IPAC2018 - List of Authors (Steier, C.)

Paper	Title	Page
WEXGBE2	Compensation of Insertion Device Induced Emittance Variations in Ultralow Emittance Storage Rings	1751
	F. Sannibale, S.C. Leemann, H. Nishimura, D. Robin, C. Steier, C. Sun, M. Venturini LBNL, Berkeley, California, USA
	Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231. With the advent of multi-bend achromat lattices, extremely low emittances are to become the norm in storage ring-based X-ray photon sources. In these lattices, the ratio of beam energy lost to radiation in the Insertion Devices (IDs) to the overall beam energy loss is relatively larger than in 3rd generation light sources. As a result, these machines are more sensitive to the energy loss variations occurring as the users operate variable-gap IDs and to the concurrent variations in radiation damping time, equilibrium emittance, and ultimately transverse properties of the beam. With possibly tens of variable gap IDs continuously and independently varying their gaps to meet the experiment needs, the resulting variation in emittance and beam sizes can be significant and can jeopardize the experimental performance in some of the beamlines. In this paper we describe and discuss possible methods for compensating such emittance variations and maintaining constant transverse beam properties for the experiments.
	Slides WEXGBE2 [4.543 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEXGBE2
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THPAK037	Beam-Loading Transients and Bunch Shape in the Operation of Passive Harmonic Cavities in the ALS-U	3298
SUSPF073	use link to see paper's listing under its alternate paper code
	Z. Pan, S. De Santis, C. Steier, C. Sun, M. Venturini LBNL, Berkeley, California, USA T. Hellert DESY, Hamburg, Germany C.-X. Tang TUB, Beijing, People's Republic of China
	The ALS-U is a major upgrade of the LBNL ALS to a diffraction limited light source. The current plan is to replace all the vacuum and magnet components while retaining the existing 500 MHz main and third-harmonic, passively operated, rf cavities, but replacement of the existing rf cavities is also being considered. A new feature, is represented by beam-loading transients associated with a beam consisting of 11 bunch trains separated by 10 ns gaps as needed to enable on-axis swap-out injection. In this paper we study these transients and the associated bunch-to-bunch phase, length, and profile variations.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAK037
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THPAL020	Design of Asymmetric Quadrupole Gradient Bending R&D Magnet for the Advanced Light Source Upgrade (ALS-U)	3667
	J.-Y. Jung, M. Leitner, N. Li, E.R. San Mateo, C. Steier, C.A. Swenson, M. Venturini LBNL, Berkeley, California, USA
	Lawrence Bekerley National Laboratory (LBNL) is en-gaged in the development of magnets for the upgrade of the ALS synchrotron (ALS-U) [1]. The proposed ALS-U lattice is a 9-bend achromat reproducing the existing 12-fold symmetric ALS foot print. The ALS-U lattice requires strong focusing elements and the dipole magnet requires high gradient larger than 46 T/m. This paper presents the detailed design of the R&D dipoles under construction.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL020
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THPMF036	Status of the Conceptual Design of ALS-U	4134
	C. Steier, A.P. Allézy, A. Anders, K.M. Baptiste, E.S. Buice, K. Chow, G.D. Cutler, S. De Santis, R.J. Donahue, D. Filippetto, J.P. Harkins, T. Hellert, M.J. Johnson, J.-Y. Jung, S.C. Leemann, D. Leitner, M. Leitner, T.H. Luo, H. Nishimura, T. Oliver, O. Omolayo, J.R. Osborn, G.C. Pappas, S. Persichelli, M. Placidi, G.J. Portmann, S. Reyes, D. Robin, F. Sannibale, C. Sun, C.A. Swenson, M. Venturini, S.P. Virostek, W.L. Waldron, E.J. Wallén LBNL, Berkeley, California, USA
	Funding: This work was supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The ALS-U conceptual design promises to deliver diffraction limited performance in the soft x-ray range by lowering the horizontal emittance to about 70 pm rad resulting in two orders of brightness increase for soft x-rays compared to the current ALS. The design utilizes a nine bend achromat lattice, with reverse bending magnets and on-axis swap-out injection utilizing an accumulator ring. This paper shows some aspects of the completed conceptual design of the accelerator, as well as some results of the R&D program that has been ongoing for the last years.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMF036
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THPMF078	Simulation of Trajectory Correction in Early Commissioning of the Advanced Light Source Upgrade	4256
	T. Hellert, J.-Y. Jung, S.C. Leemann, H. Nishimura, D. Robin, F. Sannibale, C. Steier, C. Sun, C.A. Swenson, M. Venturini LBNL, Berkeley, California, USA
	Funding: *Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231. The ALS upgrade into a diffraction-limited soft x-rays light source requires a small emittance, which is achieved by much stronger focusing than in the present ALS. Very strong focusing elements and a relatively small vacuum chamber make the required rapid commissioning a significant challenge. This paper will describe the progress towards a start-to-end simulation of the machine commissioning and present first simulation results.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMF078
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Compensation of Insertion Device Induced Emittance Variations in Ultralow Emittance Storage Rings

