ОбЪВАИНВННЫИ. АУ б На. El ИССJ18АОВ8НИИ. A.M.Baldin, L.A.Didenko, V.G.Grishin, A.A.Kuznetsov, z. V.Metreveli

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1 ОбЪВАИНВННЫИ ИНСТИТУТ RАВРНЫХ ИССJ8АОВ8НИИ АУ б На El A.M.Baldin, L.A.Didenko, V.G.Grishin, A.A.Kuznetsov, z. V.Metreveli HADRON JETS IN CUMULATIVE PROCESSES FOR п-с INTERACTIONS - А Т Р = 40 Ge V /с Subrnitted to the XXII International Conference on High Energy Physics (Leipzig, 984) *rер, Tbilisi State University, USSR 9.84

2 . INTRODUCTION The analysis of multiple hadron production in different processes, such as е+е- annihilation, deep-inelastic lepton-hadron collisions and soft hadron-hadron interactions, -ьаs shown that the production of hadron jets, which have а number of universal properties, is observed in these interactions / 0. Collective characteristics of the jets, "sphericity", "thrust" and others, the multiplicity of hadrons and their momentum distributions in the jets coincide for these processes at equal energies in the c.m.s. The observed similarity of the properties of hadron jets is probaьly due to the existence.of single mechanism of quark hadronization for soft and hard interactions. It is of interest to study the properties of hadron jets produced in hadron-nucleus collisions which can give information on the influence of nuclear matter on their formation and will allow one to estaьlish more general regularities of quark hadronization for different types of interactions. Cumulative processes are of principal interest / 4/, In this case quark-parton structure functions determined due to multiquark states in nuclei, are obtained from data on limiting nuclear fragmentation (Е > 3+4 GeV). Quark hadronization fro-m multiquark nuclear states is practically unstudied. Therefore it is particularly interesting to select jets in the region of nuclear fragmentatio and to compare them with the properties of hadron jets in е+е- and hadron-hadron interactions. This paper is devoted to the study of jet production in cumulative "-С interactions at 40 GeV/c. The results obtained are comparf'd with е+е- and "-Р data at Р = 40 GeV/c. Figure presents possiьle diagrams of the fragmentation production of hadron jets for "- р, е+е- and cumulative "-с interac tions, The analysis carried out in / 8 0 has shown that the production of two hadron jets in "-Р interactions, collimated towards an incident pion and in an opposite direction, can Ье mainly coцsidered as а result of the fragmentation of noninteracting u(d) quarks (forward hemisphere in the c.m.s.) and uu(ud) diquarks (backward hemisphere in the c.m.s.) from primary particles. Similarly, the production of secondary particle jets in the c.m.s. of "-с interactions can Ье presented as а result of the fragmentation of noninteracting ii(d) quarks from incident "- -rneson in the forward hemisphere and -t,--. - tl'т}'т i U!litНWX,,,:oюsd

3 rre nnr jttt/ - meson ('J) <>Н JUU!.-' nucteon (q.) s'f : д -----/6-;.--- ". 2 EXPERIМENT -Гр \ С'"С cumulative as а result of quark fragmentation from multiquark states of carbon nucleus in the backward hemisphere (region of targetnucleus fragmentation)., In this paper we study the fragmentation of quarks and diquarks into charged pions, neutral strange К 0 -mesons and Л - hyperons and collective characteristics of jets. Fig.. Schemes of rr р, cumulative "-с and е+е- interac - tions. Experimental data have been obtained using the 2m propane bubьle chamber exposed to а beam of 40 GeV /с "- -mesons at the Serpukhov accelerator. The work was done on statistics of 6480 rr -с interac tions * in which charged pions and protons were measured (the latter were identified over а momentum range of ' 200_$ Plab S 800 MeV/c), 550 K 0 -mesons (К 0 "+"] and 294Л - hyperons (Л prr-) were also usd in the a'halysis. 