IPAC2011 - List of Keywords (insertion-device)

Paper	Title	Other Keywords	Page
MOPO016	Commissioning Tune Feedback in the Taiwan Light Source	feedback, insertion, controls, undulator	517
	C.H. Kuo, J. Chen, Y.-S. Cheng, P.C. Chiu, K.T. Hsu, K.H. Hu, C.-Y. Liao, C.Y. Wu NSRRC, Hsinchu, Taiwan
	The tune control is important parameter in the insertion devices operation. There are many difference type insertion devices are disturbed in the storage ring of TLS. The traditional feed-forward control to correct orbit change and tune shift that isn’t enough when difference type insertion devices are operated with various condition. The tune feedback is used to solve the tune change problem. The stable tune measurement is necessary in the stable storage ring. There are various excited bunch train methods to get stable tune that will be also discussed in this report.

MOPO035	Stability of the Floor Slab at Diamond Light Source	site, insertion, storage-ring, target	562
	J. Kay, K.A.R. Baker, W.J. Hoffman Diamond, Oxfordshire, United Kingdom I.P.S. Martin JAI, Oxford, United Kingdom
	A Hydrostatic Leveling System (HLS) has been installed at Diamond Light Source. 8 sensors have been positioned along a 60 metre portion of the floor of the Storage Ring and the Experimental Hall, stretching out along a typical beamline route from Insertion Device to sample. Results since June 2008 are presented comparing actual performance with the original specification as well as identifying movements associated with environmental factors.

TUPS010	A Novel Approach in UHV Pumping of Accelerators: the NEXTorr® Pump	ion, vacuum, insertion, synchrotron	1536
	P. Manini, A. Bonucci, L. Caruso, A. Conte, F. Siviero, L. Viale SAES Getters S.p.A., Lainate, Italy
	In spite of the large dimensions of accelerators, like synchrotrons or colliders, the space available for mounting UHV pumps is getting smaller, due to design constraints, service equipments, conductances, magnets, various instrumentations. This poses challenges to traditional UHV pump designs which are called to provide more pumping performances in smaller spaces. A radically new approach is here presented which can mitigate this issue. In this approach Non Evaporable Getter (NEG) and ion pumping technologies are properly combined and integrated in one single device, called NEXTorr®, having a unique design. In this pump, the getter cartridge acts as the main UHV pumping element, leaving to a small sputter ion pump the ancillary task of removing noble gases and methane, not pumped by the NEG. This design allows achieving large pumping speed in a very small package as well as delivering interesting pumping synergies. Main features of this new pump, including pumping tests, and example of applications will be reported, with a special focus to accelerators and high energy physics systems. Its impact in the design of vacuum systems for accelerators will also be discussed.

WEPC068	Amplitude Dependent Betatron Oscillation Center Shift by Non-linearity and Beam Instability Interlock	betatron, insertion, simulation, sextupole	2178
	T. Nakamura, K. Kobayashi, J. Schimizu, T. Seike, K. Soutome, M. Takao JASRI/SPring-8, Hyogo-ken, Japan T. Hara RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
	The center of the betatron oscillation in storage rings shifts as the amplitude of the oscillation increases. This effect is produced by non-linear components like sextupole magnets with its first-order perturbation. This shift can be observed as the shift of the closed orbit with usual slow beam position monitor (BPM) for closed orbit measurement. At the SPring-8 storage ring, the insertion devices (IDs) have their dedicated BPMs for monitoring the beam axis in the IDs. If some amount of the shift of beam axis is observed, the beam is aborted to avoid the damage by the irradiation of the ring components by ID radiation. When a betatron oscillation is excited by a beam transverse instability, the beam axis also oscillates and might produce the damage. Though it is not easy to detect the oscillation amplitude in various bunch current and filling patterns like in SPring-8, the oscillation produces the shift of the center of the betatron oscillation and can be observed by the BPM of IDs, and the beam is aborted. Calculation, tracking simulation and observation will be reported.

