IPAC2016 - List of Authors (Choi, J.)

Paper	Title	Page
WEPOW056	Reproducibility of Orbit and Lattice at NSLS-II	2976
	J. Choi, T.V. Shaftan BNL, Upton, Long Island, New York, USA
	Funding: DOE contract No: DE-SC0012704 In operating a high-end synchrotron light source, like NSLS-II, it is important to understand the machine accurately and have the ability to reproduce the desired machine state when needed. The obstacles, we can imagine, include the magnet hysteresis effect and some environmental effects. To minimize hysteresis effect, we cycle the magnets and it was proved working properly. On the other hand, from the point of long-term operation, we are not yet satisfied with the reproducibilities given by the same set of magnet currents and the machine needs additional tuning processes. In this paper, the experience of NSLS-II operation and studies are presented.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPOW057	Spectral Analysis of Turn-by-Turn Data	2979
	J. Choi BNL, Upton, Long Island, New York, USA
	Funding: DOE contract No: DE-SC0012704 With the recent technical developments, it is now popular to get the turn-by-turn data for the storage ring. Even though response matrix based analysis, like LOCO, have strong advantages in lattice analysis, the turn-by-turn data analysis is quite attractive because it takes very short time in data acquisition and many effective analyzing methods have been developed. Basically, such analysis requires accurate estimation of peaks of frequency spectra with high resolution. In this paper, we review the various accuratenesses of such estimations depending on processes using exact sinusoidal data and apply the end-matching method to simulation and measurement.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOY021	NSLS-II Dedicated Python Tools for Simulation and Analysis	4134
	J. Choi BNL, Upton, Long Island, New York, USA
	Funding: DOE contract No: DE-SC0012704 Python is a high-level interpreted programming language. Despite its slow benchmarks, because of its fast coding cycle and dynamic property, the users are increasing fast in all areas. Also, because it does not need special care for the memory management, both professional and non-professional programmers can easily make bug-free code just by concentrating on logics. Furthermore, fast increasing libraries are making the language more and more useful. With these advantages, we developed python tools which simulate and analyze the particle accelerator with some parts being dedicated to NSLS-II operation.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOY022	Database Development for NSLS-II Accelerator Data Management	4137
	J. Choi, T.V. Shaftan BNL, Upton, Long Island, New York, USA
	Funding: DOE contract No: DE-SC0012704 NSLS-II is developing a database which will be used for the accelerator data management. The information related to the operation is the main target at this stage. Also, various documents are being collected to provide easy access and installing workflow management is under consideration. The database will have web-based interfaces to communicate with the users. This paper overviews the database structures and required functionalities.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOY023	Upgrade of NSLS-II Active Interlock System	4140
	S. Seletskiy, J. Choi, K. Ha, R.M. Smith BNL, Upton, Long Island, New York, USA
	The NSLS-II Storage Ring is protected from possible damage from synchrotron radiation by a dedicated active interlock system (AIS). The AIS monitors electron beam position and angle and triggers beam drop if beam orbit exceeds the boundaries of pre-calculated active interlock envelope. The one year worth of the AIS operation showed that there is a number of erroneous machine trips associated with the AIS. In this paper we describe an upgrade of the AIS that allowed us to get rid of the Storage Ring faults and improved the overall NSLS-II reliability.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPOY048	NSLS-II Active Interlock System and Post-Mortem Architecture	4214
	K. Ha, E.B. Blum, W.X. Cheng, J. Choi, Y. Hu, D. Padrazo, S. Seletskiy, O. Singh, R.M. Smith, J. Tagger, Y. Tian, G. Wang, T. Yang BNL, Upton, Long Island, New York, USA
	The NSLS-II at Brookhaven National Laboratory (BNL) started the user beam service in early 2015, and is currently operating 13 of the insertion device (ID) and beamlines as well as constructing new beamlines. The fast machine protection consists of an active interlock system (AIS), beam position monitor (BPM), cell controller (CCs) and front-end (FE) systems. The AIS measures the electron beam envelop and the dumps the beam by turning off RF system, and then the diagnostic system provides the post-mortem data for an analysis of which system caused the beam dump and the machine status analysis. NSLS-II post-mortem system involves AIS, CCs, BPMs, radio frequency system (RFs), power supply systems (PSs) as well as the timing system. This paper describes the AIS architecture and PM performance for NSLS-II safe operations.
Export •	reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Reproducibility of Orbit and Lattice at NSLS-II

