LINAC2014 - List of Keywords (cryogenics)

Paper	Title	Other Keywords	Page
MOPP026	Actively Cooled RF Power Coupler : Theoretical and Experimental Studies	cryomodule, cavity, proton, linac	111
	R. Bonomi, V. Parma CERN, Geneva, Switzerland
	In cryostats for Super-conducting Radio Frequency Cavities, the heat loads introduced by the high-power RF couplers represent an important fraction of the overall static thermal budget. Working at low operating temperature benefits from a reduced surface resistance (low dynamic losses) but is penalized by the high refrigeration cost. The external conductor of RF coaxial couplers provides a direct conduction path from ambient to cryogenic temperature plus is heated by resistive power deposition. Heat interception is therefore essential to contain heat in-leaks: a double-walled external conductor with a properly designed gas cooling effectively reduces heat loads to the cold bath by 1 order of magnitude. This paper presents the thermal design of the RF power coupler of the Superconducting Proton Linac (SPL) at CERN, featuring a helium vapour cooling between 4.5 K and ambient temperature. Numerical models, which can be used as design tools for other applications, have been developed to assess efficiency and thermal performance. A full-size mock-up cooled by nitrogen has been built for experimental validation. Comparison between calculations and measurements is presented and discussed.

TUIOC03	Nb3Sn - Present Status and Potential as an Alternative SRF Material	cavity, niobium, linac, SRF	431
	S. Posen, M. Liepe Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Nb₃Sn is a material that has the potential to have a transformative impact on SRF linacs. Due to its large critical temperature of approximately 18 K, Nb₃Sn cavities can have far smaller surface resistances at a given temperature than standard Nb cavities. This could significantly reduce the costs for infrastructure and power in cryoplants for large CW linacs. In addition, the predicted superheating field of Nb₃Sn is approximately double that of Nb, potentially doubling the maximum energy gradient. This would significantly decrease the size and cost of high energy linacs. In this work, we present recent progress in research and development for this promising material.
	Slides TUIOC03 [3.357 MB]
	Poster TUIOC03 [2.046 MB]

TUPP001	Cryogenic Performance of a New 72 MHz Quarter-Wave Resonator Cryomodule	cryomodule, cavity, solenoid, linac	437
	Z.A. Conway, G.L. Cherry, R.L. Fischer, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.H. Kim, S.W.T. MacDonald, R.C. Murphy, P.N. Ostroumov, C.E. Peters, M.A. Power, T. Reid, J.R. Specht ANL, Argonne, Illinois, USA
	Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under contract number DE-AC02-06CH11357. The Argonne National Laboratory ATLAS accelerator’s Intensity and Efficiency Upgrade project has been successfully finished [1]. This upgrade substantially increases beam currents for experimenters working with the existing stable and in-flight rare isotope beams and for the neutron rich beams from the Californium Rare Isotope Breeder upgrade. A major portion of this project involved the replacement of three existing cryomodules, containing 18 superconducting (SC) accelerator cavities and 9 superconducting solenoids, with a single cryomodule containing 7 SC 72.75 MHz accelerator cavities optimized for ion velocities of 7.7% the speed of light and 4 SC solenoids all operating at 4.5 K. This paper reports the measured thermal load to the 4 K and 80 K coolant streams and compares these results to the pre-upgrade cryogenic system.

TUPP068	New SRF Facility at KEK for Mass-Production Study in Collaboration with Industries	cryomodule, SRF, cavity, operation	584
	H. Hayano KEK, Ibaraki, Japan
	The construction of the new SRF facility next to the KEK-STF facility has started from 2014 for the mass-production study of SRF accelerators in collaboration with industries. The new building for this facility has the dimension of 80 m x 30 m, and the plan is to install clean-room for cavity-string assembly, cryomodule-assembly facility, cryogenic system, vertical test facility, cryomodule test facility, input coupler process facility, cavity Electro-Polishing (EP) facility, and control-room/office-rooms in it. The purpose of this new SRF facility is to establish a close collaboration between SRF researchers and industries in order to prepare for the upcoming large-scale future SRF project, like ILC. This paper describes the infra-structure detail and the plan to utilize for future SRF accelerators.

