RuPAC2014 - Table of Session: TUCA (Particle dynamics in accelerators and storage rings, cooling methods)

Paper

Title

Page

Commissioning 2 MeV Cooler in COSY and Novosibirsk

14

V.B. Reva, M.I. Bryzgunov, A.V. Bubley, A.D. Goncharov, V.M. Panasyuk, V.V. Parkhomchuk
BINP SB RAS, Novosibirsk, Russia
J. Dietrich
HIM, Mainz, Germany
V. Kamerdzhiev
FZJ, Jülich, Germany
V.B. Reva
NSU, Novosibirsk, Russia

The 2 MeV electron cooling system for COSY-Julich was proposed to further boost the luminosity in presence of strong heating effects of high-density internal targets. The 2 MeV cooler is also well suited in the start up phase of the High Energy Storage Ring (HESR) at FAIR in Darmstadt. It can be used for beam cooling at injection energy and for testing new features of the high energy electron cooler for HESR. The COSY cooler is designed on the classic scheme of low energy coolers like cooler CSRm, CSRe, LEIR that was produced in BINP before. The electron beam is transported inside the longitudinal magnetic field along whole trajectory from an electron gun to a collector. The 2 MeV electron cooler was installed in the COSY ring in the spring 2013. Electron beam commissioning and first studies using proton and deuteron beams were carried out. Electron cooling of proton beam up to 1662 MeV kinetic energy was demonstrated. Maximum electron beam energy achieved so far amounted to 1.25 MeV. Voltage up to 1.4 MV was demonstrated. The cooler was operated with electron current up to 0.5 A.

Slides TUCA01 [2.066 MB]

TUCA02

On the Way to a Relativistic Electron Cooler

17

J. Dietrich
DELTA, Dortmund, Germany
K. Aulenbacher, M.W. Bruker, A. Hofmann
HIM, Mainz, Germany
M.I. Bryzgunov, V.V. Parkhomchuk, V.B. Reva
BINP SB RAS, Novosibirsk, Russia
V. Kamerdzhiev
FZJ, Jülich, Germany

A 4-8 MeV relativistic electron cooling system for the HESR storage ring, which is part of the future GSI facility FAIR, is needed to further boost the luminosity even with strong heating effects of high-density internal targets. In addition, the upgrade to 8 MeV of the relativistic electron cooler is essential for the future Electron Nucleon Collider (ENC at FAIR) project. Using the experience of the 2 MeV electron cooler at COSY, which has the highest energy of all coolers that were made based on the idea of magnetized cooling and transport of the electron beam up to now, a new concept for powering the solenoids at high voltage is proposed.

Slides TUCA02 [1.295 MB]

TUCA03

Beam Dynamics Optimization and RFQ Design

D.A. Ovsyannikov, V.V. Altsybeyev, A.D. Ovsiannikov
St. Petersburg State University, St. Petersburg, Russia
A.P. Durkin
MRTI RAS, Moscow, Russia
Y.A. Svistunov
Saint Petersburg State University, Saint Petersburg, Russia

Funding: This work was supported by St. Petersburg State University, project number 9.38.673.20
The problem of RFQ design is considered. Optimization approach to obtain desired output beam parameters is suggested. Acceleration of heavy ions (A/Z=20) is discussed. From start version up to the final one the BDO-RFQ and LIDOS RFQ associated codes are used.

TUCA04

Mechanism of Compression of Positron Clouds in the Surko Trap of the LEPTA Facility

20

M.K. Eseev, E.V. Ahmanova, A.G. Kobets, I.N. Meshkov, O. Orlov, A.A. Sidorin, S. Yakovenko
JINR, Dubna, Moscow Region, Russia
M.K. Eseev
NAFU, Arkhangelsk, Russia
A.G. Kobets
IERT, Kharkov, Ukraine

Results from experimental studies of plasma storage in the Surko trap at the LEPTA facility are presented. The number of stored particles is found to increase substantially when using the socalled "rotating wall" method, in which a transverse rotating electric field generated by a cylindrical segmented electrode cut into four pairs is applied to the positrons storage region. The conditions of transverse compression of the plasma bunch under the action of the rotating field and buffer gas are studied. The optimal storage parameters are determined for these experimental conditions. Mechanisms of the action of the rotating field and buffer gas on the process of positron clouds storage are presented.

