SRF2019 - List of Authors (Dziuba, F.D.)

Paper	Title	Page
MOP081	Considerations for Efficient RF Operation for the Advanced cw-Linac Demonstrator at GSI	267
	C. Burandt, K. Aulenbacher, W.A. Barth, F.D. Dziuba, V. Gettmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, S. Yaramyshev HIM, Mainz, Germany K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, M. Heilmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, A. Schnase, S. Yaramyshev GSI, Darmstadt, Germany K. Aulenbacher, F.D. Dziuba, S. Lauber, J. List IKP, Mainz, Germany M. Basten, M. Busch, H. Podlech, M. Schwarz IAP, Frankfurt am Main, Germany
	The FAIR@GSI accelerator facility will require the GSI-UNILAC to provide short heavy ion pulses of highest intensity at low repetition rate for injection into the 18 Tm synchrotron SIS18. However, successful physics programs like SHE (Super Heavy Elements) rely on the UNILAC providing for heavy ion beams of high average current and high duty factor. In the next future, a dedicated super-conducting (sc) cw-Linac should therefore deliver cw beams to the experiments associated with those programs. As a first step towards this goal, beam tests with a single sc Cross-bar H-mode (CH) cavity were successfully conducted in 2017/2018. Within the scope of an Advanced Demonstrator project, current activities now aim at a beam test of a full cryomodule with three sc CH cavities and a sc rebuncher. Given a limited amount of rf power available per cavity and the necessity to accelerate different ion species with different mass-to-charge ratios, the loaded quality factor Q of the different resonators has to be chosen very carefully. This contribution discusses the simulations performed in this context.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-MOP081
About •	paper received ※ 21 June 2019 paper accepted ※ 29 June 2019 issue date ※ 14 August 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP004	Latest Cryogenic Test Results of the Superconducting β=0.069 CH-cavities for the HELIAC-project	392
	M. Basten, M. Busch, T. Conrad, H. Podlech, M. Schwarz IAP, Frankfurt am Main, Germany K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, M. Heilmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, J. Salvatore, A. Schnase, S. Yaramyshev GSI, Darmstadt, Germany K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu HIM, Mainz, Germany K. Aulenbacher, S. Lauber IKP, Mainz, Germany F.D. Dziuba, J. List KPH, Mainz, Germany
	The upcoming FAIR (Facility for Antiproton and Ion Research) project at GSI will use the existing UNILAC (UNIversal Linear Accelerator) as an injector, reducing the beam time for the ambitious Super Heavy Element (SHE) program. To keep the UNILAC user program competitive a new superconducting (sc) continuous wave (cw) high intensity heavy ion LINAC should provide ion beams with max. duty factor above the coulomb barrier. The fundamental sc LINAC design comprises a low energy beam transport (LEBT)-section followed by a sc Drift Tube Linac (DTL) consisting of sc Crossbar-H-mode (CH) structures for acceleration up to 7.3 MeV/u. The latest milestones towards the new cw LINAC HELIAC (HELmholtz LInear ACcelerator) have been the successful tests and commissioning of the first demonstrator section with heavy ion beam in 2017 and 218 as well as the successful test under cryogenic conditions of the second CH-cavity in 2018. Now the third CH-cavity has been tested at cryogenic temperatures of 4 Kelvin at the Institute for Applied Physics (IAP) at Goethe University Frankfurt (GUF). The results of these measurements as well as the status of the HELIAC-project will be presented.
	Poster TUP004 [0.958 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-TUP004
About •	paper received ※ 22 June 2019 paper accepted ※ 30 June 2019 issue date ※ 14 August 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP098	Preparation for the Advanced Demonstrator Testing at GSI	698
	V. Gettmann, K. Aulenbacher, W.A. Barth, F.D. Dziuba, M. Heilmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, S. Yaramyshev GSI, Darmstadt, Germany K. Aulenbacher, W.A. Barth, F.D. Dziuba, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu HIM, Mainz, Germany K. Aulenbacher, F.D. Dziuba, S. Lauber IKP, Mainz, Germany M. Basten, H. Podlech, M. Schwarz IAP, Frankfurt am Main, Germany