TUPP082	The MYRRHA Spoke Cryomodule Design	cavity, cryomodule, linac, framework	613
	H. Saugnac, J.-L. Biarrotte, S. Blivet, P. Duchesne, N. Gandolfo, J. Lesrel, G. Olry, E. Rampnoux, D. Reynet IPN, Orsay, France
	In the framework of the MAX project, dedicated to the detailed study of the MYRRHA facility LINAC, the engineering study of the ‘Spoke’ cavities cryomodule, situated in the low energy superconducting section, has been achieved. The beam optics, highly constrained by strong reliability requirements, leads to a modular cryomodule composed of two β=0.37, 352 MHz, single bar ‘Spoke’ cavity cooled at 2K. The power coupler design, not studied in detail under the MAX project, is directly taken from a 20 kW continuous wave 352 MHz coupler designed and successfully tested in the framework of the previous EUROTRANS and EURISOL projects. The cold tuning system is identical to the one designed for the ESS ‘Spoke’ cavities. We present in this paper, the RF, the mechanical and the thermal design of the complete cryomodule as well as the optimization and simulations of its individual components (Cavity, Cryostat, Tuning System…).

TUPP086	RAON Superconducting Radio Frequency Test Facility Construction	cavity, radiation, SRF, electron	625
	H. Kim, D. Jeon, Y.W. Jo, Y. Jung, S.A. Kim, W.K. Kim, S.J. Lee, S.W. Nam, G.-T. Park, J.H. Shin IBS, Daejeon, Republic of Korea
	Superconducting Radio Frequency (SRF) test facility for RAON is under construction process. It consists of cryogenic system, clean room for cavity process and assembles vertical test, horizontal test, and the radiation shield. The cryoplant has 330 W (4.5 K equivalent) which supplies 4.5K supercritical helium to the cavity test and cryomodule test bench. Clean rooms are for cavity process and assemble whose class is from 10 to 10000. The layout for the vertical and horizontal test bench is shown and the radiation shield for the test bench is shown to reduce X-ray coming from cavity. To estimate the thickness of concrete, radiation simulation is performed.

TUPP106	RF Characteristics of 20K Cryogenic 2.6-cell Photocathode RF-gun Test Cavity	cavity, gun, simulation, database	671
	T. Sakai, M. Inagaki, K. Nakao, K. Nogami, T. Tanaka LEBRA, Funabashi, Japan M.K. Fukuda, T. Takatomi, J. Urakawa, M. Yoshida KEK, Ibaraki, Japan T.S. Shintomi Nihon University, Tokyo, Japan
	Funding: This work was supported by Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan. The cryogenic C-band photocathode RF gun operating at 20K is under development at LEBRA in Nihon University. The RF gun is of the BNL-type 2.6-cell pillbox cavity with the resonant frequency of 5712 MHz. The 6N8 high purity OFC copper is used as the cavity material. From the theoretical evaluation of the anomalous skin effect, the quality factor Q of the cavity has been expected to be about 60000. Considering a low cooling capacity of the cryocooler system, initial operation of the RF gun is assumed at a duty factor of 0.01 %. The cavity basic design and the beam bunching simulation were carried out using SUPERFISH and General Particle Tracer (GPT). Machining of the cavity was carried out in KEK. The RF characteristics measured at room temperature and 20K will be reported.

TUPP109	Cryogenic Testing of High-Velocity Spoke Cavities	cavity, acceleration, proton, linac	677
	C.S. Hopper, J.R. Delayen, H. Park ODU, Norfolk, Virginia, USA J.R. Delayen, H. Park JLab, Newport News, Virginia, USA
	Spoke-loaded cavities are being investigated for the high-velocity regime. The relative compactness at low-frequency makes them attractive for applications requiring, or benefiting from, 4 K operation. Additionally, the large velocity acceptance makes them good candidates for the acceleration of high-velocity protons and ions. Here we present the results of cryogenic testing of a 325 MHz, β0 = 0.82 single-spoke cavity and a 500 MHz, β0 = 1 double-spoke cavity.