WEPC072	Insertion Devices and Beam Dynamics in the PLS-II Storage Ring	wiggler, undulator, betatron, insertion	2187
	S. Chunjarean, S. Shin PAL, Pohang, Kyungbuk, Republic of Korea
	Effects of insertion devices like a superconducting multipole wiggler or an in-vacuum undulator on the beam dynamics of tghe upgraded Pohang Light Source (PLS-II) storage ring have been investigated. The narrow gap related to a short period length of the in-vacuum undulator or a transverse magnetic field roll off can impact the dynamic aperture or Touschek lifetime or injection efficiency. A three dimensional magnetic field model has been developed based on numerical data consisting of several coefficients in the Taylor expansion to accurately represent the actual field. In this paper, the magnetic field model has been produced with the differential algebraic code COSY INFINITY to formulate the Taylor transfer map for the wiggler and undulator. Frequency map analysis (FMA) and full 6D tracking has been performed to investigate resonances which may affect the particle stability and causing a reduction in injection efficiency.

WEPC157	Post-mortem Analysis at TLS	diagnostics, SRF, insertion, controls	2352
	Y.R. Pan, Y.-T. Chang, J. Chen, P.C. Chiu, K.T. Hsu, K.H. Hu, C.H. Kuo, C.-Y. Liao NSRRC, Hsinchu, Taiwan
	High availability and stability of the beam are important issues for the synchrotron light source. Analyzing of the post-mortem data is one of the most important approaches to reflect the machine error and identify the reason of beam trip. The post-mortem system has been developed at Taiwan Light Source (TLS) in 2008. This diagnostic data can provide useful information for troubleshooting and improve the beam reliability. The various diagnostic signals are read from hardware buffer and written to the file system by the post-mortem event trigger, which is generated by the signals of the beam trip detector, the superconducting RF system interlock and the superconducting insertion device interlock. In this report a processing is running to check whether a new trip event, promptly find out the unusual signals, and generate an analyzing result message. The detail will be discussed and summarized.

THPC152	Measurements of SOLEIL Insertion Devices using Pulsed Wire Method	insertion, undulator, wiggler, vacuum	3242
	M. Valléau, C. Benabderrahmane, M.-E. Couprie, O. Marcouillé, F. Marteau, J. Vétéran SOLEIL, Gif-sur-Yvette, France
	SOLEIL permanent magnets insertion devices are usually measured with a Hall probe in order to evaluate the electron angular deflexion, their deviation and the optical phase error, a figure of merit related to the quality of the insertion device radiation. A pulsed wire bench is developed at SOLEIL for reducing the measurement time of an undulator and for providing a measurement method without lateral access. A current pulse injected in a stretched wire inside the magnetic field area generates acoustic wave. The wire motion is detected by optical sensors whose signals are proportional to the local integral value. The signal-to-noise ratio of this method is often reduced due to several effects such as electronic noise, external and wire vibrations. However, following some hardware optimization it was possible to increase it up to almost 26 dB, making the method accurate and reproducible in order to realize efficient corrections. Measurements of first and second integral performed with Pulse wire, with Hall probe and with the electron beam are compared on three different types of insertions: an U18 in-vacuum cryogenic undulator, a HU60 APPLE-II undulator and a WSV50 in-vacuum wiggler.

THPC153	Recent Progress in Insertion Devices at the ESRF	undulator, multipole, insertion, quadrupole	3245
	J. Chavanne, G. Lebec, C. Penel, F. Revol ESRF, Grenoble, France
	Insertion Device activities at the ESRF are presently driven by the upgrade of more than ten beamlines. The concept of canted undulators is part of the requirements in a number of cases. Permanent Magnet Steerers (PMS) will be used to create canting angles of up to 5.4 mrad. The magnetic structure of PMS has been fully optimized to minimise space occupancy and magnetic perturbations induced on neighbouring undulators. The measured field quality of PMS recently constructed will be presented. The development of undulators dedicated to high photon energy is still being pursued. Following on from the successful operation since 2008 of a first Cryogenic Permanent Magnet Undulator (CPMU) installed in the ID6 beamline, a second device has been constructed. This 2 m long device has a period of 18 mm and will be operated at 145 K. The field measurements at cryogenic temperature are discussed hereafter.

