Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The radiative pion decay .pi. .-->. ee−e+.nu. has been observed for the first time with a branching ratio of (3.4 +- 0.5) x 10−9. From the kinematical distribution of 79 events information on the form factors was extracted. The vector form factor F/sub V/ was found to have the same sign as the pion decay constant f/sub .pi./. For the axial-vector form factors the following values have been measured: .gamma. = F/sub A//F/sub V/ = 0.7 +- 0.5 and xi = R/F/sub V/ = 2.3 +- 0.6. This value of .gamma. agrees well with the small positive value of (0.53 +- 0.06) and excludes the large negative value obtained in .pi.+ .-->. e+.nu gamma. experiments. 8 refs. 8 refs.
First Observation of the Decay. Pi. . --]. Ee−e+. Nu. and a Determination of the Form Factors F
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The radiative pion decay .pi. .-->. ee−e+.nu. has been observed for the first time with a branching ratio of (3.4 +- 0.5) x 10−9. From the kinematical distribution of 79 events information on the form factors was extracted. The vector form factor F/sub V/ was found to have the same sign as the pion decay constant f/sub .pi./. For the axial-vector form factors the following values have been measured: .gamma. = F/sub A//F/sub V/ = 0.7 +- 0.5 and xi = R/F/sub V/ = 2.3 +- 0.6. This value of .gamma. agrees well with the small positive value of (0.53 +- 0.06) and excludes the large negative value obtained in .pi.+ .-->. e+.nu gamma. experiments. 8 refs. 8 refs.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
The radiative pion decay .pi. .-->. ee−e+.nu. has been observed for the first time with a branching ratio of (3.4 +- 0.5) x 10−9. From the kinematical distribution of 79 events information on the form factors was extracted. The vector form factor F/sub V/ was found to have the same sign as the pion decay constant f/sub .pi./. For the axial-vector form factors the following values have been measured: .gamma. = F/sub A//F/sub V/ = 0.7 +- 0.5 and xi = R/F/sub V/ = 2.3 +- 0.6. This value of .gamma. agrees well with the small positive value of (0.53 +- 0.06) and excludes the large negative value obtained in .pi.+ .-->. e+.nu gamma. experiments. 8 refs. 8 refs.
High Energy Physics Index
Author:
Publisher:
ISBN:
Category : Particles (Nuclear physics)
Languages : en
Pages : 634
Book Description
Publisher:
ISBN:
Category : Particles (Nuclear physics)
Languages : en
Pages : 634
Book Description
An Experimental Measurement of the Form Factors of the K?L O-->[mu]e[nu] Decay
Energy Research Abstracts
First Observation of the Decay Ks [yields Pi]0[mu]+[mu]− at the NA48 Experiment at CERN.
Author: Maria Teresa Fonseca Martín
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
A search for the KS → pi 0mu+mu- decay was performed by the NA48/1 Collaboration at the CERN SPS accelerator. Six events were found with a background expectation of 0.22+0.18-0.11 in the data collected in 2002 from the high-intensity K S run. The measured branching ratio is: BR( KS → pi0mu+mu -) = [ 2.9+1.5-1.2 (stat) +/- 0.2(syst)] x 10-9, assuming that only vector currents contribute to the matrix element, and a unit form factor.
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
A search for the KS → pi 0mu+mu- decay was performed by the NA48/1 Collaboration at the CERN SPS accelerator. Six events were found with a background expectation of 0.22+0.18-0.11 in the data collected in 2002 from the high-intensity K S run. The measured branching ratio is: BR( KS → pi0mu+mu -) = [ 2.9+1.5-1.2 (stat) +/- 0.2(syst)] x 10-9, assuming that only vector currents contribute to the matrix element, and a unit form factor.
