Muon Physics: a Pillar of the Standard Model
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On the Mass Spectrum of Exotic Protonium Atom in Oscillator Representation Method
International Journal of Advanced Science and Technology Vol.74 (2015), pp.43-48 http://dx.doi.org/10.14257/ijast.2015.74.05 On the Mass Spectrum of Exotic Protonium Atom in Oscillator Representation Method Arezu Jahanshir Assistant professor and faculty member of Bueinzahra Technical University, Iran [email protected] Abstract In the given paper one determines the constituent mass of the bound state and binding energy of hadronic exotic system, according to the basis investigation of the asymptotically behavior of the loop function of scalar particles in the external electromagnet field are analytically determined exploration of these states through relativistic and non-perturbative corrections. It is shown that, the mass spectrum of a relativistic bound state of protonium consisting from proton and anti-proton is differing from a mass of initial particles. Keywords: protonium, constituent mass, Hamiltonian, Green function, scalar particles 1. Introduction All of theoretical high energy physician by using mathematical methods and new theories try to understand how bound state arise in the formalism of quantum field theory and to work out effective methods to calculate all characteristics of these bound states, especially their masses, binding energy and spin interactions. The analysis of a bound state is difficult when the interaction have to be considered as relativistic, i.e. when they travel at speeds considerably near the "c". The theoretical criterion is that the coupling constant should be strong [1-6] and masses of intermediate particles gluons in quantum chromodynamic should be big in comparison with masses of constituents. New importance to the exotic hadronic bound state physics was given by the development of quantum chromodynamic, the modern theory of strong interactions. -
Muon Decay 1
Muon Decay 1 LIFETIME OF THE MUON Introduction Muons are unstable particles; otherwise, they are rather like electrons but with much higher masses, approximately 105 MeV. Radioactive nuclear decays do not release enough energy to produce them; however, they are readily available in the laboratory as the dominant component of the cosmic ray flux at the earth’s surface. There are two types of muons, with opposite charge, and they decay into electrons or positrons and two neutrinos according to the rules + + µ → e νe ν¯µ − − µ → e ν¯e νµ . The muon decay is a radioactiveprocess which follows the usual exponential law for the probability of survival for a given time t. Be sure that you understand the basis for this law. The goal of the experiment is to measure the muon lifetime which is roughly 2 µs. With care you can make the measurement with an accuracy of a few percent or better. In order to achieve this goal in a conceptually simple way, we look only at those muons that happen to come to rest inside our detector. That is, we first capture a muon and then measure the elapsed time until it decays. Muons are rather penetrating particles, they can easily go through meters of concrete. Nevertheless, a small fraction of the muons will be slowed down and stopped in the detector. As shown in Figure 1, the apparatus consists of two types of detectors. There is a tank filled with liquid scintillator (a big metal box) viewed by two photomultiplier tubes (Left and Right) and two plastic scintillation counters (flat panels wrapped in black tape), each viewed by a photomul- tiplier tube (Top and Bottom). -
Muon Neutrino Mass Without Oscillations
The Distant Possibility of Using a High-Luminosity Muon Source to Measure the Mass of the Neutrino Independent of Flavor Oscillations By John Michael Williams [email protected] Markanix Co. P. O. Box 2697 Redwood City, CA 94064 2001 February 19 (v. 1.02) Abstract: Short-baseline calculations reveal that if the neutrino were massive, it would show a beautifully structured spectrum in the energy difference between storage ring and detector; however, this spectrum seems beyond current experimental reach. An interval-timing paradigm would not seem feasible in a short-baseline experiment; however, interval timing on an Earth-Moon long baseline experiment might be able to improve current upper limits on the neutrino