The capability to predict the parameters of an SEP event such as its onset, peak flux, and duration is critical to assessing any potential space weather impact. We present a new flexible modelling ...system simulating the propagation of Solar Energetic Particles (SEPs) from locations near the Sun to any given location in the heliosphere to forecast the SEP flux profiles. SPARX uses an innovative methodology, that allows implementation within an operational framework, to overcome the time constraints of test particle modelling of SEP profiles, allowing the production of near real time SEP nowcasts and forecasts, when paired with appropriate near real time triggers. SPARX has the capability to produce SEP forecasts within minutes of being triggered by observations of a solar eruptive event. The model is based on the test particle approach and is spatially 3D, thus allowing for the possibility of transport in the direction perpendicular to the magnetic field. The model naturally includes the effects of perpendicular propagation due to drifts and drift-induced deceleration. The modelling framework and the way in which parameters of relevance for Space Weather forecasting are obtained are described. The first results from the modelling system are presented. These results demonstrate that corotation and drift of SEP streams play an important role in shaping SEP flux profiles.
Exclusive rho rho production in two-photon collisions involving a single highly virtual photon is studied with data collected at LEP at centre-of-mass energies 89GeV < \sqrt{s} < 209GeV with a total ...integrated luminosity of 854.7pb^-1 The cross section of the process gamma gamma^* -> rho rho is determined as a function of the photon virtuality, Q^2 and the two-photon centre-of-mass energy, Wgg, in the kinematic region: 1.2GeV^2 < Q^2 < 30GeV^2 and 1.1GeV < Wgg < 3GeV.
The velocity of a ˜3GeV neutrino beam is measured by comparing detection times at the near and far detectors of the MINOS experiment, separated by 734 km. A total of 473 far detector neutrino events ...was used to measure (v-c)/c=5.1±2.9×10-5 (at 68% C.L.). By correlating the measured energies of 258 charged-current neutrino events to their arrival times at the far detector, a limit is imposed on the neutrino mass of mν<50MeV/c2 (99% C.L.).
A search for the lightest neutral CP-even and neutral CP-odd Higgs bosons of the Minimal Supersymmetric Standard Model is performed using 216.6 pb-1 of data collected with the L3 detector at LEP at ...centre-of-mass energies between 203 and 209 GeV. No indication of a signal is found. Including our results from lower centre-of-mass energies, lower limits on the Higgs boson masses are set as a function of tan(beta) for several scenarios. For tan(beta) greater than 0.7 they are mh 84.5 GeV and mA 86.3 GeV at 95% confidence level.
The cross section of the process e^+ e^- -> Z \gamma\gamma -> qq~ \gamma \gamma is measured with 215 pb^-1 of data collected with the L3 detector during the final LEP run at centre-of-mass energies ...around 205 GeV and 207 GeV. No deviation from the Standard Model expectation is observed. The full data sample of 713 pb^-1, collected above the Z resonance, is used to constrain the coefficients of anomalous quartic gauge boson couplings to: -0.02 GeV^-2 a_0/\Lambda^2 0.03 GeV^-2 and -0.07 GeV^-2 a_c/\Lambda^2 0.05 GeV^-2, at 95% confidence level.
An overview is given of the study of final state interactions in hadronically decaying W pairs produced in e^+e^--collisions as it is performed by the four LEP experiments. Bose-Einstein correlations ...are investigated by comparing like- with unlike-signed pairs of pions and/or using the mixed event analysis technique. Colour reconnection is examined with a method that compares the particle flow distributions in inter-jet regions.
A statistical analysis of the relationship between solar energetic particles (SEPs) and properties of solar flares and coronal mass ejections (CMEs) is presented. SEP events during solar cycle 23 are ...selected which are associated with solar flares originating on the visible hemisphere of the Sun and at least of magnitude M1. Taking into account all flares and CMEs that occurred during this period, the probability for the occurrence of an SEP event near Earth is determined. A strong rise of this probability is observed for increasing flare intensities, more western locations, larger CME speeds and halo CMEs. The correlations between the proton peak flux and these solar parameters are derived for a low (>10 MeV) and high (>60 MeV) energy range excluding any flux enhancement due to the passage of fast interplanetary shocks. The obtained correlation coefficients are: 0.55+-0.07 (0.63+-0.06) with flare intensity and 0.56+-0.08 (0.40+-0.09) with the CME speed for E>10 MeV (E>60 MeV). For both energy ranges, the correlations with flare longitude and CME width are very small or non-existent. Furthermore, the occurrence probabilities, correlation coefficients and mean peak fluxes are derived in multi-dimensional bins combining the aforementioned solar parameters. The correlation coefficients are also determined in different proton energy channels ranging from 5 to 200 MeV. The results show that the correlation between the proton peak flux and the CME speed decreases with energy, while the correlation with the flare intensity shows the opposite behavior. Furthermore, the correlation with the CME speed is stronger than the correlation with the flare intensity below 15 MeV and becomes weaker above 20 MeV. Excluding the flux enhancements due to interplanetary shocks, only a small but not very significant change is observed in the correlation between the peak flux below 7 MeV and the CME speed.
Results are presented from a study of the structure of high energy hadronic events recorded by the L3 detector at sqrt(s) 192 GeV. The distributions of several event shape variables are compared to ...resummed O(alphaS^2) QCD calculations. We determine the strong coupling constant at three average centre-of-mass energies: 194.4, 200.2 and 206.2 GeV. These measurements, combined with previous L3 measurements at lower energies demonstrate the running of alphaS as expected in QCD and yield alphaS(mZ) = 0.1227 +- 0.0012 +- 0.0058, where the first uncertainty is experimental and the second is theoretical.
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