THPC160	A Superconducting Switch for Insertion Devices with Variable Period Length	insertion, power-supply, undulator, wiggler	3266
	T. Holubek, T. Baumbach, S. Casalbuoni, S. Gerstl, A.W. Grau, M. Hagelstein, D. Saez de Jauregui Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany C. Boffo, W. Walter BNG, Würzburg, Germany
	Superconducting insertion devices (IDs) are very attractive for synchrotron light sources since they offer the possibility to enhance the tuning range and functionality significantly by period length switching. Period length switching can be realized by employing two or more individually powerable subsets of superconducting coils and by reversing the current in a part of the winding. So far, the first demonstration mock-up coil allowing period length tripling was fabricated and tested successfully. Here, we report on the feasibility of a superconducting switch operating at 4.2 K, immersed in a liquid Helium bath as well as under conduction cooled conditions.

THPC161	Possible Superconducting Insertion Devices with Period Length Doubling for Beamlines of Third Generation Light Sources	simulation, insertion, undulator, photon	3269
	D. Saez de Jauregui, T. Baumbach, S. Casalbuoni, S. Gerstl, A.W. Grau, M. Hagelstein, T. Holubek Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
	The tunability of an insertion device can be increased by period length switching, which in superconducting insertion devices (IDs) can be achieved by reversing the current in separately powered subsets of the superconducting windings. The feasibility of this concept has been experimentally proven. We study here different possibilities to tailor the needs of beamlines of third generation light sources: FEM simulations performed to compute the magnetic field on axis of such devices with different period lengths are reported together with the spectral simulations.

THPC162	Possible Application of NbTi Wire with Artificial Pinning Centres for Insertion Devices	undulator, brilliance, insertion, vacuum	3272
	T. Holubek, S. Casalbuoni, S. Gerstl, A.W. Grau, D. Saez de Jauregui Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany M. Klaeser, T. Schneider FZ Karlsruhe, Karlsruhe, Germany L. Motowidlo SupraMagnetics, Inc., Plantsville, USA
	Superconductive insertion devices (IDs) allow higher fields for a given gap and period length compared to the classical permanent magnet IDs. This technological concept permits to increase the brilliance and/or the photon energy. The working horse for superconducting magnets are multifilament NbTi wires, which are nowadays also used for superconducting insertion devices. Even higher magnetic fields can be reached by using a conductor with enhanced critical current density. Here, we propose a possible application for superconducting undulators, wound with NbTi wire with artificial pinning centres, developed by SupraMagnetics, Inc. We report the critical current characteristic, Jc(B), of short wire measured in a liquid helium bath, and the load-line of a racetrack coil, designed to simulate the field configuration on the conductor as in a superconducting undulator. Based on the measured load-line we report the simulations of the magnetic field on axis and of the spectrum in a third generation light source of a possible undulator wound with a wire having similar properties of the measured one.

THPC163	Local and Integral Field Measurement Setup for 2m Long Superconducting Undulator Coils	undulator, factory, synchrotron, insertion	3275
	A.W. Grau, T. Baumbach, S. Casalbuoni, S. Gerstl, M. Hagelstein, T. Holubek, D. Saez de Jauregui Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
	The performance of superconducting insertion devices depends strongly on their magnetic field quality. It is of fundamental importance to characterize the magnetic properties of insertion devices accurately before installation in synchrotron light sources. Thus a main part of the R&D program for superconducting insertion devices at the Karlsruhe Institute of Technology focuses on quality assessment. This contribution describes the instrumentation to perform magnetic measurements of the local field, of the field integrals and of the multipole components of superconducting undulator coils in a cold in vacuum (cryogen free) environment. It focuses on the outcome of the factory acceptance test together with results of first field measurements performed with mock-up coils.

THPC173	Modelization of Inhomogeneities in Permanent Magnet Blocks	undulator, permanent-magnet, insertion, simulation	3305
	V. Massana, J. Campmany, J. Marcos CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	Nowadays one of the main objectives for insertion devices manufacturers is to reduce the gap of undulators as much as possible while keeping the features of the generated magnetic field. Because of that, the effects of magnetic blocks’ inhomogeneities are playing an increasing role in the quality of the whole device. In this paper we present a modelization of the inhomogeneities of permanent magnet blocks used to build wigglers and undulators. The model is based in splitting individual magnet blocks in different parts which are considered magnetically homogeneous. The model takes into account the relative orientation of magnet blocks assembled into their holders as well as local magnetic properties. We have applied the model to fit magnetic field integrals measured with a fixed stretched wire bench and magnetization data obtained from Helmholtz coils measurements for both single blocks and groups of blocks mounted on a common holder. The results of the model fit with experimental data within an rms error of 6•10^-4 mT•m for individual blocks and 1.5•10^-4 mT•m in the case of magnet groups.

