LINAC2022 - List of Keywords (ECR)

Paper	Title	Other Keywords	Page
MOPOPA20	Q Drop Tendency of Half-Wave Resonator Cavity	cavity, radiation, vacuum, superconducting-cavity	118
	Y. Jung, H. Jang, H. Kim, H. Kim, J.W. Kim IBS, Daejeon, Republic of Korea S. Jeon Kyungpook National University, Daegu, Republic of Korea
	All HWRs (half-wave resonator superconducting cavities) have been fabricated and installed in the low energy section of the LINAC in IBS. All HWR cavities have been tested (vertical tests, VT) both at 4.2 K and 2.1 K cryogenic surroundings although operating temperature of HWRs is 2.1 K. Good cavities of high quality factors showed the Q drop tendency of 2.1 k were very similar to that of 4.2 K. However, in many cases, Q drop tendency of 2.1 K were not similar with 4.2 K, rather Q decreased more rapidly than 4.2 K which means the surface resistance of the cavity rapidly increased at 2 K surrounding. In this study, we will report that various Q results of HWRs and compare their Q drop tendency as a function of temperature, 2.1 K and 4.2 K.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-MOPOPA20
About •	Received ※ 23 August 2022 — Revised ※ 28 August 2022 — Accepted ※ 29 August 2022 — Issue date ※ 01 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOGE03	Design of a Linear Accelerator for Isotope Production	DTL, linac, rfq, target	142
	A. Pisent, C. Baltador, L. Bellan, M. Comunian, J. Esposito, L. Ferrari, A. Galatà, F. Grespan INFN/LNL, Legnaro (PD), Italy L. Celona INFN/LNS, Catania, Italy P. Mereu INFN-Torino, Torino, Italy
	The recent accelerator developments allow the design of very efficient linear accelerators for various applications. The possible use of concepts, components and developments well established or recently achieved in larger projects will be illustrated, with some examples related to isotope production for medical applications.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-MOPOGE03
About •	Received ※ 14 August 2022 — Revised ※ 16 August 2022 — Accepted ※ 30 August 2022 — Issue date ※ 05 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOGE23	Conservation of Quality Factor for Superconducting Cavity and Heartbeat under Relativistic Motion	cavity, acceleration, superconducting-cavity, resonance	204
	H. Kim IBS, Daejeon, Republic of Korea
	Funding: This research was supported by the Rare Isotope Science Project of Institute for Basic Science funded by Ministry of Science and National Research Foundation of Korea (NRF-2013M7A1A1075764). The conservation of quality factor under relativistic motion is applied to the superconducting cavity as well as the heartbeat of mammal. The quality factor of the superconducting cavity is conserved under relativistic motion. The frequency of the cavity decreases and the decay time increases as the velocity and acceleration are increased. The quality factor of the superconducting cavity is comparable with the total heartbeat of the mammal. The quality factor for the heartbeat of the mammal representing the total number of heartbeat is also conserved under relativistic motion. Therefore, the heart rate is inversely proportional to the life expectancy under relativistic motion.
	Poster MOPOGE23 [0.765 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-MOPOGE23
About •	Received ※ 25 July 2022 — Revised ※ 23 August 2022 — Accepted ※ 30 August 2022 — Issue date ※ 02 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPOGE24	Understanding Q Slope of Superconducting Cavity with Magnetic Defect and Field Emission	cavity, superconducting-cavity, radiation, cryomodule	208
	H. Kim, Y. Jung, H. Kim, J.W. Kim IBS, Daejeon, Republic of Korea S. Jeon Kyungpook National University, Daegu, Republic of Korea
	Funding: This research was supported by the RISP of ibs funded by the Ministry of Science and the National Research Foundation (NRF) of the Republic of Korea under Contract 2013M7A1A1075764. RF test for quarter-wave resonator (QWR) and half-wave resonator (HWR) superconducting cavities is performed at low temperature. The quality factors of the superconducting cavities are measured as a function of accelerating field. The magnetic heating effect for the quarter-wave resonator (QWR) is studied. For the half-wave resonator (HWR), the Q slope degradation is investigated with x-ray radiation and field emission.
	Slides MOPOGE24 [2.506 MB]
	Poster MOPOGE24 [1.174 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-MOPOGE24
About •	Received ※ 25 July 2022 — Revised ※ 18 August 2022 — Accepted ※ 23 August 2022 — Issue date ※ 12 October 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TH1AA02	Developments Towards FRIB Upgrade to 400 MeV/u for Heaviest Uranium Ions	cavity, background, cryomodule, linac	653
	K.E. McGee, K. Elliott, A. Ganshyn, W. Hartung, S.H. Kim, P.N. Ostroumov, J.T. Popielarski, L. Popielarski, A. Taylor, T. Xu FRIB, East Lansing, Michigan, USA G.V. Eremeev, F. Furuta, M. Martinello, O.S. Melnychuk, A.V. Netepenko Fermilab, Batavia, Illinois, USA B.M. Guilfoyle, M.P. Kelly, T. Reid ANL, Lemont, Illinois, USA
	High-Q₀ medium-velocity (beta opt = 0.6) 5-cell elliptical cavities for superconducting linacs are critical technology for advancing current and future projects such as the Proton Improvement Plan II linac and the proposed energy upgrade of Michigan State University’s Facility For Rare Isotope Beams linac, FRIB400. Previous work established the validity of the novel geometry of the FRIB400 prototype 644 MHz 5-cell elliptical β = 0.65 cavities for future high Q₀ development. In collaboration with FNAL, two leading-edge high-Q₀ recipes, N-doping and Mid-T baking, were tested in the 5-cell format. 2/0 N-doping + cold electropolishing was successful at achieving FRIB400 and PIP-II Q₀ requirements, achieving an unprecedented 3.8 x 10¹⁰ at 17.5 MV/m, satisfying the FRIB400 Q₀ requirements by 1.75 times in a low-gauss environment. Mid-T baking exceeded FRIB400 Q₀ requirements by 1.4 times, and benefitted from decreased residual resistance compared to the N-doped cavity test. Systematic ultrasonic thickness measurements in single-cell revealed bulk (150 microns) EP with the modified EP tool is consistent across the inner surfaces of the cavity walls.

