Notes for SAM45 spectrometer data on NEWSTAR
The maximum number of frequency channels handled by NEWSTAR is 2048 by default, but SAM45 spectrometer outputs 4096 channels.
In order to process the new data, we have added new functions to the existing NEWSTAR.
Last update : 22April 2011
- Basis: The data will be reduced to 2048 channels either by
(a) a 2-channel binning or
(b) by selecting half of the spectral output.
Both of these options are available in Newstar.
- On "File Services" and "File List" (FLAG(FLAG3) and LINTG(LING2)), you can identify the SAM45 raw data from the "*" tagged at the end of each line.
- When you select the raw data from SAM45 (i.e. files that have "*"), the binning toggle and the channel clipping sliders become available (Figure 1).
- When you select "Binning=2", the data will be averaged every two channels.
- When you select "Binning=1", you have to select the center channel (and the corresponding channel range is shown in the bottom) where you want the data to be clipped.
- On FLAG, the clipping or binning effects only for spectra to display.
- You can select arrays by toggles named "A" on the panel (where it says "AC/SAM" in the "Array" section).
Note : The RMS calculation is performed using the specified RMS range, but multiplied by a factor of two for SAM45 data.
This is because AC45 has 1024 channels, whereas SAM45 has twice as many channels as default.
Figure 1 : File-List window
Nobeyama Radio Observatory