2011 Particle Accelerator Conference - Classification: Light Sources and FELs / Tech 12: Injection, Extraction, and Transport

Paper	Title	Page
THP134	Lifetime Measurement with Pseudo Moveable Septum in NSLS X-ray Ring	2375
	G.M. Wang, J. Choi, R. Heese, S.L. Kramer, T.V. Shaftan, X. Yang BNL, Upton, Long Island, New York, USA
	Funding: Work supported by U.S. DOE, Contract No.DE-AC02-98CH10886 The National Synchrotron Light Source II (NSLS-II) is a state of the art 3 GeV third generation light source currently under construction at Brookhaven National Laboratory and starts to commission in 2014. The beam injection works with two septa and four fast kicker magnets in an injection section. To improve the injection stability and reproducibility, we plan to implement a slow local bump on top of the fast bump so that the fast kicker strength is reduced. This bump works as a pseudo movable septum. We can also use this ‘movable’ septum to measure the storage ring beam partial lifetime resulting from the septum edge and possibly increasing the lifetime by moving the stored beam orbit away from the edge. We demonstrate the feasibility of this idea, by implementing DC bump in NSLS X-ray ring. We report the results of beam lifetime measurements as a function of the amplitude of this bumped orbit relative to the septum and the idea of a slow bump that could reduce the fast bump magnet strengths.

THP135	Implementation of a DC Bump at the Storage Ring Injection Straight Section	2378
	G.M. Wang, R.P. Fliller, W. Guo, R. Heese, S.L. Kramer, B. Parker, T.V. Shaftan, C.J. Spataro, F.J. Willeke, L.-H. Yu BNL, Upton, Long Island, New York, USA
	Funding: Work supported by U.S. DOE, Contract No.DE-AC02-98CH10886 The NSLS II beam injection works with two septa and four fast kicker magnets. The kicker power supplies each produce a two revolution periods pulsed field, 5.2μs half sine waveform, using ~5kV drive voltage. The corresponding close orbit bump amplitude is ~15mm. It is desired that the bump they produce is transparent to the users for top-off injection. However, high voltage and short pulse power supplies have challenges to maintain pulse-to-pulse stability and magnet-to-magnet reproducibility. To minimize these issues, we propose to implement a DC local bump on top of the fast bump to reduce the fast kicker strength by a factor of 2/3. This bump uses two ring corrector magnets plus one additional magnet at the septum to create a bump. Additionally, these magnets could provide a DC bump, which would simulate the effects of a movable septum on the store beam lifetime. This paper presents the detail design of this DC injection bump and related beam dynamics.

THP213	Traveling Wave Electron Linac for Synchrotron Injector	2519
	S.V. Kutsaev, K.I. Nikolskiy, N.P. Sobenin MEPhI, Moscow, Russia
	In this paper the project design of a travelling wave electron linac used as an injector to synchrotron in Lebedev Physical Institute of the Russian Academy of Sciences (LPI RAS) is presented. The injected beam to the synchrotron should have very small emittance and energy spectrum. Thus, the buncher design is an essential question in this problem. One of the best output beam parameters can be achieved by using a waveguide buncher with the non-uniform parameters. The proposals of optimal buncher design and beam dynamics calculation results are presented.

THP214	Pulsed Multipole Injection for the MAX IV Storage Rings	2522
	S.C. Leemann MAX-lab, Lund, Sweden
	The MAX IV facility presently under construction will include two storage rings for the production of synchrotron radiation. The 3 GeV ring will house insertion devices for the production for x-rays while the 1.5 GeV ring will serve UV and IR users. Both rings will be operated at a constant 500 mA of stored current with top-up shots supplied by the 3.5 GeV MAX IV linac acting as a full-energy injector. So far, injection into both storage rings has been designed using a conventional approach: a closed four-kicker injection bump brings the stored beam to the septum blade where the injected bunches are captured in a single turn. Recently, studies have been carried out to investigate the feasibility of using a pulsed multipole for injection into the storage rings. Pulsed multipole injection does not require an injection bump and has the potential to make top-up injection transparent to users. This paper reports on these studies and summarizes requirements for the pulsed sextupole magnet to be installed for injection into the MAX IV storage rings.

