Observing time estimates


The time estimate includes time spent on the reference position (Position and Beam Switching) or the reference phase (Frequency Switching) excluding overheads. Add 15% on top of the calculated time for calibrations, pointing, antenna slewing and data handling. Projects requiring frequent frequency changes of the SIS-receiver should allow 15 minutes for each tuning. Frequency changes within each of the three HEMT receiver bands are instantaneous; OSO staff members are required to change between bands. Such changes take about 30 minutes and are done daytime.
      Note that the default temperature scale is in T*A units. To use the main beam brightness temperature scale (TMB) enter the required sensitivity divided by the main beam efficiency.
      Simultaneous observations of two polarisation components are possible for all receiver bands except the range 26-36 GHz (LCP/RCP for HEMT bands, H/V for the 3mm band). Note that the calculated time applies to a single polarisation, i.e., divide the calculated time by a factor of 2 if two polarisation channels can be co-averaged in the data analysis (e.g. if the sought signal is unpolarised).

A mean receiver temperature of 60 K has been adopted across the band for the 3 mm receiver.


PropertyValueUnitDescription
PSW-Position Switching
FSW-Frequency Switching
BSW-Beam Switching
Frequency[GHz]Line frequency
Resolution[kHz]Frequency resolution
Elevation[deg]Typical elevation
Sensitivity[K]Sensitivity (r.m.s.)
Submit values-Calculates the observation time