A. Smirnov

Status of the R&D towards electron cooling of RHIC

The physics interest in a luminosity upgrade of RHIC requires the development of a cooling-frontier facility. Detailed calculations were made of electron cooling of the stored RHIC beams. This has been followed by beam dynamics simulations to establish the feasibility of creating the necessary electron beam. The electron beam accelerator will be a superconducting Energy Recovery Linac (ERL). An intensive experimental R&D program engages the various elements of the accelerator, as described by 24 contributions to the 2007 PAC.

High-energy electron cooling based on realistic six dimensional distribution of electrons

The high-energy electron cooling system for RHIC-II is unique compared to standard coolers. It requires bunched electron beam. Electron bunches are produced by an Energy Recovery Linac (ERL), and cooling is planned without longitudinal magnetic field [1]. To address unique features of the RHIC cooler, a generalized treatment of cooling force was introduced in BETACOOL code [2] which allows us to calculate friction force for an arbitrary distribution of electrons. Simulations for RHIC cooler based on electron distribution from ERL are presented.

Status of the LEPTA Project

The Low Energy Particle Toroidal Accumulator (LEPTA) was commissioned in September 2004 at JINR. The facility is dedicated to studies of particle beam dynamics in a storage ring with longitudinal magnetic field focusing (so called “stellatron”), application of circulating electron beam to electron cooling of antiprotons and ions in adjoining storage ring, electron cooling of positrons, and positronium in‐flight generation. The last modes of the ring operation enables setting of numerous experiments with positronium in‐flight and generation of directed and “monoenergetic” flux of antihydrogen. The positronium (Ps) atoms appear in recombination of positrons with cooling electrons inside the cooling section of the ring. An assembling of the storage ring LEPTA was completed during year 2004.Peculiarity of the storage ring is focusing of circulating particles with longitudinal magnetic field which covers whole orbit. As result, the particle motion in the ring is coupled in transverse plane. First results of th...

Experimental approach to ultra-cold ion beam at S-LSR

At S-LSR, abrupt reduction of momentum spread of 7 MeV proton beam to ~2 times 10-6 at proton number of -2000 has been observed, which indicates phase transition to 1 dimensional ordered state. Attained proton temperatures after transition are 26 mueV and 1 meV for longitudinal and transverse directions, respectively, which compared with the corresponding values of 20 mueV and 34 meV for electron beam, indicates the magnetization of electron. Laser cooling of 24Mg+ has also been started and momentum spread of ~108 ions is reduced to 2 times 10-4, saturated with the momentum transfer from transverse degree of freedom by intra-beam scattering.

Application of ion beam cooling in the NICA accelerator complex. Experimental study of stochastic cooling at Nuclotron, JINR (Dubna)

The project of Nuclotron-based Ion Collider fAcility NICA/MPD (MultiPurpose Detector) is under development at JINR (Dubna) now. The general goals of the project are providing of colliding beams for experimental studies of both hot and dense strongly interacting baryonic matter and spin physics (in collisions of polarized protons and deuterons).