	The superconducting (sc) heavy ion Helmholtz Linear Accelerator (HELIAC) is under development at GSI. As a first step, the cw-Linac demonstrator was the first part for the proposed cw-LINAC@GSI. A superconducting CH-cavity, embedded by two superconducting solenoids has been tested with beam in 2017/2018 successfully. The sc CH-structure, designed at Goethe-University of Frankfurt, is the key component and offers a variety of research and development. As a next step the first cryostat of the HELIAC, the so called Advanced Demonstrator will be tested in the same testing environment at GSI. Therefore, a bigger concrete Bunker as well as the connection to the cryo plant is under development. The cold string was assembled in a rehabilitated clean room at GSI. For future clean room assemblies a fully equipped clean room is under preparation at Helmholtz-Institut Mainz. The mechanical suspension, composed of hanging components on crossed steel ropes, is a reliable concept to prevent the displacement during cool down. The cryogenic systems as well as all other mechanical tasks were solved. These and the future Advanced Demonstrator preparation will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-TUP098
About •	paper received ※ 22 June 2019 paper accepted ※ 01 July 2019 issue date ※ 14 August 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THP101	Commissioning of a Cleanroom for SRF Activities at the Helmholtz Institute Mainz	1162
	T. Kürzeder, K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, R.G. Heine, S. Lauber, J. List, M. Miski-Oglu HIM, Mainz, Germany K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, S. Lauber, J. List, M. Miski-Oglu, S. Yaramyshev GSI, Darmstadt, Germany K. Aulenbacher, F.D. Dziuba, S. Lauber IKP, Mainz, Germany J. Conrad TU Darmstadt, Darmstadt, Germany R.G. Heine, F. Hug, J. List, T. Stengler KPH, Mainz, Germany
	A newly built cleanroom is under commissioning at the Helmholtz-Institute Mainz (HIM). In its ISO-class 6 area vacuum components and cavities can be cleaned in different ultrasonic baths and in a dedicated conductance rinsing bath. In the ISO-class 4 area a large vacuum oven offers the possibility for comprehensive drying. A high pressure rinsing cabinet (HPR) has been installed between the two cleanroom areas to be loaded and unloaded from both sides. Complete cold-strings have to be mounted in the ISO-class 4 area and to be rolled out of the cleanroom on a rail system installed on the floor. All installations and tools have been integrated to treat and assemble superconducting 217 MHz multigap crossbar cavities for the Helmholtz Linear Accelerator (HELIAC), which is under development by HIM and GSI. Those crossbar cavities have a diameter of 650 mm and a weight of up to 100 kg. The cleanroom will be also used for the Mainz Energy-Recovering Superconducting Accelerator (MESA) project, processing the TESLA/XFEL type 9-cell cavities and other beamline components. This paper reports on the commissioning of the cleanroom and shows the features of the different installations.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-THP101
About •	paper received ※ 23 June 2019 paper accepted ※ 01 July 2019 issue date ※ 14 August 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THP103	Reconstruction of the Longitudinal Phase Space for the Superconducting CW HELIAC	1173
SUSP038	use link to see paper's listing under its alternate paper code
	S. Lauber, K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, T. Kürzeder, J. List, M. Miski-Oglu HIM, Mainz, Germany K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, P. Forck, V. Gettmann, M. Heilmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, T. Sieber, S. Yaramyshev GSI, Darmstadt, Germany K. Aulenbacher, F.D. Dziuba, S. Lauber IKP, Mainz, Germany H. Podlech, M. Schwarz IAP, Frankfurt am Main, Germany