TUPP117	Commissioning of Vertical Test Stand Facility for 2 K Testing of Superconducting Cavities at RRCAT	cavity, radiation, shielding, controls	695
	S.C. Joshi, A. Chauhan, P. Fatnani, P.D. Gupta, M.K. Kumar, P.K. Kush, P. Mohania, S. Raghvendra, P. Shrivastava, S.K. Suhane RRCAT, Indore (M.P.), India
	Raja Ramanna Centre for Advanced Technology (RRCAT) has developed a 2K vertical Test Stand (VTS) facility for characterization of Superconducting RF (SCRF) cavities, under Indian Institution Fermilab Collaboration (IIFC). The VTS facility comprises of a large size liquid helium (LHe) cryostat, cryogenic system, RF power supply, control and data acquisition system and radiation monitoring system. It will facilitate testing of superconducting cavities of different frequencies ranging from 325 MHz low beta to 650 MHz / 1.3 GHz medium and high beta cavities. The helium vessel has a capacity to store up to 2900 litres of liquid Helium. The cryostat is installed inside a vertical pit. It is equipped with facilities for supply of liquid nitrogen and liquid helium and vacuum system for pumping out helium gas to lower the temperature of liquid helium bath down to 1.8 K. A 200 W, 1.3 GHz RF system has been indigenously developed for testing of the SCRF cavities. The VTS facility has now been commissioned and its performance validation has been successfully carried out by benchmarking it with respect to the facility at the Fermilab.

THIOA04	Superconducting Cavities and Cryomodules for Proton and Deuteron Linacs	cavity, cryomodule, linac, vacuum	801
	G. Devanz CEA/IRFU, Gif-sur-Yvette, France
	We review the recent advances in the design plans and test results of the superconducting structures for proton (ESS) and deuteron linacs (SPIRAL2, IFMIF). A variety of RF resonators are used for this purposes, from multicell elliptical cavities for the acceleration of pulsed proton beams to half and quarter wave resonators for CW deuteron beams. The increase in beam power with respect to previous generations of linacs brings new challenges to cavities and RF couplers. Test results of the available SRF prototypes and cryomodules of the aforementioned projects will be presented.
	Slides THIOA04 [6.785 MB]

THIOB01	Cryogenic Plants for SRF Linacs	vacuum, SRF, cryomodule, linac	811
	D. Arenius JLab, Newport News, Virginia, USA
	Review of the types of considerations that go into cryo-plant design. Arenius is a world expert on this topic and has led the completion of the upgraded cryo-plant at Jefferson Lab, and has recently provided substantial input on this question to the new LCLS II project.
	Slides THIOB01 [4.382 MB]

THIOB02	SPIRAL2 Cryomodule Production Result and Analysis	cryomodule, cavity, operation, linac	814
	P.-E. Bernaudin, R. Ferdinand GANIL, Caen, France P. Bosland, C. Marchand CEA/IRFU, Gif-sur-Yvette, France Y. Gómez Martínez LPSC, Grenoble Cedex, France D. Longuevergne, G. Olry IPN, Orsay, France
	The production and qualification of the SPIRAL2 cryomodules are close to the end. Their performances are now well established. This paper will explain the path followed to the good achievements, and show some statistical analyses to be used for future projects. How far can we push the performances? What cryogenics consumption shall we take as design values?
	Slides THIOB02 [2.864 MB]

