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MAST Cross Correlation Help

This page explains how to use the non-catalog-specific features of the MAST cross-correlation pages.

Select one or more missions with which to cross-correlate the selected catalog. (For HST, each instrument is treated as a separate mission.) You can use the Show catalog entries that match any/all of the selected missions selector (see below) to control whether any or all missions have to match a catalog entry in order for that catalog entry's results to be displayed.

Radius (arcmin)
The radius in arcminutes on which to cross-correlate the mission with the object catalog catalog. Each mission has its own independent radius. For each mission, a default radius has been chosen that is more or less appropriate for that mission.

Show catalog entries that match any/all of the selected missions
When you select multiple missions, you can use this selector to control how an catalog row's results will be displayed: Set it to any to show results if the catalog entry cross-correlates with at least one of the selected missions, or set it to all to show only those catalog entries that cross-correlate with every selected mission. For example, you might set this selector to all if you are looking for catalog entries that have been observed with both HST and IUE, or to any to find catalog entries observed with either HST or IUE.

Display n rows per mission
Use this selector to determine how many rows from each mission will be displayed. When ALL is selected, every row found for the mission will be displayed. Optionally, you may use this selector to reduce the number of rows from each mission reported, reducing the length of the results page. The total number of rows for each mission will always be reported.