G.G.G. Massaro
A5105353228- Particle physics theoretical and experimental studies
- High-Energy Particle Collisions Research
- Quantum Chromodynamics and Particle Interactions
- Particle Detector Development and Performance
- Dark Matter and Cosmic Phenomena
- Neutrino Physics Research
- Cosmology and Gravitation Theories
- Computational Physics and Python Applications
- Atomic and Subatomic Physics Research
- Astrophysics and Cosmic Phenomena
- Black Holes and Theoretical Physics
- Nuclear physics research studies
- Particle Accelerators and Free-Electron Lasers
- Medical Imaging Techniques and Applications
- Advanced NMR Techniques and Applications
- Radiation Detection and Scintillator Technologies
- Distributed and Parallel Computing Systems
- Nuclear Physics and Applications
- Optimization and Mathematical Programming
- SAS software applications and methods
- Muon and positron interactions and applications
- Forest, Soil, and Plant Ecology in China
- Radioactive Decay and Measurement Techniques
- Advanced Electrical Measurement Techniques
- Superconducting Materials and Applications
FHNW University of Applied Sciences and Arts
2023
University of Amsterdam
1997-2020
Amsterdam University of the Arts
1996-2020
Queen Mary University of London
2011-2013
National Institute for Subatomic Physics
1995-2013
The University of Adelaide
2013
European Organization for Nuclear Research
1990-2012
University of Freiburg
2012
Lawrence Berkeley National Laboratory
2011
Humboldt-Universität zu Berlin
2000
We report the analysis of spatial energy distribution data for ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\mathrm{hadrons}$ obtained with MARK-J detector at PETRA. define quantity "oblateness" to describe flat shape configuration and three-jet structure which is unambiguously observed first time. Our can be explained by quantum chromodynamic predictions production quark-antiquark pairs accompanied hard noncollinear gluons.
Measurements of the reactions ${e}^{+}+{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{e}^{+}+{e}^{\ensuremath{-}}$, ${\ensuremath{\mu}}^{+}+{\ensuremath{\mu}}^{\ensuremath{-}}$, and ${\ensuremath{\tau}}^{+}+{\ensuremath{\tau}}^{\ensuremath{-}}$ at PETRA energies (${s}^{\frac{1}{2}}=13,17,27.4,30 \mathrm{and} 31.6$ GeV) are reported. The results show that these agree well with predictions quantum electrodynamics thus determining all known charged leptons pointlike particles to a distance...
The results of a high-statistics study inclusive muon spectra at PETRA are reported. Improved mass limits have been obtained for heavy quarks, leptons, and charged Higgs particles. It is shown that the fragmentation properties b quarks c different, with mean variables 〈zb〉=0.75±0.03±0.06, 〈zc〉=0.46±0.02±0.05 average semileptonic branching ratio B C hadrons R(B)=(10.5±1.5±1.3)%, R(C)=(11.5±1.0±1.7)%.Received 22 April 1983DOI:https://doi.org/10.1103/PhysRevLett.51.443©1983 American Physical Society
With use of the MARK-J detector at $\sqrt{s}=34.7$ GeV 21 000 ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}\mathrm{hadron}$ events have been collected. By measurement asymmetry in angular energy correlations strong coupling constant ${\ensuremath{\alpha}}_{s}=0.13\ifmmode\pm\else\textpm\fi{}0.01 (\mathrm{statistical})\ifmmode\pm\else\textpm\fi{}0.02 (\mathrm{systematic})$ is determined, complete second order, and independent fragmentation models QCD cutoff values used.
