SearchFlux

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This page documents the searchFlux function of Python module analysisUtils.

Searches the ALMA online calibrator catalog at JAO for a specific source name. It returns the recent flux densities and uncertainties, along with the maximum baseline of the configuration (in units of kilolambda) that supplied the measurement. It also returns the RA/Dec position.

Usage

# In CASA
au.searchFlux(sourcename, date='', band=None, fLower=1e9, fUpper=1e12, 
                 tunnel=False, maxrows=10, limit=1000, debug=False, server='', dateCriteria=0, 
                 verbose=True, measurements=None, returnMostRecent=False, 
                 searchAdjacentNames=False, showDateReduced=False, dayWindow=-1)

Required input parameters:

  * sourcename: string, e.g. 'J1924-292' (% is the wildcard character)

Optional input parameters:

  * date: the day to begin the search (default=today). Format = YYYYMMDD, 
          e.g. '20120101' or '2012-01-01' or '2012/01/01'  
          where the delimiter can be any non-integer character
  * fLower, fUpper: optional floating point values in GHz or Hz
  * band: optional band number integer (3..9)
  * tunnel:  Set this to True if you are outside the JAO network and want to
            access a server only accessible from within the JAO network.
            (As of June 14, 2013, this is no longer necessary.)
  * server: special server name to access
  * limit:  the maximum number of rows to return from the server (R9.x)
  * sourceBandLimit:  the maximum number of rows to return from the server (R10.x)
  * maxrows:  the maximum number of rows to display
  * dateCriteria: -1, 0 or 1, meaning: before, on, after (currently, only 0 works!)
  * showDateReduced: show the date of ingestion rather than observation
  * dayWindow: if non-negative, then return a list of all measurements within this
              many days

Returns:

  * The age of the most recent measurement (in days)
  * Unless returnMostRecent = True, in which case it returns a dictionary:
     {'date':'YYYYMMDD', 'frequency'=<float_Hz>, 'flux'=<float_Jy>, 'age': <int_days>}

Examples

# In CASA
CASA <4>: au.searchFlux('J1924-292')
Source:  B1921-293 = J1924-2914 = J1924-292 = J192451-291428
J2000: 19:24:51.05594, -29:14:30.12108 (VLA)
Requested Freq.: 1-1000 GHz , Requested date:  20140418
 Rank | Flux Density (Jy) | YYYY-MM-DD | Meas. Freq | klambda | Source Name    | uvmin-uvmax |
    1 |    5.530 +-  .03  | 2014-04-11 | 103.49 GHz |     0.0 |     J1924-2914 |       |
    2 |    5.630 +-  .02  | 2014-04-11 |  91.46 GHz |     0.0 |     J1924-2914 |       |
    3 |    2.600 +-  .12  | 2014-04-10 | 343.48 GHz |     0.0 |     J1924-2914 |       |
    4 |    2.340 +-  .08  | 2014-04-10 | 343.48 GHz |     0.0 |     J1924-2914 |       |
    5 |    5.530 +-  .32  | 2014-04-03 | 103.49 GHz |     0.0 |     J1924-2914 |       |
    6 |    5.630 +-  .28  | 2014-04-03 |  91.46 GHz |     0.0 |     J1924-2914 |       |
    7 |    5.550 +-  .29  | 2014-03-24 | 103.49 GHz |     0.0 |     J1924-2914 |       |
    8 |    5.620 +-  .22  | 2014-03-24 |  91.46 GHz |     0.0 |     J1924-2914 |       |
    9 |    2.320 +-  .27  | 2014-03-24 | 343.53 GHz |     0.0 |     J1924-2914 |       |
   10 |    5.420 +-  .28  | 2014-03-21 | 103.49 GHz |     0.0 |     J1924-2914 |       |
Found 203 measurements, but truncated because maxrows was set to 10.
Try setting the band (e.g. band=7).
  Out[4]: 28