LINAC2014 - List of Keywords (lattice)

Paper	Title	Other Keywords	Page
MOPP003	A Compact Linac Design for an Accelerator Driven System	linac, cavity, cryomodule, focusing	52
	B. Mustapha, S.V. Kutsaev, J.A. Nolen, P.N. Ostroumov ANL, Argonne, USA
	Funding: This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357. A compact linac design has been developed for an Accelerator Driven System (ADS). The linac is under 150 meters in length and comprises a radio-frequency quadrupole (RFQ) and 20 superconducting modules. Three types of half-wave cavities and two types of elliptical cavities have been designed and optimized for high performance at frequencies of 162.5, 325 and 650 MHz. The lattice is being designed and optimized for operation with a peak power of 25 MW for a 25 mA – 1 GeV proton beam. The cavities RF design as well as the linac lattice will be presented along with end-to-end beam dynamics simulations for beam currents ranging from 0 to 25 mA.

MOPP039	Dynamics of Bunches Partially Chopped with the MEBT Chopper in the ESS Linac	linac, DTL, simulation, quadrupole	146
	R. Miyamoto, B. Cheymol, R. De Prisco, M. Eshraqi, A. Ponton, E. Sargsyan ESS, Lund, Sweden I. Bustinduy ESS Bilbao, Bilbao, Spain
	The front-end of a hadron linac typically has a transient time during turning on and off and bunches in the head and tail of a pulse from this period likely have wrong parameters and a risk to cause beam losses. A risk of losses must be avoided as possible in a high power machine so these bunches are removed with deflectors called choppers in the ESS Linac. From experiences of other machines, a rise time of a chopper as fast as one RF period (2.84~ns for ESS) is challenging to achieve and not necessarily needed with no ring to inject like ESS, and hence a 10~ns rise time is planned for a chopper in the medium energy beam transport of ESS. This, however, means that several bunches receive intermediate deflections and may propagate with large trajectory excursions. This paper studies dynamics of such partially chopped bunches in detail to ensure no significant loss is caused by them.

MOPP080	Beam Dynamics Study for RAON Superconducting Linac	linac, ion, proton, quadrupole	239
	H. Jang, H.J. Kim IBS, Daejeon, Republic of Korea J.G. Hwang KNU, Deagu, Republic of Korea B.H. Oh POSTECH, Pohang, Kyungbuk, Republic of Korea
	Rare Isotope Science Project (RISP) in Korea is going to build an ion accelerator, RAON which can generate and accelerate various stable ions such as uranium, proton, xenon and rare isotopes such as tin, nickel. Linear accelerators of RAON adopted superconducting RF cavities and warm quadruple doublet structure. In RAON, there are two low energy linacs which can accelerate the Uranium beam from 0.5MeV/u to 17.5MeV/u, charge stripping sections and one high energy linac which can accelerate the Uranium beam up to 200MeV/u. Due to the diversity of planned ions and isotopes, their A/q range lies widely from 1 to 8. As a result, the research related with linac lattice design and beam dynamics is one of the important topics to build RAON. In this presentation the current status of RAON linac lattice design and the beam dynamics simulation results for acceleration of various ions will be described.

MOPP097	The Physics Programme of Next MICE Step IV	emittance, experiment, scattering, solenoid	285
	V. Blackmore JAI, Oxford, United Kingdom
	Funding: DOE, NSF, STFC, INFN and more The international Muon Ionisation Cooling Experiment (MICE) is progressing toward a full demonstration of the feasibility of the cooling technology required for neutrino physics and muon colliders. Step IV will provide the first precise measurements of emittance and determine the influence of material properties on emittance reduction. The physics programme of the Step IV measurements is described in detail, along with a longer term view to demonstrating and studying (sustainable) ionisation cooling with re-acceleration. The abstract is submitted by the chair of the MICE Speakers Bureau. The presentation will be delivered by Dr Victoria Blackmore (Oxford) Promotion to Oral presentation is be most welcome.

TUPP064	Zero-Current Longitudinal Beam Dynamics	resonance, damping, cavity, linac	572
	J.-M. Lagniel GANIL, Caen, France
	In linacs, the longitudinal focalization is done by nonlinear forces and the acceleration induces a damping of the phase oscillations. The longitudinal beam dynamics is therefore complex, even when the nonlinear space-charge forces are ignored. The three different ways to study and understand this zero-current longitudinal beam dynamics will be presented and compared.

