Differences between revisions 10 and 11
Revision 10 as of 2013-06-19 15:05:21
Size: 2456
Comment:
Revision 11 as of 2013-06-21 09:06:57
Size: 3134
Comment:
Deletions are marked like this. Additions are marked like this.
Line 4: Line 4:
 This is a preliminary photometric analysis of a sample of scans obtained during the last hours of run. The opacity went down at that time. The beam came close to the diffraction limit. The offline processing software has been largely tested on Run5 and has been quickly fixed to adapt to the new Lissajous scans on point sources. The taumeter is used for opacity correction with a nu^2 scaling between the 1.2 and 2.1mm channels (soon to be updated with the NIKAtau).  (19/06/2013) This is a preliminary photometric analysis of a sample of scans obtained during the last hours of run. The opacity went down at that time. The beam came close to the diffraction limit. The offline processing software has been largely tested on Run5 and has been quickly fixed to adapt to the new Lissajous scans on point sources. The taumeter is used for opacity correction with a nu^2 scaling between the 1.2 and 2.1mm channels (soon to be updated with the NIKAtau).
 (21/06/2013) Update the post with noise measurement on a weak source
Line 39: Line 40:
Noise on weak sources by tomorrow. == Point-source noise measurement ==
Several scans were done on the faint point source HFLS3, discovered by Riechers et al Nature, 2013, at the redshift of z=6.337, with these fluxes: S240GHz=15+-0.2mJy, S140=3.2+0.12 PdBI. I selected only 3 Lissajous scans of 5 minutes each (the others may have problems due to the 1mm tuning sensitivity at low opacity): 20, 25, 26 on 20130618. The maps are there (no smoothing, pixel size = 3 arcsec, contours at 1, 2, 3 sigma):
|| {{attachment:AllMapRadec_HFLS3_20130618_20_26.jpg|HFLS3 1.2 mm|width=500}} || {{attachment:AllPlotRadec_HFLS3_20130618_20_26.jpg|HFLS3 2.1 mm|width=500}} ||

Short photometric analysis of the last night of observations (FXD)

Goals

  • (19/06/2013) This is a preliminary photometric analysis of a sample of scans obtained during the last hours of run. The opacity went down at that time. The beam came close to the diffraction limit. The offline processing software has been largely tested on Run5 and has been quickly fixed to adapt to the new Lissajous scans on point sources. The taumeter is used for opacity correction with a nu^2 scaling between the 1.2 and 2.1mm channels (soon to be updated with the NIKAtau). (21/06/2013) Update the post with noise measurement on a weak source

NIKA observations

  • Day: 18/06/2013

  • Scans: Lissajous of 5 min on secondary calibrators and otfgeom (12min) for Uranus

  • Size of the Lissajous pattern: 90"x90"

  • Size of the map: 180"x180"

  • Opacity at 225 GHz: 0.2 (0.4 for Uranus otfgeom)

  • Elevation of the sources: 40-60 deg

First the primary calibrator Uranus is set at 47.2 and 16.4 Jy.

  • Uranus 1.2 mm

    Uranus 2.1 mm

We observe each source at both wavelengths, shown on the maps given below. Contours are at 1,2,3,4,6,8,10 and 12 sigma.

* First we start with a quasar (a true point-source) : 3C345

  • 3C345 1.2mm

    3C345 2.1mm

* Then here are 3 secondary calibrators

  • MWC349 1.2 mm

    MWC349 2.1 mm

    NGC7538 1.2 mm

    NGC7538 2.1 mm

    W3(OH) 1.2 mm

    W3(OH) 2.1 mm

* Notice the second source in the NGC7538 field. A discovery? Notice some extended weak features too in other fields.

Fluxes for 3C345 are 1.9579 +- 0.0053, 2.7098 +- 0.0016 Jy (at 1.2 and 2.1 mm)

Fluxes for MWC349 are found as : 1.8551 +- 0.0064, 1.6512 +- 0.0019 Jy

Fluxes are for NGC7538: 9.1976 +- 0.0097, 4.6906 +- 0.0029 Jy

Fluxes are for W3(OH): 10.8917 +- 0.0091, 5.4545 +- 0.0022 Jy

Point-source noise measurement

Several scans were done on the faint point source HFLS3, discovered by Riechers et al Nature, 2013, at the redshift of z=6.337, with these fluxes: S240GHz=15+-0.2mJy, S140=3.2+0.12 PdBI. I selected only 3 Lissajous scans of 5 minutes each (the others may have problems due to the 1mm tuning sensitivity at low opacity): 20, 25, 26 on 20130618. The maps are there (no smoothing, pixel size = 3 arcsec, contours at 1, 2, 3 sigma):

HFLS3 1.2 mm

HFLS3 2.1 mm

18Jun2013 (last edited 2013-06-26 09:43:05 by NikaBolometer)