688 inelastic "-р interactions with '753 К 0 -mesons and 345 Л -hyperons 8 were used to compare wth the "-с data. The method of selection of "-р and "-с interactions, the identification of neutral strange particles and а further processing of the events are described in detail in papers /lб. 2О/. Multinucleon "-с interactions with the total charge of secondary particles Q"' N+- N_ = +, +2, +3, +4, where N+ and N_ are the numbers of secondary positive and negative particles per interaction, were selected for the analysis. In this case the protons having Р ь s 300 MeV /с were excluded as in this region the fraction oi spectator protons from th target-nucleus is large. For each group of mul tinucleon rr -с interactions with charge Q the analysis was performed in the c.m.s. of incident "- -meson and the corresponding number of nucleons (v ) involved in the interaction. In the events with Q = + the:e were two interacting protons, with Q = +2 three protons and 2 *Pion interactions with quasi-free nucleons were excluded. ', Туре of interaction Eventв Vli th cumulative jets j30.0 Eventв with cumulative jetв у..5 Statistics of events Average Energy Number of Q number events of inter- Ec.m.s. with given acting (Gs ') Q and nucleons nl Multinucleon interactionв all all all ТаЬlе Praction of events in % with ven Q from all / '"С interactions б so on. As neutrons also participate in these collisions, their number was estimated Ьу the momentum conservation law for the events with given Q in the collision c.m.s. 2. The energy of collision is defined Ьу the formula Ec,m.s.=' VS = "J2v 0 mnerr () with mn the nucleon mass and Е" the energy of incident pion. Such an approach makes it possiьle to observe the change of the properties of hadron jets, produced on nuclei, with increasing the number of' nucleons involved in the interaction what is somewhat similar to an investigation of the properties of hadron jets versus the atomic number of target-nucleus. ТаЬlе presents the number of events selected with charge Q = +, +2, +3, +4 and their fraction (in %) of the total cross section of "-с interactions. The cumulative events were selected using variaьle = Е- р =, where Е and Р are the energy and longi tudinal mome!um of secondary particles in the lab.system. According to the estaьlished selection criteria/ 22/ an event was assumed to Ье cumulative if а "±-meson with or а proton with 2. 3

4 was registrated in it. However, the hadronization of quarks from multiquark nuclear states can occur so that none of the particles has the value of outside the kinemaical limit of pion-nucleon collision whereas the sum of all in а jet, produced in quark hadronization, is larger than. (2) = I. >,. i As is shown/2, the events with cumulative particles incompletely reflect all cumulative processes and their configuration in momentum space. Thus, cumulative interactions were selected according to the condition (2): the events were selected in which the value of for а group (jet) of particles, moving backward in the c.m.s.(тr-vn),. was larger than.а group.of particles satisfying the condition (2) was assumed to Ье а cumulative jet. ТаЬlе presents the number of cumulative events thus selected and their fraction of all "-с interactions. The fraction of cumula ti ve j ets wi th К n -mesons and Л -hyperons was respectively -8% and 0% of all cumulative jets. 3. JET STRUCTURE The study of jet particle production in тr -с interactions has been performed using the standard variaьles: sphericity S and thrust Т. Sphericity S is defined as follows: S=!min(I.P 2 /I.\P*\ 2 ) (3) 2 i l.i with Р; the momenta of secondary particles in the collision c.m.s. and Pl.i the transverse moclenta of particle relative to some axi s : The ахз.s, for whз.ch Pl. has а mз.nз.mum value, з.s assumed to Ье а jet axis. Thrust Т is found according to the formula: T=max(I.