SNODB Viewer Window

The SNODB Viewer window provides an interface for using the event display to view certain parameters derived from the SNODB.

The SNODB Server field specifies the IP address of the computer running the QSNODB program, or "localhost" if running on the same computer as XSNOED. The QSNODB program must be running for the SNODB Viewer to function.

The first Date and Time fields specify the time of the parameter to be loaded using the Load (1) button. The second date/time fields must also be completed to take a difference using the Diff (1-2) button. The formats are YYYYMMDD for the date, and HHMMSSCC for the time (CC is centiseconds). Times are specified in UTC.

The Raw Data Value specifies the hardware ADC value that is used for calculating calibrated times and charges. By default, the TAC value is set to 2250 (which roughly corresponds to the peak in the timing distribution), and the charge values are set to 620 (which roughly corresponds to one PE).

CMOS Cell Num gives the hardware CMOS cell number for the constants to be loaded, and must be in the range 0 to 15.

The loaded Parameter can be selected from a pop-up menu containing the following entries:

• Calibrated Times - Loads the ECA time calibrated TAC data for the specified raw data value. (No time walk applied.)
• Calibrated Charges - Loads the pedestal-corrected QHS, QHL and QLX data for the specified raw data value.
• Charge Pedestals - Loads the QHS, QHL and QLX charge pedestals.

Press Load (1) to load the selected parameter for the first date/time, or Diff (1-2) to calculate the difference in the parameters between the two specified times. The derived values are loaded into the "precalibrated" data for the event, so Data/Precalibrated must be selected from the menus to view the results. (This is done automatically when the data is loaded.) Pressing Done closes the SNODB Viewer window.