VLBA Calibrator Survey for observing remaining flat-spectrum sources (VCS11)


We propose here VLBA observations to complete two large VLBA surveys to search for gravitational lens candidates based on multiple compact components that we can then follow up with VLBA observations to verify or disprove any candidate lenses, which we will use to test cold dark matter (CDM) versus alternative dark matter models. The observations we propose are:
The target source list consists of 1929 objects.

These two samples complement one another since the CLASS sample is statistically complete down to 50 mJy at 8.4 GHz, while the CRATES sample selects for compact flat spectrum objects.

The main goal of the problem is to find gravitational lenses at scales less than 200~mas what will impose important upper limits on the numbers of mass condensations with high enough central densities to produce strong lensing, which would place interesting limits on various dark matter candidates, such as black holes and some important exotic particle models.


The list of observed sources.

Status on 2021.02.12
The total number of sources observed: 3313
The number calibrator sources processed: 305
The number target sources processed: 3008
The number of segments observed: 18
The number of segments correlated: 18
The number of segments with preliminary solution: 18
The number of segments imaged: 1
The number images 483
The number of target sources detected at C band: 2298
The number of target sources detected at X band: 2080
The number of target sources detected at both bands: 2298
Detection rate: 76%
Nominal campaign duration: 112.25 hours
On source time: 64.3 hours

<-- The catalogue of positions of 2280 target sources from C-band observations: vcs11_c.sou
The catalogue of positions of 2080 target sources from X-band observations: vcs11_x.sou
The catalogue of positions of 2074 target sources from dual-band C/X observations: vcs11_xc.sou

The list of 710 sources were observed, but not detected at C-band
The list of 510 sources were observed, but not detected at X-band
The list of 578 sources were observed, but not detected at both bands simultaneosly
483 images of observed sources are available. -->

Change Log

  1. 2021.03.16 Preliminary analysis of BR235R. The last segment.

  2. 2021.03.15 Preliminary analysis of BR235Q.

  3. 2021.03.09 Preliminary analysis of BR235M, BR235N, BR235O, BR235P.

  4. 2021.02.16 The last segment was observed

  5. 2021.01.11 Processed segement BG235J, BR235K, BR235L

  6. 2020.12.19 Processed segement BG235G, BR235H, BR235I

  7. 2020.12.02 Processed segement BG235F

  8. 2020.11.22 BR235A was imaged.

  9. 2020.11.21 Processed all segments BR235A through BR235E

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This web page was prepared by Leonid Petrov ()
Last update: 2021.03.17_10:11:13