	The superconducting (SC) heavy ion HElmholtz LInear ACcelerator (HELIAC) is under development at GSI in Darmstadt in cooperation with Helmholtz Institute Mainz (HIM) and Goethe-University Frankfurt (GUF). A novel design is used for the accelerating cavities, namely SC continuous wave (CW) multigap Crossbar H-Mode cavities. For this a dedicated beam dynamics layout - the EQUidistant mUltigap Structure (EQUUS) - has been carried out a couple of years ago and is under further development. In December 2018 the GSI High Charge State Injector (HLI) delivered heavy ion beam to the already commissioned first of series superconducting RF cavity. Proper 6D-matching to the CH cavity demands sufficient beam characterisation. Slit-grid emittance measurements provided for the transverse phase space determination. By measuring the longitudinal projection of the bunch with a Feschenko Monitor (Beam Shape Monitor), the bunch profile was obtained. With a dedicated algorithm, the full longitudinal phase space at the HLI-exit could be reconstructed from a set of BSM measurements. The basic reconstruction method, all relevant BSM measurements and the resulting phase space reconstruction will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-THP103
About •	paper received ※ 19 June 2019 paper accepted ※ 29 June 2019 issue date ※ 14 August 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRCAA4	Progress in SRF CH-Cavities for the HELIAC CW Linac at GSI	1206
	M. Miski-Oglu, K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, T. Kürzeder, S. Lauber, J. List, S. Yaramyshev HIM, Mainz, Germany K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, M. Heilmann, T. Kürzeder, S. Lauber, J. List, A. Rubin, A. Schnase, S. Yaramyshev GSI, Darmstadt, Germany K. Aulenbacher, F.D. Dziuba, J. List KPH, Mainz, Germany M. Basten, M. Busch, T. Conrad, H. Podlech, M. Schwarz IAP, Frankfurt am Main, Germany S. Lauber IKP, Mainz, Germany
	The machine beam commissioning is a major milestone of the R&D for the superconducting heavy ion continuous wave linear accelerator HELIAC of Helmholtz Institute Mainz (HIM) and GSI developed in collaboration with IAP Goethe-University Frankfurt. During successful beam commissioning of the superconducting 15-gap Crossbar H-mode cavity at GSI Helmholtzzentrum für Schwerionenforschung heavy ions up to the design beam energy have been accelerated. The design acceleration gain of 3.5 MeV has been reached with full transmission for heavy ion beams of up to 1.5 particle mueA. We present fabrication experience and results of off-line and on-line cavity performance. The next step is the procurement and commissioning of so called ’Advanced Demonstrator’ - the first of series cryomodule for the entire accelerator HELIAC. Results of further Demonstrator beam tests, as well as the status of the Advanced demonstrator project will be reported.
	Slides FRCAA4 [9.864 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-FRCAA4
About •	paper received ※ 23 June 2019 paper accepted ※ 02 July 2019 issue date ※ 14 August 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP019	Surface Preparation and Optimization of SC CH Cavities	71
SUSP024	use link to see paper's listing under its alternate paper code
	P. Müller, M. Basten, M. Busch, T. Conrad, H. Podlech IAP, Frankfurt am Main, Germany K. Aulenbacher, F.D. Dziuba, M. Miski-Oglu HIM, Mainz, Germany W.A. Barth GSI, Darmstadt, Germany
	The Institute of Applied Physics (IAP) introduced the superconducting multi-gap CH-structure, which is mainly designed for low beta hadron acceleration. In 2017, a 217 MHz sc CH-structure was successfully tested with beam at GSI and multiple CH-structures are currently under development for the GSI cw linac. RF performance of all sc cavities are limited by the surface properties of the used material. Therefore, sufficient surface preparation and optimization is necessary to achieve optimal performance. Presently as standard procedure BCP and HPR is used for CH-cavities. Several surface treatments will be applied to the very first CH-prototype, a 360 MHz, 19-cell cavity. Prior to the first treatment, the status of the cavity was examined, including leak tests and performance tests at 4 and 2 K. This paper presents the performance development of a sc CH cavity depending on different preparation methods.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-MOP019
