371 research outputs found
Transformacije temperature u relativističkoj termodinamici
We analyse the problem of temperature transformation from a historical perspective and attempt to give an answer to the question: "Is the temperature of an object in relativistic motion lower, higher or the same with respect to that of the same object at rest?\u27\u27. We conclude that such a question is ill posed and has no unique answer. We are not claiming a comprehensive review of the subject. In the historical discussion, we give special emphasis to the contribution on the subject by Professor Blanu sa from Zagreb.Analiziramo problem transformacije temperature s povijesnog stajališta i pokušavamo odgovoriti na pitanje: “Da li je temperatura tijela koje se giba relativističkom brzinom niža, viša ili jednaka onoj u sustavu tijela?” Naš je zaključak da je to pitanje pogrešno postavljeno i nema jedan odgovor. Ne tvrdimo da je naše razmatranje cjelovito. U povijesnom odsječku posebno naglašavamo doprinos Profesora D. Blanuše o toj temi
Erraticity of Rapidity Gaps
The use of rapidity gaps is proposed as a measure of the spatial pattern of
an event. When the event multiplicity is low, the gaps between neighboring
particles carry far more information about an event than multiplicity spikes,
which may occur very rarely. Two moments of the gap distrubiton are suggested
for characterizing an event. The fluctuations of those moments from event to
event are then quantified by an entropy-like measure, which serves to describe
erraticity. We use ECOMB to simulate the exclusive rapidity distribution of
each event, from which the erraticity measures are calculated. The dependences
of those measures on the order of of the moments provide single-parameter
characterizations of erraticity.Comment: 10 pages LaTeX + 5 figures p
Reply to Comment of Gazdzicki and Heinz on Strangeness Enhancement in and
The Comment of Gazdzicki and Heinz is flawed because their assumed baryon
stopping power in is inconsistent with data and because they ignored half
the analysis based on the VENUS model. The Comment continues the misleading
presentation of strangeness enhancement by focusing on ratios of integrated
yields. Those ratios discard essential experimental information on the rapidity
dependence of produced and obscure discrepancies between different
data sets. Our conclusion remains that the NA35 minimum bias data on
indicate an anomalous enhancement of central
rapidity strangeness in few nucleon reactions that points to non-equilibrium
dynamics as responsible for strangeness enhancement in nuclear reactions.Comment: revtex file, 6 pages, submitted to Phys. Rev.
Intermittency for coherent and incoherent current ensemble model
We investigate the origin of intermittency for multiparticle distribution in
momentum space, following the idea that there is a kind of power law
distribution of the space-time region of hadron emission. Using the formalism
of current ensamble model to describe boson sources we discuss intermittency
exponents for the coherent and incoherent ( chaotic) particle production
scheme.Comment: 13 pages, latex, no figure
Factorial Moments of Continuous Order
The normalized factorial moments are continued to noninteger values of
the order , satisfying the condition that the statistical fluctuations
remain filtered out. That is, for Poisson distribution for all .
The continuation procedure is designed with phenomenology and data analysis in
mind. Examples are given to show how can be obtained for positive and
negative values of . With being continuous, multifractal analysis is
made possible for multiplicity distributions that arise from self-similar
dynamics. A step-by-step procedure of the method is summarized in the
conclusion.Comment: 15 pages + 9 figures (figures available upon request), Late
Mass Suppression in Octet Baryon Production
There is a striking suppression of the cross section for production of octet
baryons in annihilation, as the mass of the produced hadron
increases. We present a simple parametrization for the fragmentation functions
into octet baryons guided by two input models: the SU(3) flavor symmetry part
is given by a quark-diquark model, and the baryon mass suppression part is
inspired by the string model. We need only eight free parameters to describe
the fragmentation functions for all octet baryons. These free parameters are
determined by a fit to the experimental data of octet baryon production in annihilation. Then we apply the obtained fragmentation functions to
predict the cross section of the octet baryon production in charged lepton DIS
and find consistency with the available experimental data. Furthermore, baryon
production in collisions is suggested to be an ideal domain to check the
predicted mass suppression.Comment: 20 pages, 5 figure
Photoproduction of ϱo on hydrogen with tagged photons between 4 and 6 GeV
We have measured the reaction γp → pπ+π− in the DESY 1 m Streamer Chamber. The dominant ϱo production is analyzed in terms of various models
Charged Particle Production in Proton-, Deuteron-, Oxygen- and Sulphur-Nucleus Collisions at 200 GeV per Nucleon
The transverse momentum and rapidity distributions of net protons and
negatively charged hadrons have been measured for minimum bias proton-nucleus
and deuteron-gold interactions, as well as central oxygen-gold and
sulphur-nucleus collisions at 200 GeV per nucleon. The rapidity density of net
protons at midrapidity in central nucleus-nucleus collisions increases both
with target mass for sulphur projectiles and with the projectile mass for a
gold target. The shape of the rapidity distributions of net protons forward of
midrapidity for d+Au and central S+Au collisions is similar. The average
rapidity loss is larger than 2 units of rapidity for reactions with the gold
target. The transverse momentum spectra of net protons for all reactions can be
described by a thermal distribution with `temperatures' between 145 +- 11 MeV
(p+S interactions) and 244 +- 43 MeV (central S+Au collisions). The
multiplicity of negatively charged hadrons increases with the mass of the
colliding system. The shape of the transverse momentum spectra of negatively
charged hadrons changes from minimum bias p+p and p+S interactions to p+Au and
central nucleus-nucleus collisions. The mean transverse momentum is almost
constant in the vicinity of midrapidity and shows little variation with the
target and projectile masses. The average number of produced negatively charged
hadrons per participant baryon increases slightly from p+p, p+A to central
S+S,Ag collisions.Comment: 47 pages, submitted to Z. Phys.
Lambda and Antilambda polarization from deep inelastic muon scattering
We report results of the first measurements of Lambda and Antilambda
polarization produced in deep inelastic polarized muon scattering on the
nucleon. The results are consistent with an expected trend towards positive
polarization with increasing x_F. The polarizations of Lambda and Antilambda
appear to have opposite signs. A large negative polarization for Lambda at low
positive x_F is observed and is not explained by existing models.A possible
interpretation is presented.Comment: 9 pages, 2 figure
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