Selected Problems of Relativistic Nuclear Physics and Multiple

Selected Problems of Relativistic Nuclear Physics and Multiple Particle Production A. I. Malakhov Joint Institute for Nuclear Research, Dubna XXXII International Symposium on Multiparticle Dynamics, Alushta, 7 -13 September 2002

It is possible to obtain the record high energy particle beams by means of accelerating the heavy nuclei with large charges January 1, 1971

L. S. Schroeder et al. Phys. Rev. Lett. , v. 43, No. 24, 1979, p. 1787 e Dependence of T 0 parameter for pion at 180 o for p-Cu collisions on the energy of incident proton Tp. Pion crosssection parameterized by the form E·d /dp 3 = C·exp( -T/T 0), where T is the pion laboratory kinetic energy

Classification of Relativistic Nuclear Collisions on bik ~ 10 -2 classic nuclear physics 0. 1 bik < 1 intermediate domain bik >> 1 nuclei should be considered as quark-gluon systems

The experiments show the following dependence for crosssections of all nuclei from He up to U: (AI AII h 1 + …) = k·AIn ·AIIm(x)·exp(-x/<x>) b. I 1 > b. I II >> 1 0. 5 x 3. 3 (Cumulative effect: x > 1) m(x) = 2/3 + x m(x) = 1 (0. 5 x 1) (x > 1) <x> 0. 14 The dimension of the multi-quark system which produces cumulative particles The nuclear quark-parton structure function: G(x) ~ exp (-x/<x>)

The experiments in LHE (JINR): The limit fragmentation is realized at bik ≥ 5 The detailed investigation of cumulative particle production has been carried out on more than 20 nuclei The universal values ~ (1/AII) FII (b. II 1, x 1) practically don’t depend on properties of the nucleus I

Multiple Processes in Four-velocity Space

Processes with Very High Multiplicity The theory of these processes was developed at the Laboratory of Theoretical Physics of JINR (A. Sissakian and J. Manjavidze) in order to understand inelastic highenergy hadronic and nuclear interactions with the hadron multiplicity to be much higher than the average multiplicity

Пmin d. П/d. NI = 0; d. П/d. NII = 0 In the central rapidity region (y = 0) -Y AI (u 1 u. I) = (u 1 u. II) y y=0 +Y AII NI =NII = where and N = [1 + √ 1 + (Ф /Ф 2)]Ф, Ф= (1/m 0)[m. Tch. Y+ ](½ sh 2 Y) Ф= ( 2 - m 12)(4 m 0 2 sh 2 Y) Пmin = N ch. Y

Asymptotics s/(2 m. II) (u. II) = ch 2 Y П min= (m. T/2 m 0)[1+ √ 1+( 2 -m 12)/m. T 2 N 0

The analytical representation for П leads to the following conclusions: There is the limiting value of П at high energies The ratio of particle to antiparticle and nucleus to antinucleus production cross-section goes to the unit while energy rising The effective number of nucleons involved in the reaction decreases with increasing collision energy Probability of observation of antinuclei and fragments in the central rapidity region is small Strange particles yield increases with increasing collision energy

PREDICTIONS

Nuclotron intensity (particles per cycle) Beam available JINR Veksler & Baldin Laboratory of High Energies Dubna NUCLOTRON have to be (with booster) p 2. 5· 10 10 1013 d 3· 108 5· 1010 t 4· 105 1010 4 He 8· 108 2· 1012 7 Li 2· 109 5· 1012 12 C 6. 5· 108 2· 1012 24 Mg 1. 2· 108 5· 1011 40 Ar 104 1010 103 5· 108 84 Kr

Experiments with relativistic nuclei Nuclotron Experiments with polarized beams Applied investigations

Experiments with relativistic nuclei • Nucleon structure • Nuclear structure • Medium effects on particle production • Modification of nuclear matter • Hypernuclei and nuclei

Experiments with relativistic nuclei • Nucleon structure NIS project Polarized nucleon strangeness The planned results are: Ratio of and meson production cross sections near their thresholds in pp interaction and the comparison on the cross sections for pp and np interactions under similar kinematical conditions SUCH EXPERIMENT IS POSSIBLE IN THE FORESEEN FUTURE ONLY AT NUCLOTRON !

Experiments with relativistic nuclei • Nucleon structure STRELA project (d /dt)dp (pp)n = 2/3(d /dt)np pn Study of the spin-dependent component of the nucleon scattering amplitude in the charge-exchange process np pn in a deuteron beam extracted from the Nuclotron

Experiments with relativistic nuclei • Nuclear structure BECQUEREL project

Experiments with relativistic nuclei • Modification of nuclear matter FAZA project • Hot nuclei F L F • Termal mulifragmentation • Liquid-Fog Phase Transition Tc = (20± 2) Me. V E

Experiments with relativistic nuclei • Hypernuclei GIBS project SPHERE project • nuclei DELTA project

Experiments with polarized beams • Spin structure of the np forward scattering amplitude • Spin deuteron structure at short distances • Spin structure of the three nucleon systems

Experiments with polarized beams • Spin structure of the np forward scattering amplitude DELTA-SIGMA project is the total cross section for unpolarized particles and are the spin-dependent contributions is a unit vector in the direction of the beam momentum and are the beam (B) and target (T) polarizations T(np)

Experiments with polarized beams • Spin deuteron structure at short distances PIKASO project SCAN-2 project

Applied research • Radiobiology and space biomedicine • The impact of nuclear beams on the microelectronic components • The transmutation of radioactive waste • Accelerator driven energy production

Conclusions The Baldin and Veksler Laboratory of High Energies of JINR has obtained unique results in Relativistic Nuclear Physics The relevant programme of physics research will realize by international collaborations at the Nuclotron

1. A. I. Malakhov, Research Program for the Nuclotron, Physics of Atomic Nuclei, Vol. 65, No. 2, 2002, pp. 211 -219. 2. Selected Problems of Relativistic Nuclear Physics and Multiple Particle Production, Physics A. M. Baldin, A. I. Malakhov, A. N. Sissakian, of Particles and Nuclei, Vol. 32, Suppl. 1 (2001) pp. 4 -30. 3. V. I. Sharov et al. , Measurement of the np total cross section difference L at 1. 59, 1. 79 and 2. 20 Ge. V, Eur. Phys. J. C 13, 255 (2000). 4. S. Afanasiev et al. , Spin Effects at Fragmentation of Polarized Deuterons into Cumulative Pions, In Proceedings of the International Nuclear Physics Conference INPC 2001, Berkeley, California, 2001, Ed. By Eric Norman et al. Melville, New York, 2002, AIP Conference Proceedings, Vol. 610, p. 395. 5. S. P. Avdeev et al. Transition from thermal to rapid expansion in multifragmentation of gold induced by light relativistic projectiles, Physics Letters B 503 (2001) 256 -262. 6. V. P. Ladygin at al. , Measurment of the tensor analyzing powers in the dd 3 He n and dd 3 H p reactions at RIKEN, Part. And Nucl. Lett. 3[100]-2000 (2000) 74.