TUPP090	Spatially Periodic RF Quadrupole LINAC	quadrupole, focusing, linac, ion	634
	A.S. Plastun, A. Kolomiets ITEP, Moscow, Russia
	Spatially-periodic RF quadrupole structure is proposed as second section of front end of ion linac. It consists of conventional drift tubes and RF quadrupoles. Quadrupoles are 4-vane segments with nonzero electric potential on the longitudinal axis. Thus the accelerating electric field is formed between drift tubes and RF quadrupoles. Moreover accelerating field can be provided even inside the RF quadrupoles. It allows building structures with different focusing lattices and provides high energy gain rate.
	Poster TUPP090 [7.706 MB]

TUPP119	Design Studies for Medium and High beta SCRF Cavities for Indian Spallation Neutron Source	cavity, linac, HOM, quadrupole	699
	A.R. Jana, V. Kumar RRCAT, Indore, India
	There is a plan to build a 1 GeV H⁻ linac for the proposed Indian Spallation Neutron Source (ISNS) at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore. The medium and high energy section of the ISNS linac will consist of beta_g=0.61, as well as beta_g = 0.9, 650 MHz, 5-cell superconducting radiofrequency (SCRF) cavities, for which detailed electromagnetic design studies have been performed. During our design study, we have evolved a generalized procedure for the optimization of geometrical parameters of multi-cell SCRF cavities. Studies on higher order modes supported by the cavity and its effect on beam dynamics, as well as on heat load to the cavity have been performed, which constitute an important aspect of the design study. Finally, detailed studies on Lorentz Force Detuning (LFD) have been performed, and design of the cavity has been optimized to minimize the effect due to the LFD. The paper discussed the details of the calculations and the studies that have been performed during the design study.

THPP035	Deceleration Measurements of an Electron Beam in the CLIC Test Facility 3	electron, quadrupole, acceleration, linear-collider	920
	R.L. Lillestøl, S. Döbert CERN, Geneva, Switzerland E. Adli University of Oslo, Oslo, Norway
	The Test Beam Line at the CLIC Test Facility 3 at CERN is a proof-of-principle of the future CLIC decelerators, which will extract a large amount of beam energy for acceleration of the main CLIC beams. The current beamline consists of a FODO lattice with 13 Power Extraction and Transfer Structures (PETS). We discuss beam deceleration measurements of up to 37 %, taking into account effects from the bunch length and the bunch phase. The 12 GHz phase is reproduced based on measurements in a PETS with an uncombined beam. The spectrometer measurements are also compared to predictions based on the beam current and on the produced rf power in the PETS, as well as particle tracking simulations with the Placet code.

Paper

Title

Other Keywords

Page

MOPP003

A Compact Linac Design for an Accelerator Driven System

linac, cavity, cryomodule, focusing

52

B. Mustapha, S.V. Kutsaev, J.A. Nolen, P.N. Ostroumov
ANL, Argonne, USA

Funding: This work was supported by the U.S. Department of Energy, Office of Nuclear Physics, under Contract No. DE-AC02-06CH11357.
A compact linac design has been developed for an Accelerator Driven System (ADS). The linac is under 150 meters in length and comprises a radio-frequency quadrupole (RFQ) and 20 superconducting modules. Three types of half-wave cavities and two types of elliptical cavities have been designed and optimized for high performance at frequencies of 162.5, 325 and 650 MHz. The lattice is being designed and optimized for operation with a peak power of 25 MW for a 25 mA – 1 GeV proton beam. The cavities RF design as well as the linac lattice will be presented along with end-to-end beam dynamics simulations for beam currents ranging from 0 to 25 mA.

MOPP039

Dynamics of Bunches Partially Chopped with the MEBT Chopper in the ESS Linac

linac, DTL, simulation, quadrupole

146

R. Miyamoto, B. Cheymol, R. De Prisco, M. Eshraqi, A. Ponton, E. Sargsyan
ESS, Lund, Sweden
I. Bustinduy
ESS Bilbao, Bilbao, Spain

The front-end of a hadron linac typically has a transient time during turning on and off and bunches in the head and tail of a pulse from this period likely have wrong parameters and a risk to cause beam losses. A risk of losses must be avoided as possible in a high power machine so these bunches are removed with deflectors called choppers in the ESS Linac. From experiences of other machines, a rise time of a chopper as fast as one RF period (2.84~ns for ESS) is challenging to achieve and not necessarily needed with no ring to inject like ESS, and hence a 10~ns rise time is planned for a chopper in the medium energy beam transport of ESS. This, however, means that several bunches receive intermediate deflections and may propagate with large trajectory excursions. This paper studies dynamics of such partially chopped bunches in detail to ensure no significant loss is caused by them.