	please see instructions how to view/control embeded videos
	Slides TH1AA02 [44.708 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-TH1AA02
About •	Received ※ 11 August 2022 — Revised ※ 22 August 2022 — Accepted ※ 23 September 2022 — Issue date ※ 14 October 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOPA04	Unfolding of Bremsstrahlung Photons Energy Spectra Emitted from Electron Cyclotron Resonance Ion Source	photon, plasma, electron, detector	750
	M.J. Kumwenda University of Dar es Salaam, Dar es Salaam, Tanzania J.-K. Ahn Korea University, Seoul, Republic of Korea
	The aim of present study is to determine end-point energies of the bremsstrahlung photons energy spectra emitted from 28-GHz ECRIS by using inverse-matrix unfold method. Azimuthal angular distribution of the bremsstrahlung photons from 28-GHz ECRIS were measured at Busan Center of KBSI. Gamma-ray detection system consists of three round type NaI(Tl) scintillation detectors positioned 62 cm radially from the beam axis and another detector placed at the extraction port for monitoring photon intensity along the beam axis. Bremsstrahlung photons energy spectra were measured at six azimuthal angles at RF power of 1 kW. Monte Carlo simulation based on Geant4 package was performed to take the geometrical acceptance and energy-dependent detection efficiency into account due to large non-uniformity in the material budget. We extracted true bremsstrahlung energy spectra using the inverse-matrix unfolding method. The end-point energies of the bremsstrahlung photons after application of deconvolution method were found to be 1.320±0.050 MeV, 1.530±0.070 MeV, 1.540±0.070 MeV, 1.690±0.030 MeV, 1.530±0.070 MeV and 1.690±0.030 MeV for 0°, 30°, 60°, 90°, 120° and 330°, respectively.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-THPOPA04
About •	Received ※ 23 August 2022 — Revised ※ 31 August 2022 — Accepted ※ 09 September 2022 — Issue date ※ 23 September 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPOPA20