\P;\ /I.\P.*\). (4).. Here Р is tbe projection of the momenta of secondary particles on some direction. The jet axis is defined as an axis which maximizes the sum I \Р \. These variaьles are described in detail in paper/28. It should Ье noted that variaьles S and determine the jet cone opening angle. Figure 2 shows the dependence of average values of sphericity <S> on collision energy Е for е+е- annihilation An average value of S c.mfr "-Р interactions at Ec.m.s. = 8. 7 GeV is also shown Ьу an arrow. In the same figure are presented average values of < S> versus Ес.m.в. for the j ets 4 ' il Fig.2. Average values of sphericity <S> for different types of interactions with n+?. 4 versus energy in the c.m.s. of colliding particles: V, а for е+е- annihilations; 8 - for cumulative tт-с interactions with >.0; i - for noncumulative тr -с collisions; а) for jets of secondary particles with х?. 0.05; Ь) for jets of secondary particles with х : (6)',,_"Gt\lo!: ft-ofi J._ Ц) I)AICI. Н f- :: : ::: l f- t t f ";il ";# f- Лl * t t +' + + 'J t' Q< '! s ю s ю е т of secondary particles collimated towards а primary pion and in an opposit direction in the cumulative ( >.О) and noncumulative ( <.0) events. The particles, having Jx J 2\Р \ = > refer to the jets. For comparison with the Е - е+е- c;fa'fa the j ets were selected in which the multiplici ty of charged particles, n± was 4. As seen from the figure, the value of <S> for both jets in cumulative тr-с interactions agrees with the е+е- data at equal energies in the c.m.s. For the noncumulative events one can see а disagreement with similar data on е+е- interactions for the hadron jets produced in the fragmentation region of target-nucleus. An analogous picture is observed when comparing the values of variaьle Т. In order to rule out а possiьle influence of such nuclcar effects as Fermi-motion and pion absorption in the nucleus which can lead to the production of particles and grops of particles with the value of 0 outside the kinematical limit of pion-nucleon collision, we have selected jets with?..5. In ТаЬlе are presented the number of events satisfying this condition and their fraction of all "-С interactions with n± 4. For the cumulative jets thus selected the dependence of average values of <8> on energy Е с.m.в. does not differ from that presented in fig ШLTIPLICITY OF SECONDARY PARTICLES. Hultiplicity of Charged Particles It is known that in various types of hadron-hadron interactions and in е+е- annihilation the multiplicity of charged particles is different: e.g., in рр collisions the average va- Е. s f""'l 5

5 '' л J' т--.--т-тт----т--т-- ю v 5 AOONE SPEAR МARtC. DASP.to PWTO TASSO JADE l'oanty-:t /.,;/,."" "' ; -' / /.-"". / Fig. 3. Aver_age multiplicity of charged particles, <n+>, versus energy in the c.m.s. for e+eand cumulative "-С interactions (Е). Solid curve - QCD prediction for е+е- annihilation. Туре of interaction Multiplicities of К n -mesons and А -hyperons in "-р and cumulative "-с interactions rr"p "-с, Q=+,+2 <v > = 3.3 n ТаЫе 2 6. o,l-l23&5uuiol-5-ioio Vs (GeV) ues of <n+> are smaer than in е+е- annihiation at the same energies in the c.m.s. (fig.з), and in "-Р and к-р interactions the vaues of <n+> coincide with the е+е- data at y's ::; 2 GeV 8 5 It is of i"nterest to compare the mutiplicity <n+> in е+- annihilation and in cumuative processes. -Figure 3 depicts the average mutipicity of charged partices versus y's in е+е- and cumulative "-с colisions. It is seen that in cumulative processes the vaue of <n+> increases with increasing Е 0 m, 8 and, within exerimentaf errors, it coincides with the values of <n+> for е е- annihiation at equa Ec.m.s.' However, the anaysis has shown that this increase of <n+> in cumulative processes is greaty due to increasing the number of protons in the fina state/2. 