THPC175	Spectral Analysis of Arbitrary Strength Parameter for Various Insertion Devices	undulator, photon, wiggler, insertion	3311
	S.D. Chen, T.M. Uen NCTU, Hsinchu, Taiwan C.-S. Hwang NSRRC, Hsinchu, Taiwan
	An insertion device (ID) with medium strength parameter was hard to be defined as a wiggler or an undulator. Usually, this kind of ID was classified according to the user’s definition and to select the spectrum calculation formula of wiggler or undulator. The spectrum calculation formula for wiggler or undulator is quite difference and consequently obtain a big different flux density by using the same strength parameter. So, it is no way that the spectrum calculation of them is consistent. Therefore, a universal formula will be developed for the spectrum analysis for the different kinds of insertion devices that is with large different strength parameter (deflection parameter). Consequently, a modified spectrum calculation formula of ID with medium strength parameter was studied by reviewing the difference of existing spectrum formulas. The familiar formula of calculating undulator spectrum was modified and can be used on ID with arbitrary strength parameter. The algorithm of formula modification was described. Some relative issue, like the effect of phase error and energy spread, and taper undulator were also discussed herein.

THPC176	Progress in Insertion Devices for TPS in Phase I	undulator, insertion, photon, vacuum	3314
	C.H. Chang, C.-H. Chang, J.C. Huang, C.-S. Hwang, C.K. Yang NSRRC, Hsinchu, Taiwan
	Taiwan Photon Source (TPS) with beam energy 3 GeV and beam current 500 mA is a third-generation synchrotron radiation facility of medium energy. In the initial commissioning stage of TPS, the machine will be equipped with ten insertion devices (ID) and serve seven beamlines in phase I. Of these, three long straight sections configured as a double-minimum betay function lattice design with minimized beam influence of emittance are used for the installation of a pair of insertion devices in a straight section, two undulators of APPLE-II type and four in-vacuum undulators (IU), to produce great brilliance and coherent X-rays with great flux. The details of these insertion devices are explained herein.

Paper

Title

Other Keywords

Page

MOPO016

Commissioning Tune Feedback in the Taiwan Light Source

feedback, insertion, controls, undulator

517

C.H. Kuo, J. Chen, Y.-S. Cheng, P.C. Chiu, K.T. Hsu, K.H. Hu, C.-Y. Liao, C.Y. Wu
NSRRC, Hsinchu, Taiwan

The tune control is important parameter in the insertion devices operation. There are many difference type insertion devices are disturbed in the storage ring of TLS. The traditional feed-forward control to correct orbit change and tune shift that isn’t enough when difference type insertion devices are operated with various condition. The tune feedback is used to solve the tune change problem. The stable tune measurement is necessary in the stable storage ring. There are various excited bunch train methods to get stable tune that will be also discussed in this report.

MOPO035

Stability of the Floor Slab at Diamond Light Source

site, insertion, storage-ring, target

562

J. Kay, K.A.R. Baker, W.J. Hoffman
Diamond, Oxfordshire, United Kingdom
I.P.S. Martin
JAI, Oxford, United Kingdom

A Hydrostatic Leveling System (HLS) has been installed at Diamond Light Source. 8 sensors have been positioned along a 60 metre portion of the floor of the Storage Ring and the Experimental Hall, stretching out along a typical beamline route from Insertion Device to sample. Results since June 2008 are presented comparing actual performance with the original specification as well as identifying movements associated with environmental factors.

TUPS010

A Novel Approach in UHV Pumping of Accelerators: the NEXTorr® Pump

ion, vacuum, insertion, synchrotron

1536

P. Manini, A. Bonucci, L. Caruso, A. Conte, F. Siviero, L. Viale
SAES Getters S.p.A., Lainate, Italy

In spite of the large dimensions of accelerators, like synchrotrons or colliders, the space available for mounting UHV pumps is getting smaller, due to design constraints, service equipments, conductances, magnets, various instrumentations. This poses challenges to traditional UHV pump designs which are called to provide more pumping performances in smaller spaces. A radically new approach is here presented which can mitigate this issue. In this approach Non Evaporable Getter (NEG) and ion pumping technologies are properly combined and integrated in one single device, called NEXTorr®, having a unique design. In this pump, the getter cartridge acts as the main UHV pumping element, leaving to a small sputter ion pump the ancillary task of removing noble gases and methane, not pumped by the NEG. This design allows achieving large pumping speed in a very small package as well as delivering interesting pumping synergies. Main features of this new pump, including pumping tests, and example of applications will be reported, with a special focus to accelerators and high energy physics systems. Its impact in the design of vacuum systems for accelerators will also be discussed.