mass. Introduction After the Kamiokande and IMB proton-decay detectors unexpectedly recorded neutrinos (probably electron antineutrinos) arriving from the 1987A supernova, a plethora of papers issued on how to use this happy event to estimate the mass of the neutrino. Many of the estimates based on these data put an upper limit on the mass of the electron neutrino of perhaps 10 eV c2 [1]. When Super-Kamiokande and other instruments confirmed the apparent deficit in electron neutrinos from the Sun, and when a deficit in atmospheric muon- neutrinos likewise was observed, this prompted the extension of the kaon-oscillation theory to neutrinos, culminating in a flavor-oscillation theory based by analogy on the CKM quark mixing matrix. The oscillation theory was sensitive enough to provide evidence of a neutrino mass, even given the low statistics available at the largest instruments. J. M. Williams Neutrino Mass Without Oscillations (2001-02-19) 2 However, there is reason to doubt that the CKM analysis validly can be applied physically over the long, nonvirtual propagation distances of neutrinos [2]. -
Progress and Simulations for Intranuclear Neutron-Antineutron 40Ar Transformations in 18 Joshua L
PHYSICAL REVIEW D 101, 036008 (2020) Progress and simulations for intranuclear neutron-antineutron 40Ar transformations in 18 Joshua L. Barrow * The University of Tennessee at Knoxville, Department of Physics and Astronomy, † 1408 Circle Drive, Knoxville, Tennessee 37996, USA ‡ Elena S. Golubeva and Eduard Paryev§ Institute for Nuclear Research, Russian Academy of Sciences, Prospekt 60-letiya Oktyabrya 7a, Moscow 117312, Russia ∥ Jean-Marc Richard Institut de Physique des 2 Infinis de Lyon, Universit´e de Lyon, CNRS-IN2P3–UCBL, 4 rue Enrico Fermi, Villeurbanne 69622, France (Received 10 June 2019; accepted 29 January 2020; published 18 February 2020) With the imminent construction of the Deep Underground Neutrino Experiment (DUNE) and Hyper- Kamiokande, nucleon decay searches as a means to constrain beyond standard model extensions are once again at the forefront of fundamental physics. Abundant neutrons within these large experimental volumes, along with future high-intensity neutron beams such as the European Spallation Source, offer a powerful, high-precision portal onto this physics through searches for B and B − L violating processes such as neutron-antineutron transformations (n → n¯), a key prediction of compelling theories of baryogenesis. With this in mind, this paper discusses a novel and self-consistent intranuclear simulation of this process 40 within 18Ar, which plays the role of both detector and target within the DUNE’s gigantic liquid argon time projection chambers. An accurate and independent simulation of the resulting intranuclear annihilation respecting important physical correlations and cascade dynamics for this large nucleus is necessary to understand the viability of such rare searches when contrasted against background sources such as atmospheric neutrinos. -
Muons: Particles of the Moment
FEATURES Measurements of the anomalous magnetic moment of the muon provide strong hints that the Standard Model of particle physics might be incomplete Muons: particles of the moment David W Hertzog WHEN asked what the most important strange, bottom and top; and six leptons, issue in particle physics is today, my ABORATORY namely the electron, muon and tau- colleagues offer three burning ques- L lepton plus their associated neutrinos. ATIONAL tions: What is the origin of mass? Why N A different set of particles is respon- is the universe made of matter and not sible for the interactions between these equal parts of matter and antimatter? ROOKHAVEN matter particles in the model. The elec- And is there any physics beyond the B tromagnetic interaction that binds elec- Standard Model? trons to nuclei results from the exchange The first question is being addressed of photons, whereas the strong force by a feverish quest to find the Higgs that binds quarks together inside neut- boson, which is believed to be respon- rons, protons and other hadrons is car- sible for the mass of fundamental par- ried by particles called gluons. The ticles. The Tevatron at Fermilab, which third force in the Standard Model – the is currently running, or the Large Had- weak nuclear interaction, which is re- ron Collider at CERN, which is due sponsible for radioactive decay – is car- to start experiments in 2007, should OWMAN ried by the W and Z bosons. B IPP eventually provide the answer to this R Physicists love the Standard Model, question by detecting the Higgs and but they do not like it. -
