IPAC2016 - List of Authors (Ostojic, R.)

Paper	Title	Page
MOPOY009	ELENA: Installations and Preparations for Commissioning	860
	C. Carli, W. Bartmann, P. Belochitskii, H. Breuker, F. Butin, T. Eriksson, R. Ostojić, S. Pasinelli, G. Tranquille CERN, Geneva, Switzerland W. Oelert Johannes Gutenberg University Mainz, Institut für Physik, Mainz, Germany
	The Extra Low Energy Antiproton ring (ELENA) is a small 30 m circumference synchroton under construction at CERN to further decelerate antiprotons from the Antiproton Decelerator AD from 5.3 MeV to 100 keV. Controlled deceleration in a synchrotron equipped with an electron cooler to reduce emittances in all three planes will allow the existing AD experiments to increase substantially their antiproton capture efficiencies and render new experiments possible. Installation of the machine and lines needed for the commissioning of the ring are ongoing and commissioning is expected to start around mid-2016. The aim is to complete ELENA ring commissioning in November followed by the installation of new electrostatic transfer lines to existing experiments until autumn 2017. Status of ELENA installations and preparations for commissioning will be reported.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY009
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TUPMR046	Sources of Emittance Growth at the CERN PS Booster to PS Transfer	1352
	W. Bartmann, J.L. Abelleira, F. Burkart, B. Goddard, J. Jentzsch, R. Ostojić CERN, Geneva, Switzerland
	The CERN PS Booster (PSB) has four vertically stacked rings. After extraction from each ring, the bunches are recombined in two stages, comprising septum and kicker systems, such that the accumulated bunch train is injected through a single line into the PS. Bunches from the four rings go through a different number of vertical bends, which leads to differences in the betatron and dispersion functions due to edge focussing. The fast pulsed systems at PSB extraction, recombination and PS injection lead to systematic errors of delivery precision at the injection point. These error sources are quantified in terms of emittance growth and particle loss. Mitigations to reduce the overall emittance growth at the PSB to PS transfer within the LHC injectors upgrade are presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR046
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THPMB047	Beam Dynamics Studies of the ELENA Electrostatic Transfer Lines in the Presence of Magnetic Stray Fields	3351
	J. Jentzsch, W. Bartmann, M.A. Fraser, R. Ostojić, G. Tranquille CERN, Geneva, Switzerland D. Barna University of Tokyo, Tokyo, Japan
	The ELENA (Extra Low ENergy Antiproton) ring at CERN will further decelerate antiprotons produced at the AD (Antiproton Decelerator) facility from a kinetic energy of 5.3 MeV to 100 keV. The antiprotons will be distributed through a network of electrostatic transfer lines to several experiments, which will replace the existing magnetic transfer lines. The existing experiments and limited space in the AD hall forces the new transfer lines into close proximity to the high-field solenoids used by some experiments to trap the antiprotons. The stray fields from the experimental magnets are known to perturb beam delivery and are a concern for operation at the decreased beam rigidity provided by ELENA. A study was carried out to investigate the influence of stray magnetic fields on the beam, including different ramping periods and operational scenarios. The analytical model of the fields used for simulation will be discussed. Furthermore, trajectory correction algorithms using MADX optic model of the lines have been investigated. The results of these studies as well as specifications of acceptable stray field limits and field attenuation requirements will be presented.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB047
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Paper

Title

Page

ELENA: Installations and Preparations for Commissioning

860

C. Carli, W. Bartmann, P. Belochitskii, H. Breuker, F. Butin, T. Eriksson, R. Ostojić, S. Pasinelli, G. Tranquille
CERN, Geneva, Switzerland
W. Oelert
Johannes Gutenberg University Mainz, Institut für Physik, Mainz, Germany

The Extra Low Energy Antiproton ring (ELENA) is a small 30 m circumference synchroton under construction at CERN to further decelerate antiprotons from the Antiproton Decelerator AD from 5.3 MeV to 100 keV. Controlled deceleration in a synchrotron equipped with an electron cooler to reduce emittances in all three planes will allow the existing AD experiments to increase substantially their antiproton capture efficiencies and render new experiments possible. Installation of the machine and lines needed for the commissioning of the ring are ongoing and commissioning is expected to start around mid-2016. The aim is to complete ELENA ring commissioning in November followed by the installation of new electrostatic transfer lines to existing experiments until autumn 2017. Status of ELENA installations and preparations for commissioning will be reported.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-MOPOY009

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TUPMR046

Sources of Emittance Growth at the CERN PS Booster to PS Transfer

1352

W. Bartmann, J.L. Abelleira, F. Burkart, B. Goddard, J. Jentzsch, R. Ostojić
CERN, Geneva, Switzerland

The CERN PS Booster (PSB) has four vertically stacked rings. After extraction from each ring, the bunches are recombined in two stages, comprising septum and kicker systems, such that the accumulated bunch train is injected through a single line into the PS. Bunches from the four rings go through a different number of vertical bends, which leads to differences in the betatron and dispersion functions due to edge focussing. The fast pulsed systems at PSB extraction, recombination and PS injection lead to systematic errors of delivery precision at the injection point. These error sources are quantified in terms of emittance growth and particle loss. Mitigations to reduce the overall emittance growth at the PSB to PS transfer within the LHC injectors upgrade are presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-TUPMR046

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPMB047

Beam Dynamics Studies of the ELENA Electrostatic Transfer Lines in the Presence of Magnetic Stray Fields

3351

J. Jentzsch, W. Bartmann, M.A. Fraser, R. Ostojić, G. Tranquille
CERN, Geneva, Switzerland
D. Barna
University of Tokyo, Tokyo, Japan

The ELENA (Extra Low ENergy Antiproton) ring at CERN will further decelerate antiprotons produced at the AD (Antiproton Decelerator) facility from a kinetic energy of 5.3 MeV to 100 keV. The antiprotons will be distributed through a network of electrostatic transfer lines to several experiments, which will replace the existing magnetic transfer lines. The existing experiments and limited space in the AD hall forces the new transfer lines into close proximity to the high-field solenoids used by some experiments to trap the antiprotons. The stray fields from the experimental magnets are known to perturb beam delivery and are a concern for operation at the decreased beam rigidity provided by ELENA. A study was carried out to investigate the influence of stray magnetic fields on the beam, including different ramping periods and operational scenarios. The analytical model of the fields used for simulation will be discussed. Furthermore, trajectory correction algorithms using MADX optic model of the lines have been investigated. The results of these studies as well as specifications of acceptable stray field limits and field attenuation requirements will be presented.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-THPMB047

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