| 1. |
- Aggarwal, MM, et al.
(författare)
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Centrality dependence of charged-neutral particle fluctuations in 158A (GeVPb)-Pb-208+Pb-208 collisions
- 2003
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 67:4
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Tidskriftsartikel (refereegranskat)abstract
- Results on the study of localized fluctuations in the multiplicity of charged particles and photons produced in 158A GeV/c Pb+Pb collisions are presented for varying centralities. The charged versus neutral particle multiplicity correlations in common phase space regions of varying azimuthal sizes are analyzed by two different methods. Various types of mixed events are constructed to probe fluctuations arising from different sources. The measured results are compared to those from simulations and from mixed events. The comparison indicates the presence of nonstatistical fluctuations in both the charged particle and photon multiplicities in limited azimuthal regions. However, no correlated charged-neutral fluctuations, a possible signature of formation of disoriented chiral condensates, are observed. An upper limit on the production of disoriented chiral condensates is set.
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| 2. |
- Aggarwal, MM, et al.
(författare)
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Event-by-event fluctuations in particle multiplicities and transverse energy produced in 158A GeVPb plus Pb collisions
- 2002
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Ingår i: Physical Review C (Nuclear Physics). - 0556-2813. ; 65:5
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Tidskriftsartikel (refereegranskat)abstract
- Event-by-event fluctuations in the multiplicities of charged particles and photons, and the total transverse energy in 158A GeV Pb+Pb collisions are studied for a wide range of centralities. For narrow centrality bins the multiplicity and transverse energy distributions are found to be near perfect Gaussians. The effect of detector acceptance on the multiplicity fluctuations has been studied and demonstrated to follow statistical considerations. The centrality dependence of the charged particle multiplicity fluctuations in the measured data has been found to agree reasonably well with those obtained from a participant model. However, for photons the multiplicity fluctuations have been found to be lower compared to those obtained from a participant model. The multiplicity and transverse energy fluctuations have also been compared to those obtained from the VENUS event generator.
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| 3. |
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| 4. |
- Aggarwal, MM, et al.
(författare)
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Transverse mass distributions of neutral pions from Pb-208-induced reactions at 158 center dot A GeV
- 2002
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 23:2, s. 225-236
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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| 5. |
- Arias, A.C., et al.
(författare)
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Use of tin oxide thin films as a transparent electrode in PPV based light-emitting diodes
- 2000
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Ingår i: Thin Solid Films. - 0040-6090 .- 1879-2731. ; 371:1, s. 201-206
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Tidskriftsartikel (refereegranskat)abstract
- Tin oxide (TO) thin films, nominally undoped, have been used as electrodes in poly(p-phenylene vinylene) (PPV) based organic electroluminescent devices. The evolution of the crystallinity and the electrical resistance of TO films submitted to the PPV thermal conversion conditions, have been investigated. It has been found that the electrical resistance is decreased whereas the crystallinity of the film is increased. It is shown in this work, that the photoluminescence of PPV converted on top of TO substrates is not as quenched as it is when converted on top of indium-tin oxide (ITO) substrates. The quantum efficiency of light-emitting diode is 0.07% at 17 V forward bias. It is also shown that the work function of TO films is very stable to different cleaning procedures, in contrast with previous results obtained for ITO films.
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| 6. |
- Berggren, Magnus, et al.
(författare)
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Polymer based electrochemical devices for logic functions and paper displays
- 2003
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Here, we report on devices based on patterned thin films of the conducting polymer system poly(3,4-ethylenedioxythiophene) doped with poly(styrene sulphonic acid) (PEDOT:PSS) combined with patterns of solid electrolyte. The key device functionalities base on the updating of the RedOx state of PEDOT. This results in control of the electronic properties of this conjugated polymer, i.e. the conductivity and optical properties are updated. Based on this we have achieved electric current rectifiers, transistors and display cells. Also, matrix addressed displays will be presented. Electrochemical switching is taking place when the oxidation and reduction potentials are overcome respectively. Therefore, these devices operate at voltage levels less then 2 Volts. Low voltage operation is achieved in devices not requiring any extremely narrow dimensions, as is the case for field effect driven devices. All devices reported can or has been made using standard printing techniques on flexible carriers.
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| 7. |
- Georg, U., et al.
(författare)
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Isotope production comparison at ISOLDE with 1 and 1.4 GeV protons
- 2002
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Ingår i: Nuclear Physics A. - 0375-9474. ; 701, s. 137C-143C
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Konferensbidrag (refereegranskat)abstract
- The difference in isotope production between 1 and 1.4 GeV proton projectiles was investigated at ISOLDE/CERN during the year 1999. As target materials uranium carbide, thorium carbide, lead and lanthanum oxide were used and the ratio of the measured production yields for the two different projectile energies were determined for isotopes of the elements francium, mercury, thallium, xenon, cesium, krypton, rubidium and neon. A comparison of these experimental results with the predictions from a two-step reaction model Monte-Carlo code shows good agreement. (C) 2002 Elsevier Science B.V. All rights reserved.
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