Exotic Double-Charm Molecular States with Hidden Or Open Strangeness and Around 4.5 ∼ 4.7 Gev
PHYSICAL REVIEW D 102, 094006 (2020) Exotic double-charm molecular states with hidden or open strangeness and around 4.5 ∼ 4.7 GeV † Fu-Lai Wang and Xiang Liu * School of Physical Science and Technology, Lanzhou University, Lanzhou 730000, China and Research Center for Hadron and CSR Physics, Lanzhou University and Institute of Modern Physics of CAS, Lanzhou 730000, China (Received 1 September 2020; accepted 16 October 2020; published 10 November 2020) à In this work, we investigate the interactions between the charmed-strange meson (Ds;Ds )inH-doublet à and the (anti-)charmed-strange meson (Ds1;Ds2)inT-doublet, where the one boson exchange model is adopted by considering the S-D wave mixing and the coupled-channel effects. By extracting the effective ¯ potentials for the discussed HsTs and HsTs systems, we try to find the bound state solutions for the corresponding systems. We predict the possible hidden-charm hadronic molecular states with hidden à ¯ PC 0−− 0−þ à ¯ à strangeness, i.e., the Ds Ds1 þ c:c: states with J ¼ ; and the Ds Ds2 þ c:c: states with PC −− −þ J ¼ 1 ; 1 . Applying the same theoretical framework, we also discuss the HsTs systems. Unfortunately, the existence of the open-charm and open-strange molecular states corresponding to the HsTs systems can be excluded. DOI: 10.1103/PhysRevD.102.094006 ¯ ðÞ I. INTRODUCTION strong evidence to support these Pc states as the ΣcD - – Studying exotic hadronic states, which are very type hidden-charm pentaquark molecules [10 16]. different from conventional mesons and baryons, is an Before presenting our motivation, we first need to give a intriguing research frontier full of opportunities and chal- brief review of how these observed XYZ states were lenges in hadron physics. -
Antiproton–Proton Scattering Experiments with Polarization ( Collaboration) PAX Abstract
Technical Proposal for Antiproton–Proton Scattering Experiments with Polarization ( Collaboration) PAX arXiv:hep-ex/0505054v1 17 May 2005 J¨ulich, May 2005 2 Technical Proposal for PAX Frontmatter 3 Technical Proposal for Antiproton–Proton Scattering Experiments with Polarization ( Collaboration) PAX Abstract Polarized antiprotons, produced by spin filtering with an internal polarized gas target, provide access to a wealth of single– and double–spin observables, thereby opening a new window to physics uniquely accessible at the HESR. This includes a first measurement of the transversity distribution of the valence quarks in the proton, a test of the predicted opposite sign of the Sivers–function, related to the quark dis- tribution inside a transversely polarized nucleon, in Drell–Yan (DY) as compared to semi–inclusive DIS, and a first measurement of the moduli and the relative phase of the time–like electric and magnetic form factors GE,M of the proton. In polarized and unpolarized pp¯ elastic scattering, open questions like the contribution from the odd charge–symmetry Landshoff–mechanism at large t and spin–effects in the extraction | | of the forward scattering amplitude at low t can be addressed. The proposed de- | | tector consists of a large–angle apparatus optimized for the detection of DY electron pairs and a forward dipole spectrometer with excellent particle identification. The design and performance of the new components, required for the polarized antiproton program, are outlined. A low–energy Antiproton Polarizer Ring (APR) yields an antiproton beam polarization of Pp¯ = 0.3 to 0.4 after about two beam life times, which is of the order of 5–10 h. -
Arxiv:1512.01765V2 [Physics.Atom-Ph]
