Signature of void probability scaling in multipion production at a few GeV∕nucleon

title: Evidence of different reaction mechanisms for hot and cold events in relativistic heavy-ion interaction
abstract: This paper reports evidence of different reaction mechanisms for two classes of events, ''hot,'' and ''cold,'' in /sup 12/C emulsion at 4.5 (GeV/c)/N observed by Ghosh et al., from a comparison of the transverse-momentum (P/sub T/) distribution with a mixture of two Maxwell-Boltzmann distributions with different temperatures. The hypothesis is substantiated by the significant difference, for ''hot'' and ''cold'' events, in the values of the average number of pions produced, average emission angle of ..cap alpha..-projectile fragments, and ratio of yield of ..cap alpha.. particles to protons as projectile fragments.

title: Multiplicity fluctuations of pions and protons at SPS energy — An in-depth analysis with factorial correlator
abstract: We compute the factorial correlators to study the dynamical fluctuations of pions and a combination of pions and protons (compound multiplicity) in 32S-AgBr interactions at 200 A GeV. The study reveals that for both pion and compound multiplicity the correlated moments increase with the decrease in bin-bin separation D, following a power-law, which suggests the self-similarity of multiplicity fluctuation in each case. The results of the analysis also show a consistency with the prediction of α-model for the existence of intermittency in both cases.

title: MULTIPLICITY DISTRIBUTION AND MULTIPLICITY MOMENT OF BLACK AND GREY PARTICLES IN HIGH ENERGY NUCLEUS–NUCLEUS INTERACTIONS
abstract: In this paper we have studied the multiplicity distribution of black and grey particles emitted from 16O–AgBr interactions at 2.1 AGeV and 60 AGeV. We have also calculated the multiplicity moment up to the fifth order for both the interactions and for both kinds of emitted particles. The variation of multiplicity moment with the order number has been investigated. It is seen that in the case of black particles multiplicity moment up to fourth order remains almost constant as energy increases from 2.1 AGeV to 60 AGeV. Fifth order multiplicity moment increases insignificantly with energy. However in the case of grey particles no such constancy of multiplicity moment with energy of the projectile beam is obtained. Later we have extended our study on the basis of Regge–Mueller approach to find the existence of second order correlation during the emission of black as well as the grey particles. The second Mueller moment is found to be positive and it increases as energy increases in the case of black particles. On the contrary in the case of grey particles the second Mueller moment decreases with energy. It can be concluded that as energy increases correlation among the black particles increases. On the other hand with the increase of energy correlation among the grey particles is found to diminish.

title: Entropy scaling in high-energy nucleus–nucleus interactions
abstract: We studied the multiparticle production in high-energy nucleus–nucleus interactions in terms of particle entropy in 16O–AgBr and 32S–AgBr interactions at 60 A GeV and 200 A GeV, respectively. An approximate scaling behavior of total produced entropy normalized to maximum rapidity in the center of mass frame measured in different rapidity bins has been reported. The scaling behavior is not supported either by the FRITIOF model or by the Monte Carlo simulated events.

title: NON-STATISTICAL FLUCTUATIONS OF PIONS FOR RING- AND JET-LIKE EVENTS AT CERN SPS ENERGY — AN IN-DEPTH ANALYSIS WITH FACTORIAL CORRELATOR
abstract: This study reveals the analysis of ring-like and jet-like events in terms of factorial correlations of 16O–Ag/Br interactions at 60A GeV. The investigation revealed that the correlated moments are found to increase with decreasing bin–bin separation D and follows a power-law which suggests the presence of an intermittent nature of self-similar dynamical fluctuations pattern for ring-like and jet-like events. From the analysis we find that for jet-like events the strength of non-statistical fluctuation is greater than the ring-like and total event set. Jet-like events follow the bin size independence according to α model of intermittency as like total events, whereas ring-like events are not consistent with the prediction of α model of intermittency.