THPP041	The Accelerator Cryoplant at ESS	controls, operation, cryomodule, linac	939
	P. Arnold, J. Fydrych, W. Hees, J.M. Jurns, X. Wang, J.G. Weisend ESS, Lund, Sweden
	The European Spallation Source (ESS) is a neutron science facility funded by a collaboration of 17 European countries currently under design and construction in Lund, Sweden. Cryogenic cooling is vital particularly for the linear accelerator, producing a 5 MW beam of 2.0 GeV protons to strike a rotating tungsten target. The cryogenic section of the linac comprises cryomodules with superconducting RF cavities that require helium cooling at 2.0 K, shield cooling at ~40 K and liquid helium for power coupler cooling. An extensive cryogenic distribution system connects the cryomodules with the linac cryoplant. With estimated electricity consumption of up to 3 MW this plant will be one of the major power consumers at ESS. Turndown modes and the intrinsic uncertainties regarding heat loads drive the need for high plant efficiency not only during full load operation but also at reduced performance. Together with flexibility and reliability over a long operation period these are the key challenges that will be addressed in this paper.
	Poster THPP041 [4.141 MB]

THPP135	Recent Improvements to Software Used for Optimization of SRF Linacs	cryomodule, cavity, linac, SRF	1174
	T. Powers JLab, Newport News, Virginia, USA
	Funding: Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. This work describes a software tool that allows one to vary parameters and understand the effects on the optimized costs of construction plus 10 year operations of an SRF linac. The program includes estimates for the associated cryogenic facility, and controls hardware, where operation costs includes the cost of the electrical utilities but not the labor or other costs. The software interface provides the ability to vary the cost of the different aspects of the machine as well as to change the cryomodule and cavity types. Additionally, this work will describe the recent improvements to the software that allow one to estimate the costs of energy recovery based linacs and to enter arbitrary values of the low field Qo and Qo slope. The initial goal was to convert a spreadsheet format to a graphical interface to allow the ability to sweep different parameter sets. The tools also allow one to compare the cost of the different facets of the machine design and operations so as to better understand the tradeoffs. An example of how it was used to investigate the cost optimization tradeoffs for the LCLS 2 linac will also be presented.

Paper

Title

Other Keywords

Page

MOPP026

Actively Cooled RF Power Coupler : Theoretical and Experimental Studies

cryomodule, cavity, proton, linac

111

R. Bonomi, V. Parma
CERN, Geneva, Switzerland

In cryostats for Super-conducting Radio Frequency Cavities, the heat loads introduced by the high-power RF couplers represent an important fraction of the overall static thermal budget. Working at low operating temperature benefits from a reduced surface resistance (low dynamic losses) but is penalized by the high refrigeration cost. The external conductor of RF coaxial couplers provides a direct conduction path from ambient to cryogenic temperature plus is heated by resistive power deposition. Heat interception is therefore essential to contain heat in-leaks: a double-walled external conductor with a properly designed gas cooling effectively reduces heat loads to the cold bath by 1 order of magnitude. This paper presents the thermal design of the RF power coupler of the Superconducting Proton Linac (SPL) at CERN, featuring a helium vapour cooling between 4.5 K and ambient temperature. Numerical models, which can be used as design tools for other applications, have been developed to assess efficiency and thermal performance. A full-size mock-up cooled by nitrogen has been built for experimental validation. Comparison between calculations and measurements is presented and discussed.

TUIOC03

Nb3Sn - Present Status and Potential as an Alternative SRF Material

cavity, niobium, linac, SRF

431

S. Posen, M. Liepe
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Nb₃Sn is a material that has the potential to have a transformative impact on SRF linacs. Due to its large critical temperature of approximately 18 K, Nb₃Sn cavities can have far smaller surface resistances at a given temperature than standard Nb cavities. This could significantly reduce the costs for infrastructure and power in cryoplants for large CW linacs. In addition, the predicted superheating field of Nb₃Sn is approximately double that of Nb, potentially doubling the maximum energy gradient. This would significantly decrease the size and cost of high energy linacs. In this work, we present recent progress in research and development for this promising material.