August12,2016 1:27 WSPCProceedings-9.75inx6.5in Antognini˙ICOLS˙3 page 1 1 Muonic atoms and the nuclear structure A. Antognini∗ for the CREMA collaboration Institute for Particle Physics, ETH, 8093 Zurich, Switzerland Laboratory for Particle Physics, Paul Scherrer Institute, 5232 Villigen-PSI, Switzerland ∗E-mail: [email protected] High-precision laser spectroscopy of atomic energy levels enables the measurement of nu- clear properties. Sensitivity to these properties is particularly enhanced in muonic atoms which are bound systems of a muon and a nucleus. Exemplary is the measurement of the proton charge radius from muonic hydrogen performed by the CREMA collaboration which resulted in an order of magnitude more precise charge radius as extracted from other methods but at a variance of 7 standard deviations. Here, we summarize the role of muonic atoms for the extraction of nuclear charge radii, we present the status of the so called “proton charge radius puzzle”, and we sketch how muonic atoms can be used to infer also the magnetic nuclear radii, demonstrating again an interesting interplay between atomic and particle/nuclear physics. Keywords: Proton radius; Muon; Laser spectroscopy, Muonic atoms; Charge and mag- netic radii; Hydrogen; Electron-proton scattering; Hyperfine splitting; Nuclear models. 1. What atomic physics can do for nuclear physics The theory of the energy levels for few electrons systems, which is based on bound- state QED, has an exceptional predictive power that can be systematically improved due to the perturbative nature of the theory itself [1, 2]. On the other side, laser spectroscopy yields spacing between energy levels in these atomic systems so pre- cisely, that even tiny effects related with the nuclear structure already influence several significant digits of these measurements. -
Plasma Physics and Fusion Research Royal Institute of Technology S-100 44 Stockholm Sweden Trita-Pfu-91-05
ISSN 0348-7644 TRITA-PFU-91-05 NEUTRON TIME-OF-FLIGHT COUNTERS AND SPECTROMETERS FOR DIAGNOSTICS OF BURNING FUSION PLASMAS T. Elevant and M. Olsson Research and Training Programme on CONTROLLED THERMONUCLEAR FUSION AND PLASMA PHYSICS (EUR-NFR) PLASMA PHYSICS AND FUSION RESEARCH ROYAL INSTITUTE OF TECHNOLOGY S-100 44 STOCKHOLM SWEDEN TRITA-PFU-91-05 NEUTRON TIME-OF-FLIGHT COUNTERS AND SPECTROMETERS FOR DIAGNOSTICS OF BURNING FUSION PLASMAS T. Elevant and M. Olsson Stockholm, February 1991 Department of Plasma Physics and Fusion Research Royal Institute of Technology 5-100 44 Stockholm, Sweden Neutron Time-of-Flight Counters and Spectrometers for Diagnostics of burning Fusion Plasmas. T. Elevant and M. Olsson. Department of Plasma Physics and Fusion Research, The Royal Institute of Technology, S-10044 Stockholm, Sweden. ABSTRACT Experiment with burning fusion plasmas in tokamaks will place particular requirements on neutron measurements from radiation resistance-, physics-, burn control- and reliability considerations. The possibility to meet these needs by measurements of neutron fluxes and energy spectra by means of time-of-flight techniques are described. Reference counters and spectrometers are proposed and characterized with respect to efficiency, count-rate capabilities, energy resolution and tolerable neutron and y-radiation background levels. The instruments can be used in a neutron camera and are capable to operate in collimated neutron fluxes up to levels corresponding to full nuclear output power in the next generation of experiments. Energy resolutions of the spectrometers enables determination of ion temperatures from 3 [keV] through analysis of the Doppler broadening. Primarily, the instruments are aimed for studies of 14 [MeV] neutrons produced in [d,t]-plasmas but can, after minor modifications, be used for analysis of 2.45 [McV] neutrons produced in [d,d]-plasmas. -
Printed Here
PHYSICAL REVIEW C, VOLUME 66, NUMBER 3 Selected Abstracts from Other Physical Review Journals Abstracts of papers which are published in other Physical Review journals and may be of interest to Physical Review C readers are printed here. The Editors of Physical Review C routinely scan the abstracts of Physical Review D papers. Appropriate abstracts of papers in other Physical Review journals may be included upon request. Supernova neutrinos and the LSND evidence for neutrino oscil- We present a study of inhomogeneous big bang nucleosynthesis lations. Michel Sorel and Janet Conrad, Department of Physics, with emphasis on transport phenomena. We combine a hydrody- Columbia University, New York, New York 10027. ͑Received 15 namic treatment to a nuclear reaction network and compute the light December 2001; published 23 August 2002͒ element abundances for a range of inhomogeneity parameters. We ®nd that shortly after annihilation of electron-positron pairs, Thom- Å The observation of