Paper	Title	Page
TUCA01	Commissioning 2 MeV Cooler in COSY and Novosibirsk	14
	V.B. Reva, M.I. Bryzgunov, A.V. Bubley, A.D. Goncharov, V.M. Panasyuk, V.V. Parkhomchuk BINP SB RAS, Novosibirsk, Russia J. Dietrich HIM, Mainz, Germany V. Kamerdzhiev FZJ, Jülich, Germany V.B. Reva NSU, Novosibirsk, Russia
	The 2 MeV electron cooling system for COSY-Julich was proposed to further boost the luminosity in presence of strong heating effects of high-density internal targets. The 2 MeV cooler is also well suited in the start up phase of the High Energy Storage Ring (HESR) at FAIR in Darmstadt. It can be used for beam cooling at injection energy and for testing new features of the high energy electron cooler for HESR. The COSY cooler is designed on the classic scheme of low energy coolers like cooler CSRm, CSRe, LEIR that was produced in BINP before. The electron beam is transported inside the longitudinal magnetic field along whole trajectory from an electron gun to a collector. The 2 MeV electron cooler was installed in the COSY ring in the spring 2013. Electron beam commissioning and first studies using proton and deuteron beams were carried out. Electron cooling of proton beam up to 1662 MeV kinetic energy was demonstrated. Maximum electron beam energy achieved so far amounted to 1.25 MeV. Voltage up to 1.4 MV was demonstrated. The cooler was operated with electron current up to 0.5 A.
	Slides TUCA01 [2.066 MB]

TUCA02	On the Way to a Relativistic Electron Cooler	17
	J. Dietrich DELTA, Dortmund, Germany K. Aulenbacher, M.W. Bruker, A. Hofmann HIM, Mainz, Germany M.I. Bryzgunov, V.V. Parkhomchuk, V.B. Reva BINP SB RAS, Novosibirsk, Russia V. Kamerdzhiev FZJ, Jülich, Germany
	A 4-8 MeV relativistic electron cooling system for the HESR storage ring, which is part of the future GSI facility FAIR, is needed to further boost the luminosity even with strong heating effects of high-density internal targets. In addition, the upgrade to 8 MeV of the relativistic electron cooler is essential for the future Electron Nucleon Collider (ENC at FAIR) project. Using the experience of the 2 MeV electron cooler at COSY, which has the highest energy of all coolers that were made based on the idea of magnetized cooling and transport of the electron beam up to now, a new concept for powering the solenoids at high voltage is proposed.
	Slides TUCA02 [1.295 MB]

TUCA03	Beam Dynamics Optimization and RFQ Design
	D.A. Ovsyannikov, V.V. Altsybeyev, A.D. Ovsiannikov St. Petersburg State University, St. Petersburg, Russia A.P. Durkin MRTI RAS, Moscow, Russia Y.A. Svistunov Saint Petersburg State University, Saint Petersburg, Russia
	Funding: This work was supported by St. Petersburg State University, project number 9.38.673.20 The problem of RFQ design is considered. Optimization approach to obtain desired output beam parameters is suggested. Acceleration of heavy ions (A/Z=20) is discussed. From start version up to the final one the BDO-RFQ and LIDOS RFQ associated codes are used.

TUCA04	Mechanism of Compression of Positron Clouds in the Surko Trap of the LEPTA Facility	20
	M.K. Eseev, E.V. Ahmanova, A.G. Kobets, I.N. Meshkov, O. Orlov, A.A. Sidorin, S. Yakovenko JINR, Dubna, Moscow Region, Russia M.K. Eseev NAFU, Arkhangelsk, Russia A.G. Kobets IERT, Kharkov, Ukraine
	Results from experimental studies of plasma storage in the Surko trap at the LEPTA facility are presented. The number of stored particles is found to increase substantially when using the socalled "rotating wall" method, in which a transverse rotating electric field generated by a cylindrical segmented electrode cut into four pairs is applied to the positrons storage region. The conditions of transverse compression of the plasma bunch under the action of the rotating field and buffer gas are studied. The optimal storage parameters are determined for these experimental conditions. Mechanisms of the action of the rotating field and buffer gas on the process of positron clouds storage are presented.