Data Acquisition Integration and

Experiment Automation with Python

• Introduction & Motivation• PyDAS Overview • Summary

Piotr Żołnierczuk

Neutron Scattering Science DivisionOak Ridge National Laboratory

SciPy 2009 Conference, Pasadena, CA

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

Why is neutron scattering useful?

•Neutrality

•Sensitivity to light atoms

•Magnetism

•Energy

References:ORNL NScD: http://neutrons.ornl.gov/Neutron Primer: http://lib-www.lanl.gov/la-pubs/00326651.pdfDANSE Book: http://www.cacr.caltech.edu/projects/danse/ARCS_Book_16x.pdf

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

Spallation Neutron Source

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

Crash Course in Neutron Scattering

n

Detectors

SampleBeam Optics Beam Dump

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

Instrument Examples

REF-M

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SNS DAS Architecture

Real Time

Timing

Control & Events

Slow Controls

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

PyDas History

• Project started as a simple scripting “hook” to the DAS

− soon Instrument Scientists wanted more

• At the moment each instruments is a separate project

− So far only a few instruments, but maintenance is becoming an

issue

− We are consolidating them into common source tree

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

PyDAS Architecture

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

Examples: Scannig in IPyDas

scan_motor('motor1',arange(10.0,90.0,0.5),

scan.RUNTIME,30.0,go_back=True)

scan_plot()

for temp in [273.0,293.0,313.0,333.0]:

tempctrl.value = temp

scan_chopper('Energy',[25.,35.,50],scan.PCHARGE,1e10,

title='The Nobel Prize Data at T=%s K' % temp)

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

IPyDas in Action

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

IPyDas in Action

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

PyDAS in Action

OAK RIDGE NATIONAL LABORATORYU. S. DEPARTMENT OF ENERGY

Summary• PyDAS

− “glues” various DAS devices together

− allows for experiment automation

• Challenges & Future

− need to support 24 different instruments

− high level customization

− currently refactoring and consolidating project

− provide basic data viewing

− new project [?]: C#/.NET + (Iron)Python

Thanks to: Rick Riedel and Xiaodong Tao