links
Intro
computing tsys
Type of plots
generated
Monthly movies
Intro
Pulsars data is taken daily
with the sband receiver. Up to 10 pulsars are monitored. Prior
to each pulsar observation a 90 second file is taken. This
uses the 25Hz winking cal. The setup is typically:
- 256 freq channels
- 16 bit spectra
- polA,B recorded
- 172.032 MHz bandwidth
- spectra sampling can vary from 32 usecs to 500
usecs.
The cal data files are used to
compute Tsys vs freq.
Computing tsys:
- The 90 second cal file is input. PolA and polB are
processed separately
- Separate calOn,calOff:
- Compute the averages:
- spcCalOnAvg, spcCalOffAvg
- Compute the cal deflection:
- spcCalAvg=spcCalOnAvg - spcCalOffAvg
- Divide spcCalOffAVg/spcCalAvg=spcTsysCalUnits
- this puts the calOff spectra in cal units
- It also removes the IF bandpass
- input the caldegK=cal values vs freq (in degK)
- spcTsysK=spcTsysCalUnits * calDegK
&$
- multiply by the calK(freq) to get tsys in degK
The
latest cal values (measured jun22)
Monthly tsys movies.
- All of the cal files for a month are processed and stored
in an idl save file.
- see x101/12meter/psrsystemp/Readme
- A movie is made with each frame being the tsys Values
computer for a day.
- there are two columns by 3 rows
- left column : polA data
- right column: polB data
- Each color is a different cal file (pulsar)
- Top row: raw average spectra for a day in spectrometer
counts
- middle row: average cal deflection in spectrometer
units
- Bottom Row: Tsys vs freq in degK for each pulsar cal
file
- EL: has the elevation for each observation
- hr: has the ast hor for the start of each
observation
- The plots in the first 2 rows can jump around since the
electronic gain for each cal measurement can change.
- The bottom plots should not vary (unless tsys is
changing)