IPAC2013 - List of Authors (Nissen, E.W.)

Paper	Title	Page
MOPWO077	Design of the Proposed Low Energy Ion Collider Ring at Jefferson Lab	1058
	E.W. Nissen, F. Lin, V.S. Morozov, Y. Zhang JLAB, Newport News, Virginia, USA
	Funding: Supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC05-06OR23177 and DE-AC02-06CH11357. The polarized Medium energy Electron-Ion Collider (MEIC) envisioned at Jefferson Lab will cover a range of center-of-mass energies up to 65 GeV. The present MEIC design could also allow the accommodation of low energy electron-ion collisions (LEIC) for additional science reach. This paper presents the first design of the low energy ion collider ring which is converted from the large ion booster of MEIC. It can reach up to 25 GeV energy for protons and equivalent ion energies of the same magnetic rigidity. An interaction region and an electron cooler designed for MEIC are integrated into the low energy collider ring, in addition to other required new elements including crab cavities and ion spin rotators, for later reuse in MEIC itself. A pair of vertical chicanes which brings the low energy ion beams to the plane of the electron ring and back to the low energy ion ring are also part of the design.

MOPWO078	A Harmonic Kicker Scheme for the Circulator Cooler Ring in the Medium Energy Electron-ion Collider	1061
	E.W. Nissen, A. Hutton, A.J. Kimber JLAB, Newport News, Virginia, USA
	Funding: Supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC05-06OR23177 and DE-AC02-06CH11357. The current electron cooler design for the proposed Medium Energy Electron-Ion collider (MEIC) at Jefferson Lab utilizes a circulator ring for reuse of the cooling electron bunch up to 100 times to cool the ion beams. This cooler requires a fast kicker system for injecting and extracting individual bunches in the circulator ring. Such a kicker must work at a high repetition rate, up to 7.5 to 75 MHz depending on the number of turns in the recirculator ring. It also must have a very short rise and fall time (of order of 1 ns) such that it will kick an individual bunch without disturbing the others in the ring. Both requirements are orders of magnitude beyond the present state-of-the-art as well as the goals of other on-going kicker R&D programs such as that for the ILC damping rings. In this paper we report a scheme of creating this fast, high repetition rate kicker by combining RF waveforms at multiple frequencies to create a kicker waveform that will, for example, kick every eleventh bunch while leaving the other ten unperturbed. We also present a possible implementation of this scheme as well as discuss its limitations.

MOPWO083	LEIC - A Polarized Low Energy Electron-ion Collider at Jefferson Lab	1070
	Y. Zhang, Y.S. Derbenev, A. Hutton, G.A. Krafft, R. Li, F. Lin, V.S. Morozov, E.W. Nissen, R.A. Rimmer, H. Wang, S. Wang, B.C. Yunn, H. Zhang JLAB, Newport News, Virginia, USA M.K. Sullivan SLAC, Menlo Park, California, USA
	Funding: Supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC05-06OR23177 and DE-AC02-06CH11357. A polarized electron-ion collider is envisioned as the future nuclear science program at JLab beyond the 12 GeV CEBAF. Presently, a medium energy collider (MEIC) is set as an immediate goal with options for a future energy upgrade. A comprehensive design report for MEIC has been released recently. The MEIC facility could also accommodate electron and proton/ion collisions in a low CM energy range, covering proton energies from 10 to 25 GeV and ion energies with a similar magnetic rigidity, for additional science reach. In this paper, we present a conceptual design of this low energy collider, LEIC, showing its luminosity can reach above 10³³ cm^-2s⁻¹. The design specifies that the large booster of the MEIC is converted to a low energy ion collider ring with an interaction region and an electron cooler integrated into it. The design provides options for either sharing the detector with the MEIC or a dedicated low energy detector in a third collision point, with advantages of either a minimum cost or extra detection parallel to the MEIC operation, respectively. The LEIC could be positioned as the first and low cost phase of a multi-stage approach to realize the full MEIC.

