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Correlations and fluctuations between produced particles in an ultra-relativistic nuclear collision remain one of the successor to understand the basics of the particle production mechanism. More differential tools like Forward-Backward (FB) correlations between particles from two different phase-space further strengthened our cognizance. We have studied the strength of FB correlations in terms of charged particle multiplicity and summed transverse momentum for proton-proton ($pp$) and proton-lead ($pPb$) collisions at the centre-of-mass energies $\sqrt{s}$ = 13 TeV and $\sqrt{s_{\rm NN}}$ = 5.02 TeV respectively for the EPOS3 simulated events with hydrodynamical evolution of produced particles. Furthermore, the correlation strengths are separately obtained for the particles coming from the core and the corona. FB correlation strengths are examined as a function of psedorapidity gap ($\eta_{gap}$), psedorapidity window-width ($\delta\eta$), centre-of-mass energy ($\sqrt{s}$), minimum transverse momentum ($p_{Tmin}$) and different multiplicity classes following standard kinematical cuts used by the ALICE and the ATLAS experiments at the LHC for all three EPOS3 event samples. EPOS3 model shows a similar trend of FB multiplicity and momentum correlation strengths for both $pp$ \& $pPb$ systems, though the correlation strengths are found to be larger for $pPb$ system than $pp$ system. Moreover, $\delta\eta$-weighted average of FB correlation strengths as a function of different center-of-mass energies for $pp$ collisions delineates a tendency of saturation at very high energies., Comment: 10 Pages, 13 Figures, Accepted in Physical Review D

This paper presents a study on energy dependence of self-similar cascading rate of produced pions in nuclear collision in the entire accelerator energy 2.1A GeV-200A GeV using the results of F-moments methodology and Levy stable index in both pseudorapidity (η) space and azimuthal angle (ϕ) space. This analysis reveals a positive dependence of self-similar cascading rate on beam energy., Predstavljamo proučavanje energijske ovisnosti sličnih sljedova piona proizvedenih u nuklearnim sudarima u širokom području energije od 2.1 A GeV do 200A GeV 16O-AgBr sudari na 2.1A GeV i 60A GeV, Pb-Pb sudari na 158A GeV, te 32SAgBr sudari na 200A GeV. Primjenjujemo metodologiju F momenata i Levyjeve stabilne indekse za prostor pseudorapiditeta (η) i prostor azimutalnog kuta (φ). Analize pokazuju pozitivnu ovisnost sličnih sljedova piona o energiji sudara.

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.

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.

Measurement of charges ( 1 ≤ Z ≤ 3) of the projectile fragments produced in silicon-emulsion interaction at 14.5 AGeV was carried out with the help of lacunarity (L) method, using nuclear emulsion track detector. No fractionally-charged projectile fragment was found in this investigation. Only integrally-charged projectile fragments with Z=1,2 and 3 were detected., Mjerenje naboja (1 ≤ Z ≤ 3) dijelova čestica upadnog snopa proizvedenih u međudjelovanju jezgri silicija u emulziji na 14.5 AGeV načinjeno je primjenom metode isprekidanosti traga čestice, rabeći nukleografsku emulziju kao detektor. U ovom istraživanju nije nađena čestica s necijelim nabojem, već samo čestice s cjelobrojnim nabojima Z = 1, 2 i 3.

We investigated the multifractality of target fragments of 24Mg-AgBr interaction at low energy (4.5 AGeV) in emission angle phase space, using a new method as proposed by Takagi. The analysis involves the step of measuring the generalised dimension Dq, which in turn deducts the multifractal behaviour of target fragments. We also determine the multifractal specific heat., Istražujemo mnogofraktalnost izlaznih sporih čestica u sudarima 24Mg–AgBr na niskoj energiji (4.5 AGeV) u faznom prostoru kuta emisije, primjenom nove metode koju je predložio Takagi. U analizi se određuje poopćena dimenzija Dq iz koje se izvode mnogofraktalna svojstva izlaznih čestica. Također izvodimo mnogofraktalnu specifičnu toplinu.

This paper presents new results on the maximum gap (∆max) in the pseudorapidity distribution of charged particles in individual events in 24Mg-AgBr, 16O-AgBr and 32S-AgBr interaction in the energy range 4.5 − 200 AGeV. The location of the ∆max in an event and the experimental ∆max distribution at all energies has been studied in details. It has been observed that Gaussian distribution can describe the experimental data satisfactorily over the entire energy range., Predstavljamo nove ishode mjerenja maksimalnih procijepa (∆_max) u raspodjeli pseudorapiditeta nabijenih čestica u pojedinačnim sudarima 24Mg-AgBr, 16O-AgBr i 32S-AgBr na energijama 4.5−200 AGeV. Podrobno smo odredili položaje (∆_max) za pojedine sudare i proučili njihovu eksperimentalnu raspodjelu na tim energijama. Opažamo da Gaussova raspodjela može dobro opisati eksperimentalne podatke u cijelom području energija.

