LINAC2014 - List of Authors (Ponton, A.)

Paper	Title	Page
MOPP039	Dynamics of Bunches Partially Chopped with the MEBT Chopper in the ESS Linac	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.

TUPP025	Progress on ESS Medium Energy Beam Transport	484
	I. Bustinduy, D. Fernandez-Cañoto, N. Garmendia, A. Ghiglino, O. González, P.J. González, Z. Izaola, I. Madariaga, M. Magan, L. Muguira, J.L. Muñoz, I. Rueda, F. Sordo, S. Varnasseri, R. Vivanco ESS Bilbao, Bilbao, Spain M. Eshraqi, R. Miyamoto, A. Ponton ESS, Lund, Sweden
	The considered versatile ESS MEBT is being designed to achieve four main goals: First, to contain a fast chopper and its correspondent beam dump, that could serve in the commissioning as well as in the ramp up phases. A detailed study of the chopper rise time effects on the loss budget will be presented. Second, to serve as a halo scraping section by means of various adjustable blades. Third, to measure the beam phase and proﬁle between the RFQ and the DTL, along with other beam monitors. And ﬁnally, to match the RFQ output beam characteristics to the DTL input both transversally and longitudinally. For this purpose a set of eleven quadrupoles is used to match the beam characteristics transversally, combined with three 352.2 MHz CCL type buncher cavities, which are used to adjust the beam in order to fulfil the required longitudinal parameters. A thorough study on the optimal input beam parameters will be discussed. Quadrupole design update will be presented along with new RF measurements over the buncher prototype. Finally, updated results will be presented on the chopper and beam-dump system.
	Poster TUPP025 [5.596 MB]

TUPP039	Accuracy Determination of the ESS MEBT Emittance Measurements	519
	B. Cheymol, A. Ponton ESS, Lund, Sweden
	The European Spallation Source MEBT will be equipped with a full set of diagnostics in order to characterize the bean properties before the injection in the DTL. The 6D phase space of the beam shall be characterize during the commissioning of the normal conducting as well as on regular basis during retuning phase of the machine. In this paper we will discuss the accuracy of the transverse emittance measurement that will be performed with the slit-grid method. The slit geometric parameters have been determined in order to achieve the required resolution and sensitivity. Scattering effects at the slit have been considered to determine the emittance measurement accuracy.

THPP043	Benchmark of the Beam Dynamics Code DYNAC Using the ESS Proton Linac	945
THPOL11	use link to see paper's listing under its alternate paper code
	E. Tanke, R. De Prisco, M. Eshraqi, R. Miyamoto, A. Ponton, E. Sargsyan ESS, Lund, Sweden S. Valero CEA, Gif-sur-Yvette, France
	The beam dynamics code DYNAC is benchmarked using the ESS Proton Linac. Recent work on improvements in the code, including of the RFQ model, is discussed. The three space charge routines contained in DYNAC, including a 3D version, have remained unchanged. The code contains a numerical method, capable of simulating a multi-charge state ion beam in accelerating elements. In addition, protons, single charge state heavy ions and non-relativistic electrons in accelerating elements can be modeled using an analytical method. The benchmark will include comparisons of both methods with the beam dynamics models in use at ESS: TraceWin and Toutatis. As this analytical method used in DYNAC is fast, it is a prime candidate for use as an online beam simulation tool.

THPP044	ESS Normal Conducting Linac Status and Plans	948
	A. Ponton, B. Cheymol, R. De Prisco, M. Eshraqi, R. Miyamoto, E. Sargsyan ESS, Lund, Sweden G. Bourdelle, M. Desmons, A. France, O. Piquet, B. Pottin CEA/DSM/IRFU, France I. Bustinduy, P.J. González, J.L. Muñoz, I. Rueda, F. Sordo ESS Bilbao, Bilbao, Spain L. Celona, S. Gammino, L. Neri INFN/LNS, Catania, Italy M. Comunian, F. Grespan, A. Pisent, C. R. Roncolato INFN/LNL, Legnaro (PD), Italy P. Mereu INFN-Torino, Torino, Italy
	The ESS Normal Conducting (NC) linac is composed of an ion source, a Low Energy Beam Transport line, a Radio Frequency Quarupole (RFQ), a Medium Energy Beam Transport Line (MEBT) and a Drift Tube Linac (DTL). It creates, bunches and accelerates the proton beam up to 90 MeV before injecting into the superconducting linac which will deliver a 5 MW beam onto the neutron production target. The construction of the NC linac is part of a broad collaboration involving experts of various Labs in Europe. The technical chalenges and the collaboration strategy for the NC linac will be presented.