Government Reports Announcements & Index
Nuclear Science Abstracts
Introduction to the Physics of Massive and Mixed Neutrinos
Author: Samoil Bilenky
Publisher: Springer Science & Business Media
ISBN: 3642140424
Category : Science
Languages : en
Pages : 262
Book Description
For many years neutrino was considered a massless particle. The theory of a two-componentneutrino,whichplayedacrucialroleinthecreationofthetheoryof theweakinteraction,isbasedontheassumptionthattheneutrinomassisequalto zero. We now know that neutrinos have nonzero, small masses. In numerous exp- iments with solar, atmospheric, reactor and accelerator neutrinos a new p- nomenon, neutrino oscillations, was observed. Neutrino oscillations (periodic transitionsbetweendifferent?avorneutrinos? ,? ,? )arepossibleonlyifneutrino e ? ? mass-squareddifferencesaredifferentfromzeroandsmalland?avorneutrinosare “mixed”. The discovery of neutrino oscillations opened a new era in neutrino physics: an era of investigation of neutrino masses, mixing, magnetic moments and other neutrino properties. After the establishment of the Standard Model of the el- troweak interaction at the end of the seventies, the discovery of neutrino masses was the most important discovery in particle physics. Small neutrino masses cannot be explained by the standard Higgs mechanism of mass generation. For their explanation a new mechanism is needed. Thus, small neutrino masses is the ?rst signature in particle physics of a new beyond the Standard Model physics. It took many years of heroic efforts by many physicists to discover n- trino oscillations. After the ?rst period of investigation of neutrino oscillations, manychallengingproblemsremainedunsolved.Oneofthemostimportantisthe problem of the nature of neutrinos with de?nite masses. Are they Dirac n- trinos possessing a conserved lepton number which distinguish neutrinos and antineutrinos or Majorana neutrinos with identical neutrinos and antineutrinos? Many experiments of the next generation and new neutrino facilities are now under preparation and investigation. There is no doubt that exciting results are ahead.
Publisher: Springer Science & Business Media
ISBN: 3642140424
Category : Science
Languages : en
Pages : 262
Book Description
For many years neutrino was considered a massless particle. The theory of a two-componentneutrino,whichplayedacrucialroleinthecreationofthetheoryof theweakinteraction,isbasedontheassumptionthattheneutrinomassisequalto zero. We now know that neutrinos have nonzero, small masses. In numerous exp- iments with solar, atmospheric, reactor and accelerator neutrinos a new p- nomenon, neutrino oscillations, was observed. Neutrino oscillations (periodic transitionsbetweendifferent?avorneutrinos? ,? ,? )arepossibleonlyifneutrino e ? ? mass-squareddifferencesaredifferentfromzeroandsmalland?avorneutrinosare “mixed”. The discovery of neutrino oscillations opened a new era in neutrino physics: an era of investigation of neutrino masses, mixing, magnetic moments and other neutrino properties. After the establishment of the Standard Model of the el- troweak interaction at the end of the seventies, the discovery of neutrino masses was the most important discovery in particle physics. Small neutrino masses cannot be explained by the standard Higgs mechanism of mass generation. For their explanation a new mechanism is needed. Thus, small neutrino masses is the ?rst signature in particle physics of a new beyond the Standard Model physics. It took many years of heroic efforts by many physicists to discover n- trino oscillations. After the ?rst period of investigation of neutrino oscillations, manychallengingproblemsremainedunsolved.Oneofthemostimportantisthe problem of the nature of neutrinos with de?nite masses. Are they Dirac n- trinos possessing a conserved lepton number which distinguish neutrinos and antineutrinos or Majorana neutrinos with identical neutrinos and antineutrinos? Many experiments of the next generation and new neutrino facilities are now under preparation and investigation. There is no doubt that exciting results are ahead.
The Fourier Transform and Its Applications
Author: Ronald Newbold Bracewell
Publisher:
ISBN:
Category : Fourier transformations
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category : Fourier transformations
Languages : en
Pages :
Book Description
Introduction to Unconventional Superconductivity
Author: V.P. Mineev
Publisher: CRC Press
ISBN: 9789056992095
Category : Science
Languages : en
Pages : 204
Book Description
Unconventional superconductivity (or superconductivity with a nontrivial Cooper pairing) is believed to exist in many heavy-fermion materials as well as in high temperature superconductors, and is a subject of great theoretical and experimental interest. The remarkable progress achieved in this field has not been reflected in published monographs and textbooks, and there is a gap between current research and the standard education of solid state physicists in the theory of superconductivity. This book is intended to meet this information need and includes the authors' original results.
Publisher: CRC Press
ISBN: 9789056992095
Category : Science
Languages : en
Pages : 204
Book Description
Unconventional superconductivity (or superconductivity with a nontrivial Cooper pairing) is believed to exist in many heavy-fermion materials as well as in high temperature superconductors, and is a subject of great theoretical and experimental interest. The remarkable progress achieved in this field has not been reflected in published monographs and textbooks, and there is a gap between current research and the standard education of solid state physicists in the theory of superconductivity. This book is intended to meet this information need and includes the authors' original results.