Transcript BLM System Design

LCLS Undulator Systems
Beam Loss Monitor
William Berg
10.31.07
Beam Loss Monitor
ANL/APS Diagnostics Group
William Berg
[email protected]
Introduction
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Physics Requirements Document: Heinz-Dieter Nuhn 9-28-07
(prd: 1.4-005-r0 undulator beam loss monitor).
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Scope Reduction: diagnostic to mps detector.
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Purpose and Requirements.
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Budget: M&S 500k (325k detector, ctls/mps 175k).
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Schedule: (design: nov-mar, test: feb-mar, fab: mar-jun, inst: july).
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Organization: 4 groups.
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Group Definition: controls, detector, simulation, test & calibration.
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Design Highlights and System Overview (detectors: dynamic 33, static: 2, r&d fiber:1).
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Detector design details and focus topics.
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Funds are limited and efforts need to be focused to minimize costs (h-dn).
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Simulation of losses and damage in the undulator will proceed in parallel with the present effort (pk).
10.31.07
Beam Loss Monitor
William Berg
[email protected]
BLM Purpose
h-dn
The BLM will be used for two purposes:
A: Inhibit bunches following an “above-threshold” radiation event.
B: Keep track of the accumulated exposure of the magnets in each undulator.
Purpose A is of highest priority. It will be integrated into the Machine
Protection System (MPS) and requires only limited dynamic range from
the detectors.
Purpose B is also desirable for understanding long-term magnet damage
in combination with the undulator exchange program but requires a large
dynamic range for the radiation detector (order 106 ?) and much more
sophisticated diagnostics hard and software.
10.31.07
Beam Loss Monitor
William Berg
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BLM requirements
pk
Primary function of the BLM is to indicate to the MPS if
losses exceed preset thresholds.
MPS processor will rate limit the beam according to which
threshold was exceeded and what the current beam rate is.
The thresholds will be empirically determined by inserting a
thin obstruction upstream of the undulator.
Simulation of losses and damage in the undulator will
proceed in parallel with the present effort.
10.31.07
Beam Loss Monitor
William Berg
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Draft Budget Breakdown
500k M&S Total
325k Detector Development
25k Interface Box
150k Control and MPS integration
25k link node chassis
25k long haul cables
50k davis bacon labor
15k ctl modules and signal conditioning electronics
25k clean power distribution
10k racks
10.31.07
Beam Loss Monitor
William Berg
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Draft schedule
detector
detector design prototype
prototype fabrication
prototype testing (beam)
detector design lock
detector fabrication
detector assembly
ship to slac
installation
nov
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dec
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march
april
may
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june
july
aug
sept
x
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mps and infrastructure
cable plant (utility bldg)
cable plant (tunnel)
rack power
tunnel racks
mps system
calibration plan
start
finish
feb
x
interface box
prototype
testing
design lock
custom control/sc boards
ckt brd prototype design
ckt brd prototype fabrication
control/sc prototype test
control/sc proto test (beam)
design lock
fabrication
system build
installation
jan
x
x
x
x
x
x
simulation (ongoing effort)
10.31.07
Beam Loss Monitor
William Berg
[email protected]
LCLS MPS Beam Loss Monitor
System Engineer: W. Berg
Cost Account Manager: G. Pile
Scientific advisor: P. Krejcik*
Scientific advisor: B. Yang
Controls/MPS Group
Lead (ctls) : J. Stein
Lead (mps): A. Alacron*
M. Brown *
R. Diviero
E. Norum
S. Norum *
B. Laird
J. Dusatko*
Detector Group
Technical Manager: D. Walters
FEL Physics: H. Nuhn*
FEL Physics: P. Emma*
Simulations and
analysis Group
Testing and Calibration
Group
Lead: W. Berg
Lead: M. White
A. Brill
L. Erwin
R. Keithley
J. Morgan
J. Dooling
B. Yang
Lead: B. Yang
W. Berg
J. Bailey
J. Dooling
L. Moog
E. Norum
M. White
* Slac employee
10.31.07
Beam Loss Monitor
William Berg
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MPS Beam Loss Monitor Group Functions
Controls Group:
J stein, A. Alacron
Develop BLM control and mps system:
Interface Box and Control.
PMT Signal Conditioning.
Control and MPS Integration and User Displays.
Detector Group: W. Berg
Develop Detector and Interface.
Simulations and Analysis Group:
M. White
Provide collaborative blm simulation support and test analysis.
Test and Calibration Group:
B. Yang
Provide beam based hardware testing programs and calibration plan.