WEPC068

Amplitude Dependent Betatron Oscillation Center Shift by Non-linearity and Beam Instability Interlock

betatron, insertion, simulation, sextupole

2178

T. Nakamura, K. Kobayashi, J. Schimizu, T. Seike, K. Soutome, M. Takao
JASRI/SPring-8, Hyogo-ken, Japan
T. Hara
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan

The center of the betatron oscillation in storage rings shifts as the amplitude of the oscillation increases. This effect is produced by non-linear components like sextupole magnets with its first-order perturbation. This shift can be observed as the shift of the closed orbit with usual slow beam position monitor (BPM) for closed orbit measurement. At the SPring-8 storage ring, the insertion devices (IDs) have their dedicated BPMs for monitoring the beam axis in the IDs. If some amount of the shift of beam axis is observed, the beam is aborted to avoid the damage by the irradiation of the ring components by ID radiation. When a betatron oscillation is excited by a beam transverse instability, the beam axis also oscillates and might produce the damage. Though it is not easy to detect the oscillation amplitude in various bunch current and filling patterns like in SPring-8, the oscillation produces the shift of the center of the betatron oscillation and can be observed by the BPM of IDs, and the beam is aborted. Calculation, tracking simulation and observation will be reported.

WEPC072

Insertion Devices and Beam Dynamics in the PLS-II Storage Ring

wiggler, undulator, betatron, insertion

2187

S. Chunjarean, S. Shin
PAL, Pohang, Kyungbuk, Republic of Korea

Effects of insertion devices like a superconducting multipole wiggler or an in-vacuum undulator on the beam dynamics of tghe upgraded Pohang Light Source (PLS-II) storage ring have been investigated. The narrow gap related to a short period length of the in-vacuum undulator or a transverse magnetic field roll off can impact the dynamic aperture or Touschek lifetime or injection efficiency. A three dimensional magnetic field model has been developed based on numerical data consisting of several coefficients in the Taylor expansion to accurately represent the actual field. In this paper, the magnetic field model has been produced with the differential algebraic code COSY INFINITY to formulate the Taylor transfer map for the wiggler and undulator. Frequency map analysis (FMA) and full 6D tracking has been performed to investigate resonances which may affect the particle stability and causing a reduction in injection efficiency.

WEPC157

Post-mortem Analysis at TLS

diagnostics, SRF, insertion, controls

2352

Y.R. Pan, Y.-T. Chang, J. Chen, P.C. Chiu, K.T. Hsu, K.H. Hu, C.H. Kuo, C.-Y. Liao
NSRRC, Hsinchu, Taiwan

High availability and stability of the beam are important issues for the synchrotron light source. Analyzing of the post-mortem data is one of the most important approaches to reflect the machine error and identify the reason of beam trip. The post-mortem system has been developed at Taiwan Light Source (TLS) in 2008. This diagnostic data can provide useful information for troubleshooting and improve the beam reliability. The various diagnostic signals are read from hardware buffer and written to the file system by the post-mortem event trigger, which is generated by the signals of the beam trip detector, the superconducting RF system interlock and the superconducting insertion device interlock. In this report a processing is running to check whether a new trip event, promptly find out the unusual signals, and generate an analyzing result message. The detail will be discussed and summarized.