Slides TUIOC03 [3.357 MB]

Poster TUIOC03 [2.046 MB]

TUPP001

Cryogenic Performance of a New 72 MHz Quarter-Wave Resonator Cryomodule

cryomodule, cavity, solenoid, linac

437

Z.A. Conway, G.L. Cherry, R.L. Fischer, S.M. Gerbick, M. Kedzie, M.P. Kelly, S.H. Kim, S.W.T. MacDonald, R.C. Murphy, P.N. Ostroumov, C.E. Peters, M.A. Power, T. Reid, J.R. Specht
ANL, Argonne, Illinois, USA

Funding: This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics, under contract number DE-AC02-06CH11357.
The Argonne National Laboratory ATLAS accelerator’s Intensity and Efficiency Upgrade project has been successfully finished [1]. This upgrade substantially increases beam currents for experimenters working with the existing stable and in-flight rare isotope beams and for the neutron rich beams from the Californium Rare Isotope Breeder upgrade. A major portion of this project involved the replacement of three existing cryomodules, containing 18 superconducting (SC) accelerator cavities and 9 superconducting solenoids, with a single cryomodule containing 7 SC 72.75 MHz accelerator cavities optimized for ion velocities of 7.7% the speed of light and 4 SC solenoids all operating at 4.5 K. This paper reports the measured thermal load to the 4 K and 80 K coolant streams and compares these results to the pre-upgrade cryogenic system.

TUPP068

New SRF Facility at KEK for Mass-Production Study in Collaboration with Industries

cryomodule, SRF, cavity, operation

584

H. Hayano
KEK, Ibaraki, Japan

The construction of the new SRF facility next to the KEK-STF facility has started from 2014 for the mass-production study of SRF accelerators in collaboration with industries. The new building for this facility has the dimension of 80 m x 30 m, and the plan is to install clean-room for cavity-string assembly, cryomodule-assembly facility, cryogenic system, vertical test facility, cryomodule test facility, input coupler process facility, cavity Electro-Polishing (EP) facility, and control-room/office-rooms in it. The purpose of this new SRF facility is to establish a close collaboration between SRF researchers and industries in order to prepare for the upcoming large-scale future SRF project, like ILC. This paper describes the infra-structure detail and the plan to utilize for future SRF accelerators.

TUPP082

The MYRRHA Spoke Cryomodule Design

cavity, cryomodule, linac, framework

613

H. Saugnac, J.-L. Biarrotte, S. Blivet, P. Duchesne, N. Gandolfo, J. Lesrel, G. Olry, E. Rampnoux, D. Reynet
IPN, Orsay, France

In the framework of the MAX project, dedicated to the detailed study of the MYRRHA facility LINAC, the engineering study of the ‘Spoke’ cavities cryomodule, situated in the low energy superconducting section, has been achieved. The beam optics, highly constrained by strong reliability requirements, leads to a modular cryomodule composed of two β=0.37, 352 MHz, single bar ‘Spoke’ cavity cooled at 2K. The power coupler design, not studied in detail under the MAX project, is directly taken from a 20 kW continuous wave 352 MHz coupler designed and successfully tested in the framework of the previous EUROTRANS and EURISOL projects. The cold tuning system is identical to the one designed for the ESS ‘Spoke’ cavities. We present in this paper, the RF, the mechanical and the thermal design of the complete cryomodule as well as the optimization and simulations of its individual components (Cavity, Cryostat, Tuning System…).

TUPP086

RAON Superconducting Radio Frequency Test Facility Construction

cavity, radiation, SRF, electron

625

H. Kim, D. Jeon, Y.W. Jo, Y. Jung, S.A. Kim, W.K. Kim, S.J. Lee, S.W. Nam, G.-T. Park, J.H. Shin
IBS, Daejeon, Republic of Korea

Superconducting Radio Frequency (SRF) test facility for RAON is under construction process. It consists of cryogenic system, clean room for cavity process and assembles vertical test, horizontal test, and the radiation shield. The cryoplant has 330 W (4.5 K equivalent) which supplies 4.5K supercritical helium to the cavity test and cryomodule test bench. Clean rooms are for cavity process and assemble whose class is from 10 to 10000. The layout for the vertical and horizontal test bench is shown and the radiation shield for the test bench is shown to reduce X-ray coming from cavity. To estimate the thickness of concrete, radiation simulation is performed.