About •	paper received ※ 23 June 2019 paper accepted ※ 05 July 2019 issue date ※ 14 August 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP050	Modular Power Couplers for 217 MHz Superconducting CH-Cavities	168
SUSP034	use link to see paper's listing under its alternate paper code
	J. List, K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, T. Kürzeder, S. Lauber, M. Miski-Oglu HIM, Mainz, Germany K. Aulenbacher, W.A. Barth, C. Burandt, V. Gettmann, M. Heilmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, A. Schnase, S. Yaramyshev GSI, Darmstadt, Germany K. Aulenbacher, F.D. Dziuba, S. Lauber, J. List IKP, Mainz, Germany M. Basten, M. Busch, H. Podlech, M. Schwarz IAP, Frankfurt am Main, Germany
	The HELmholtz LInear ACcelerator (HELIAC) is being developed by a collaboration of HIM, GSI and the Goethe University of Frankfurt. It is a superconducting (sc), continuous wave (cw) heavy ion linac that comprises novel Crossbar H-mode (CH) cavities. In April 2017 and November/December 2018 the first sc CH-cavity of the linac was tested with beam. The first operations of the cavity showed, that the prototype of the rf power coupler needs to be further improved. A new version of the coupler is being designed at the HIM. Further development will mainly be focused on the heat input into the cryostat caused by the coupler. Also the coupler will have a modular design. This improves the accessibility and maintenance of the coupler. Various cryogenic and rf tests are foreseen, to provide a reliable, fail-safe coupler for the HELIAC. For an enhanced coupler test stand a movable reflector has been designed and built. With its movable semi-reflective element, it allows to operate the test stand in a resonance mode. In addition, the movable reflector can vary the coupling factor. This contribution discusses the recent coupler R&D for the HELIAC.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-MOP050
About •	paper received ※ 21 June 2019 paper accepted ※ 30 June 2019 issue date ※ 14 August 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP005	Cavity Designs for the CH3 to CH11 of the Superconducting Heavy Ion Accelerator HELIAC	396
SUSP009	use link to see paper's listing under its alternate paper code
	T. Conrad, M. Basten, M. Busch, H. Podlech, M. Schwarz IAP, Frankfurt am Main, Germany K. Aulenbacher, W.A. Barth, F.D. Dziuba, V. Gettmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu HIM, Mainz, Germany K. Aulenbacher KPH, Mainz, Germany W.A. Barth, M. Heilmann, A. Rubin, A. Schnase, S. Yaramyshev GSI, Darmstadt, Germany
	In collaboration of GSI, HIM and Goethe University Frankfurt new designs for the CH-DTL cavities of the proposed Helmholtz Linear Accelerator (HELIAC) are developed. The cw-mode operated linac with a final energy of 7.3 MeV/u is intended for various experiments, especially with heavy ions at energies near the coulomb barrier. Currently twelve superconducting CH-cavities are considered which will be split into four different cryostats. Each cavity will be equipped with dynamic bellow tuners. After successful beam tests with CH⁰ as well as last surface preparations and ongoing rf tests with CH1 and CH2, CH3 to CH11 will be designed. Based on the successful test results, individual optimizations are carried out on the cavity design. Attention was paid to reduce production costs, for example by keeping the cavity diameter in each cryostat constant despite varying particle velocities and gap numbers. In addition to reaching the resonance frequency of 216.816 MHz and the influence of the bellow tuners on the frequency, the mechanical stability of the bellow tuners, the thermal effects on the cavity and the measures to mitigate secondary electron emission are investigated.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-TUP005
About •	paper received ※ 19 June 2019 paper accepted ※ 30 June 2019 issue date ※ 14 August 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Considerations for Efficient RF Operation for the Advanced cw-Linac Demonstrator at GSI

