Azimuthal Anisotropy of Photon and Charged Particle Emission in Pb+Pb Collisions at 158 A GeV/c

The azimuthal distributions of photons and charged particles with respect to the event plane are investigated as a function of centrality in Pb + Pb collisions at 158 A GeV/c in the WA98 experiment at the CERN SPS. The anisotropy of the azimuthal distributions is characterized using a Fourier analysis. For both the photon and charged particle distributions the first two Fourier coefficients are observed to decrease with increasing centrality. The observed anisotropies of the photon distributions compare well with the expectations from the charged particle measurements for all centralities.Comment: 8 pages and 6 figures. The manuscript has undergone a major revision. The unwanted correlations were enhanced in the random subdivision method used in the earlier version. The present version uses the more established method of division into subevents separated in rapidity to minimise short range correlations. The observed results for charged particles are in agreement with results from the other experiments. The observed anisotropy in photons is explained using flow results of pions and the correlations arising due to the decay of the neutral pion

Multiplicity Distributions and Charged-neutral Fluctuations

Results from the multiplicity distributions of inclusive photons and charged particles, scaling of particle multiplicities, event-by-event multiplicity fluctuations, and charged-neutral fluctuations in 158$\cdot A$ GeV Pb+Pb collisions are presented and discussed. A scaling of charged particle multiplicity as $N_{part}^{1.07\pm 0.05}$ and photons as $N_{part}^{1.12\pm 0.03}$ have been observed, indicating violation of naive wounded nucleon model. The analysis of localized charged-neutral fluctuation indicates a model-independent demonstration of non-statistical fluctuations in both charged particles and photons in limited azimuthal regions. However, no correlated charged-neutral fluctuations are observed.Comment: Talk given at the International Symposium on Nuclear Physics (ISNP-2000), Mumbai, India, 18-22 Dec 2000, Proceedings to be published in Pramana, Journal of Physic

Immunology & Immune System

Increased levels of physical activity are associated with a risk reduction for several neurodegenerative disorders (e.g. Multiple Sclerosis, Parkinsons disease). Moreover, physical exercise is known to improve the physical capacity and to reduce commonlyobserved symptoms, such as motoric, cognitive and a ective impairments. In addition to the ameliorating e ects on speci c symptoms, rst evidence also suggests that physical exercise interventions may counteract and/or alleviate the progress of these diseases.Considering the side effects of drug therapy, exercise interventions represent a promising non-pharmacological supportive treatment option and are therefore increasinglybeinginvestigated in clinical research on neurological diseases.More knowledge about the underlying biological mechanisms is warranted in order to improve tailored exercise programs. However, the reduced accessibility of the central nervous system in humans and problems in the transferability of rodent models complicates research in this eld. Nevertheless, several peripheral markers indicating distinct biological pathways involved in the pathogenesis and progression of neurodegeneration have been revealed to date. Interestingly, these biomarkers have recently been described to be sensitive to exercise stimuli. In this review, we provide an overview of the interaction between potential mechanisms linked to physical exercise and the alleviation of neurodegenerative processes. More precisely, we focus on di erent aspects of exercise-induced impacts on neuronal growth factors, in ammation, blood-brain barrier permeability and the kynurenine pathway.KEY WORDS: Exercise, Physical Activity, Brain, Neurodegeneration, Neurological Disorder

Azimuthal anisotropy of photon and charged particle emissionin 208Pb + 208Pb collisions at 158 ̇ A GeV/c

The azimuthal distributions of photons and charged particles with respect to the event plane are investigated as a function of centrality in Pb + Pb collisions at 158 · A GeV/c in the WA98 experiment at the CERN SPS. The anisotropy of the azimuthal distributions is characterized using a Fourier analysis. For both the photon and charged particle distributions the first two Fourier coefficients are observed to decrease with increasing centrality. The observed anisotropies of the photon distributions compare well with the expectations from the charged particle measurements for all centralities. © Springer-Verlag / Società di Fisica 2005. 208 20

Transverse mass distributions of neutral pions from Pb-208-induced reactions at 158 center dot A GeV

Results on transverse mass spectra of neutral pious measured at central rapidity are presented for impact parameter selected 158-A GeV Pb + Pb-1 and Pb + Nb collisions. The distributions cover the range 0.5 GeV/c(2) less than or equal to MT - Mo less than or equal to 4 GeV/c(2). The change of the spectral shape and the multiplicity with centrality is studied in detail. In going from p+p to semi-peripheral Pb+Pb collisions there is a nuclear enhancement increasing with transverse mass similar to the well known Cronin effect, while for very central collisions this enhancement appears to be weaker than expected