TUPP106

RF Characteristics of 20K Cryogenic 2.6-cell Photocathode RF-gun Test Cavity

cavity, gun, simulation, database

671

T. Sakai, M. Inagaki, K. Nakao, K. Nogami, T. Tanaka
LEBRA, Funabashi, Japan
M.K. Fukuda, T. Takatomi, J. Urakawa, M. Yoshida
KEK, Ibaraki, Japan
T.S. Shintomi
Nihon University, Tokyo, Japan

Funding: This work was supported by Photon and Quantum Basic Research Coordinated Development Program from the Ministry of Education, Culture, Sports, Science and Technology, Japan.
The cryogenic C-band photocathode RF gun operating at 20K is under development at LEBRA in Nihon University. The RF gun is of the BNL-type 2.6-cell pillbox cavity with the resonant frequency of 5712 MHz. The 6N8 high purity OFC copper is used as the cavity material. From the theoretical evaluation of the anomalous skin effect, the quality factor Q of the cavity has been expected to be about 60000. Considering a low cooling capacity of the cryocooler system, initial operation of the RF gun is assumed at a duty factor of 0.01 %. The cavity basic design and the beam bunching simulation were carried out using SUPERFISH and General Particle Tracer (GPT). Machining of the cavity was carried out in KEK. The RF characteristics measured at room temperature and 20K will be reported.

TUPP109

Cryogenic Testing of High-Velocity Spoke Cavities

cavity, acceleration, proton, linac

677

C.S. Hopper, J.R. Delayen, H. Park
ODU, Norfolk, Virginia, USA
J.R. Delayen, H. Park
JLab, Newport News, Virginia, USA

Spoke-loaded cavities are being investigated for the high-velocity regime. The relative compactness at low-frequency makes them attractive for applications requiring, or benefiting from, 4 K operation. Additionally, the large velocity acceptance makes them good candidates for the acceleration of high-velocity protons and ions. Here we present the results of cryogenic testing of a 325 MHz, β0 = 0.82 single-spoke cavity and a 500 MHz, β0 = 1 double-spoke cavity.

TUPP117

Commissioning of Vertical Test Stand Facility for 2 K Testing of Superconducting Cavities at RRCAT

cavity, radiation, shielding, controls

695

S.C. Joshi, A. Chauhan, P. Fatnani, P.D. Gupta, M.K. Kumar, P.K. Kush, P. Mohania, S. Raghvendra, P. Shrivastava, S.K. Suhane
RRCAT, Indore (M.P.), India

Raja Ramanna Centre for Advanced Technology (RRCAT) has developed a 2K vertical Test Stand (VTS) facility for characterization of Superconducting RF (SCRF) cavities, under Indian Institution Fermilab Collaboration (IIFC). The VTS facility comprises of a large size liquid helium (LHe) cryostat, cryogenic system, RF power supply, control and data acquisition system and radiation monitoring system. It will facilitate testing of superconducting cavities of different frequencies ranging from 325 MHz low beta to 650 MHz / 1.3 GHz medium and high beta cavities. The helium vessel has a capacity to store up to 2900 litres of liquid Helium. The cryostat is installed inside a vertical pit. It is equipped with facilities for supply of liquid nitrogen and liquid helium and vacuum system for pumping out helium gas to lower the temperature of liquid helium bath down to 1.8 K. A 200 W, 1.3 GHz RF system has been indigenously developed for testing of the SCRF cavities. The VTS facility has now been commissioned and its performance validation has been successfully carried out by benchmarking it with respect to the facility at the Fermilab.