267

C. Burandt, K. Aulenbacher, W.A. Barth, F.D. Dziuba, V. Gettmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, S. Yaramyshev
HIM, Mainz, Germany
K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, M. Heilmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, A. Schnase, S. Yaramyshev
GSI, Darmstadt, Germany
K. Aulenbacher, F.D. Dziuba, S. Lauber, J. List
IKP, Mainz, Germany
M. Basten, M. Busch, H. Podlech, M. Schwarz
IAP, Frankfurt am Main, Germany

The FAIR@GSI accelerator facility will require the GSI-UNILAC to provide short heavy ion pulses of highest intensity at low repetition rate for injection into the 18 Tm synchrotron SIS18. However, successful physics programs like SHE (Super Heavy Elements) rely on the UNILAC providing for heavy ion beams of high average current and high duty factor. In the next future, a dedicated super-conducting (sc) cw-Linac should therefore deliver cw beams to the experiments associated with those programs. As a first step towards this goal, beam tests with a single sc Cross-bar H-mode (CH) cavity were successfully conducted in 2017/2018. Within the scope of an Advanced Demonstrator project, current activities now aim at a beam test of a full cryomodule with three sc CH cavities and a sc rebuncher. Given a limited amount of rf power available per cavity and the necessity to accelerate different ion species with different mass-to-charge ratios, the loaded quality factor Q of the different resonators has to be chosen very carefully. This contribution discusses the simulations performed in this context.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-MOP081

About •

paper received ※ 21 June 2019 paper accepted ※ 29 June 2019 issue date ※ 14 August 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP004

Latest Cryogenic Test Results of the Superconducting β=0.069 CH-cavities for the HELIAC-project

392

M. Basten, M. Busch, T. Conrad, H. Podlech, M. Schwarz
IAP, Frankfurt am Main, Germany
K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, M. Heilmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, J. Salvatore, A. Schnase, S. Yaramyshev
GSI, Darmstadt, Germany
K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu
HIM, Mainz, Germany
K. Aulenbacher, S. Lauber
IKP, Mainz, Germany
F.D. Dziuba, J. List
KPH, Mainz, Germany

The upcoming FAIR (Facility for Antiproton and Ion Research) project at GSI will use the existing UNILAC (UNIversal Linear Accelerator) as an injector, reducing the beam time for the ambitious Super Heavy Element (SHE) program. To keep the UNILAC user program competitive a new superconducting (sc) continuous wave (cw) high intensity heavy ion LINAC should provide ion beams with max. duty factor above the coulomb barrier. The fundamental sc LINAC design comprises a low energy beam transport (LEBT)-section followed by a sc Drift Tube Linac (DTL) consisting of sc Crossbar-H-mode (CH) structures for acceleration up to 7.3 MeV/u. The latest milestones towards the new cw LINAC HELIAC (HELmholtz LInear ACcelerator) have been the successful tests and commissioning of the first demonstrator section with heavy ion beam in 2017 and 218 as well as the successful test under cryogenic conditions of the second CH-cavity in 2018. Now the third CH-cavity has been tested at cryogenic temperatures of 4 Kelvin at the Institute for Applied Physics (IAP) at Goethe University Frankfurt (GUF). The results of these measurements as well as the status of the HELIAC-project will be presented.