THP215	Performance of the Diagnostics for NSLS-II Linac Commissioning	2525
	R.P. Fliller, R. Heese, H.-C. Hseuh, M.P. Johanson, B.N. Kosciuk, D. Padrazo, I. Pinayev, J. Rose, T.V. Shaftan, O. Singh, G.M. Wang BNL, Upton, Long Island, New York, USA
	Funding: This manuscript has been authored by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The National Synchrotron Light Source II (NSLS-II) is a state of the art 3 GeV third generation light source currently under construction at Brookhaven National Laboratory. The NSLS-II injection system consists of a 200 MeV linac and a 3 GeV booster synchrotron and associated transfer lines. The transfer lines not only provide a means to delivering the beam from one machine to another, they also provide a suite of diagnostics and utilities to measure the properties of the beam to be delivered. In this paper we discuss the suite of diagnostics that will be used to commission the NSLS-II linac and measure the beam properties. The linac to booster transfer line can measure the linac emittance with a three screens measurement or a quadrupole scan. Energy and energy spread are measured in a dispersive section. Total charge and charge uniformity are measured with wall current monitors in the linac and transformers in the transfer line. We show that the performance of the transfer line will be sufficient to ensure the linac meets its specifications and provides a means of trouble shooting and studying the linac in future operation.

THP216	Progress with NSLS-II Injection Straight Section Design	2528
	T.V. Shaftan, A. Blednykh, W.R. Casey, L.R. Dalesio, R. Faussete, M.J. Ferreira, R.P. Fliller, G. Ganetis, R. Heese, H.-C. Hseuh, P.K. Job, E.D. Johnson, B.N. Kosciuk, S. Kowalski, S.L. Kramer, D. Padrazo, B. Parker, I. Pinayev, S.K. Sharma, O. Singh, C.J. Spataro, G.M. Wang, F.J. Willeke BNL, Upton, Long Island, New York, USA
	Funding: This work is supported by U.S. DOE, Contract No.DE-AC02-98CH10886 NSLS-II injection straight section consists of the pulsed and DC/Slow bumps, septa system, beam trajectory correction and diagnostics systems. In this paper we discuss overall injection straight layout, preliminary element designs, specifications for the pulsed and DC magnets and their power supplies, vacuum devices and chambers and diagnostics devices.

THP217	Frequent Fill Top-Off Injection at SPEAR3	2531
	J.J. Sebek, S. Allison, S.M. Gierman, X. Huang, J.A. Safranek, J.F. Schmerge, K. Tian, C. Wermelskirchen SLAC, Menlo Park, California, USA
	Funding: Work supported by the U.S. Department of Energy under contract number DE-AC02-76-SF00515 SPEAR3 beam is now delivered to users in a "frequent fill" mode in which beam is injected into the storage ring, with beam-line shutters open, on a periodic schedule so that the beam current is kept constant to within 1% of its average value. This goal was achieved with the constraints of having the SPEAR3 injector run at very high reliability and ensuring that there would be no challenges to the beam containment system in this operational mode. This paper presents the accelerator development, the hardware changes, and the software developed to implement this operational mode.

Paper

Title

Page

Lifetime Measurement with Pseudo Moveable Septum in NSLS X-ray Ring

2375

G.M. Wang, J. Choi, R. Heese, S.L. Kramer, T.V. Shaftan, X. Yang
BNL, Upton, Long Island, New York, USA

Funding: Work supported by U.S. DOE, Contract No.DE-AC02-98CH10886
The National Synchrotron Light Source II (NSLS-II) is a state of the art 3 GeV third generation light source currently under construction at Brookhaven National Laboratory and starts to commission in 2014. The beam injection works with two septa and four fast kicker magnets in an injection section. To improve the injection stability and reproducibility, we plan to implement a slow local bump on top of the fast bump so that the fast kicker strength is reduced. This bump works as a pseudo movable septum. We can also use this ‘movable’ septum to measure the storage ring beam partial lifetime resulting from the septum edge and possibly increasing the lifetime by moving the stored beam orbit away from the edge. We demonstrate the feasibility of this idea, by implementing DC bump in NSLS X-ray ring. We report the results of beam lifetime measurements as a function of the amplitude of this bumped orbit relative to the septum and the idea of a slow bump that could reduce the fast bump magnet strengths.

THP135

Implementation of a DC Bump at the Storage Ring Injection Straight Section

2378

G.M. Wang, R.P. Fliller, W. Guo, R. Heese, S.L. Kramer, B. Parker, T.V. Shaftan, C.J. Spataro, F.J. Willeke, L.-H. Yu
BNL, Upton, Long Island, New York, USA

Funding: Work supported by U.S. DOE, Contract No.DE-AC02-98CH10886
The NSLS II beam injection works with two septa and four fast kicker magnets. The kicker power supplies each produce a two revolution periods pulsed field, 5.2μs half sine waveform, using ~5kV drive voltage. The corresponding close orbit bump amplitude is ~15mm. It is desired that the bump they produce is transparent to the users for top-off injection. However, high voltage and short pulse power supplies have challenges to maintain pulse-to-pulse stability and magnet-to-magnet reproducibility. To minimize these issues, we propose to implement a DC local bump on top of the fast bump to reduce the fast kicker strength by a factor of 2/3. This bump uses two ring corrector magnets plus one additional magnet at the septum to create a bump. Additionally, these magnets could provide a DC bump, which would simulate the effects of a movable septum on the store beam lifetime. This paper presents the detail design of this DC injection bump and related beam dynamics.

