links
Intro
computing tsys
Type of plots generated
Plots of Tsys
monthly plots

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Intro

    12meter data is often taken with the 25Hz winking cal to help correct for electronic gain variations. This includes

• mapping data
• each strip of the map is a scan that can have the winking cal enabled.
• For xband data there usually multiple freq bands taken with each scan
  
• Pulsar data:
• this typically has a 90 sec cal scan at the beginning of each source with the hardware winking cal enabled.'
• This data is normally at sband.

A set or idl routines checks for any spectral line scans with the winking cal data  (the pulsar data is not currently processed). The routines will:

• search for any spectral line files with winking cal data.
• input the files and compute tsys.
• plot tsys vs  data and elevation.

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Computing tsys:

    To compute tsys the following routines are used:

• masfilelist,masfilesum:
• find all files for a given day
• read the headers for all these files
• only keep files that have hdr.calsrc == 2  (winking cal)
  
• mastsyshwcal: process a set of files.
  
• masgethwcal() input file with hw winking cals
• return spectra
• split calon, caloff, avg each to 1 row (usually 1 sec)
• mascalonoff:input calon,off spectra, compute scaling factor counts to deg K
• average calon,caloff spectra for scan.
  
• compute a mask to exclude rfi channels
• r= calOnAvg/calOffAvg
• rFlat=r/smooth(r, 3%of channels).. divide by a smoothed version. smooth len = nchan*.03
• robust linear fit to rFlat.  exclude any points outside of 3 sigma (rfi)
• Using the mask of good channels,compute the scaling factor counts to deg K
• mascalscl()
  
• convert the caloff spectra to degK and then average over the mask of good channels to get tsys in degK over the band.
  

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What is generated:

    3 sets of plots are made:

•  plot tsys from the last day that had winking cal data
• this lets you see more detail  when plotting vs date.
• plot tsys for the last five days preceding the current date.
• If there is no data for the last 5 days, then it will leave the last 5 days that did have data.'
• plot tsys for the last 30 days before the current date.

At then end of each month all the data from the previous month is included in a set of plots..

    The data is processed from a cron job that phil runs every morning around 3:30 am. It always takes the previous day as the basis for the plots (so you'll have to wait for the next day to see what happens on a particular experiment.)

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Tsys plots:

    Each set of plots contains:

• Page 1: tsys vs date
• Top is polA
• bottom is polB
• Each color is a different freq band.
• any data found is binned into 7 freq bands.
• Page 2: tsys vs elevation
• top: polA
• bottom: polB

• Date with last winking cal data (.ps) (.pdf)
• last 5 days of  data (.ps) (.pdf)
• last 30 days of data (.ps) (.pdf)

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Monthly plots

date (yymm)	plots	notes
2303		nodata
2302		no data
2301	(.ps)   (.pdf)
2212	(.ps)   (.pdf)	has a few tsys measurements, end of dec
2211	(.ps)   (.pdf)
2210		no data
2209	(.ps)   (.pdf)
2208	(.ps)   (.pdf)
2207	(.ps)   (.pdf)
2206	(.ps)   (.pdf)	220627: measured cals with sky,absorber
2205	(.ps)   (.pdf)