With a PETRA energy scan in \ensuremath{\le}30-MeV steps, the continuum production of open top quark up to 38.54 GeV is excluded. Over regions from 29.90 38.63 limits are set on product hadronic branching ratio and electronic width ${B}_{h}{\ensuremath{\Gamma}}_{\mathrm{ee}}$ for toponium be less than 2.0 keV at 95% confidence level. By search flavor-changing neutral currents $b$ decay, models without
The measurement of the nonelectromagnetic forward-backward charge asymmetry in reaction e+e−→μ+μ− at s∼34.6 GeV and angular region 0<|cosθ|<0.8 is reported. With a systematic error less than 1%, we observe an (-8.1±2.1)%. This agreement with standard electroweak theory prediction (-7.6±0.6)%. weak-current coupling constants are also reported.Received 30 April 1982DOI:https://doi.org/10.1103/PhysRevLett.48.1701©1982 American Physical Society
Data from the MARK-J detector on reactions e+ep, +p, 7.+7 in center-of- mass energy range 12 to 36.7 GeV are presented.The p, 7. radii shown be &10 '6 cm.A search has been made for production of a new heavy lepton and spin-0 supersymmetric partners muon.95%-confidence-level lower limits 16 charged 15 scalar muon obtained.
We have performed a high-statistics measurement of Bhabha scattering and the production hadrons in electron-positron annihilation at PETRA energies ($12 \mathrm{GeV}<~\sqrt{s}<~36.7 \mathrm{GeV}$). Combining results with measurements ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}$ ${\ensuremath{\tau}}^{+}{\ensuremath{\tau}}^{\ensuremath{-}}$ enables us to compare our electroweak theory. find ${{sin}^{2}\ensuremath{\theta}}_{w}=0.27\ifmmode\pm\else\textpm\fi{}0.08$. This is...
We use the reaction e+e−→hadrons, in Mark J detector at DESY electron-positron collider PETRA, to determine hadronic cross section up 46.78 GeV. The production of a top quark with charge equal (2/3) is excluded 46.6 GeV 95% C.L. observed rise higher energies consistent electroweak prediction for Z0 mass 93 describe some unusual muon inclusive events.Received 27 January 1986DOI:https://doi.org/10.1103/PhysRevD.34.681©1986 American Physical Society
This paper reports the results of a study hadron production in e+e− collisions at c.m. system energies 33, 35, and 35.8 GeV. Production new quark flavor has been sought. The measured values total cross section, thrust distributions, inclusive muon show no evidence for charge-23e near threshold. In addition, during an energy scan region 29.9<~√s<~31.6 GeV, resonance indicating existence bound state composed quarks found.Received 1 April 1980DOI:https://doi.org/10.1103/PhysRevLett.44.1722©1980...
We report on the measurement of reaction ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{e}^{+}{e}^{\ensuremath{-}}$ with a large---solid-angle electromagnetic shower detector at center-of-mass energies $\sqrt{s}=13 \mathrm{and} 17$ GeV. Comparison our results predictions quantum electrodynamics shows excellent agreement in both angular distribution and energy dependence. Values cutoff parameters are also given.
The results are reported of a search for excited muons (${\ensuremath{\mu}}^{*}$) and electrons (${e}^{*}$) stable charged heavy lepton by measurements the ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}\ensuremath{\gamma}$, ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}\ensuremath{\gamma}$, ${\ensuremath{\mu}}^{+}{\ensuremath{\mu}}^{\ensuremath{-}}\ensuremath{\gamma}\ensuremath{\gamma}$,...
We use the reaction e+e−→μ+μ−, in Mark J detector at DESY high-energy e+e− collider PETRA, to test standard electroweak theory and find good agreement. also set limits on parameters of several extended gauge theories.Received 30 May 1985DOI:https://doi.org/10.1103/PhysRevLett.55.665©1985 American Physical Society
We report mass limits on the ${\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{Z}}^{0}$ and \~{}\fi{}}{W}}^{\ifmmode\pm\else\textpm\fi{}}$, supersymmetric partners of ${Z}^{0}$ ${W}^{\ifmmode\pm\else\textpm\fi{}}$, respectively, using MARK-J detector at PETRA. The experimental signatures in both cases are acoplanar lepton pairs with missing energy. For an additional signature is a single energetic lepton. No evidence found for either \~{}\fi{}}{Z}}^{0}({M}_{{\stackrel{\ifmmode...