PAC2013 - List of Authors (Tsuchiya, K.)

Paper

Title

Page

Design of the Superconducting Magnet System for the SuperKEKB Interaction Region

759

N. Ohuchi, N. Higashi, H. Koiso, A. Morita, Y. Ohnishi, K. Oide, H. Sugimoto, M. Tawada, K. Tsuchiya, H. Yamaoka, Z.G. Zong
KEK, Ibaraki, Japan
M. Anerella, J. Escallier, A.K. Jain, A. Marone, B. Parker, P. Wanderer
BNL, Upton, Long Island, New York, USA

SuperKEKB are now being constructed with a target luminosity of 8×10³⁵ which is 40 times higher than KEKB. This luminosity can be achieved by the "Nano-Beam" scheme, in which both beams should be squeezed to about 50 nm at the beam interaction point, IP. The superconducting magnet system has been designed in order to attain high luminosity. The system consists of 8 superconducting quadrupoles, 4 superconducting solenoids and 43 superconducting correctors. The magnets are installed into two cryostats in the interaction region, IR. For each beam, the final focusing system consists of quadrupole-doublets with 8 superconducting quadrupoles. To reduce the beam emittance at the IP, the superconducting solenoids cancel the integral solenoid field of the particle detector, Belle II, on the beam lines. The corrector system is very complicated and the multi-layered coils are mainly assembled inside of the quadrupole bores. In the paper, we would like to describe the most updated design of the superconducting magnet system for the SuperKEKB IR.

Slides WEODA1 [2.097 MB]

THPBA04

Design and Construction of the Proto-type Quadrupole Magnets for the SuperKEKB Interaction Region

1232

N. Ohuchi, Y. Arimoto, H. Koiso, A. Morita, Y. Ohnishi, K. Oide, H. Sugimoto, M. Tawada, K. Tsuchiya, H. Yamaoka, Z.G. Zong
KEK, Ibaraki, Japan

In the SuperKEKB interaction region, IR, eight superconducting quadrupoles were designed as quadrupole-doublets for focusing beams. The superconducting quadrupoles, QC1P and QC1E, were designed to be placed at the closest positions on each beam line, positron and electron, respectively. QC1P has the smallest radius of 25 mm, and it is iron free magnet without iron yokes in order to make an optimized magnetic field profile along the beam line for the beam optics. The radius of QC1E is 33 mm and the magnet has iron yokes. The field gradients of QC1P and QC1E are designed as 76.4 T/m at 1800A and 91.6 T/m at 2000A, respectively. Two prototypes of QC1P and QC1E were constructed in KEK and the cold tests were performed. Two proto-types were excited over the design current without any quench. In this paper, we will report the detail designs of the magnets and field measurement results.

THPBA07

Superconducting Corrector IR Magnet Production for SuperKEKB

1241

B. Parker, M. Anerella, J. Escallier, A.K. Ghosh, H.M. Hocker, A.K. Jain, A. Marone, P. Wanderer
BNL, Upton, Long Island, New York, USA
Y. Arimoto, M. Iwasaki, N. Ohuchi, M. Tawada, K. Tsuchiya, H. Yamaoka, Z.G. Zong
KEK, Ibaraki, Japan

The SuperKEKB luminosity upgrade IR needs 43 different superconducting correction coils. There are dipole (b1), skew-dipole and skew-quad correctors, (a1, a2), for orbit and optics control and b3 and b4 correctors for acceptable circulating beam lifetime. Most coils are sandwiched inside the main IR quad apertures but a few are located on independent support tubes outside the quad collars or on interconnects between quads. Four complex external field cancel coils, b3-b6, are needed to buck non-linear fields outside the quads closest to the interaction point. In the IR crossing angle geometry the first quads have no magnetic yokes and the cancel coils’ end turn spacings must match the field falloff with increasing beam separation. SuperKEKB IR correctors have tight harmonic tolerances with allowed field deviation at the reference radius of a few gauss at each position along the coil. Also the cancel coils have a position dependent “twist” to generate the correct local amount of skew field for the SuperKEKB optics.