2. Mutipicities of Neutra Strange Partices ТаЬlе 2 shows the average mutipicities of Kn -mesons and А -hyperons in "-р and cumuative "-с interactions with charge Q = +, +2. As is seen from the taьle, the mutipicities of Kn -mesons and А -hyperons in cumuative interactions are larger than in pion-proton colisions. Nevertheess in "-с events the mutipicity of neutra kaons increases proportionally to the average mutipicity of rr 0 -mesons, <n>, in these events* so that within the experimenta errors,"the <nкn> ' f h с rato s sm ar or t ese nteractons. onsequent у, <n > in cumutive processes no additiona sources of strange meson production are observed as compared to neutra pions. In comparison with the mutiplicity of А -hyperons in pionnuceon collisions, the mutiplicity of А -hyperons in cumu- ative events increases approximatey in proportion to the number of nucleons invoved in the interaction. It is produced <ny>. supposed that y-quanta in the events are mainly from the decays of rr 0 -mesons, therefore <n> = Туре of partices <nк,а > <nк,а > <n"o> <nк,а> <vn > кn А кn. А h. h. h. < n А 5... Wt n t е expermenta errors, t е rato s sm ar for "-р and "-с interactions. <vn> 5. CНARACTERISTICS OF CНARGED PARTICLES IN JETS Besides the anaysis of the coective characteristics of the jets, sphericity and thrust, it is interesting to compare one-partice momentum distributions of secondary particles in the jets for cumuative "-с and е+е- interactions. In fig.4 is shown the transverse momentum squared distribution of а secondary particles in cumulative interactions with Q = + reative to the jet axis. The Р{ di.stributions of partices are simiar, within the experimenta errors, for the jets produced in the forward and backward hemisphere in the c.m.s. of (rr-vn) collisions. So figure 4 presents the sununed distribution for both hemispheres. The transverse squared distribution of charged partices relative to the jet axis in е+е- annihilation for approximatey close energies (y's: = = 3+7 GeV) is given in the same figure for comparison. As seen, these distributions are similar for both types of the interactions considered. 2Р Figure 5 illustrates the х = Е distributions of sec.m.s. condary partices in the forward and backward hemispheres in the c.m.s. of "-с interactions with Q= +, where Р is the longitudinal momentum of particles reative to the jet axis. The data are come!red with а similar distribution for е+ е- ennihilation at y's = 7.4 Gev 28 The distribution is normalized so tht the area under it in the range lx > 0. is the same as in rr С events. - 7

6 ? ml- - 'f l\ - -j,f 4';_, ч + 0, - t t t t - t- 0,0 fi 0,5,5 20 /f(wv/c)' Fig.4. Transverse momentum squared distribution of charged particles relative to the jet axis in cumulative "-С collisions at JS = 5. 3 GeV (8) and in е+ е- annihilation at vs = 3+ 7 GeV. «-.kl ).{ =. АА 6 ' ; t./ ttt+ t o,d Ц5 \0 \() -!,5 ж, Fig.5. х distribution of charged particles relative to the jet axis in cumulative rт-с interactions atvs: = 5.3 GeV and in е+е- annihilation at vsi = 7.4 GeV; а) distribution of particles in jets flying in the c.m.s.; Ь) distribution of particles in jets flying backward in the c.m.s. From the figure one can see that in cumulative rт-с collisions the distribution of particles in the jets, collimated towards an incident тг -meson, is in agreement with а similar distribution in е+е- interactions. For particles, produced in the fragmentation nuclear region in these events (both for pions and for protons),the х distribution relative to the jet axis differs from а similar distribution of charged particles in е+е- annihilation. This difference