MOPP080

Beam Dynamics Study for RAON Superconducting Linac

linac, ion, proton, quadrupole

239

H. Jang, H.J. Kim
IBS, Daejeon, Republic of Korea
J.G. Hwang
KNU, Deagu, Republic of Korea
B.H. Oh
POSTECH, Pohang, Kyungbuk, Republic of Korea

Rare Isotope Science Project (RISP) in Korea is going to build an ion accelerator, RAON which can generate and accelerate various stable ions such as uranium, proton, xenon and rare isotopes such as tin, nickel. Linear accelerators of RAON adopted superconducting RF cavities and warm quadruple doublet structure. In RAON, there are two low energy linacs which can accelerate the Uranium beam from 0.5MeV/u to 17.5MeV/u, charge stripping sections and one high energy linac which can accelerate the Uranium beam up to 200MeV/u. Due to the diversity of planned ions and isotopes, their A/q range lies widely from 1 to 8. As a result, the research related with linac lattice design and beam dynamics is one of the important topics to build RAON. In this presentation the current status of RAON linac lattice design and the beam dynamics simulation results for acceleration of various ions will be described.

MOPP097

The Physics Programme of Next MICE Step IV

emittance, experiment, scattering, solenoid

285

V. Blackmore
JAI, Oxford, United Kingdom

Funding: DOE, NSF, STFC, INFN and more
The international Muon Ionisation Cooling Experiment (MICE) is progressing toward a full demonstration of the feasibility of the cooling technology required for neutrino physics and muon colliders. Step IV will provide the first precise measurements of emittance and determine the influence of material properties on emittance reduction. The physics programme of the Step IV measurements is described in detail, along with a longer term view to demonstrating and studying (sustainable) ionisation cooling with re-acceleration.
The abstract is submitted by the chair of the MICE Speakers Bureau.
The presentation will be delivered by Dr Victoria Blackmore (Oxford)
Promotion to Oral presentation is be most welcome.

TUPP064

Zero-Current Longitudinal Beam Dynamics

resonance, damping, cavity, linac

572

J.-M. Lagniel
GANIL, Caen, France

In linacs, the longitudinal focalization is done by nonlinear forces and the acceleration induces a damping of the phase oscillations. The longitudinal beam dynamics is therefore complex, even when the nonlinear space-charge forces are ignored. The three different ways to study and understand this zero-current longitudinal beam dynamics will be presented and compared.

TUPP090

Spatially Periodic RF Quadrupole LINAC

quadrupole, focusing, linac, ion

634

A.S. Plastun, A. Kolomiets
ITEP, Moscow, Russia

Spatially-periodic RF quadrupole structure is proposed as second section of front end of ion linac. It consists of conventional drift tubes and RF quadrupoles. Quadrupoles are 4-vane segments with nonzero electric potential on the longitudinal axis. Thus the accelerating electric field is formed between drift tubes and RF quadrupoles. Moreover accelerating field can be provided even inside the RF quadrupoles. It allows building structures with different focusing lattices and provides high energy gain rate.

Poster TUPP090 [7.706 MB]

TUPP119

Design Studies for Medium and High beta SCRF Cavities for Indian Spallation Neutron Source

cavity, linac, HOM, quadrupole

699

A.R. Jana, V. Kumar
RRCAT, Indore, India

There is a plan to build a 1 GeV H⁻ linac for the proposed Indian Spallation Neutron Source (ISNS) at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore. The medium and high energy section of the ISNS linac will consist of beta_g=0.61, as well as beta_g = 0.9, 650 MHz, 5-cell superconducting radiofrequency (SCRF) cavities, for which detailed electromagnetic design studies have been performed. During our design study, we have evolved a generalized procedure for the optimization of geometrical parameters of multi-cell SCRF cavities. Studies on higher order modes supported by the cavity and its effect on beam dynamics, as well as on heat load to the cavity have been performed, which constitute an important aspect of the design study. Finally, detailed studies on Lorentz Force Detuning (LFD) have been performed, and design of the cavity has been optimized to minimize the effect due to the LFD. The paper discussed the details of the calculations and the studies that have been performed during the design study.

THPP035

Deceleration Measurements of an Electron Beam in the CLIC Test Facility 3

electron, quadrupole, acceleration, linear-collider

920

R.L. Lillestøl, S. Döbert
CERN, Geneva, Switzerland
E. Adli
University of Oslo, Oslo, Norway

The Test Beam Line at the CLIC Test Facility 3 at CERN is a proof-of-principle of the future CLIC decelerators, which will extract a large amount of beam energy for acceleration of the main CLIC beams. The current beamline consists of a FODO lattice with 13 Power Extraction and Transfer Structures (PETS). We discuss beam deceleration measurements of up to 37 %, taking into account effects from the bunch length and the bunch phase. The 12 GHz phase is reproduced based on measurements in a PETS with an uncombined beam. The spectrometer measurements are also compared to predictions based on the beam current and on the produced rf power in the PETS, as well as particle tracking simulations with the Placet code.