THPC152

Measurements of SOLEIL Insertion Devices using Pulsed Wire Method

insertion, undulator, wiggler, vacuum

3242

M. Valléau, C. Benabderrahmane, M.-E. Couprie, O. Marcouillé, F. Marteau, J. Vétéran
SOLEIL, Gif-sur-Yvette, France

SOLEIL permanent magnets insertion devices are usually measured with a Hall probe in order to evaluate the electron angular deflexion, their deviation and the optical phase error, a figure of merit related to the quality of the insertion device radiation. A pulsed wire bench is developed at SOLEIL for reducing the measurement time of an undulator and for providing a measurement method without lateral access. A current pulse injected in a stretched wire inside the magnetic field area generates acoustic wave. The wire motion is detected by optical sensors whose signals are proportional to the local integral value. The signal-to-noise ratio of this method is often reduced due to several effects such as electronic noise, external and wire vibrations. However, following some hardware optimization it was possible to increase it up to almost 26 dB, making the method accurate and reproducible in order to realize efficient corrections. Measurements of first and second integral performed with Pulse wire, with Hall probe and with the electron beam are compared on three different types of insertions: an U18 in-vacuum cryogenic undulator, a HU60 APPLE-II undulator and a WSV50 in-vacuum wiggler.

THPC153

Recent Progress in Insertion Devices at the ESRF

undulator, multipole, insertion, quadrupole

3245

J. Chavanne, G. Lebec, C. Penel, F. Revol
ESRF, Grenoble, France

Insertion Device activities at the ESRF are presently driven by the upgrade of more than ten beamlines. The concept of canted undulators is part of the requirements in a number of cases. Permanent Magnet Steerers (PMS) will be used to create canting angles of up to 5.4 mrad. The magnetic structure of PMS has been fully optimized to minimise space occupancy and magnetic perturbations induced on neighbouring undulators. The measured field quality of PMS recently constructed will be presented. The development of undulators dedicated to high photon energy is still being pursued. Following on from the successful operation since 2008 of a first Cryogenic Permanent Magnet Undulator (CPMU) installed in the ID6 beamline, a second device has been constructed. This 2 m long device has a period of 18 mm and will be operated at 145 K. The field measurements at cryogenic temperature are discussed hereafter.

THPC160

A Superconducting Switch for Insertion Devices with Variable Period Length

insertion, power-supply, undulator, wiggler

3266

T. Holubek, T. Baumbach, S. Casalbuoni, S. Gerstl, A.W. Grau, M. Hagelstein, D. Saez de Jauregui
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
C. Boffo, W. Walter
BNG, Würzburg, Germany

Superconducting insertion devices (IDs) are very attractive for synchrotron light sources since they offer the possibility to enhance the tuning range and functionality significantly by period length switching. Period length switching can be realized by employing two or more individually powerable subsets of superconducting coils and by reversing the current in a part of the winding. So far, the first demonstration mock-up coil allowing period length tripling was fabricated and tested successfully. Here, we report on the feasibility of a superconducting switch operating at 4.2 K, immersed in a liquid Helium bath as well as under conduction cooled conditions.

THPC161

Possible Superconducting Insertion Devices with Period Length Doubling for Beamlines of Third Generation Light Sources

simulation, insertion, undulator, photon

3269

D. Saez de Jauregui, T. Baumbach, S. Casalbuoni, S. Gerstl, A.W. Grau, M. Hagelstein, T. Holubek
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany

The tunability of an insertion device can be increased by period length switching, which in superconducting insertion devices (IDs) can be achieved by reversing the current in separately powered subsets of the superconducting windings. The feasibility of this concept has been experimentally proven. We study here different possibilities to tailor the needs of beamlines of third generation light sources: FEM simulations performed to compute the magnetic field on axis of such devices with different period lengths are reported together with the spectral simulations.

THPC162

Possible Application of NbTi Wire with Artificial Pinning Centres for Insertion Devices

undulator, brilliance, insertion, vacuum

3272

T. Holubek, S. Casalbuoni, S. Gerstl, A.W. Grau, D. Saez de Jauregui
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
M. Klaeser, T. Schneider
FZ Karlsruhe, Karlsruhe, Germany
L. Motowidlo
SupraMagnetics, Inc., Plantsville, USA

Superconductive insertion devices (IDs) allow higher fields for a given gap and period length compared to the classical permanent magnet IDs. This technological concept permits to increase the brilliance and/or the photon energy. The working horse for superconducting magnets are multifilament NbTi wires, which are nowadays also used for superconducting insertion devices. Even higher magnetic fields can be reached by using a conductor with enhanced critical current density. Here, we propose a possible application for superconducting undulators, wound with NbTi wire with artificial pinning centres, developed by SupraMagnetics, Inc. We report the critical current characteristic, Jc(B), of short wire measured in a liquid helium bath, and the load-line of a racetrack coil, designed to simulate the field configuration on the conductor as in a superconducting undulator. Based on the measured load-line we report the simulations of the magnetic field on axis and of the spectrum in a third generation light source of a possible undulator wound with a wire having similar properties of the measured one.