Poster TUP004 [0.958 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-TUP004

About •

paper received ※ 22 June 2019 paper accepted ※ 30 June 2019 issue date ※ 14 August 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP098

Preparation for the Advanced Demonstrator Testing at GSI

698

V. Gettmann, K. Aulenbacher, W.A. Barth, F.D. Dziuba, M. Heilmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, S. Yaramyshev
GSI, Darmstadt, Germany
K. Aulenbacher, W.A. Barth, F.D. Dziuba, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu
HIM, Mainz, Germany
K. Aulenbacher, F.D. Dziuba, S. Lauber
IKP, Mainz, Germany
M. Basten, H. Podlech, M. Schwarz
IAP, Frankfurt am Main, Germany

The superconducting (sc) heavy ion Helmholtz Linear Accelerator (HELIAC) is under development at GSI. As a first step, the cw-Linac demonstrator was the first part for the proposed cw-LINAC@GSI. A superconducting CH-cavity, embedded by two superconducting solenoids has been tested with beam in 2017/2018 successfully. The sc CH-structure, designed at Goethe-University of Frankfurt, is the key component and offers a variety of research and development. As a next step the first cryostat of the HELIAC, the so called Advanced Demonstrator will be tested in the same testing environment at GSI. Therefore, a bigger concrete Bunker as well as the connection to the cryo plant is under development. The cold string was assembled in a rehabilitated clean room at GSI. For future clean room assemblies a fully equipped clean room is under preparation at Helmholtz-Institut Mainz. The mechanical suspension, composed of hanging components on crossed steel ropes, is a reliable concept to prevent the displacement during cool down. The cryogenic systems as well as all other mechanical tasks were solved. These and the future Advanced Demonstrator preparation will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-TUP098

About •

paper received ※ 22 June 2019 paper accepted ※ 01 July 2019 issue date ※ 14 August 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THP101

Commissioning of a Cleanroom for SRF Activities at the Helmholtz Institute Mainz

1162

T. Kürzeder, K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, R.G. Heine, S. Lauber, J. List, M. Miski-Oglu
HIM, Mainz, Germany
K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, S. Lauber, J. List, M. Miski-Oglu, S. Yaramyshev
GSI, Darmstadt, Germany
K. Aulenbacher, F.D. Dziuba, S. Lauber
IKP, Mainz, Germany
J. Conrad
TU Darmstadt, Darmstadt, Germany
R.G. Heine, F. Hug, J. List, T. Stengler
KPH, Mainz, Germany

A newly built cleanroom is under commissioning at the Helmholtz-Institute Mainz (HIM). In its ISO-class 6 area vacuum components and cavities can be cleaned in different ultrasonic baths and in a dedicated conductance rinsing bath. In the ISO-class 4 area a large vacuum oven offers the possibility for comprehensive drying. A high pressure rinsing cabinet (HPR) has been installed between the two cleanroom areas to be loaded and unloaded from both sides. Complete cold-strings have to be mounted in the ISO-class 4 area and to be rolled out of the cleanroom on a rail system installed on the floor. All installations and tools have been integrated to treat and assemble superconducting 217 MHz multigap crossbar cavities for the Helmholtz Linear Accelerator (HELIAC), which is under development by HIM and GSI. Those crossbar cavities have a diameter of 650 mm and a weight of up to 100 kg. The cleanroom will be also used for the Mainz Energy-Recovering Superconducting Accelerator (MESA) project, processing the TESLA/XFEL type 9-cell cavities and other beamline components. This paper reports on the commissioning of the cleanroom and shows the features of the different installations.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-THP101

About •

paper received ※ 23 June 2019 paper accepted ※ 01 July 2019 issue date ※ 14 August 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THP103

Reconstruction of the Longitudinal Phase Space for the Superconducting CW HELIAC

1173

SUSP038

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

S. Lauber, K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, T. Kürzeder, J. List, M. Miski-Oglu
HIM, Mainz, Germany
K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, P. Forck, V. Gettmann, M. Heilmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, T. Sieber, S. Yaramyshev
GSI, Darmstadt, Germany
K. Aulenbacher, F.D. Dziuba, S. Lauber
IKP, Mainz, Germany
H. Podlech, M. Schwarz
IAP, Frankfurt am Main, Germany