Q Drop Tendency of Half-Wave Resonator Cavity

cavity, radiation, vacuum, superconducting-cavity

118

Y. Jung, H. Jang, H. Kim, H. Kim, J.W. Kim
IBS, Daejeon, Republic of Korea
S. Jeon
Kyungpook National University, Daegu, Republic of Korea

All HWRs (half-wave resonator superconducting cavities) have been fabricated and installed in the low energy section of the LINAC in IBS. All HWR cavities have been tested (vertical tests, VT) both at 4.2 K and 2.1 K cryogenic surroundings although operating temperature of HWRs is 2.1 K. Good cavities of high quality factors showed the Q drop tendency of 2.1 k were very similar to that of 4.2 K. However, in many cases, Q drop tendency of 2.1 K were not similar with 4.2 K, rather Q decreased more rapidly than 4.2 K which means the surface resistance of the cavity rapidly increased at 2 K surrounding. In this study, we will report that various Q results of HWRs and compare their Q drop tendency as a function of temperature, 2.1 K and 4.2 K.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-MOPOPA20

About •

Received ※ 23 August 2022 — Revised ※ 28 August 2022 — Accepted ※ 29 August 2022 — Issue date ※ 01 September 2022

Cite •

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

MOPOGE03

Design of a Linear Accelerator for Isotope Production

DTL, linac, rfq, target

142

A. Pisent, C. Baltador, L. Bellan, M. Comunian, J. Esposito, L. Ferrari, A. Galatà, F. Grespan
INFN/LNL, Legnaro (PD), Italy
L. Celona
INFN/LNS, Catania, Italy
P. Mereu
INFN-Torino, Torino, Italy

The recent accelerator developments allow the design of very efficient linear accelerators for various applications. The possible use of concepts, components and developments well established or recently achieved in larger projects will be illustrated, with some examples related to isotope production for medical applications.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-MOPOGE03

About •

Received ※ 14 August 2022 — Revised ※ 16 August 2022 — Accepted ※ 30 August 2022 — Issue date ※ 05 September 2022

Cite •

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

MOPOGE23

Conservation of Quality Factor for Superconducting Cavity and Heartbeat under Relativistic Motion

cavity, acceleration, superconducting-cavity, resonance

204

H. Kim
IBS, Daejeon, Republic of Korea

Funding: This research was supported by the Rare Isotope Science Project of Institute for Basic Science funded by Ministry of Science and National Research Foundation of Korea (NRF-2013M7A1A1075764).
The conservation of quality factor under relativistic motion is applied to the superconducting cavity as well as the heartbeat of mammal. The quality factor of the superconducting cavity is conserved under relativistic motion. The frequency of the cavity decreases and the decay time increases as the velocity and acceleration are increased. The quality factor of the superconducting cavity is comparable with the total heartbeat of the mammal. The quality factor for the heartbeat of the mammal representing the total number of heartbeat is also conserved under relativistic motion. Therefore, the heart rate is inversely proportional to the life expectancy under relativistic motion.

Poster MOPOGE23 [0.765 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-MOPOGE23

About •

Received ※ 25 July 2022 — Revised ※ 23 August 2022 — Accepted ※ 30 August 2022 — Issue date ※ 02 September 2022

Cite •

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

MOPOGE24

Understanding Q Slope of Superconducting Cavity with Magnetic Defect and Field Emission

cavity, superconducting-cavity, radiation, cryomodule

208

H. Kim, Y. Jung, H. Kim, J.W. Kim
IBS, Daejeon, Republic of Korea
S. Jeon
Kyungpook National University, Daegu, Republic of Korea

Funding: This research was supported by the RISP of ibs funded by the Ministry of Science and the National Research Foundation (NRF) of the Republic of Korea under Contract 2013M7A1A1075764.
RF test for quarter-wave resonator (QWR) and half-wave resonator (HWR) superconducting cavities is performed at low temperature. The quality factors of the superconducting cavities are measured as a function of accelerating field. The magnetic heating effect for the quarter-wave resonator (QWR) is studied. For the half-wave resonator (HWR), the Q slope degradation is investigated with x-ray radiation and field emission.