THP213

Traveling Wave Electron Linac for Synchrotron Injector

2519

S.V. Kutsaev, K.I. Nikolskiy, N.P. Sobenin
MEPhI, Moscow, Russia

In this paper the project design of a travelling wave electron linac used as an injector to synchrotron in Lebedev Physical Institute of the Russian Academy of Sciences (LPI RAS) is presented. The injected beam to the synchrotron should have very small emittance and energy spectrum. Thus, the buncher design is an essential question in this problem. One of the best output beam parameters can be achieved by using a waveguide buncher with the non-uniform parameters. The proposals of optimal buncher design and beam dynamics calculation results are presented.

THP214

Pulsed Multipole Injection for the MAX IV Storage Rings

2522

S.C. Leemann
MAX-lab, Lund, Sweden

The MAX IV facility presently under construction will include two storage rings for the production of synchrotron radiation. The 3 GeV ring will house insertion devices for the production for x-rays while the 1.5 GeV ring will serve UV and IR users. Both rings will be operated at a constant 500 mA of stored current with top-up shots supplied by the 3.5 GeV MAX IV linac acting as a full-energy injector. So far, injection into both storage rings has been designed using a conventional approach: a closed four-kicker injection bump brings the stored beam to the septum blade where the injected bunches are captured in a single turn. Recently, studies have been carried out to investigate the feasibility of using a pulsed multipole for injection into the storage rings. Pulsed multipole injection does not require an injection bump and has the potential to make top-up injection transparent to users. This paper reports on these studies and summarizes requirements for the pulsed sextupole magnet to be installed for injection into the MAX IV storage rings.

THP215

Performance of the Diagnostics for NSLS-II Linac Commissioning

2525

R.P. Fliller, R. Heese, H.-C. Hseuh, M.P. Johanson, B.N. Kosciuk, D. Padrazo, I. Pinayev, J. Rose, T.V. Shaftan, O. Singh, G.M. Wang
BNL, Upton, Long Island, New York, USA

Funding: This manuscript has been authored by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The National Synchrotron Light Source II (NSLS-II) is a state of the art 3 GeV third generation light source currently under construction at Brookhaven National Laboratory. The NSLS-II injection system consists of a 200 MeV linac and a 3 GeV booster synchrotron and associated transfer lines. The transfer lines not only provide a means to delivering the beam from one machine to another, they also provide a suite of diagnostics and utilities to measure the properties of the beam to be delivered. In this paper we discuss the suite of diagnostics that will be used to commission the NSLS-II linac and measure the beam properties. The linac to booster transfer line can measure the linac emittance with a three screens measurement or a quadrupole scan. Energy and energy spread are measured in a dispersive section. Total charge and charge uniformity are measured with wall current monitors in the linac and transformers in the transfer line. We show that the performance of the transfer line will be sufficient to ensure the linac meets its specifications and provides a means of trouble shooting and studying the linac in future operation.

THP216

Progress with NSLS-II Injection Straight Section Design

2528

T.V. Shaftan, A. Blednykh, W.R. Casey, L.R. Dalesio, R. Faussete, M.J. Ferreira, R.P. Fliller, G. Ganetis, R. Heese, H.-C. Hseuh, P.K. Job, E.D. Johnson, B.N. Kosciuk, S. Kowalski, S.L. Kramer, D. Padrazo, B. Parker, I. Pinayev, S.K. Sharma, O. Singh, C.J. Spataro, G.M. Wang, F.J. Willeke
BNL, Upton, Long Island, New York, USA

Funding: This work is supported by U.S. DOE, Contract No.DE-AC02-98CH10886
NSLS-II injection straight section consists of the pulsed and DC/Slow bumps, septa system, beam trajectory correction and diagnostics systems. In this paper we discuss overall injection straight layout, preliminary element designs, specifications for the pulsed and DC magnets and their power supplies, vacuum devices and chambers and diagnostics devices.

THP217

Frequent Fill Top-Off Injection at SPEAR3

2531

J.J. Sebek, S. Allison, S.M. Gierman, X. Huang, J.A. Safranek, J.F. Schmerge, K. Tian, C. Wermelskirchen
SLAC, Menlo Park, California, USA

Funding: Work supported by the U.S. Department of Energy under contract number DE-AC02-76-SF00515
SPEAR3 beam is now delivered to users in a "frequent fill" mode in which beam is injected into the storage ring, with beam-line shutters open, on a periodic schedule so that the beam current is kept constant to within 1% of its average value. This goal was achieved with the constraints of having the SPEAR3 injector run at very high reliability and ensuring that there would be no challenges to the beam containment system in this operational mode. This paper presents the accelerator development, the hardware changes, and the software developed to implement this operational mode.