Paper

Title

Page

Design of the Proposed Low Energy Ion Collider Ring at Jefferson Lab

1058

E.W. Nissen, F. Lin, V.S. Morozov, Y. Zhang
JLAB, Newport News, Virginia, USA

Funding: Supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC05-06OR23177 and DE-AC02-06CH11357.
The polarized Medium energy Electron-Ion Collider (MEIC) envisioned at Jefferson Lab will cover a range of center-of-mass energies up to 65 GeV. The present MEIC design could also allow the accommodation of low energy electron-ion collisions (LEIC) for additional science reach. This paper presents the first design of the low energy ion collider ring which is converted from the large ion booster of MEIC. It can reach up to 25 GeV energy for protons and equivalent ion energies of the same magnetic rigidity. An interaction region and an electron cooler designed for MEIC are integrated into the low energy collider ring, in addition to other required new elements including crab cavities and ion spin rotators, for later reuse in MEIC itself. A pair of vertical chicanes which brings the low energy ion beams to the plane of the electron ring and back to the low energy ion ring are also part of the design.

MOPWO078

A Harmonic Kicker Scheme for the Circulator Cooler Ring in the Medium Energy Electron-ion Collider

1061

E.W. Nissen, A. Hutton, A.J. Kimber
JLAB, Newport News, Virginia, USA

Funding: Supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC05-06OR23177 and DE-AC02-06CH11357.
The current electron cooler design for the proposed Medium Energy Electron-Ion collider (MEIC) at Jefferson Lab utilizes a circulator ring for reuse of the cooling electron bunch up to 100 times to cool the ion beams. This cooler requires a fast kicker system for injecting and extracting individual bunches in the circulator ring. Such a kicker must work at a high repetition rate, up to 7.5 to 75 MHz depending on the number of turns in the recirculator ring. It also must have a very short rise and fall time (of order of 1 ns) such that it will kick an individual bunch without disturbing the others in the ring. Both requirements are orders of magnitude beyond the present state-of-the-art as well as the goals of other on-going kicker R&D programs such as that for the ILC damping rings. In this paper we report a scheme of creating this fast, high repetition rate kicker by combining RF waveforms at multiple frequencies to create a kicker waveform that will, for example, kick every eleventh bunch while leaving the other ten unperturbed. We also present a possible implementation of this scheme as well as discuss its limitations.

MOPWO083

LEIC - A Polarized Low Energy Electron-ion Collider at Jefferson Lab

1070

Y. Zhang, Y.S. Derbenev, A. Hutton, G.A. Krafft, R. Li, F. Lin, V.S. Morozov, E.W. Nissen, R.A. Rimmer, H. Wang, S. Wang, B.C. Yunn, H. Zhang
JLAB, Newport News, Virginia, USA
M.K. Sullivan
SLAC, Menlo Park, California, USA

Funding: Supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC05-06OR23177 and DE-AC02-06CH11357.
A polarized electron-ion collider is envisioned as the future nuclear science program at JLab beyond the 12 GeV CEBAF. Presently, a medium energy collider (MEIC) is set as an immediate goal with options for a future energy upgrade. A comprehensive design report for MEIC has been released recently. The MEIC facility could also accommodate electron and proton/ion collisions in a low CM energy range, covering proton energies from 10 to 25 GeV and ion energies with a similar magnetic rigidity, for additional science reach. In this paper, we present a conceptual design of this low energy collider, LEIC, showing its luminosity can reach above 10³³ cm^-2s⁻¹. The design specifies that the large booster of the MEIC is converted to a low energy ion collider ring with an interaction region and an electron cooler integrated into it. The design provides options for either sharing the detector with the MEIC or a dedicated low energy detector in a third collision point, with advantages of either a minimum cost or extra detection parallel to the MEIC operation, respectively. The LEIC could be positioned as the first and low cost phase of a multi-stage approach to realize the full MEIC.