1. Photon beamline crates
Contents
introduction
Attempt to list where crates are used at FLASH and where they might be used at XFEL, whether modifications are required etc.
instruments and their crates
Gas Monitor Detector - GMD
Beam Position Measurement - BPM
Photo-electron spectrometer
Motor controllers
Pump laser
Experiment End Stations
Small user end station
Large 2D pixel detector end station
04.Dec.2007
Crate standard workshop - C.Youngman

2. Crate standard workshop - C.Youngman
Remember …
Most of this information is new to me, so I have probably
… misinterpreted information
… missed out crate users at FLASH
… missed proposed crate systems for XFEL
04.Dec.2007
Crate standard workshop - C.Youngman

3. Gas Monitor Detector - GMD
At FLASH
Measures photon beam intensity and x-y position
Ionization electrons => position
Integrated current measurement of ionization ions => beam intensity
2 GMDs per beamline and per experiment => 20 total
1 VME crate per GMD
Single board SPARC cpu, runs DOOCS server, software Rehlich and GMD group
Readout boards: timing control, digital intputs/outputs, ADCs, integrator, etc.
Slow control: HV controller
For use at FLASH
Photoionization cross-section lower
Detector eXtended GMD (XGMD) => increases meas. length, amplifies signal, …
increase ADC and integrator resolution and speed
Improve resolution of timer system
Conclusion
Single crate solution preferred, upgrades are required for XFEL usage which could allow a change of crate, most boards provided by MCS group
04.Dec.2007
Crate standard workshop - C.Youngman

4. Gas Monitor Detector - GMD
At FLASH
04.Dec.2007
Crate standard workshop - C.Youngman

5. Beam Position Measurement - BPM
At FLASH
Beam position monitoring from electron ionization signal of GMD – will not work at XFEL, due to lower rate
At XFEL
Use instead a Flourescent screen plus Micro Channel Plate detector to visualize the position.
Basler Camera readout via PC using firewire.
This is no longer a crate system, and the firewire/PC might be replaced by a ethernet connection.
04.Dec.2007
Crate standard workshop - C.Youngman

6. Photo-electron spectrometer
Prototype being built at FLASH
Measures spectral distribution of each photon bunch
8 GHz sampling
mean photon energy, bandwidth, higher harmonic content, spectral distribution Readout via Acquiris system (scope without the display)
Compact PCI bus system
Alternative to VME crate, it‘s newer so ADCs are faster
Could be a candidate crate for the upgraded GMD system
Single crate solution so could be a portable GMD for use elsewhere
Access to timing and event ID information via compactPCI timing board – works(?)
DOOCS server is available
Data stored on internal disk
Looks like another standard
04.Dec.2007
Crate standard workshop - C.Youngman

7. Crate standard workshop - C.Youngman
Motor control
At FLASH
Drives appertures, mirror movements, invasive beam monitpring equipment
Currently VME based
Controller/steping boards sit in crate
PC sitting outside crate drives boards
8 crates with ~100 drive channels
At XFEL
100 channels per beamline, 5 beamlines
Current solution is limited usually not possible to drive channels in parallel(?). Cantidate for a new implementation?
04.Dec.2007
Crate standard workshop - C.Youngman

8. Crate standard workshop - C.Youngman
Pump laser
Optical laser used to pump the sample
Two VME crates used to control/monitor the system
Was not able to get additional information on time
PG2
BL1
BL3
BL2
Optischer LASER
04.Dec.2007
Crate standard workshop - C.Youngman

9. Crate standard workshop - C.Youngman
Small user end station
At FLASH
1 VME crate user end station per beamline
Timing information
Trigger signals
Event ID
Controls via DOOCS
Experimenters store data on scope or laptop, analyse at home
At XFEL
Does this exist at XFEL – yes
Must work at other non XFEL loactions ?
Could be upgraded to a new standard is all required functionality provided.
04.Dec.2007
Crate standard workshop - C.Youngman

10. Large 2D pixel detector end station
3 detectors have submitted proposals/LoI:
HPAD – Hybrid Array Pixel Detector
LPD – Large Pixel Detector
LSDD – Linear Silicon Drift detector
Detectors: ~2MB, ~400 frames/bunchtrain digitized, all data archived.
A common frontend/backend/archive solution is being looked at by HPAD and LSDD, possibly by LPD
Frontend readout modules sends data to a PC farm
PC farm builds complete frames and then bunchtrains
Data archived to tape silos in DESY computer center
Designs still being worked on.
04.Dec.2007
Crate standard workshop - C.Youngman

11. Large 2D pixel detector end station
LPD
Originally ATCA crate proposed for data processing card
MicroTCA now favoured
LPD request TCA based solutions should not be excluded from standard
LSDD
Idea: readout ASIC and transfer data via custom protocol to crates (candidates ATCA, CompactPCI,…), where data is reorganized and sent via network IP protocol to backend
04.Dec.2007
Crate standard workshop - C.Youngman

12. HPAD frontend overview
04.Dec.2007
Crate standard workshop - C.Youngman

13. Large 2D pixel detector end station
Preliminery ideas w.r.t. crates to be used, for HPAD
Timing signals
Fast bunch veto signal
Start bunchtrain
+ bunch clock
CompactPCI/PXI,
possibly ATCA
crate
Vbias PS
SC propriety crates
DESY timing standard crate.
Not required if board goes into
main crate. … .. C P U
Field bus … …
Front end modules
Set configuration
Read status
Set Bunchtrain gap vetos
Euro standard crate
– for modules
not requiring bus
Not a crate, but modules in
some mechanical framework
on the detector head
Frontend modules
04.Dec.2007
Crate standard workshop - C.Youngman

14. Crate standard workshop - C.Youngman
HPAD crates
CompactPCI/PXI rather than ATCA
Availability of commercial boards for:
Slow ADCs
Digital I/O
Fieldbus interface …
Also important
More than one user group with different slow control requirements.
External data
Timing system input required
Access to slow (bunchtrain) data from network
04.Dec.2007
Crate standard workshop - C.Youngman

15. Crate standard workshop - C.Youngman
Conclusions
There are many crate based systems in the photon beamline, both experiments and beam monitoring systems.
A standard crate could be introduced most easily where:
An upgrade is required, e.g. GMD
A new installation is planed, e.g. 2D pixel detectors.
04.Dec.2007
Crate standard workshop - C.Youngman