can Ье due to variations of initial states of interacting objects which leads to various compositions of secondary particles in the f inal state and to distributions in their phase space distribufions (in cumulative rт-с interactions with Q = + the average numьer of nucleons, <vn >, is 3.3 whereas in е+ е- annihilations at ys = 7.4 GeV the mean mul tiplicity of рр" pairs per event <npp > is <О. ). Therefore it would Ье more correct to compare identical systems of secondary particles in the final state (in this case meson ones) in their rest frame. With this aim the events with two i dentified protons were sel ected from cumulative rт- С interactions wit h Q = +. The protons were excluded from the analysis; the energy of the remaining ineson system, <М >, was 0 GeV The value of < М 0 > was decreased Ьу 6% if the fraction of neutrons i n the final state was accounted for Е"Т---.--т !="" * ++ r --lz \ j 0, Е- Q0 LL--' :. 0,5,0 s 2Р 5 -м. Fig. 7. у distribution of pions for cumulative "-С interactions at <М 0 > = 0 GeV and е+ е- annihilation atjs= 3 GeV J and 7.4 GeV. Fig. б. х distribution of pions in cumulative rт-с collisions for < м 0 > = 0 -GeV and in е+ е- annihilation for ys = 7. 4 GeV. ц+.\,,.. -. ) \,, :z, \ 'tl't! \ li 0,0:: ГС, <М.>=ЮGеv,. } er I[S Gev --- (S?.4Gev \j 0,00 r.! -2 'f". -'t. s The х: = and у distributions of charged pions calculated in the est frame of mesons (М 0 ), were analyzed. In this case ps is the total momentum of pions in their rest frame м 0 and у the rapidity determined relative to the jet axis in the same system (the jet axis was reconstructed Ьу variaьle Т). In such an approach the production of pion jets in the fragmentation region of target-nucleus can Ье interpreted as а result of the fragmentation of quarks from multiquark states of carbon nucleus. Figures б and 7 compare the dn and dn distributions dxs dy в of charged pions, produced in thernuclear fragmentation region for cumu.lative rт-с events at <М > = 0 GeV, with the xr and у distributions of pions in е+е- annihilation for approximately equal energies ys. As seen from the figures, these distributions of pions are similar for both types of interaction. 9

7 \ б. QUARК AND DIQUARК FRAGМENTATION INTO STRANGE PARTICLES,. Fragшentation Functions Comparing the processes of quark and diquark fragmentation into neutral К n -mesons and Л-hyperons for various types of interaction, we use the scaling function in terms of + -. fj dx'- whch the е е data are analyzed. Here хе"' 2E*/v'S; fj Р*/Е*; Р* and Е* are the moщentum and energy of the considered hadron in the coll ision c.m. s. According to quark-parton model predictions, for quark fragmentation this function depends only on variaьle хе: annihilation, we analyze the function Jl J![_ fj dxe 2. Fragmentation of 'U(d) Quarks into Strange Particles! -.F (хе). r (5) fj dxe q As taking into account factor S i s i mportant only for e+eas i n paper 0, Figures 8 and 9 present the.!. function.versus хе n fj ' dxe for neutr;й К -mesons and Л- nyperons produced in the cumul ative processes in the forward hemisphere in the c.m.s. of rr-v collisions. Similar distributions for neutral strange paricles in rr-p and е+е- interactions a r e given in the same figures/8,82 From the figures one can see that, within the expetimental errors, the dependence of the function on хе is similar for Kn-mesons and Л -hyperons i n cumulative (б) 7i dxe The va l ues of parameter В.and the range of approximation i n rr- p, cumul ative rr- С and е+е - colli s i ons a r e shown i n Т аьlе 3. From the Т аьl е it is seen that, wi t hin the experimental errors, А ехр(-вхе) the s lope s of the!