Fermi Large Area Telescope

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Fermi Large Area Telescope Tutorial on Science
Analysis Data Access Tony Johnson Stanford
Linear Accelerator Center tonyj_at_slac.stanford.edu
http//glast-ground.slac.stanford.edu/DataPortal
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Data Portal Components

• The Data Portal Comprises
• Astro Server
• Common History
• Fits Skimmer
• Merit Skimmer
• Data Catalog
• Web Interface
• Linemode Client
• Download Manager
• Web Interface
• Command Line
• WIRED Event Display
• This talk will only cover the items in red.

All components available via the web interface
at http//glast-ground.slac.stanford.edu/DataPort
al
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Astro Server
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Astro Server

• Allows data to be selected based on any
  combination of
• Energy Range
• Position in sky (ra,dec,radius)
• Position can be looked up in SIMBAD catalog
• Event Class (transient, source, diffuse)
• Time Range (MET)
• Can produce FT1 (fits), FT2 (fits) and/or Merit
  (root)
• Supports multiple Event Samples
• Currently LEOScience or Level1
• Can support access to multiple versions of data
  once we start reprocessing, or if we want to have
  any kind of special event selections
• Level1 data currently loaded as soon as it
  becomes available from pipeline
• Web and command line interfaces available

Coming Soon
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Astro Server Web Interface
Page pre-populated with your most recent selection
You can give job meaningful name
Leave fields blank for no-limit
Give name of astronomical object, sirius, M31,
MCG02-60-010
Expert options allow experimental features to be
easily added
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Astro Server Web Interface
README contains job parameters
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Common History

• Data Portal History can be used
• Show status of all your skimmer/astro server jobs
• To access output directory, pipeline details for
  all jobs
• Recover parameters of any job

Tutorial Demo
Click to go to output directory
Click to go to pipeline
Click to recover parameters
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Common History

• Clicking on job name in history recovers
  parameters
• Allows rerunning same or similar job

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Fits Skimmer
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Fits Skimmer

• Supports merging any FT1/FT2 files in data
  catalog
• Allows fcopy rowfilter style cuts to be applied
  to FT1 columns
• Example
• ZenithAnglelt105 CTBClassLevel3
• http//heasarc.nasa.gov/lheasoft/ftools/headas/row
  filter.html
• Allows selection of data based on meta-data in
  data catalog
• Examples
• sIntentnomSciOps
• LEOScience"1835Survey
• nMootKey2103 nMootKey2104
• Outputs FT1 and FT2 files

Coming Soon
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Fits Skimmer Web Interface
Page pre-populated with your most recent selection
You can give job meaningful name
Row Filter
Data Selection (this is the selection Richard has
been using for making merged FT1/FT2 files)
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Fits Skimmer Web Interface
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Fits Skimmer vs. Astro Server

• Fits Skimmer
• Allows cuts on any FT1 column
• Suitable for merging many files with minimal cuts
• Can output FT1, FT2
• Can be used with any dataset in data catalog
• Fully reads all input files

• Astro Server
• Allows cuts on energy, time, position, event
  class
• Suitable for selecting limited number of events
• Can output FT1, FT2, Merit
• Can only be used with data loaded into database
• Uses database for efficient access to selected
  events

• In future smarter single web interface may
  automatically choose most appropriate backend
  tool.

Coming Soon
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Data Catalog
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Data Catalog

• Allows access to many datasets including Level1
  data, ASP data, Reprocessed data, MC data sets

Key locations allow attention to be drawn to
important datasets
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Data Catalog

• Data Catalog has been designed to be extensible
• Can science groups make better use of data
  catalog?
• Use it to define standard datasets?
• As alternative to sending e-mail with location on
  user disk
• See LEOScience folder as example
• Use meta-data to keep track of common data
  selections
• E.g. goodDatatrue instead of complex set of
  sIntent cuts

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Status

• Working on improving documentation
• Adding FAQs at
• https//confluence.slac.stanford.edu/display/ds/Da
  taAccessFAQ
• Please contribute your own questions (we will try
  to provide the answers)
• Data Portal is now mostly complete
• Most of the planned functionality is available
• Documentation is improving
• We need to work with Science Groups to make sure
  we are making optimal use of the available tools
• We need input from Science Groups (you) on what
  additional features are needed/desired
• E-mail me, or use helpsoftlist_at_glast.stanford.edu

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Discussion Items

• Astro server
• What data should be loaded?
• Currently loaded with all FT1 (including LEO)
  satisfying Richards sIntent cuts
• Should we remove early data?
• Is this is the right set of data?
• Currently all transient, source, diffuse data
  classes
• Original plan was for less data, may need to beef
  up server as we get more data
• Weekly summary DST files?
• What data, when/how to make them?
• Can science groups make better use of data
  catalog?
• Use it to define standard datasets?
• Use meta-data to keep track of common data
  selections