IPAC2018 - List of Authors (Sajaev, V.)

Paper	Title	Page
TUPMF011	Calculation of Expected Orbit Motion Due to Girder Resonant Vibration at the APS Upgrade	1269
	V. Sajaev, Z. Liu, J. Nudell, C.A. Preissner ANL, Argonne, Illinois, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. The Advanced Photon Source (APS) is pursuing an upgrade to the storage ring that will provide electron beam with extremely low emittance. To allow users to take advantage of this small beam size, the beam orbit motion has to be kept stable to within a fraction of the beam size. To keep the beam orbit stable on a sub-micron level, one needs to carefully design magnet supports/girders so that the ground motion does not lead to excessive orbit motion due to resonant modes of magnet supports. In this paper, we will describe the process of calculating the expected orbit motion due to girder resonant vibration. First, we will present the simulation results for the girder resonant modes, then we will calculate the orbit amplification factors for the girder deformation modes, then calculate the expected orbit motion using measured ground motion spectrum. This process can be used to evaluate the design of the magnet supports.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF011
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TUPMF012	Determination of the Ground Motion Orbit Amplification Factors Dependence on the Frequency for the APS Upgrade Storage Ring	1272
	V. Sajaev, C.A. Preissner ANL, Argonne, Illinois, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. The Advanced Photon Source (APS) is pursuing an upgrade to the storage ring that will provide electron beam with extremely low emittance. To allow users to take advantage of this small beam size, the beam orbit motion has to be kept stable to within a fraction of the beam size, which translates to sub-micron orbit stability requirement. Ground motion provides significant contribution to the overall expected beam motion, especially at lower frequencies where the ground motion has larger amplitudes. At the same time, the lattice amplification factors reduce when the ground motion becomes coherent at low frequencies. In this paper, we will present simulation of the lattice amplification factor dependence on the ground motion coherence length and show results of the ground motion coherence measurements at APS. After that, we will determine the lattice amplification factors dependence on the ground motion frequency, that can be used to calculate the expected effect of the ground motion on the orbit stability.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF012
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TUPMF018	Simulation Studies of the Helical Superconducting Undulator Installed at APS	1290
	A. Xiao, V. Sajaev, Y.P. Sun ANL, Argonne, Illinois, USA
	A multi-year project at APS has resulted in construction of a helical superconducting undulator (HSCU) for installation in the ring. Before installation, simulation studies were done to ensure that APS performance will not be compromised. This paper describes the method used for calculating the HSCU's perturbation effects and the simulation results for both calculated and measured field map. Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF018
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TUPMK004	Using Decoherence to Prevent Damage to the Swap-Out Dump for the APS Upgrade	1494
	M. Borland, J.C. Dooling, R.R. Lindberg, V. Sajaev, A. Xiao ANL, Argonne, Illinois, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. The Advanced Photon Source (APS) is pursuing an upgrade of the storage ring to a hybrid seven-bend-achromat* design, which will operate in swap-out mode. The ultra-low emittance (about 30 pm in both planes) combined with the desire to provide high charge (15 nC) in individual bunches, entails very high energy density in the beam. Simple estimates, confirmed by simulation, indicate that interaction of such a bunch with the dump material will result in localized melting. Over time, it is possible that the beam would drill through the dump and vent the ring vacuum. This would seem to prevent extraction and dumping of bunches as part of swap out, and also suggests that transferring of bunches out of the ring carries significant risk. We devised an idea for using a pre-kicker to cause decoherence of the target bunch emittances, making it safe to extract. Simulations show that the concept works very well. *L. Farvacque et al., IPAC13, 79 (2013).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMK004
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THXGBD1	The Upgrade of the Advanced Photon Source	2872
	M. Borland, M. Abliz, N.D. Arnold, T.G. Berenc, J.M. Byrd, J.R. Calvey, J.A. Carter, J. Carwardine, H. Cease, Z.A. Conway, G. Decker, J.C. Dooling, L. Emery, J.D. Fuerst, K.C. Harkay, A.K. Jain, M.S. Jaski, P.S. Kallakuri, M.P. Kelly, S.H. Kim, R.M. Lill, R.R. Lindberg, J. Liu, Z. Liu, J. Nudell, C.A. Preissner, V. Sajaev, N. Sereno, X. Sun, Y.P. Sun, S. Veseli, J. Wang, U. Wienands, A. Xiao, C. Yao ANL, Argonne, Illinois, USA A. Blednykh BNL, Upton, Long Island, New York, USA
	After decades of successful operation as a 7-GeV synchrotron radiation source, the Advanced Photon Source is pursing a major upgrade that involves replacement of the storage ring with an ultra-low emittance multi-bend achromat design. Using a seven-bend hybrid multi-bend achromat with reverse bending magnets gives a natural emittance of 42 pm operated at 6 GeV. The x-ray brightness is predicted to increase by more than two orders of magnitude. Challenges are many, but appear manageable based on thorough simulation and in light of the experience gained from world-wide operation of 3^\text{rd}-generation light sources. The upgraded ring will operate in swap-out mode, which has allowed pushing the performance beyond the limits imposed by conventional operation.
	Slides THXGBD1 [14.684 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THXGBD1
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Paper

