RUNNING THE ACQUISITION

Status Page

The acquisition of data is controlled from the Midas status page on the web interface. The status page has

  1. An entry for each equipment, i.e. the WFD frontend denoted by WFD01, the CAEN frontend denoted by CAEN, the high voltage frontend denoted by HV, the flight simulator frontend denoted by FS, and the beamline frontend denoted by beamline.The equipment entries indicate the equipment's host machine, the equipment's enabled/disabled status, and provide some statistics on event rates and data rates.Clicking the equipment name gives access to its associated online database entries.

  2. An entry for the event builder, i.e. the process that assembles the data fragments from the CAEN frontend and the WFD frontend into Midas events. The event builder entry indicates the host machine, run/stop status, and statistics on event rates and data rates. The event builder configuration, which specifies the fragments to assemble, is available by clicking on the Chan entry and the Settings entry. Note the event builder automatically figures which segments to assemble based on the enabled/disabled state of the CAEN/WFD frontends.

  3. An entry for the data logger , i.e. the process that stores the Midas events. The data logger indicates the location for logging data, the active/inactive status for logging data, and statistics on writing of events and data.

    To start or stop a run just click the stop/start button at the top left of the status page. The run number, start time and elapsed time are given near the top of the page.

    To turn on/off or otherwise modify the data logging then click the icon for the data logger on the status page. This accesses the ODB sub-directory where logging parameters such as data filenames, event limits, byte limits, etc, are located.