[source, ruby]
----
response = client.search(
  body: {
    query: {
      function_score: {
        gauss: {
          "@timestamp": {
            origin: '2013-09-17',
            scale: '10d',
            offset: '5d',
            decay: 0.5
          }
        }
      }
    }
  }
)
puts response
----
