This interface allows a user to build a list of hours, within any specified time span, when values of any subset of OMNI parameters fall into user-specified numeric ranges. The list may then be used to: create a screen listing of those hours, with the values of any independently specified subset of OMNI parameters; to create an ASCII or XML output file with the same information; or to create an event list having the start and stop hours of intervals where (almost) every hour satisfies the numeric range condition(s). Plots may also be made for an arbitrary set of parameters for any event, or series thereof, of an event list.
To accommodate data gaps and brief deviations from user-specified numeric range(s) during extended event intervals when creating an event list, the interface allows users to specify a maximum number ("max gap duration" in interface) of contiguous hours of non-testability of, or non-adherence to, specified ranges to fall within the start and stop times identified for a given event. The default value of this number is zero. Note that output event lists show, in the column labelled "#hours in gaps," the number of non-tested and non-adhering hours included in each event.
Numeric range conditions (filtering conditions) are specified in the pair of boxes to the right of the name of any desired filtering parameter(s) on the interface page. The subset of parameters to be output in a screen list or file is specified by checking the boxes to the left of the desired parameter names. Relative to event lists, left-side boxes are checked in order to enable the option to make a plot of the checked parameters for any event. (Requests for event lists, with no left-side boxes checked, yield the event lists but without a plot option.) For event lists, the maximum duration of acceptable deviations (cf. previous paragraph) is specified in the box where "Event list" is selected as the desired activity. Time spans for analysis are specified in start and stop boxes, in either YYYYDDD or YYYYMMDD format.
OMNI hourly data are extensively discussed at http://omniweb.gsfc.nasa.gov/html/omni2_doc.html
If you have any questions/comments about this service contact:
Dr. Natalia Papitashvili, Space Physics Data Facility Mail Code 672,
NASA/Goddard Space Flight Center, Greenbelt, MD 20771|