_j![_ distributi ons determi ned Ьу rr-c, rr"}l and е +е- interactions. The! 2!! distributions for n. fj dxe К and Л -particles can Ье approximated Ьу t he exponentia dependence parameter В coincide fof К 2-Х me s on s and Л -hype r ons, producted in qua rk fragmentation (forward h emi phe r e), in cumulative rr-c rr-p and е+е- collisions. 0 "' е.r ttrr с. r. е!i""c'i"'46,3gev Тр 8,? GeV. e'f:l 0,2 0) 0,6 х ZE'I;r Fig.9..!. k distribution fj dxe for Л-hyperons in the frward hemisphere in the c.m.s. for cumulative rr-c, rr-p and e+ecollisions.. Normalization is the same. ' Fig.8. :хие distribution for кn-mesons in the forward hemisphere in the c.m.s. for cumulative rr- С, rr-p and е+ е- interactions. The distriьutions of К n - mesons in rr р and е е are normalized to the a're under their :: distribution in cumulative Е. \ J \ rr-c interactions. itt? "r.rr jo, - -t= O,it 'бцs 0.2 0, ' Tl).e average multiplicities of Kn -mesons and Л-hyperons, produ.ced in quark fr.agmentation in rr-p and cumulative rr-c interactions, are also similar: <nk>'-c = !_0.04; <nк>rr-p <nл>rr-c.б+.з; <nл> - - rr Р О.Об for 0.2 хе 0.5;.б+О.О0 for 0.3 $ х Е$ 06. These values of <nк.> and <nл> are in approximate agreement with the average multiplicity of кn -mesons and Л-hyperons produced in е+е- collisions due to strange sea quarks/88,4/ in the same х Е range. Using the data obtained, we have made an attempt to evaluate а relative pickup probability of strange s(s) quarks from the sea in comparison with u(ii) and d(d) quarks. This pro <n > bability can Ье determined Ьу Л 8 =.:::.::L. The value of Л 8 for <nrr>

8 м ()., CS Е-< 2 j:q () () CS '"' р. () ;::!. CS :> :: 't"i t ф 'R ь :: а! Р. Р. а! l! :: 't"i 't:! ш а а!.t Q Q а! j:q ::.-i t а! s ф ь g: 3 l! :: 'f"io). 't:!s. a!q О) ф. Q О) 't"i :: Р. ф t ф t Cll. Р. >. >. E-i "' "' lo., + с }-/IIJ N + cn О) ::. ;j Q t:.\j ::.: ь.() + cn I!J + Q О). :: :> () О) ф s N \.'- "".n r:--. N.().() U.l -ql + О) ::.-i Cll ;j Р. Q o;t. \J < : *' "'., (.\') 4 + О) Q!=:: > () ф Р. >..с:: o;t <==.()., IJl с;,.,.,.() -ql "'' \!) 'К + О) Q :: > ф ф Р. >.0 с:: lf!. =,_" l-< с О). Ф.-i Q ф а!+ Р. Q) < cumulative "-с interactions turned out to Ье what, within the experimental errors, agrees with that of Лв obtained for "-р tation а relative pickup probability of diquarks from the sea and е+ е- collisions For quark fragmen determined Ьу the relation Л = <nд> was The same qq <nк> - value of Л qq was obtained in "- interactions ( ) 0 and е+ е- annihilation (-0.08) /З - 3. Diquark Fragmentation into Strange Particles As is shown in the previous paragraph, in order to compare correctly the properties of hadron jets in various types of interactions, it is necessary to select identical systems of secondary part\cles in the final state. This is the reason why for comparison of the properties of К n -mesons and Л -hyperons, produced in the target-nucleus fragmentation region in cumulative processes, with the "-Р and е+ е- data, we have selected а system of secondary particles consisting of mesons and а baryon. Then the production of Л-hyperons and K 0 -mesons in the backward hemisphere in the rest frame of the selected subsystem can Ье considered as а result of the fragmentation of uu, ud or dd diquarks from multiquark states of carbon nucleus and other baryons as spectators. Cumulative -с collisions with Q = + and one identified proton, with Q = +2 and two protons were selected for this comparison. These.protons were excluded from the analysis. The energy of the remaining subsystem of secondary particles <M 0 >,was 2.3 GeV. Figures 0 and ll show the. dus function versus х n Е for К -mesons and Л -hyperons produced in the target-nucleus fragmentation region for cumulative "-с interactions with Q = +, +2. Here х = Ев and Е в is the energy of particles in the rest frame of sbsystem м 0 In the figures are also presented the JL J![_ distributions for neutral strange par- dxe ticles from е+е- and "-Р collisions in the b.ackward hemisphere n. the c.m.s. As s. seen f rom t h е f" gures, t h е J3 du d" Stributions for кn -mesons and Л-hyperons. agree_, Е within the experimental errors, in the considered х range for these different processes. ТаЬlе 3 displays the slopes В of the distribution for neutral strange particles produd f3 в n th&backward hemisphere in the rest frame of subsystem М 0 The slopes can Ье obtained Ьу approximating these distributions 3 t "'- "

