U4. Map generator Date: 23 April 2002 (draft v1) Contributors: S. Digel (SU-HEPL) Function This module constructs binned maps of gamma rays (‘counts’), exposure, and intensity from the output of the Event data extractor (U1) and the Exposure Calculator (U3). Calculations of exposure maps will likely involve interpolation of exposures calculated for the standard tessellation grid. Inputs Coordinate gridding of the maps and coordinate projection. Parameters to be ‘marginalized’ (integrated over) Gridding of the remaining parameters (e.g., energy or inclination angle) Data set produced by the Event data extractor U1 Exposure matrix produced by the Exposure calculator U3 Databases required None Outputs Counts and/or exposure maps (perhaps multidimensional). The intensity map, i.e., the ratio of counts and exposure, can be calculated as well. All output must include (in a header) the specifications of selection criteria used (for the input gamma-ray and exposure datasets) as well as of the parameters marginalized as part of the map generation. Performance Requirements TBD. The map generation is not likely to be computationally intensive. Other Modules Required None. Host Environment: Run on central server or client computer. Existing Counterparts None. The EGRET analogs, MAPGEN (counts maps) and INTMAP (exposure and intensity maps), are based on single viewing periods, Open Issues for Definition or Implementation 1. What coordinate systems should be supported? Systems other than in the photon dataset? 2. What coordinate projections should be supported? 3. Will any analysis tools require as input any of the maps generated here as input? Or will the maps primarily be for visualizations?