1751

F. Sannibale, S.C. Leemann, H. Nishimura, D. Robin, C. Steier, C. Sun, M. Venturini
LBNL, Berkeley, California, USA

Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231.
With the advent of multi-bend achromat lattices, extremely low emittances are to become the norm in storage ring-based X-ray photon sources. In these lattices, the ratio of beam energy lost to radiation in the Insertion Devices (IDs) to the overall beam energy loss is relatively larger than in 3rd generation light sources. As a result, these machines are more sensitive to the energy loss variations occurring as the users operate variable-gap IDs and to the concurrent variations in radiation damping time, equilibrium emittance, and ultimately transverse properties of the beam. With possibly tens of variable gap IDs continuously and independently varying their gaps to meet the experiment needs, the resulting variation in emittance and beam sizes can be significant and can jeopardize the experimental performance in some of the beamlines. In this paper we describe and discuss possible methods for compensating such emittance variations and maintaining constant transverse beam properties for the experiments.

Slides WEXGBE2 [4.543 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEXGBE2

Export •

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

THPAK037

Beam-Loading Transients and Bunch Shape in the Operation of Passive Harmonic Cavities in the ALS-U

3298

SUSPF073

use link to see paper's listing under its alternate paper code

Z. Pan, S. De Santis, C. Steier, C. Sun, M. Venturini
LBNL, Berkeley, California, USA
T. Hellert
DESY, Hamburg, Germany
C.-X. Tang
TUB, Beijing, People's Republic of China

The ALS-U is a major upgrade of the LBNL ALS to a diffraction limited light source. The current plan is to replace all the vacuum and magnet components while retaining the existing 500 MHz main and third-harmonic, passively operated, rf cavities, but replacement of the existing rf cavities is also being considered. A new feature, is represented by beam-loading transients associated with a beam consisting of 11 bunch trains separated by 10 ns gaps as needed to enable on-axis swap-out injection. In this paper we study these transients and the associated bunch-to-bunch phase, length, and profile variations.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAK037

Export •

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

THPAL020

Design of Asymmetric Quadrupole Gradient Bending R&D Magnet for the Advanced Light Source Upgrade (ALS-U)

3667

J.-Y. Jung, M. Leitner, N. Li, E.R. San Mateo, C. Steier, C.A. Swenson, M. Venturini
LBNL, Berkeley, California, USA

Lawrence Bekerley National Laboratory (LBNL) is en-gaged in the development of magnets for the upgrade of the ALS synchrotron (ALS-U) [1]. The proposed ALS-U lattice is a 9-bend achromat reproducing the existing 12-fold symmetric ALS foot print. The ALS-U lattice requires strong focusing elements and the dipole magnet requires high gradient larger than 46 T/m. This paper presents the detailed design of the R&D dipoles under construction.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPAL020

Export •

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

THPMF036

Status of the Conceptual Design of ALS-U

4134

C. Steier, A.P. Allézy, A. Anders, K.M. Baptiste, E.S. Buice, K. Chow, G.D. Cutler, S. De Santis, R.J. Donahue, D. Filippetto, J.P. Harkins, T. Hellert, M.J. Johnson, J.-Y. Jung, S.C. Leemann, D. Leitner, M. Leitner, T.H. Luo, H. Nishimura, T. Oliver, O. Omolayo, J.R. Osborn, G.C. Pappas, S. Persichelli, M. Placidi, G.J. Portmann, S. Reyes, D. Robin, F. Sannibale, C. Sun, C.A. Swenson, M. Venturini, S.P. Virostek, W.L. Waldron, E.J. Wallén
LBNL, Berkeley, California, USA

Funding: This work was supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The ALS-U conceptual design promises to deliver diffraction limited performance in the soft x-ray range by lowering the horizontal emittance to about 70 pm rad resulting in two orders of brightness increase for soft x-rays compared to the current ALS. The design utilizes a nine bend achromat lattice, with reverse bending magnets and on-axis swap-out injection utilizing an accumulator ring. This paper shows some aspects of the completed conceptual design of the accelerator, as well as some results of the R&D program that has been ongoing for the last years.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMF036

Export •

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

THPMF078

Simulation of Trajectory Correction in Early Commissioning of the Advanced Light Source Upgrade

4256

T. Hellert, J.-Y. Jung, S.C. Leemann, H. Nishimura, D. Robin, F. Sannibale, C. Steier, C. Sun, C.A. Swenson, M. Venturini
LBNL, Berkeley, California, USA

Funding: *Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231.
The ALS upgrade into a diffraction-limited soft x-rays light source requires a small emittance, which is achieved by much stronger focusing than in the present ALS. Very strong focusing elements and a relatively small vacuum chamber make the required rapid commissioning a significant challenge. This paper will describe the progress towards a start-to-end simulation of the machine commissioning and present first simulation results.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPMF078

Export •

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