9 0 Ъw -/.а.,0 *t т 9tФ t t f tt :п с, <м.> s f2.'gev :n-p.-a А ee-, '/S- 4 г-т-.--r-. 0,2 0,4 це 0,8 х: 2Е/'м. Fig.to. JL distribution. fj dx for K 0.-mesons in the backward hemisphere in the rest frame of suьsystem М for cumulative "-с interactions. The comparison is made with the 7-р and е.+е- data in the c.m.s..а Е.-jD., +-, щ ttt? 0, '=--'---+:--'----+=---'--:-'---:! 0,2 0,4 Fig :;в distribution for Л-hyperos in the backward in the rest frame of suьsysten М for cumulative "-С interactions. The comparison is made with' the "-Р + - and е е data in the c.m.s. Ьу dependence (б). From the ТаЬlе it is seen that the values of parameter В for К 0 - and Л-particles in cumulative events are consistent, within the errors, with the data. The value of slope В is also similar for К 0 -mesons from cumulative events and е+ е-.annihilation. As for Л -hype"rons produced from diquark fragmentation in "-Р and cumulatice -С interactions, the slope В is smaller than in е+е- annihilation. The results obtained mean that diquark fragmentation into neutral kaons and Л-hyperons fro multiquark states in light nuclei occurs in the same manner as diquark fragmentation into the same particles for soft hadron interactions. 7. МAIN CONCLUSIONS Based on the analysis performed, the following main conclusions can Ье drawn:. In cumulative "-с interactions with the number of inter- acting nucleons v 0 5 the production of hadron jets is ohserved that are collimated towards an incident pion and in an opposite direction in the c.m.s. of 7-Vn collisions. The value of spheri city for both jets coincide with the data for е+е- and hadron hadron i ntera tions at equal energies in the c.m.s In -С interactions the longitudinal and transverse momentum distributions of pions for the cumulative jets and also for the jets collimated towards an incident pion agree with similar distributions of "±-mesons in е +е- annihilation. 3. Within the experimental errors, the average multiplicity of charged particles in cumulative -С interactions is in agreement with the multiplicity <n+> in е + е- annihilation for equal energies in the c.m.s. - А 4. The quark fragmentaton fnctios :F ( )(хе) fo_: K 0 -mesns and Л -hyperons in cumulatve rr С, е е and soft rr Р collsions have а similar х Е -dependence. The mean mul tiplici ties of К 0 -mesons and, A-hyperons produced in quark fragmentation due to the pickup of strange quarks from the sea, coincide, within the errors, in these interactions. 5. In cumulative "-. с interactions the diquark fragmentation functions. FA)(xE) for K 0 -mesons and A-hyperons from multiquark states of target-nucleus are consistent with similar "-р data. Within the errors, the fragmentation functions of diguarks.f (хе) in cumuative "-с interactions and of quarks. F(x.E) in е+е- annihilation for К 0 -mesons are similar in the range ХЕ ::;0.4. The results obtained indicate that the quark and diquark fragmentation into "±-mesons and strange particles is universal in cumulative interactions on light nuclei, soft hadron collisions and e+e- annihilation. The fragmentation of mul t iquark states on light nuclei is s imilar to that of quarks and diquarks in soft and hard collisions of particles. REFERENCES. Basile р.3; 2. Basile р.44; р.53. М. et al. Phys.Lett., 980, 92В, р.367; 95В, 98, 99В, р.247. М. et al. Nuovo Cim., 980, 58А, р.93; 98, 65А, 98, 65А, р.400; 982, 67А, р.244; 982, 67А, 3. Gottgens R. et al. Nucl.Phys., 98, Bl78, р Grishin V.G. et al. Yad.Fiz., 983, 37, р.95; JINR, Pl-8-542, Dubna, Barth М. et al. Nucl.Phys., 98, Bl92, р.289. б. Breakstrone А. et al. CERN/EP 8-68 Rev., Geneva, July, Palmonary F. Grishin V.G. Grishin V.G. Grishin V.G. CERNEP/82-76, Geeva, November, 982. et al. JINR, Р-83-ЗО6, Dubna, 983. et al. JINR, Pl , Dubna, 983. et al. JINR, Pl-84-79, Dubna,