10.31.07
Beam Loss Monitor
William Berg
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Design Highlights
33 distributed detectors (one preceding each undulator segment), two static units (up and
downstream of undulator hall).
One additional channel reserved for r&d fiber based system.
Dynamic detector (tracks with undulator) 100mm stroke. Undulator position (in/out) detection will be
used to set the corresponding mps threshold levels.
Large area sensor (coverage of the full horizontal width of top and bottom magnet blocks).
Manual insertion option via detachable arm for special calibration and monitoring.
Fiber Out for low gain upgrade (full integration and dyn range diagnostic), system expandable to 80
channels.
MPS threshold detection and beam rate limiting.
Single pulse detection and mps action up to max 120Hz beam rep rate via dedicated mps link.
Monitoring of real time shot to shot signal levels and record integrated values up to one second.
Heart beat led pulser for system validation before each pulse up to full rep rate (pseudo calibration).
Remote sensitivity adjust (dynamic range) by epics controlled PMT dc power supply (600-1200V).
Calibrated using upstream reference foil (initial use cal will be determined from simulation studies).
Radiation hard detector (materials and electronics).
10.31.07
Beam Loss Monitor
William Berg
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BLM Controls Architecture
pk
The BLM PMT interfaces to the MPS link node chassis.
The IO board of the MPS link node chassis provides the
ADC & DAC for the PMT.
A detector interface box (pmt, led pulser, sig con?) is the
treaty point between the MPS and the undulator BLM.
There are 5 link node chasses serving up to 8 BLMs along
the undulator (expandable from 8 to16 channels).
10.31.07
Beam Loss Monitor
William Berg
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Undulator Hardware
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10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35
Spares
Spares
LINK
NODE
10.31.07
Beam Loss Monitor
LINK
NODE
LINK
NODE
LINK
NODE
LINK
NODE
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Beam Loss Monitors with Link Nodes
Use Link Node to
support analog I/O IndustryPack modules
provide analog readouts to control system
set threshold levels
control HV power supplies
control LED Pulser
10.31.07
Beam Loss Monitor
William Berg
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Segment Design Layout
m. brown
MPS
Link
Node
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Beam Loss Monitor
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BLM Interconnect Diagram
10.31.07
Beam Loss Monitor
m. brown
William Berg
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Interface Box Location
10.31.07
Beam Loss Monitor
William Berg
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Plan View of Short Drift
10.31.07
Beam Loss Monitor
William Berg
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BFW Pump Out Port Relocation
10.31.07
Beam Loss Monitor
William Berg
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Removable Pin for Manual Insertion
10.31.07
Beam Loss Monitor
William Berg
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Undulator Inserted Position
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Beam Loss Monitor
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Undulator Retracted Position
10.31.07
Beam Loss Monitor
William Berg
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Magnet Block Sensor Coverage
10.31.07
Beam Loss Monitor
William Berg
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Rendering of Detector
10.31.07
Beam Loss Monitor
William Berg
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Cross Section of BLM Detector
10.31.07
Beam Loss Monitor
William Berg
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Proposed PMT Device -04 (420nm)
10.31.07
Beam Loss Monitor
William Berg
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BLM System Support Focus Topics
1.
Assignment of Eric Norum to controls design oversight and testing.
2.
Funding of beam based prototyping and test program.
3.
Group Leaders to significantly step up direct involvement in system
oversight, program implementation, and schedule tracking (controls:
n. arnold, diag: g. decker, lcls: g. pile, ops/analysis: m. borland).
4.
Active participation in simulations and simulation priority from slac.
5.
Implementation of upstream profile monitor (halo or at min. cal foil).
6.
Adequate analysis and shielding of upstream beam dump.
7.
Develop long term collaboration plan for the pursuit of determining
magnet damage mechanisms and thresholds via empirical methods.
8.
Determine need and priority of BLM signal integration (diagnostic).
10.31.07
Beam Loss Monitor
William Berg
[email protected]
Summary
 Undulator magnets protection is critical for machine commissioning period.
 Schedule for development of the blm program is very aggressive and Funding is limited.
 System design and fabrication must go in parallel with simulation and testing program.
 Consider Minimum requirements for first level implementation. Taking advantage of
existing mps infrastructure.
 BLM system is now defined as a component of the mps with an upgrade path to a
diagnostic (low gain detector).
 36 distributed channels (2 static devices) capable of single pulse detection and rate
limiting reaction.
 Detectors track with undulator position with detach option for manual operation.
 Calibration plan and hardware is vital to proper system operation (threshold detection will
use empirically derived levels).
10.31.07
Beam Loss Monitor
William Berg
[email protected]