LINAC2014 - List of Authors (Cheymol, B.)

Paper	Title	Page
MOPP036	Estimation of the Thermal Load and Signal Level of the ESS Wire Scanner	137
	B. Cheymol ESS, Lund, Sweden
	The European Spallation Source (ESS), to be built in the south of Sweden, will use a 2 GeV superconducting linac to produce the worlds most powerful neutron source with a beam power of 5 MW. A number of wire scanners will be used to characterize the beam transverse profile. The design of the wire has to cope with the high power density of the beam and must satisfy the overall measurement robustness, accuracy and sensitivity for the commissioning and the regular retuning phase of the ESS linac. This paper describes the preliminary design of the wire scanner system in the normal conducing linac as well as in the superconducting linac.

MOPP037	Conceptual Design of the ESS DTL Faraday Cup	140
	B. Cheymol, E. Lundh ESS, Lund, Sweden
	The DTL section of the ESS linac will accelerate the beam form 3.6 MeV to 90 MeV at a peak current of 62.5 mA. It is foreseen to install after each DTL tank a Faraday cup for beam current and the beam transmission measurements during retuning phase. An energy degrader will be positioned in front of the in order to perform a low resolution phase scan of the DTL tank before injecting the beam in the downstream structure. This paper describes the preliminary studies of the Faraday cup, mainly focus on the energy degrader.

MOPP038	Longitudinal Bunch Profile Monitoring at the ESS Linac	143
	I. Dolenc Kittelmann, B. Cheymol ESS, Lund, Sweden
	The European Spallation Source (ESS), which is currently under construction, will be a neutron source based on 5MW, 2GeV proton linac. This high intensity linac will among other beam instrumentation require longitudinal bunch profile monitors. These shall be used during the commissioning phase and start-up periods for beam dynamics optimization and beam loss reduction. The paper focuses on the preliminary studies concerning the longitudinal bunch profile monitoring at the ESS linac.

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.

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.

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

Estimation of the Thermal Load and Signal Level of the ESS Wire Scanner

137

B. Cheymol
ESS, Lund, Sweden

The European Spallation Source (ESS), to be built in the south of Sweden, will use a 2 GeV superconducting linac to produce the worlds most powerful neutron source with a beam power of 5 MW. A number of wire scanners will be used to characterize the beam transverse profile. The design of the wire has to cope with the high power density of the beam and must satisfy the overall measurement robustness, accuracy and sensitivity for the commissioning and the regular retuning phase of the ESS linac. This paper describes the preliminary design of the wire scanner system in the normal conducing linac as well as in the superconducting linac.

MOPP037

Conceptual Design of the ESS DTL Faraday Cup

140

B. Cheymol, E. Lundh
ESS, Lund, Sweden

The DTL section of the ESS linac will accelerate the beam form 3.6 MeV to 90 MeV at a peak current of 62.5 mA. It is foreseen to install after each DTL tank a Faraday cup for beam current and the beam transmission measurements during retuning phase. An energy degrader will be positioned in front of the in order to perform a low resolution phase scan of the DTL tank before injecting the beam in the downstream structure. This paper describes the preliminary studies of the Faraday cup, mainly focus on the energy degrader.

MOPP038

Longitudinal Bunch Profile Monitoring at the ESS Linac

143

I. Dolenc Kittelmann, B. Cheymol
ESS, Lund, Sweden

The European Spallation Source (ESS), which is currently under construction, will be a neutron source based on 5MW, 2GeV proton linac. This high intensity linac will among other beam instrumentation require longitudinal bunch profile monitors. These shall be used during the commissioning phase and start-up periods for beam dynamics optimization and beam loss reduction. The paper focuses on the preliminary studies concerning the longitudinal bunch profile monitoring at the ESS linac.

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.

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.

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.