Slides MOPOGE24 [2.506 MB]

Poster MOPOGE24 [1.174 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-MOPOGE24

About •

Received ※ 25 July 2022 — Revised ※ 18 August 2022 — Accepted ※ 23 August 2022 — Issue date ※ 12 October 2022

Cite •

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

TH1AA02

Developments Towards FRIB Upgrade to 400 MeV/u for Heaviest Uranium Ions

cavity, background, cryomodule, linac

653

K.E. McGee, K. Elliott, A. Ganshyn, W. Hartung, S.H. Kim, P.N. Ostroumov, J.T. Popielarski, L. Popielarski, A. Taylor, T. Xu
FRIB, East Lansing, Michigan, USA
G.V. Eremeev, F. Furuta, M. Martinello, O.S. Melnychuk, A.V. Netepenko
Fermilab, Batavia, Illinois, USA
B.M. Guilfoyle, M.P. Kelly, T. Reid
ANL, Lemont, Illinois, USA

High-Q₀ medium-velocity (beta opt = 0.6) 5-cell elliptical cavities for superconducting linacs are critical technology for advancing current and future projects such as the Proton Improvement Plan II linac and the proposed energy upgrade of Michigan State University’s Facility For Rare Isotope Beams linac, FRIB400. Previous work established the validity of the novel geometry of the FRIB400 prototype 644 MHz 5-cell elliptical β = 0.65 cavities for future high Q₀ development. In collaboration with FNAL, two leading-edge high-Q₀ recipes, N-doping and Mid-T baking, were tested in the 5-cell format. 2/0 N-doping + cold electropolishing was successful at achieving FRIB400 and PIP-II Q₀ requirements, achieving an unprecedented 3.8 x 10¹⁰ at 17.5 MV/m, satisfying the FRIB400 Q₀ requirements by 1.75 times in a low-gauss environment. Mid-T baking exceeded FRIB400 Q₀ requirements by 1.4 times, and benefitted from decreased residual resistance compared to the N-doped cavity test. Systematic ultrasonic thickness measurements in single-cell revealed bulk (150 microns) EP with the modified EP tool is consistent across the inner surfaces of the cavity walls.

please see instructions how to view/control embeded videos

Slides TH1AA02 [44.708 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-TH1AA02

About •

Received ※ 11 August 2022 — Revised ※ 22 August 2022 — Accepted ※ 23 September 2022 — Issue date ※ 14 October 2022

Cite •

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

THPOPA04

Unfolding of Bremsstrahlung Photons Energy Spectra Emitted from Electron Cyclotron Resonance Ion Source

photon, plasma, electron, detector

750

M.J. Kumwenda
University of Dar es Salaam, Dar es Salaam, Tanzania
J.-K. Ahn
Korea University, Seoul, Republic of Korea

The aim of present study is to determine end-point energies of the bremsstrahlung photons energy spectra emitted from 28-GHz ECRIS by using inverse-matrix unfold method. Azimuthal angular distribution of the bremsstrahlung photons from 28-GHz ECRIS were measured at Busan Center of KBSI. Gamma-ray detection system consists of three round type NaI(Tl) scintillation detectors positioned 62 cm radially from the beam axis and another detector placed at the extraction port for monitoring photon intensity along the beam axis. Bremsstrahlung photons energy spectra were measured at six azimuthal angles at RF power of 1 kW. Monte Carlo simulation based on Geant4 package was performed to take the geometrical acceptance and energy-dependent detection efficiency into account due to large non-uniformity in the material budget. We extracted true bremsstrahlung energy spectra using the inverse-matrix unfolding method. The end-point energies of the bremsstrahlung photons after application of deconvolution method were found to be 1.320±0.050 MeV, 1.530±0.070 MeV, 1.540±0.070 MeV, 1.690±0.030 MeV, 1.530±0.070 MeV and 1.690±0.030 MeV for 0°, 30°, 60°, 90°, 120° and 330°, respectively.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2022-THPOPA04

About •

Received ※ 23 August 2022 — Revised ※ 31 August 2022 — Accepted ※ 09 September 2022 — Issue date ※ 23 September 2022

Cite •

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