the e energy spectrum from a supernova son scattering on background photons prevents the diffusion of the burst can provide constraints on neutrino oscillations. We derive remaining electrons. Protons and multiply charged ions then tend to formulas for adiabatic oscillations of supernova antineutrinos for a diffuse into opposite directions so that no net charge is carried. Ions variety of 3- and 4-neutrino mixing schemes and mass hierarchies with ZϾ1 get enriched in the overdense regions, while protons which are consistent with the Liquid Scintillation Neutrino Detector diffuse out into regions of lower density. This leads to a second Å →Å ͑LSND͒ evidence for e oscillations. Finally, we explore the burst of nucleosynthesis in the overdense regions at TϽ20 keV, constraints on these models and LSND given by the supernova SN leading to enhanced destruction of deuterium and lithium. -
Explaining Muon G − 2 Data in the Μνssm Arxiv:1912.04163V3 [Hep-Ph]
Explaining muon g 2 data in the µνSSM − Essodjolo Kpatcha∗a,b, Iñaki Lara†c, Daniel E. López-Fogliani‡d,e, Carlos Muñoz§a,b, and Natsumi Nagata¶f aDepartamento de Física Teórica, Universidad Autónoma de Madrid (UAM), Campus de Cantoblanco, 28049 Madrid, Spain bInstituto de Física Teórica (IFT) UAM-CSIC, Campus de Cantoblanco, 28049 Madrid, Spain cFaculty of Physics, University of Warsaw, Pasteura 5, 02-093 Warsaw, Poland dInstituto de Física de Buenos Aires UBA & CONICET, Departamento de Física, Facultad de Ciencia Exactas y Naturales, Universidad de Buenos Aires, 1428 Buenos Aires, Argentina e Pontificia Universidad Católica Argentina, 1107 Buenos Aires, Argentina fDepartment of Physics, University of Tokyo, Tokyo 113-0033, Japan Abstract We analyze the anomalous magnetic moment of the muon g 2 in the µνSSM. − This R-parity violating model solves the µ problem reproducing simultaneously neu- trino data, only with the addition of right-handed neutrinos. In the framework of the µνSSM, light left muon-sneutrino and wino masses can be naturally obtained driven by neutrino physics. This produces an increase of the dominant chargino-sneutrino loop contribution to muon g 2, solving the gap between the theoretical computation − and the experimental data. To analyze the parameter space, we sample the µνSSM using a likelihood data-driven method, paying special attention to reproduce the cur- rent experimental data on neutrino and Higgs physics, as well as flavor observables such as B and µ decays. We then apply the constraints from LHC searches for events with multi-leptons + MET on the viable regions found. They can probe these regions through chargino-chargino, chargino-neutralino and neutralino-neutralino pair pro- duction. -
Relativistic Kinematics of Particle Interactions Introduction
le kin rel.tex Relativistic Kinematics of Particle Interactions byW von Schlipp e, March2002 1. Notation; 4-vectors, covariant and contravariant comp onents, metric tensor, invariants. 2. Lorentz transformation; frequently used reference frames: Lab frame, centre-of-mass frame; Minkowski metric, rapidity. 3. Two-b o dy decays. 4. Three-b o dy decays. 5. Particle collisions. 6. Elastic collisions. 7. Inelastic collisions: quasi-elastic collisions, particle creation. 8. Deep inelastic scattering. 9. Phase space integrals. Intro duction These notes are intended to provide a summary of the essentials of relativistic kinematics of particle reactions. A basic familiarity with the sp ecial theory of relativity is assumed. Most derivations are omitted: it is assumed that the interested reader will b e able to verify the results, which usually requires no more than elementary algebra. Only the phase space calculations are done in some detail since we recognise that they are frequently a bit of a struggle. For a deep er study of this sub ject the reader should consult the monograph on particle kinematics byByckling and Ka jantie. Section 1 sets the scene with an intro duction of the notation used here. Although other notations and conventions are used elsewhere, I present only one version which I b elieveto b e the one most frequently encountered in the literature on particle physics, notably in such widely used textb o oks as Relativistic Quantum Mechanics by Bjorken and Drell and in the b o oks listed in the bibliography. This is followed in section 2 by a brief discussion of the Lorentz transformation.