THIOA04

Superconducting Cavities and Cryomodules for Proton and Deuteron Linacs

cavity, cryomodule, linac, vacuum

801

G. Devanz
CEA/IRFU, Gif-sur-Yvette, France

We review the recent advances in the design plans and test results of the superconducting structures for proton (ESS) and deuteron linacs (SPIRAL2, IFMIF). A variety of RF resonators are used for this purposes, from multicell elliptical cavities for the acceleration of pulsed proton beams to half and quarter wave resonators for CW deuteron beams. The increase in beam power with respect to previous generations of linacs brings new challenges to cavities and RF couplers. Test results of the available SRF prototypes and cryomodules of the aforementioned projects will be presented.

Slides THIOA04 [6.785 MB]

THIOB01

Cryogenic Plants for SRF Linacs

vacuum, SRF, cryomodule, linac

811

D. Arenius
JLab, Newport News, Virginia, USA

Review of the types of considerations that go into cryo-plant design. Arenius is a world expert on this topic and has led the completion of the upgraded cryo-plant at Jefferson Lab, and has recently provided substantial input on this question to the new LCLS II project.

Slides THIOB01 [4.382 MB]

THIOB02

SPIRAL2 Cryomodule Production Result and Analysis

cryomodule, cavity, operation, linac

814

P.-E. Bernaudin, R. Ferdinand
GANIL, Caen, France
P. Bosland, C. Marchand
CEA/IRFU, Gif-sur-Yvette, France
Y. Gómez Martínez
LPSC, Grenoble Cedex, France
D. Longuevergne, G. Olry
IPN, Orsay, France

The production and qualification of the SPIRAL2 cryomodules are close to the end. Their performances are now well established. This paper will explain the path followed to the good achievements, and show some statistical analyses to be used for future projects. How far can we push the performances? What cryogenics consumption shall we take as design values?

Slides THIOB02 [2.864 MB]

THPP041

The Accelerator Cryoplant at ESS

controls, operation, cryomodule, linac

939

P. Arnold, J. Fydrych, W. Hees, J.M. Jurns, X. Wang, J.G. Weisend
ESS, Lund, Sweden

The European Spallation Source (ESS) is a neutron science facility funded by a collaboration of 17 European countries currently under design and construction in Lund, Sweden. Cryogenic cooling is vital particularly for the linear accelerator, producing a 5 MW beam of 2.0 GeV protons to strike a rotating tungsten target. The cryogenic section of the linac comprises cryomodules with superconducting RF cavities that require helium cooling at 2.0 K, shield cooling at ~40 K and liquid helium for power coupler cooling. An extensive cryogenic distribution system connects the cryomodules with the linac cryoplant. With estimated electricity consumption of up to 3 MW this plant will be one of the major power consumers at ESS. Turndown modes and the intrinsic uncertainties regarding heat loads drive the need for high plant efficiency not only during full load operation but also at reduced performance. Together with flexibility and reliability over a long operation period these are the key challenges that will be addressed in this paper.

Poster THPP041 [4.141 MB]

THPP135

Recent Improvements to Software Used for Optimization of SRF Linacs

cryomodule, cavity, linac, SRF

1174

T. Powers
JLab, Newport News, Virginia, USA

Funding: Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
This work describes a software tool that allows one to vary parameters and understand the effects on the optimized costs of construction plus 10 year operations of an SRF linac. The program includes estimates for the associated cryogenic facility, and controls hardware, where operation costs includes the cost of the electrical utilities but not the labor or other costs. The software interface provides the ability to vary the cost of the different aspects of the machine as well as to change the cryomodule and cavity types. Additionally, this work will describe the recent improvements to the software that allow one to estimate the costs of energy recovery based linacs and to enter arbitrary values of the low field Qo and Qo slope. The initial goal was to convert a spreadsheet format to a graphical interface to allow the ability to sweep different parameter sets. The tools also allow one to compare the cost of the different facets of the machine design and operations so as to better understand the tradeoffs. An example of how it was used to investigate the cost optimization tradeoffs for the LCLS 2 linac will also be presented.