VLA calibrator information for 0837+2454

This page summarizes the information for 0837+2454 as found in the original VLA calibrator list and, if found there, a link to search the NRAO VLA Archive Survey (NVAS) for calibrator data before 2010. Furthermore, a table with the most recent approximate flux densities, starting from 2017 as mined from the VLA CASA pipeline is presented.

If shown at the top, we have recovered the original, pre-WIDAR ANTSOL flux density solutions from the period roughly 2000-2007; symbols as explained next.
The mined data are plotted (gray, on the left hand side) as function of (log) frequency on the top and as function of time on the bottom. The frequency band symbols in the bottom panel follow the symbols as outlined in the top panel:

4-band  (~75 MHz) horizontal stripe       X-band (~10.0 GHz) cross
P-band (~350 MHz) open triangle        U/Ku-band (~15.0 GHz) filled square
L-band (~1.5 GHz) VLA-Y shape             K-band (~22.2 GHz) open circle
S-band (~3.0 GHz) filled triangle      A/Ka-band (~33.2 GHz) 6-pointed star
C-band (~6.0 GHz) open square             Q-band (~45.0 GHz) filled circle
Assume a 10% flux density error on each point, up to 30% for the higher frequency data points. The dashed lines in the frequency plot indicate the approximate spectral index in the frequency band (tied to the measured flux density).
Depending on the spectral behavior, different receiver observing bands (as indicated with the log-frequency axis) may have very different typical flux densities. Note that there can be significant flux density changes for different array configurations, which start date is indicated at the top of the time-line figure. Calendar years are separated by vertical dotted lines.
If shown, a curve depicts a fit to the (unweighted) average data for each band (if there are more than two bands with measured flux densities). The fit equation is listed at the top where the x-coordinate represents the base-10 log of the frequency (GHz) and the y-coordinate represents the base-10 log of the flux density (mJy/bm). The fit may use more data than shown and is using data with different time stamps, which means typically different flux densitities in a single band for genuine variable sources (and/or observed in different array configurations).
Depending on the variability of the source, array configuration and the quality of the data, this fit may, or may not, be representative for the data!

(Click on the figure for a larger view in a new tab/window)

Original (outdated) VLA calibrator list information:
 IAU NAME EQUINOX  PC RA(hh,mm,ss)    DEC(ddd,mm,ss)   POS.REF ALT.NAME
 ===================================================================
 0837+249   J2000  A 08h37m40.245676s  24d54'23.121600"  Aug01         
 0834+250   B1950  A 08h34m42.314400s  25d04'54.328000"
 -----------------------------------------------------
 BAND        A B C D    FLUX(Jy)    UVMIN(kL)  UVMAX(kL)
 =====================================================
  20cm    L  S S S X       0.60            6
   6cm    C  S S S S       0.60
 3.7cm    X  P P P P       0.52
   2cm    U  S S S S       0.40
 0.7cm    Q  W W W W       0.49

Default NVAS search around this position (in new tab/window)

Results from CASA pipeline flux density mining:
Observing date (UT)Flux density (Jy/bm)Source name used
L-band data ("VLA Y-arm" symbols)
201909170.407J0837+2454
201910040.439J0837+2454
S-band data (filled triangles)
201910040.578J0837+2454
C-band data (open squares)
202101190.475J0837+2454
202205230.383J0837+2454
X-band data (X-crosses)
201802190.671J0837+2454
201908160.501J0837+2454
202007010.466J0837+2454
202109040.371J0837+2454
202110180.377J0837+2454
202208060.391J0837+2454
U-band data (filled squares)
202101110.368J0837+2454