The superconducting (SC) heavy ion HElmholtz LInear ACcelerator (HELIAC) is under development at GSI in Darmstadt in cooperation with Helmholtz Institute Mainz (HIM) and Goethe-University Frankfurt (GUF). A novel design is used for the accelerating cavities, namely SC continuous wave (CW) multigap Crossbar H-Mode cavities. For this a dedicated beam dynamics layout - the EQUidistant mUltigap Structure (EQUUS) - has been carried out a couple of years ago and is under further development. In December 2018 the GSI High Charge State Injector (HLI) delivered heavy ion beam to the already commissioned first of series superconducting RF cavity. Proper 6D-matching to the CH cavity demands sufficient beam characterisation. Slit-grid emittance measurements provided for the transverse phase space determination. By measuring the longitudinal projection of the bunch with a Feschenko Monitor (Beam Shape Monitor), the bunch profile was obtained. With a dedicated algorithm, the full longitudinal phase space at the HLI-exit could be reconstructed from a set of BSM measurements. The basic reconstruction method, all relevant BSM measurements and the resulting phase space reconstruction will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-THP103

About •

paper received ※ 19 June 2019 paper accepted ※ 29 June 2019 issue date ※ 14 August 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRCAA4

Progress in SRF CH-Cavities for the HELIAC CW Linac at GSI

1206

M. Miski-Oglu, K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, T. Kürzeder, S. Lauber, J. List, S. Yaramyshev
HIM, Mainz, Germany
K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, M. Heilmann, T. Kürzeder, S. Lauber, J. List, A. Rubin, A. Schnase, S. Yaramyshev
GSI, Darmstadt, Germany
K. Aulenbacher, F.D. Dziuba, J. List
KPH, Mainz, Germany
M. Basten, M. Busch, T. Conrad, H. Podlech, M. Schwarz
IAP, Frankfurt am Main, Germany
S. Lauber
IKP, Mainz, Germany

The machine beam commissioning is a major milestone of the R&D for the superconducting heavy ion continuous wave linear accelerator HELIAC of Helmholtz Institute Mainz (HIM) and GSI developed in collaboration with IAP Goethe-University Frankfurt. During successful beam commissioning of the superconducting 15-gap Crossbar H-mode cavity at GSI Helmholtzzentrum für Schwerionenforschung heavy ions up to the design beam energy have been accelerated. The design acceleration gain of 3.5 MeV has been reached with full transmission for heavy ion beams of up to 1.5 particle mueA. We present fabrication experience and results of off-line and on-line cavity performance. The next step is the procurement and commissioning of so called ’Advanced Demonstrator’ - the first of series cryomodule for the entire accelerator HELIAC. Results of further Demonstrator beam tests, as well as the status of the Advanced demonstrator project will be reported.

Slides FRCAA4 [9.864 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-FRCAA4

About •

paper received ※ 23 June 2019 paper accepted ※ 02 July 2019 issue date ※ 14 August 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP019

Surface Preparation and Optimization of SC CH Cavities

71

SUSP024

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

P. Müller, M. Basten, M. Busch, T. Conrad, H. Podlech
IAP, Frankfurt am Main, Germany
K. Aulenbacher, F.D. Dziuba, M. Miski-Oglu
HIM, Mainz, Germany
W.A. Barth
GSI, Darmstadt, Germany

The Institute of Applied Physics (IAP) introduced the superconducting multi-gap CH-structure, which is mainly designed for low beta hadron acceleration. In 2017, a 217 MHz sc CH-structure was successfully tested with beam at GSI and multiple CH-structures are currently under development for the GSI cw linac. RF performance of all sc cavities are limited by the surface properties of the used material. Therefore, sufficient surface preparation and optimization is necessary to achieve optimal performance. Presently as standard procedure BCP and HPR is used for CH-cavities. Several surface treatments will be applied to the very first CH-prototype, a 360 MHz, 19-cell cavity. Prior to the first treatment, the status of the cavity was examined, including leak tests and performance tests at 4 and 2 K. This paper presents the performance development of a sc CH cavity depending on different preparation methods.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-MOP019