title: Characteristic wino signals in a linear collider from anomaly mediated supersymmetry breaking
abstract: Though the minimal model of anomaly-mediated supersymmetry breaking has been significantly constrained by recent experimental and theoretical work, there are still allowed regions of the parameter space for moderate to large values of $\mathrm{tan}\ensuremath{\beta}.$ We show that these regions will be comprehensively probed in a $\sqrt{s}=1$ TeV ${e}^{+}{e}^{\ensuremath{-}}$ linear collider. Diagnostic signals to this end are studied by zeroing in on a unique and distinct feature of a large class of models in this genre: a neutral W-ino-like lightest supersymmetric particle closely degenerate in mass with a W-ino-like chargino. The pair production processes ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{e}_{L}^{\ifmmode\pm\else\textpm\fi{}}{e}_{L}^{\ensuremath{\mp}},$ ${e}_{R}^{\ifmmode\pm\else\textpm\fi{}}{e}_{R}^{\ensuremath{\mp}},$ ${e}_{L}^{\ifmmode\pm\else\textpm\fi{}}{e}_{R}^{\ensuremath{\mp}},$ $\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\nu}}\ensuremath{\nu}\mathrm{\ifmmode \tilde{}\else \~{}\fi{}\ifmmode \bar{}\else \={}\fi{}},$ ${\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\chi}}}_{1}^{0}{\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\chi}}}_{2}^{0},$ ${\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\chi}}}_{2}^{0}{\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{\ensuremath{\chi}}}_{2}^{0}$ are all considered at $\sqrt{s}=1$ TeV corresponding to the proposed DESY TEV Energy Superconducting Linear Accelerator linear collider in two natural categories of mass ordering in the sparticle spectra. The signals analyzed comprise multiple combinations of fast charged leptons (any of which can act as the trigger) plus displaced vertices ${X}_{D}$ (any of which can be identified by a heavy ionizing track terminating in the detector) and/or associated soft pions with characteristic momentum distributions.

title: Study of single sneutrino production in association with fermion pairs at polarized photon colliders
abstract: We investigate single sneutrino production in the context of R-parity-violating supersymmetry at future ?? linear colliders. The sneutrino is produced in association with fermion pairs and it is shown that its decays into two further fermions will lead to a clean signal. We also discuss possible standard model backgrounds and the effects of beam polarization.

title: Unparticles and Muon Decay
abstract: Recently Georgi has discussed the possible existence of ‘Unparticles’ describable by operators having non-integral scaling dimensions. With the interaction of these with the Standard Model particles being constrained only by gauge and Lorentz symmetries, it affords a new source for lepton flavour violation. Current and future muon decay experiments are shown to be very sensitive to such scenarios.

title: Probing the light neutral Higgs boson scenario of the CP-violating MSSM Higgs sector at the LHC
abstract: In the CP-violating minimal supersymmetric standard model (MSSM), for certain values of the CP-violating phases associated to the universal trilinear couplings (At, Ab) and the gluino mass $(M_{\tilde g})$, e.g., $\Phi_{{CP}} = 60^\circ$ or $90^\circ$, for $
M_{{H^{ + } }} \lesssim 140%
$ GeV and $\tan \beta \sim 2$-5, the lightest Higgs boson mass ($
M_{{H_{1} }} 
$
) is $
 \lesssim 50%
$ GeV. This mass interval is still allowed by results of standard LEP Higgs searches because of a strongly suppressed H1ZZ coupling. However, in the same region of parameter space in which these two conditions occur, the $H_1 H^\mp W^\pm $ coupling is enhanced because the two mentioned sets of couplings satisfy a sum rule. In this paper we probe such a light Higgs scenario at the Large Hadron Collider (LHC) by studying $H^\pm H_1$ associate production, leading to a $
4b + {\ell }^{ \pm } + \not{E}_{{\text{T}}} %
$
 signal. We show that the latter is readily accessible at the CERN hadron collider, upon the application of suitable selection cuts against the standard model (SM) backgrounds. Our parton level Monte Carlo (MC) analysis yields $\sim 15$-45 signal events, completely free of SM background, for ${\cal L} = 10$- 30 fb-1 of accumulated luminosity, after taking into account the overall efficiency for tagging four b-jets.

title: Using Jet Substructure at the LHC to Search for the Light Higgs Bosons of the CP-Violating MSSM
abstract: The CP-violating version of the Minimal Supersymmetric Standard Model (MSSM) is an example of a model where experimental data do not preclude the presence of light Higgs bosons in the range around 10 -- 110 GeV. Such light Higgs bosons, decaying almost wholly to b-bbar pairs, may be copiously produced at the LHC, but would remain inaccessible to conventional Higgs searches because of intractable QCD backgrounds. We demonstrate that a significant number of these light Higgs bosons would be boosted strongly enough for the pair of daughter $b$-jet pairs to appear as a single `fat' jet with substructure. Tagging such jets could extend the discovery potential at the LHC into the hitherto-inaccessible region for light Higgs bosons.