Paper

Title

Page

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

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.

TUPP025

Progress on ESS Medium Energy Beam Transport

484

I. Bustinduy, D. Fernandez-Cañoto, N. Garmendia, A. Ghiglino, O. González, P.J. González, Z. Izaola, I. Madariaga, M. Magan, L. Muguira, J.L. Muñoz, I. Rueda, F. Sordo, S. Varnasseri, R. Vivanco
ESS Bilbao, Bilbao, Spain
M. Eshraqi, R. Miyamoto, A. Ponton
ESS, Lund, Sweden

The considered versatile ESS MEBT is being designed to achieve four main goals: First, to contain a fast chopper and its correspondent beam dump, that could serve in the commissioning as well as in the ramp up phases. A detailed study of the chopper rise time effects on the loss budget will be presented. Second, to serve as a halo scraping section by means of various adjustable blades. Third, to measure the beam phase and proﬁle between the RFQ and the DTL, along with other beam monitors. And ﬁnally, to match the RFQ output beam characteristics to the DTL input both transversally and longitudinally. For this purpose a set of eleven quadrupoles is used to match the beam characteristics transversally, combined with three 352.2 MHz CCL type buncher cavities, which are used to adjust the beam in order to fulfil the required longitudinal parameters. A thorough study on the optimal input beam parameters will be discussed. Quadrupole design update will be presented along with new RF measurements over the buncher prototype. Finally, updated results will be presented on the chopper and beam-dump system.

Poster TUPP025 [5.596 MB]

TUPP039

Accuracy Determination of the ESS MEBT Emittance Measurements

519

B. Cheymol, A. Ponton
ESS, Lund, Sweden

The European Spallation Source MEBT will be equipped with a full set of diagnostics in order to characterize the bean properties before the injection in the DTL. The 6D phase space of the beam shall be characterize during the commissioning of the normal conducting as well as on regular basis during retuning phase of the machine. In this paper we will discuss the accuracy of the transverse emittance measurement that will be performed with the slit-grid method. The slit geometric parameters have been determined in order to achieve the required resolution and sensitivity. Scattering effects at the slit have been considered to determine the emittance measurement accuracy.

THPP043

Benchmark of the Beam Dynamics Code DYNAC Using the ESS Proton Linac

945

THPOL11

use link to see paper's listing under its alternate paper code

E. Tanke, R. De Prisco, M. Eshraqi, R. Miyamoto, A. Ponton, E. Sargsyan
ESS, Lund, Sweden
S. Valero
CEA, Gif-sur-Yvette, France

The beam dynamics code DYNAC is benchmarked using the ESS Proton Linac. Recent work on improvements in the code, including of the RFQ model, is discussed. The three space charge routines contained in DYNAC, including a 3D version, have remained unchanged. The code contains a numerical method, capable of simulating a multi-charge state ion beam in accelerating elements. In addition, protons, single charge state heavy ions and non-relativistic electrons in accelerating elements can be modeled using an analytical method. The benchmark will include comparisons of both methods with the beam dynamics models in use at ESS: TraceWin and Toutatis. As this analytical method used in DYNAC is fast, it is a prime candidate for use as an online beam simulation tool.

THPP044

ESS Normal Conducting Linac Status and Plans

948

A. Ponton, B. Cheymol, R. De Prisco, M. Eshraqi, R. Miyamoto, E. Sargsyan
ESS, Lund, Sweden
G. Bourdelle, M. Desmons, A. France, O. Piquet, B. Pottin
CEA/DSM/IRFU, France
I. Bustinduy, P.J. González, J.L. Muñoz, I. Rueda, F. Sordo
ESS Bilbao, Bilbao, Spain
L. Celona, S. Gammino, L. Neri
INFN/LNS, Catania, Italy
M. Comunian, F. Grespan, A. Pisent, C. R. Roncolato
INFN/LNL, Legnaro (PD), Italy
P. Mereu
INFN-Torino, Torino, Italy

The ESS Normal Conducting (NC) linac is composed of an ion source, a Low Energy Beam Transport line, a Radio Frequency Quarupole (RFQ), a Medium Energy Beam Transport Line (MEBT) and a Drift Tube Linac (DTL). It creates, bunches and accelerates the proton beam up to 90 MeV before injecting into the superconducting linac which will deliver a 5 MW beam onto the neutron production target. The construction of the NC linac is part of a broad collaboration involving experts of various Labs in Europe. The technical chalenges and the collaboration strategy for the NC linac will be presented.