Title

Page

Calculation of Expected Orbit Motion Due to Girder Resonant Vibration at the APS Upgrade

1269

V. Sajaev, Z. Liu, J. Nudell, C.A. Preissner
ANL, Argonne, Illinois, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
The Advanced Photon Source (APS) is pursuing an upgrade to the storage ring that will provide electron beam with extremely low emittance. To allow users to take advantage of this small beam size, the beam orbit motion has to be kept stable to within a fraction of the beam size. To keep the beam orbit stable on a sub-micron level, one needs to carefully design magnet supports/girders so that the ground motion does not lead to excessive orbit motion due to resonant modes of magnet supports. In this paper, we will describe the process of calculating the expected orbit motion due to girder resonant vibration. First, we will present the simulation results for the girder resonant modes, then we will calculate the orbit amplification factors for the girder deformation modes, then calculate the expected orbit motion using measured ground motion spectrum. This process can be used to evaluate the design of the magnet supports.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF011

Export •

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

TUPMF012

Determination of the Ground Motion Orbit Amplification Factors Dependence on the Frequency for the APS Upgrade Storage Ring

1272

V. Sajaev, C.A. Preissner
ANL, Argonne, Illinois, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
The Advanced Photon Source (APS) is pursuing an upgrade to the storage ring that will provide electron beam with extremely low emittance. To allow users to take advantage of this small beam size, the beam orbit motion has to be kept stable to within a fraction of the beam size, which translates to sub-micron orbit stability requirement. Ground motion provides significant contribution to the overall expected beam motion, especially at lower frequencies where the ground motion has larger amplitudes. At the same time, the lattice amplification factors reduce when the ground motion becomes coherent at low frequencies. In this paper, we will present simulation of the lattice amplification factor dependence on the ground motion coherence length and show results of the ground motion coherence measurements at APS. After that, we will determine the lattice amplification factors dependence on the ground motion frequency, that can be used to calculate the expected effect of the ground motion on the orbit stability.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF012

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

TUPMF018

Simulation Studies of the Helical Superconducting Undulator Installed at APS

1290

A. Xiao, V. Sajaev, Y.P. Sun
ANL, Argonne, Illinois, USA

A multi-year project at APS has resulted in construction of a helical superconducting undulator (HSCU) for installation in the ring. Before installation, simulation studies were done to ensure that APS performance will not be compromised. This paper describes the method used for calculating the HSCU's perturbation effects and the simulation results for both calculated and measured field map.
Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMF018

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

TUPMK004

Using Decoherence to Prevent Damage to the Swap-Out Dump for the APS Upgrade

1494

M. Borland, J.C. Dooling, R.R. Lindberg, V. Sajaev, A. Xiao
ANL, Argonne, Illinois, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
The Advanced Photon Source (APS) is pursuing an upgrade of the storage ring to a hybrid seven-bend-achromat* design, which will operate in swap-out mode. The ultra-low emittance (about 30 pm in both planes) combined with the desire to provide high charge (15 nC) in individual bunches, entails very high energy density in the beam. Simple estimates, confirmed by simulation, indicate that interaction of such a bunch with the dump material will result in localized melting. Over time, it is possible that the beam would drill through the dump and vent the ring vacuum. This would seem to prevent extraction and dumping of bunches as part of swap out, and also suggests that transferring of bunches out of the ring carries significant risk. We devised an idea for using a pre-kicker to cause decoherence of the target bunch emittances, making it safe to extract. Simulations show that the concept works very well.
*L. Farvacque et al., IPAC13, 79 (2013).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPMK004

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

THXGBD1

The Upgrade of the Advanced Photon Source

2872

M. Borland, M. Abliz, N.D. Arnold, T.G. Berenc, J.M. Byrd, J.R. Calvey, J.A. Carter, J. Carwardine, H. Cease, Z.A. Conway, G. Decker, J.C. Dooling, L. Emery, J.D. Fuerst, K.C. Harkay, A.K. Jain, M.S. Jaski, P.S. Kallakuri, M.P. Kelly, S.H. Kim, R.M. Lill, R.R. Lindberg, J. Liu, Z. Liu, J. Nudell, C.A. Preissner, V. Sajaev, N. Sereno, X. Sun, Y.P. Sun, S. Veseli, J. Wang, U. Wienands, A. Xiao, C. Yao
ANL, Argonne, Illinois, USA
A. Blednykh
BNL, Upton, Long Island, New York, USA

After decades of successful operation as a 7-GeV synchrotron radiation source, the Advanced Photon Source is pursing a major upgrade that involves replacement of the storage ring with an ultra-low emittance multi-bend achromat design. Using a seven-bend hybrid multi-bend achromat with reverse bending magnets gives a natural emittance of 42 pm operated at 6 GeV. The x-ray brightness is predicted to increase by more than two orders of magnitude. Challenges are many, but appear manageable based on thorough simulation and in light of the experience gained from world-wide operation of 3^\text{rd}-generation light sources. The upgraded ring will operate in swap-out mode, which has allowed pushing the performance beyond the limits imposed by conventional operation.

Slides THXGBD1 [14.684 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THXGBD1

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