4.2.1 Raw data

When a file in the MB-Fits format is read into BoA, the data from a complete scan are stored in the following attributes of the current DataEntity object:

• FITS_Header: this is a dictionary, which contains some general descriptive parameters for the scan. This includes: telescope name and location, scan type and global parameters, wobbler mode and parameters, source name, coordinates and date of observation, frontend-backend combination in use.
• Data_Obs: the raw bolometer data (or counts) are stored in a 2-dimensional array (integrations $\times$ bolometers).
• Array parameters: the receiver channel parameters are stored in two attributes: Array_Gain (relative gains), and Array_Geo (offsets with respect to the reference bolometer).
• LST: local apparent sidereal time at integration midpoint.
• Az, El: azimuth and elevation actually observed, including pointing corrections and wobbler offsets.
• Lon, Lat: longitude and latitude offsets from the source in user native frame (intermediate coordinates).
• Wobbler_Sta: indicates the wobbler status for each integration point. In case of wobbler switching observations, this is a succession of 'ON' and 'OFF'.
• Subscan_Num, Subscan_Epo, Subscan_Time: when a scan is composed of several observations (or subscans), these arrays contain, respectively: an increasing sequence of integers, the calendar date (floating value in years) of the observation start, and the local sidereal time (in seconds) at observation start.
• Track_Az, Track_El: tracking errors in Azimuth and Elevation (not implemented yet).