2976

J. Choi, T.V. Shaftan
BNL, Upton, Long Island, New York, USA

Funding: DOE contract No: DE-SC0012704
In operating a high-end synchrotron light source, like NSLS-II, it is important to understand the machine accurately and have the ability to reproduce the desired machine state when needed. The obstacles, we can imagine, include the magnet hysteresis effect and some environmental effects. To minimize hysteresis effect, we cycle the magnets and it was proved working properly. On the other hand, from the point of long-term operation, we are not yet satisfied with the reproducibilities given by the same set of magnet currents and the machine needs additional tuning processes. In this paper, the experience of NSLS-II operation and studies are presented.

Export •

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

WEPOW057

Spectral Analysis of Turn-by-Turn Data

2979

J. Choi
BNL, Upton, Long Island, New York, USA

Funding: DOE contract No: DE-SC0012704
With the recent technical developments, it is now popular to get the turn-by-turn data for the storage ring. Even though response matrix based analysis, like LOCO, have strong advantages in lattice analysis, the turn-by-turn data analysis is quite attractive because it takes very short time in data acquisition and many effective analyzing methods have been developed. Basically, such analysis requires accurate estimation of peaks of frequency spectra with high resolution. In this paper, we review the various accuratenesses of such estimations depending on processes using exact sinusoidal data and apply the end-matching method to simulation and measurement.

Export •

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

THPOY021

NSLS-II Dedicated Python Tools for Simulation and Analysis

4134

J. Choi
BNL, Upton, Long Island, New York, USA

Funding: DOE contract No: DE-SC0012704
Python is a high-level interpreted programming language. Despite its slow benchmarks, because of its fast coding cycle and dynamic property, the users are increasing fast in all areas. Also, because it does not need special care for the memory management, both professional and non-professional programmers can easily make bug-free code just by concentrating on logics. Furthermore, fast increasing libraries are making the language more and more useful. With these advantages, we developed python tools which simulate and analyze the particle accelerator with some parts being dedicated to NSLS-II operation.

Export •

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

THPOY022

Database Development for NSLS-II Accelerator Data Management

4137

J. Choi, T.V. Shaftan
BNL, Upton, Long Island, New York, USA

Funding: DOE contract No: DE-SC0012704
NSLS-II is developing a database which will be used for the accelerator data management. The information related to the operation is the main target at this stage. Also, various documents are being collected to provide easy access and installing workflow management is under consideration. The database will have web-based interfaces to communicate with the users. This paper overviews the database structures and required functionalities.

Export •

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

THPOY023

Upgrade of NSLS-II Active Interlock System

4140

S. Seletskiy, J. Choi, K. Ha, R.M. Smith
BNL, Upton, Long Island, New York, USA

The NSLS-II Storage Ring is protected from possible damage from synchrotron radiation by a dedicated active interlock system (AIS). The AIS monitors electron beam position and angle and triggers beam drop if beam orbit exceeds the boundaries of pre-calculated active interlock envelope. The one year worth of the AIS operation showed that there is a number of erroneous machine trips associated with the AIS. In this paper we describe an upgrade of the AIS that allowed us to get rid of the Storage Ring faults and improved the overall NSLS-II reliability.

Export •

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

THPOY048

NSLS-II Active Interlock System and Post-Mortem Architecture

4214

K. Ha, E.B. Blum, W.X. Cheng, J. Choi, Y. Hu, D. Padrazo, S. Seletskiy, O. Singh, R.M. Smith, J. Tagger, Y. Tian, G. Wang, T. Yang
BNL, Upton, Long Island, New York, USA

The NSLS-II at Brookhaven National Laboratory (BNL) started the user beam service in early 2015, and is currently operating 13 of the insertion device (ID) and beamlines as well as constructing new beamlines. The fast machine protection consists of an active interlock system (AIS), beam position monitor (BPM), cell controller (CCs) and front-end (FE) systems. The AIS measures the electron beam envelop and the dumps the beam by turning off RF system, and then the diagnostic system provides the post-mortem data for an analysis of which system caused the beam dump and the machine status analysis. NSLS-II post-mortem system involves AIS, CCs, BPMs, radio frequency system (RFs), power supply systems (PSs) as well as the timing system. This paper describes the AIS architecture and PM performance for NSLS-II safe operations.

Export •

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