THPC163

Local and Integral Field Measurement Setup for 2m Long Superconducting Undulator Coils

undulator, factory, synchrotron, insertion

3275

A.W. Grau, T. Baumbach, S. Casalbuoni, S. Gerstl, M. Hagelstein, T. Holubek, D. Saez de Jauregui
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany

The performance of superconducting insertion devices depends strongly on their magnetic field quality. It is of fundamental importance to characterize the magnetic properties of insertion devices accurately before installation in synchrotron light sources. Thus a main part of the R&D program for superconducting insertion devices at the Karlsruhe Institute of Technology focuses on quality assessment. This contribution describes the instrumentation to perform magnetic measurements of the local field, of the field integrals and of the multipole components of superconducting undulator coils in a cold in vacuum (cryogen free) environment. It focuses on the outcome of the factory acceptance test together with results of first field measurements performed with mock-up coils.

THPC173

Modelization of Inhomogeneities in Permanent Magnet Blocks

undulator, permanent-magnet, insertion, simulation

3305

V. Massana, J. Campmany, J. Marcos
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

Nowadays one of the main objectives for insertion devices manufacturers is to reduce the gap of undulators as much as possible while keeping the features of the generated magnetic field. Because of that, the effects of magnetic blocks’ inhomogeneities are playing an increasing role in the quality of the whole device. In this paper we present a modelization of the inhomogeneities of permanent magnet blocks used to build wigglers and undulators. The model is based in splitting individual magnet blocks in different parts which are considered magnetically homogeneous. The model takes into account the relative orientation of magnet blocks assembled into their holders as well as local magnetic properties. We have applied the model to fit magnetic field integrals measured with a fixed stretched wire bench and magnetization data obtained from Helmholtz coils measurements for both single blocks and groups of blocks mounted on a common holder. The results of the model fit with experimental data within an rms error of 6•10^-4 mT•m for individual blocks and 1.5•10^-4 mT•m in the case of magnet groups.

THPC175

Spectral Analysis of Arbitrary Strength Parameter for Various Insertion Devices

undulator, photon, wiggler, insertion

3311

S.D. Chen, T.M. Uen
NCTU, Hsinchu, Taiwan
C.-S. Hwang
NSRRC, Hsinchu, Taiwan

An insertion device (ID) with medium strength parameter was hard to be defined as a wiggler or an undulator. Usually, this kind of ID was classified according to the user’s definition and to select the spectrum calculation formula of wiggler or undulator. The spectrum calculation formula for wiggler or undulator is quite difference and consequently obtain a big different flux density by using the same strength parameter. So, it is no way that the spectrum calculation of them is consistent. Therefore, a universal formula will be developed for the spectrum analysis for the different kinds of insertion devices that is with large different strength parameter (deflection parameter). Consequently, a modified spectrum calculation formula of ID with medium strength parameter was studied by reviewing the difference of existing spectrum formulas. The familiar formula of calculating undulator spectrum was modified and can be used on ID with arbitrary strength parameter. The algorithm of formula modification was described. Some relative issue, like the effect of phase error and energy spread, and taper undulator were also discussed herein.

THPC176

Progress in Insertion Devices for TPS in Phase I

undulator, insertion, photon, vacuum

3314

C.H. Chang, C.-H. Chang, J.C. Huang, C.-S. Hwang, C.K. Yang
NSRRC, Hsinchu, Taiwan

Taiwan Photon Source (TPS) with beam energy 3 GeV and beam current 500 mA is a third-generation synchrotron radiation facility of medium energy. In the initial commissioning stage of TPS, the machine will be equipped with ten insertion devices (ID) and serve seven beamlines in phase I. Of these, three long straight sections configured as a double-minimum betay function lattice design with minimized beam influence of emittance are used for the installation of a pair of insertion devices in a straight section, two undulators of APPLE-II type and four in-vacuum undulators (IU), to produce great brilliance and coherent X-rays with great flux. The details of these insertion devices are explained herein.