About •

paper received ※ 23 June 2019 paper accepted ※ 05 July 2019 issue date ※ 14 August 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOP050

Modular Power Couplers for 217 MHz Superconducting CH-Cavities

168

SUSP034

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

J. List, K. Aulenbacher, W.A. Barth, C. Burandt, F.D. Dziuba, V. Gettmann, T. Kürzeder, S. Lauber, M. Miski-Oglu
HIM, Mainz, Germany
K. Aulenbacher, W.A. Barth, C. Burandt, V. Gettmann, M. Heilmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu, A. Schnase, S. Yaramyshev
GSI, Darmstadt, Germany
K. Aulenbacher, F.D. Dziuba, S. Lauber, J. List
IKP, Mainz, Germany
M. Basten, M. Busch, H. Podlech, M. Schwarz
IAP, Frankfurt am Main, Germany

The HELmholtz LInear ACcelerator (HELIAC) is being developed by a collaboration of HIM, GSI and the Goethe University of Frankfurt. It is a superconducting (sc), continuous wave (cw) heavy ion linac that comprises novel Crossbar H-mode (CH) cavities. In April 2017 and November/December 2018 the first sc CH-cavity of the linac was tested with beam. The first operations of the cavity showed, that the prototype of the rf power coupler needs to be further improved. A new version of the coupler is being designed at the HIM. Further development will mainly be focused on the heat input into the cryostat caused by the coupler. Also the coupler will have a modular design. This improves the accessibility and maintenance of the coupler. Various cryogenic and rf tests are foreseen, to provide a reliable, fail-safe coupler for the HELIAC. For an enhanced coupler test stand a movable reflector has been designed and built. With its movable semi-reflective element, it allows to operate the test stand in a resonance mode. In addition, the movable reflector can vary the coupling factor. This contribution discusses the recent coupler R&D for the HELIAC.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-MOP050

About •

paper received ※ 21 June 2019 paper accepted ※ 30 June 2019 issue date ※ 14 August 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUP005

Cavity Designs for the CH3 to CH11 of the Superconducting Heavy Ion Accelerator HELIAC

396

SUSP009

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

T. Conrad, M. Basten, M. Busch, H. Podlech, M. Schwarz
IAP, Frankfurt am Main, Germany
K. Aulenbacher, W.A. Barth, F.D. Dziuba, V. Gettmann, T. Kürzeder, S. Lauber, J. List, M. Miski-Oglu
HIM, Mainz, Germany
K. Aulenbacher
KPH, Mainz, Germany
W.A. Barth, M. Heilmann, A. Rubin, A. Schnase, S. Yaramyshev
GSI, Darmstadt, Germany

In collaboration of GSI, HIM and Goethe University Frankfurt new designs for the CH-DTL cavities of the proposed Helmholtz Linear Accelerator (HELIAC) are developed. The cw-mode operated linac with a final energy of 7.3 MeV/u is intended for various experiments, especially with heavy ions at energies near the coulomb barrier. Currently twelve superconducting CH-cavities are considered which will be split into four different cryostats. Each cavity will be equipped with dynamic bellow tuners. After successful beam tests with CH⁰ as well as last surface preparations and ongoing rf tests with CH1 and CH2, CH3 to CH11 will be designed. Based on the successful test results, individual optimizations are carried out on the cavity design. Attention was paid to reduce production costs, for example by keeping the cavity diameter in each cryostat constant despite varying particle velocities and gap numbers. In addition to reaching the resonance frequency of 216.816 MHz and the influence of the bellow tuners on the frequency, the mechanical stability of the bellow tuners, the thermal effects on the cavity and the measures to mitigate secondary electron emission are investigated.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2019-TUP005

About •

paper received ※ 19 June 2019 paper accepted ※ 30 June 2019 issue date ※ 14 August 2019

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)