Paper	Title	Page
WEODA1	Design of the Superconducting Magnet System for the SuperKEKB Interaction Region	759
	N. Ohuchi, N. Higashi, H. Koiso, A. Morita, Y. Ohnishi, K. Oide, H. Sugimoto, M. Tawada, K. Tsuchiya, H. Yamaoka, Z.G. Zong KEK, Ibaraki, Japan M. Anerella, J. Escallier, A.K. Jain, A. Marone, B. Parker, P. Wanderer BNL, Upton, Long Island, New York, USA
	SuperKEKB are now being constructed with a target luminosity of 8×10³⁵ which is 40 times higher than KEKB. This luminosity can be achieved by the "Nano-Beam" scheme, in which both beams should be squeezed to about 50 nm at the beam interaction point, IP. The superconducting magnet system has been designed in order to attain high luminosity. The system consists of 8 superconducting quadrupoles, 4 superconducting solenoids and 43 superconducting correctors. The magnets are installed into two cryostats in the interaction region, IR. For each beam, the final focusing system consists of quadrupole-doublets with 8 superconducting quadrupoles. To reduce the beam emittance at the IP, the superconducting solenoids cancel the integral solenoid field of the particle detector, Belle II, on the beam lines. The corrector system is very complicated and the multi-layered coils are mainly assembled inside of the quadrupole bores. In the paper, we would like to describe the most updated design of the superconducting magnet system for the SuperKEKB IR.
	Slides WEODA1 [2.097 MB]

THPBA04	Design and Construction of the Proto-type Quadrupole Magnets for the SuperKEKB Interaction Region	1232
	N. Ohuchi, Y. Arimoto, H. Koiso, A. Morita, Y. Ohnishi, K. Oide, H. Sugimoto, M. Tawada, K. Tsuchiya, H. Yamaoka, Z.G. Zong KEK, Ibaraki, Japan
	In the SuperKEKB interaction region, IR, eight superconducting quadrupoles were designed as quadrupole-doublets for focusing beams. The superconducting quadrupoles, QC1P and QC1E, were designed to be placed at the closest positions on each beam line, positron and electron, respectively. QC1P has the smallest radius of 25 mm, and it is iron free magnet without iron yokes in order to make an optimized magnetic field profile along the beam line for the beam optics. The radius of QC1E is 33 mm and the magnet has iron yokes. The field gradients of QC1P and QC1E are designed as 76.4 T/m at 1800A and 91.6 T/m at 2000A, respectively. Two prototypes of QC1P and QC1E were constructed in KEK and the cold tests were performed. Two proto-types were excited over the design current without any quench. In this paper, we will report the detail designs of the magnets and field measurement results.

THPBA07	Superconducting Corrector IR Magnet Production for SuperKEKB	1241
	B. Parker, M. Anerella, J. Escallier, A.K. Ghosh, H.M. Hocker, A.K. Jain, A. Marone, P. Wanderer BNL, Upton, Long Island, New York, USA Y. Arimoto, M. Iwasaki, N. Ohuchi, M. Tawada, K. Tsuchiya, H. Yamaoka, Z.G. Zong KEK, Ibaraki, Japan
	The SuperKEKB luminosity upgrade IR needs 43 different superconducting correction coils. There are dipole (b1), skew-dipole and skew-quad correctors, (a1, a2), for orbit and optics control and b3 and b4 correctors for acceptable circulating beam lifetime. Most coils are sandwiched inside the main IR quad apertures but a few are located on independent support tubes outside the quad collars or on interconnects between quads. Four complex external field cancel coils, b3-b6, are needed to buck non-linear fields outside the quads closest to the interaction point. In the IR crossing angle geometry the first quads have no magnetic yokes and the cancel coils’ end turn spacings must match the field falloff with increasing beam separation. SuperKEKB IR correctors have tight harmonic tolerances with allowed field deviation at the reference radius of a few gauss at each position along the coil. Also the cancel coils have a position dependent “twist” to generate the correct local amount of skew field for the SuperKEKB optics.