We present new data on target fragmentation in muon-nucleus interactions at (420 ± 45) GeV. A two-dimensional emission-angle -– azimuthal-angle plot of target fragments does not indicate preferential emission of target fragments. We also present an investigation on the two-particle short-range angular correlation among the target fragments in azimuthal-angle space. The experimental data have been compared with MC simulated events to extract dynamical correlation. The data exhibit strong two-particle correlation among target fragments in azimuthal space., Predstavljamo nove podatke o razbijanju meta u sudarima miona s jezgrama na (420 ± 45) GeV. Dvodimenzijski prikaz kut emisije – azimutalni kut ne pokazuje povezanost u emisiji krhotina mete. Predstavljamo također analize dvočestičnih kutnih korelacija kratkog dosega u azimutalnom smjeru. Usporedili smo podatke s Monte Carlo računima radi izvođenja dinamičkih korelacija. Podaci pokazuju jaku dvočestičnu korelaciju među krhotinama mete u azimutalnom smjeru.

Experimental data on compound multiplicity distribution produced in 24Mg-AgBr and 12C-AgBr interactions, both at 4.5A GeV, have been analysed in terms of scaled factorial moments. We have calculated the values of generalized dimension Dq for q = 2, 3, 4, 5, 6 and 7 with the help of intermittency exponent αq. From the knowledge of Dq, the multifractal specific heat is calculated for different multiplicity bin ranges. The parameter λq (λq = (αq + 1)/q) is calculated from αq to look for possible non-thermal phase transition. The analysis reveals no evidence of nonthermal phase transition. Instead, different specific heat in different multiplicity bins has been observed., Analizirali smo eksperimentalne podatke o raspodjelama složene višestrukosti u sudarima 24Mg-AgBr i 12C-AgBr, oba na 4.5A GeV, primjenom prilagodnih faktorijalnih momenata. Izračunali smo vrijednosti poopćene dimenzije Dq za q = 2, 3, 4, 5, 6 i 7 pomoću eksponenta prekidanja αq. Te vrijednosti Dq primijenili smo za izračunavanje višefraktalne specifične topline za niz pretinaca. Parametar λq (λq = (αq + 1)/q) smo izračunali na osnovi αq tražeći netermički fazni prijelaz. Analiza nije pokazala prisutnost netermičkog faznog prijelaza, ali smo našli različite specifične topline u pretincima.

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.

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.

This paper was published in Fizika B 6 (1997) page 37 with a typing error in the byline. The name of the fourth author was misspelled. Above is the corrected byline.

A measurement of charge of ultra-relativistic projectile fragments (1 ≤ Z ≤ 3) obtained in 16O-emulsion interaction at 60 A GeV/c has beee made. Li-projectile fragments were identified from the charge distribution of the projectile fragments. The transverse momentum distribution of the Li projectile fragments (Z = 3) was studied. The data were compared with Maxwell-Boltzmann distribution and they revealed the existence of a single temperature. The results are compared with other data on ultra-relativistic nuclear collisions., Načinili smo mjerenja naboja fragmenata sudara (1 # Z # 3) iz sudara 16O u nuklearnoj emulziji pri 60 GeV/c. Prepoznavanje litijevih jezgri među fragmentima zasniva se na određivanju naboja fragmenata. Proučavala se raspodjela poprečnih impulsa Li fragmenata. Podaci se uspoređuju s Maxwell-Boltzmannovom raspodjelom i oni ukazuju na jednu temperaturu u području sudara. Rezultati se uspoređuju s drugim podacima za ultrarelativističke sudare.

A comparative study has been made among three distributions - the negative binomial distribution (NBD), the generalised multiplicity distribution (GMD) and the distribution followed by the two mechanism model (TMM), in order to describe the multiplicity distribution of charged secondary particles produced in 200 200 A GeV 32S – AgBr interaction., Načinili smo usporedbu triju raspodjela: negativne binomijalne raspodjele, poopćene raspodjele mnogostrukosti i raspodjele prema modelu dvaju mehanizama, radi opisa raspodjela mnogostrukosti nabijenih čestica koje su bile proizvedene u sudarima iona 32S energije 200 A GeV u AgBr emulziji.