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gcnnoticescoreStatistics

Statistics

statistical measures of source significance or classification

View the source on GitHub

Properties

* = required

NameTypeDescription
farnumberFalse alarm rate: the rate of occurrence of non-astrophysical events that are of the same intensity or significance as the current event [Hz]
trigger_typeenumType of trigger algorithm used to identify the transient event.
Options: rate, image
net_count_ratenumberNet count rate of the transient above the background [counts/s] over rate_duration and rate_energy_range. Do specify rate_duration and rate_energy_range with net_count_rate property.
backgound_count_ratenumberCount rate of the background during the transient [counts/s] over same rate_duration and rate_energy_range used for net_count_rate.
rate_snrnumberRate signal to noise ratio [dimensionless]
rate_durationnumberInterval over rate signal to noise ratio calculation [s]
rate_energy_rangearrayLow and High energy bounds used in rate signal to noise ratio calculation, if not parsed in Reporter.schema.json, default unit is keV
image_snrnumberImage signal to noise ratio [dimensionless]
image_durationnumberInterval over image signal to noise ratio calculation [s]
image_energy_rangearrayLow and High energy bounds used in image signal to noise ratio calculation, if not parsed in Reporter.schema.json, default unit is keV
p_astronumberProbability [dimensionless, 0-1] that source is of astrophysical origin
classificationobjectDictionary mapping mutually exclusive source classes to probabilities between 0 and 1, the sum of all values must be 1. e.g. ({'BNS', 0.9}, {'NSBH', 0.05}, {'BBH', 0.05})
propertiesobjectDictionary of binary classifiers, each entry is between 0 and 1. e.g. ({'NS', 0.95}, {'REMNANT', 0.3})

Example

{
  "$schema": "https://gcn.nasa.gov/schema/v4.2.0/gcn/notices/core/Statistics.schema.json",
  "far": 0.001,
  "trigger_type": "rate",
  "net_count_rate": 2000,
  "background_count_rate": 250,
  "rate_snr": 5.2,
  "rate_duration": 10,
  "rate_energy_range": [
    100,
    1000
  ],
  "image_snr": 3.1,
  "image_duration": 30,
  "image_energy_range": [
    50,
    500
  ],
  "p_astro": 0.8,
  "classification": {
    "BNS": 0.9,
    "NSBH": 0.05,
    "BBH": 0.05
  },
  "properties": {
    "NS": 0.95,
    "REMNANT": 0.05
  }
}
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