10 . Baldin А.М. ЕСНАУА, 977, 8, р Baldin А.М. Proc. of IV Int.Seminar on High Energy Phys. ProЬl., JINR, Dl , Dubna, Stavinsky V.S. ЕСНАУА, 979, 0, р Baldin /(.. JINR, El , Dubna, BBCDSS TTU-BW. Collaboration. Phys.Lett., 972, 39В, р Abdurakhimov A.U. et al. JINR, Pl-6326, Dubna, 972; Yad.Fiz., 973, 8, р Angelov N. et al. JINR, Pl-0324, Dubna, 976; Yad.Fiz., 977, 25, p.ioi3. 8. Abdurakhimov A.U. et al. JINR, Pl-7267, Dubna, 973; Yad. F i z., 973, 8, р Angelov N. et al. JINR, Pl-9648, Dubna, 976; Yad.Fiz., 977, 25, р.350; JINR, Pl-9209, Dubna, 975; Yad.Fiz., 976, 24, р Angelov N. et al. JINR, Pl-8-05, Dubna, 98; Yad.Fiz., 98 ' 34' р Baldin A.}f. et al. JINR, Pl , Dubna, Anoshin A.I. et al. Yad.Fiz., 982, 36, р Brandt S., Dahman H.D. Z.Phys., 979, Cl, р Berger С. et al. Phys.Lett., 979, 82В, р.449; 978, 78В, p.l76; 979, 8В, р.4 : 25. Brandelik R. et al. Phys.Lett., 979, 83В, р Barber D. et al. Phys.Rev.Lett., 979, 42, p.lll GUnter W. DESY 80/85, Sept., Hanson G.G. SLAC Pub-84, September, Drell S.D. et al. Phys.Rev., 969, 87, р.259; 970, Dl, p.l Wolf G. DESY 80/85, September, Oberlack Н. MPI-PAE/EXP, El, 0, September, Wolf G. DESY, 8-086, December, Bartell W. et al. Z.Physik С., 983, 20, p.l87. ' Балди А.Н. и др. Е-8-37 Струи адрв в кумулятивых прцессах в.-с-взаимдействиях при Р О ГэВ/с Изучается бразваие струй адрв в кумулятивых.-с-взаимдействиях при импульсе О ГэВ/с. Аализируются кллективые характеристики струй, мжествести втричых частиц, их имn,сtсые распределеия в труях. Иэуча0тся фукции фрагметации кваркв.f q ) (Е) и дикваркв.f Л (хе) из мультикварквых сстяий ядра углерда в еитральые страые частицы. Пnучеwе результаты сравива0тся с аалгичыми даыми для.-р- и е+е- -стлквеий. Пкаэа, чт все изучеые характеристики пив 8 струrх в кумулrтмвых rr- С -взаимдействиях и в ее- -аигиляции диаквы. Фукция фрагметации кваркв м дикваркв в ейтральые страые частицы в кумумтивwх.-с -стлквеиях и в.-р-взадействиях свnадаdт. Свnада0т также фукции фрагметации кваркв F: (хе) в страые частицы в кумумтмвых "-С -взаимдействиях и в е+е- -аигиляции. Рабта выnлеа в Лабратрии выских эергий ОИЯИ. ПpenPJUIT Оег JUICTJIТYT& JIДepwx исспедваий. Дуба 984 Badln А.Н. et al. Hadгon Jets ln Cumulatlve Pгocesses fг.-с lnteгactions at Р 40 GeV/c Е The pгoductlon of hadron jets ls studled ln c:umulat-lve.-с lnterac: tlons at 40 GeV/c. Collectlve characterlstlcs, multlpllclty and momentum dlstrlbutlons of secondary particls from the jets are analysed. The fragmentatlon functlons of quarks r:<a (хв) and diquarks.r,jt) (хв> from multlquark states for neutral strange particles are studled. ne obtained results are compared wlth slml-lar "-Р and е+е- data. lt ls shown that all plon characterlstlcs studied from the jets ln cumulatlve "-с lnteractlons and е.- ann lhllat lon are s lmllar. The quark and d i quark fragmentat lon functlons for neutral strange partlcles colnclde, wlthln the errors, ln c\atlve "-с and "-, coll islons. The quark fragmentation functions -F <хв> for strange particles are also slmllar ln cumulatlve.-с interactlons and е+в- annlhllation. The investigatlon has been performed at the Laboratory of Hlgh Energles, JINR. 6 Received Ьу PuЬlishing Department on Мау 4, 984. = Preprint of the Joint lnstitute for Nuclear Research. DuЬna 984