erl time management system -...

17
Energy Recovery Linac’s (ERL) Time Management System Prerana Kankiya Brookhaven National Laboratory New York, USA

Upload: dinhkhuong

Post on 04-Apr-2018

217 views

Category:

Documents


1 download

TRANSCRIPT

Energy Recovery Linac’s (ERL) Time Management

System

Prerana Kankiya Brookhaven National Laboratory

New York, USA

ICALEPCS 2015, Melbourne Australia ERL Time Management System

ERL

E-lens 10’clock

PHEONIX 8’clock

STAR 6’clock

CEC 2’clock

NSRL LINAC

EBIS

TANDEM

ICALEPCS 2015, Melbourne Australia ERL Time Management System

Tell’em what you are going to tell

• Introduction to ERL and its timing needs • Hardware components of timing system • Beam structure • Software algorithm and its features • Test scheme and Operational results • Operator interface • Status and plans

ICALEPCS 2015, Melbourne Australia ERL Time Management System

• For low energy electron cooling of RHIC (LeRec) and electron ion collider (eRHIC) • These applications require up to 350 milli ampere CW current with low emittance

ERL LAYOUT

ICALEPCS 2015, Melbourne Australia ERL Time Management System

Required Bunch Structure

Fig. 2 Bunch Train

Bunch pattern for ramping up beam current for fault studies

1 car with 1 bunch at 1Hz 1s

2 car with 1 bunch at 1Hz

14 car with 1 bunch at 1Hz

14 car with 2 bunch at 1Hz

100 μs

Group of laser pulses = Bunch Groups of Bunches = car

Group of Cars = Train

ICALEPCS 2015, Melbourne Australia ERL Time Management System

Required Bunch Structure

0 20 40 60 80 100

Time( sec)

Solenoid

RF

laser gate

laser pulses

camera triggers

BPM

Faraday Cups

Fig. 1 Sequence of Triggers

Fig. 2 Bunch Train

Bunch pattern for ramping up beam current for fault studies

1 car with 1 bunch at 1Hz 1s

2 car with 1 bunch at 1Hz

14 car with 1 bunch at 1Hz

14 car with 2 bunch at 1Hz

100 μs

ICALEPCS 2015, Melbourne Australia ERL Time Management System

Building Blocks of the Timing System

• Red items are software entities configured by timing ADO. • Blue Arrows are HW triggers/permits V202: Delay modules programmed at BNL DG: Stanford Research System Delay Generator model 645.

V202#1

3 4 5 6

0 1 2

7

CLK

EXT

INH EXT AB CD EF GH

DG #1 V202 #2

3 4 5 6

0 1 2

7

CLK

EXT

INH EXT AB CD EF GH

DG #2

INH EXT AB CD EF GH

DG #3

INH EXT AB CD EF GH

DG #4

OPERATOR INTERFACE

Master Timing Accelerator Device Object

(ADO)

INHIBIT LOGIC

RF Electronics operating at 703 Mhz.

Phase locked with Laser

RHIC Event Link Generator embarks the start of Train at

1Hz

To Devices

ICALEPCS 2015, Melbourne Australia ERL Time Management System

Building Blocks of the Timing System

• Red items are software entities configured by timing ADO. • Blue Arrows are HW triggers/permits V202: Delay modules programmed at BNL DG: Stanford Research System Delay Generator model 645.

V202#1

3 4 5 6

0 1 2

7

CLK

EXT

INH EXT AB CD EF GH

DG #1 V202 #2

3 4 5 6

0 1 2

7

CLK

EXT

INH EXT AB CD EF GH

DG #2

INH EXT AB CD EF GH

DG #3

INH EXT AB CD EF GH

DG #4

OPERATOR Interface

Master Timing Accelerator Device

Object (ADO)

ICALEPCS 2015, Melbourne Australia ERL Time Management System

Building Blocks of the Timing System

• Red items are software entities configured by timing ADO. • Blue Arrows are HW triggers/permits V202: Delay modules programmed at BNL DG: Stanford Research System Delay Generator model 645.

V202#1

3 4 5 6

0 1 2

7

CLK

EXT

INH EXT AB CD EF GH

DG #1 V202 #2

3 4 5 6

0 1 2

7

CLK

EXT

INH EXT AB CD EF GH

DG #2

INH EXT AB CD EF GH

DG #3

INH EXT AB CD EF GH

DG #4

OPERATOR Interface

Master Timing Accelerator Device

Object (ADO)

INHIBIT LOGIC

RF Electronics operating at 703 Mhz.

Phase locked with Laser

RHIC Event Link Generator embarks the start of Train at

1Hz

To Devices

Burst of Cars

ICALEPCS 2015, Melbourne Australia ERL Time Management System

Algorithm Goal: LASER is last device to be fired

• Set response time of all diagnostics, done by system experts manually. (δdev)

• Find device with maximum response time (δmax) δmax = MAX(δdev1 + δdev2 + δdev3 + δdev4 + δdev5 ……..)

• Calculate total insertion delay due to 4 DG645 boxes. (InsertionDelaymax )

• Set delay (Tdev)of each channel to Tdev = δmax + InsertionDelaymax - δdev

ICALEPCS 2015, Melbourne Australia ERL Time Management System

EASE OF USE • Calculate and compensate insertion delays of each

DG645 unit. • Calculate delays in clock ticks of laser and internal

clock when in test and operation mode. • Change trigger properties based on change in train

properties. • Check for Beam Power Limits. • Cater to electronics with special needs and supply

reset triggers based on time constant of each.

ICALEPCS 2015, Melbourne Australia ERL Time Management System

User Interface

ICALEPCS 2015, Melbourne Australia ERL Time Management System

Bunch Frequency is the spacing of

the cars

Bunch Width is the length of

the car

Burst Count is Number of Cars to be

generated

Number of laser pulses in a car = 9.38 MHz * Bunch Width

ICALEPCS 2015, Melbourne Australia ERL Time Management System

Beam Diagnostic Systems

ICALEPCS 2015, Melbourne Australia ERL Time Management System

Putting It All Together

ICALEPCS 2015, Melbourne Australia ERL Time Management System

Truth Be Told!

• 4 pulse outputs • 8 delay outputs • <25 ps rms jitter • Trigger rates to 10 MHz

Limitations: • Cannot disable individual output channel • Rate error status limits the configurable delay value range • Pre-scale trigger factor is not synchronized with external trigger.

ICALEPCS 2015, Melbourne Australia ERL Time Management System

SUMMARY

• Electron beam was generated. Yay! • Fault studies are underway utilizing the synchronized beam

instruments and diagnostics at ERL. • Work continues to improve operator interface to minimize

user intervention and include more systems. • MRF Timing system or White Rabbit are potential options

for future stand alone research project.

THANK YOU!