28 ξ0≃ ≃2.4×10 mP nγ 0 Preheating Reheating g2 φ2 χ2 gMφ χ2 parametric resonance decay φ→χ χ not efficient complete decay [Liddle&Ureña-Lopez'06] Possible solutions ● Plasma mass effects ?? [Cardenas'07; Panotopoulos'07] ● Thermal inflation after preheating [Liddle, Pahud & Ureña-Lopez'08] ● Reheating through PBH [Hidalgo, Ureña-Lopez & Liddle'11] ● Non-standard kinetic term [Bose & Majumdar'09; De-Santiago & Cervantes-Cota'11] ● Incomplete (fermionic) decay simpler Incomplete decay mechanism LI∼mf ψ̄ ψ+h φ ψ̄ ψ mf >mφ /2 mψ=∣mf +hφ∣ mψ<mφ /2 stops dynamically Generic single field model 2 mφ 2 h =1,m =10−3 m ,m =0.55 m V(φ)= φ +⋯ φ φ P f φ 2 4 ρφ /mP ρ rad Thermalization annihilations ρφ mP t Γφ≠0 Inflaton-to-entropy ratio n /s φ Ωφ 0 4 mφ nφ Γφ=0 = Ω R0 3 T0 s mP t Parameter space 1.78 0.12 h gR mφ≃52 TeV f 1.49(δ) nφ / s m (gR=no.
    [Show full text]