Moon Trigger¶

The Moon (and Sun) trigger is aiming to register tracks coming from the Moon (and Sun) direction. Physical meaning of this search is to analyze our possibility to see the shadow of the Moon (Sun) in a flux of cosmic rays. This opens the door to the Far Detector angular resolution estimate as well as Moon (Sun) specific studies such as finding changes of the Moon (Sun) shadow shape to see changes of magnetic environment etc.

Trigger¶

The trigger code is located in the DDT repo: https://cdcvs.fnal.gov/redmine/projects/novaddt/repository/show/trunk/MoonShadowTrigger

The basis of the Moon (Sun) location algorithm is NOVAS (Naval Observatory Vector Astronomy Software). Despite similarity to NOvA, it has nothing to do with it. This is an API to find coordinates of celestial objects using the ephemeris file (DE405 ephemeris, in the trigger the file is named JPLEPH).

The trigger defines few parameters to make track finding more efficient:

• AngleCut: 5 # degrees
  [defines cone around the Moon (Sun) around which we're registering tracks]
• AvgRate: 16 # Hz
  [defines rate the trigger to set to. It's demanded by possibilities of the DAQ system]
• AngularSuppression: 5 # degrees
  [the farther from the center of the cone, the less tracks we register, since the center of the cone contains data of bigger interest for us]
• LengthCut: 150 # cm
  [minimal length of a track]
• BinCut: 10 # number of bins
  [minimal number of bins in a track]

You can find more details of this algorithm and how it was developed in these materials:

• http://nova-docdb.fnal.gov:8080/cgi-bin/ShowDocument?docid=14248
• http://nova-docdb.fnal.gov:8080/cgi-bin/ShowDocument?docid=16606
• http://nova-docdb.fnal.gov:8080/cgi-bin/ShowDocument?docid=16479
• bunch of earlier Moon shadow reports

Moon Shadow Analysis module for pclist files¶

Moon Shadow Analysis module for artdaq files¶