88 research outputs found
Void pattern fluctuation in p-AgBr interactions at 400 GeV/c
The event-by-event fluctuation of hadronic patterns is investigated by finding a measure of the non-hadronic regions, the voids, for the experimental data of p-AgBr interactions at 400 GeV/c considering the anisotropy of phase space. Two moments of the event-to-event fluctuation of voids, <Gq> and Sq have been calculated as defined by R. C. Hwa and Q. H. Zhang to quantify the dependence of the voids on the bin sizes. The results suggest that no quark-hadron phase transition of second order have taken place for p-AgBr interactions at 400 GeV/c. The result have been compared with the result of VENUS generated data
Comparative Multi Fractal De-trended Fluctuation Analysis of heavy ion interactions at a few GeV to a few hundred GeV
We have studied the multifractality of pion emission process in 16O-AgBr
interactions at 2.1AGeV & 60AGeV, 12CAgBr &24Mg-AgBr interactions at 4.5AGeV
and 32S-AgBr interactions at 200AGeV using Multifractal Detrended Fluctuation
Analysis (MFDFA) method which is capable of extracting the actual multifractal
property filtering out the average trend of fluctuation. The analysis revels
that the pseudo rapidity distribution of the shower particles is multifractal
in nature for all the interactions i.e. pion production mechanism has in built
multi-scale self-similarity property. We have employed MFDFA method for
randomly generated events for 32S-AgBr interactions at 200 AGeV. Comparison of
expt. results with those obtained from randomly generated data set reveals that
the source of multifractality in our data is the presence of long range
correlation. Comparing the results obtained from different interactions, it may
be concluded that strength of multifractality decreases with projectile mass
for same projectile energy and for a particular projectile it increases with
energy. The values of ordinary Hurst exponent suggest that there is long range
correlation present in our data for all the interactions
Jesu li kolebanja piona u relativističkim i ultrarelativističkim nuklearnim sudarima ovisna o ljestvici?
Fluctuation pattern of pions is investigated in a wide range of projectile energy from 4.5 AGeV (24Mg-AgBr interactions) to 200 AGeV (32S-AgBr interactions). Two-dimensional analysis is performed. To obtain the correct phase-space partition condition considering anisotropy of phase space, we use the concept of Hurst exponent H. The analysis is performed in a rigorous way by fitting one-dimensional factorial moment saturation curves. The effective fluctuation strength aeff is calculated. The study reveals that the fluctuation pattern is scale-dependent at both relativistic and ultrarelativistic energies.Proučavamo kolebanje piona nastalih u sudarima 24Mg-AgBr na 4.5 AGeV i 32SAgBr na 200 AGeV za široko područje energije. Načinili smo dvodimenzijske analize. Zbog anizotropije faznog prostora, primijenili smo Hurstov eksponent H radi postizanja ispravne razdjele faznog prostora. Proveli smo strog račun prilagodbe jednodimenzijskih krivulja zasićenja faktorijalnih momenata. Izračunali smo efektivnu jakost kolebanja αeff. Našli smo ovisnost slike kolebanja o ljestvici za relativističke i ultrarelativističke energije
Ovisnost korelacijskog koeficijenta o veličini intervala faznog prostora u visoko-energijskim međudjelovanjima
We calculated the cumulant moments in order to find the genuine two-particle short-range correlations among the produced pions and also the correlation coefficients in order to quantify the correlations. We studied the cumulant moments and their variation with the pseudorapidity phase-space interval for nucleus-nucleus interactions (24Mg-AgBr at 4.5A GeV and 28Si-AgBr at 14.5A GeV), hadron nucleus interactions (p-AgBr at 800 GeV) and hadron-hadron collisions (p¯p at √ s = 200 GeV and √ s = 900 GeV). The analysis reveals the presence of genuine two-particle short-range correlations among the produced pions in the multi-particle production processes. It is found that the cumulant moments decrease with the increase of the width of the rapidity phase-space intervals. The decrease of cumulant moments with the increase of phase-space interval signifies that the short-range correlation decreases. We investigated the variation of the correlation coefficients in order to study the correlation effects in some more detail in the above mentioned interactions. The nature of variations of the correlation coefficients with the phase-space interval size is different for different types of interactions.Izračunali smo kumulacijske momente radi nalaženja pravih dvočestičnih kratkodosežnih korelacija među proizvedenim pionima te korelacijske koeficijente radi utvrđivanja njihovih iznosa. Proučavamo korelacijske momente i njihove promjene sa širinom intervala pseudorapiditeta u faznom prostoru za međudjelovanja jezgra-jezgra (24Mg-AgBr na 4.5A GeV i 28Si-AgBr na 14.5A GeV), hadronjezgra (p-AgBr na 800 GeV), te u sudarima hadrona (p¯p na √ s = 200 GeV i √ s = 900 GeV). Analize pokazuju prisutnost pravih dvočestičnih kratko-dosežnih korelacija među pionima proizvedenim u mnogočestičnoj tvorbi. Nalazimo smanjenje kumulacijskih momenata s povećanjem širine intervala fazno-prostornog rapiditeta. Pad kumulacijskih momenata s povećanjem fazno-prostornog intervala znači da se smanjuju kratkodosežne korelacije. Također smo istraživali promjene korelacijskih koeficijenata radi podrobnijeg poznavanja korelacijskih efekata u navedenim međudjelovanjima. Narav promjena korelacijskih koeficijenata s veličinom fazno-prostornog intervala različita je u tim međudjelovanjima
Odlamanje u sudarima 16O – AgBr na 60 GeV/n, napomene o modelu isparavanja
We present new data on the target fragment model in 16O - AgBr interactions at 60 GeV/n. The data do not favour the evaporation model; instead, they indicate a preferential backward emission of black tracks.Predstavljamo nove podatke o modelu odlamanja u sudarima 16O – AgBr pri 60 GeV/n. Ti podaci nisu u skladu s modelom isparavanja; umjesto toga nalazi se pretežno izbacivanje unatrag čestica koje daju ”crne” tragove
Azimutalna ovisnost dvopionskih korelacija u relativističkim sudarima teških iona
We have investigated two-pion normalised pseudorapidity correlation for pions from 12C-emulsion interactions at 4.5 A GeV at azimuthal angles φ ≤ 180◦ i φ > 180◦. By comparing experimental correlation values with those of Monte-Carlo simulation values, we found that experimental two-pion normalised pseudorapidity correlations depend on azimuthal angle.Istraživali smo dvopionsku normaliziranu korelaciju pseudorapiditeta za pione nastale u sudarima 12C u emulzijama pri 4.5 A GeV i za azimutalne kutove φ ≤ 180◦ i φ > 180◦. Usporedbom eksperimentalnih korelacija s vrijednostima izračunatim Monte-Carlo simulacijom utvrdili smo ovisnost eksperimentalne dvopionske korelacije pseudorapiditeta o azimutu
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