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 4. Deep survey
The idea is to cover a field with 1mJy rms sensitivity at 1mm and 0.5mJy at 2mm, this is about one hour per
camera FOV (about one arcmin^2). Map should be 4x4 arcmin. Exact field to be decided.
 4. Deep survey: The idea is to cover a field with 1mJy rms sensitivity at 1mm and 0.5mJy at 2mm, this is about one hour per camera FOV (about one arcmin^2). Map should be 4x4 arcmin. Exact field to be decided.

Informations useful for the observations: List of astronomical Target, Pako scripts, Observing strategies

List of Astronomical Target for Nika End 2012 run5

FXD: First version for planets (14/06/2012)

v2 (2/10/2012) prepare Thursday teleconf

Back to the NIKA run5 page

1. Planets Mars, Uranus, Neptune for photometric calibration (primary calibrators)

Name

Right Ascension

Declination

Size (arcsecond diameter)

Flux @ 1.25 mm

Flux @ 2.05 mm

MARS

18:19:04.1164

-24:29:49.029

4.41*4.38

132.072 Jy

45.448 Jy

URANUS

00:18:45.6410

01:14:00.476

3.59*3.49

51.637 Jy

17.897 Jy

NEPTUNE

22:10:45.6241

-11:54:23.087

2.23*2.18

18.926 Jy

6.566 Jy

Here are the ephemeris for the planets

2. Usual bright quasars

  • for image quality and linearity checks

Pointing quasars

3. Strong Galactic sources

  • for secondary calibration and science

Strong galactic sources

4. Weak Galactic sources

  • for photometric calibration checks (secondary calibrators)

Weak galactic sources

5. External extended galaxies

  • for Science demonstration (mapping)

Nearby galaxies

6. High redshift sources

  • for Science demonstration (sensitivity)

Distant galaxies

7. Deep survey and SZ sources

  • for Science demonstration (sensitivity)

Deep survey and cluster of galaxies

Here is the full detailed formatted list Full list with fluxes

Here is the catalog for Pako NIKA2012N5v1.1.sou.txt has to be RENAMED to NIKA.sou on the pako computer (Done 5/11/2012)

Here is a list of IRAM pointing sources with fluxes at 3mm and 2mm (I miss fluxes at 1mm, SL) FluxForPointingSources


Interface with the telescope: Pako

Here is a short manual on useful "Pako for Nika" commands Pako_helpv11.txt

Here is a collection of Pako scripts to gain time and have a reference on the observations we will do (to use them rename the files without the .txt, 2nd version updated with slower mapping speed to minimize tracking errors, 3rd version include pako line continuation sign (-)):

nini.pako => run the initial series of commands that always have to be run at the beginning of an observing session (TBW the first day).

ListAstroTargetNika3/OTF_pointing.pako => OTFMAP 100"x84" in 22 subscan x 10 s = 4+1 ~= 5 min (10"/s) with 2.6 samples (subscan step) per convolved 1mm HPBW (for pointing & focus). 10s = minimum subscan time possible (Pako doesn't authorizes less), hence the choice of subscan length. Scan height changed from 60" to 92" to have more margins for the useful pixels.

ListAstroTargetNika3/OTF_geometry.pako => OTFMAP 300"x220" in 56 subscan x 20 s = 19+3 ~= 22 min (15"/s) with 2.6 samples (subscan step) per convolved 1mm HPBW (for the array geometry = pixels map in sky)

ListAstroTargetNika3/OTF_ps.pako => OTFMAP 140"x90" in 19 subscan x 14 s = 4+1 ~= 5 min (10"/s) with 2 sample (subscan step) per convolved 1mm HPBW (for point source observations)

ListAstroTargetNika3/OTF_2x2.pako => OTFMAP 120"x120" in 25 subscan x 12 s = 5+1 ~= 6 min (10"/s) with 2 samples (subscan step) per convolved 1mm HPBW (for extended source < 2')

ListAstroTargetNika3/OTF_5x5.pako => OTFMAP 300"x300" in 51 subscan x 20 s = 17+3 ~= 20 min (15"/s) with 1.7 samples (subscan step) per convolved 1mm HPBW (for extended source < 5')

ListAstroTargetNika3/OTF_10x10.pako => OTFMAP 600"x600" in 41 subscan x 30 s = 20+4 ~= 24 min (20"/s) with 0.7 samples (subscan step) per convolved 1mm HPBW (for very extended source < 10')

ListAstroTargetNika3/OTF_faint_source.pako => OTFMAP 120"x80" in 21 subscan x 12 s = 4.2+0.8 ~= 5 min (10"/s) with 2.6 samples (subscan step) per convolved 1mm HPBW (for faint sources)

ListAstroTargetNika3/OTF_deep_field.pako => OTFMAP 360"x360" in 61 subscan x 20 s = 20+4 ~= 24 min (18"/s) with 1.7 samples (subscan step) per convolved 1mm HPBW (for faint sources)

ListAstroTargetNika3/OTF_sz.pako => OTFMAP 360"x240" in 41 subscan x 20 s = 14+3 ~= 17 min (18"/s) with 1.7 samples (subscan step) per convolved 1mm HPBW (for faint sources)

ListAstroTargetNika3/OTF_moon.pako => OTFMAP 2000x 2000 in 34 subscan x 40 s = 23+3 ~= 26 min with 0.17 samples (subscan step = 60) per convolved 1mm HPBW (to look at the moon in bad weather)

Here's an excel sheet which helps to find the best focus thanks to a 2nd order polynomial line trend fitting on beam width and amplitude (note that amplitude is much more robust):

Full focus Excel only,

Best focus with basic 2nd order polynomial


Status of observations

spread sheet of sources with integrated time


Observing procedures, strategies for performance verification and debugging

  • v1 starting from discussions between FXD, RZ, NP & SL on 30/5/2012 v2 2/10/2012 elaborate on results from previous runs

  • Use the NIKA pointing model as the starting reference, setting Nasmyth offsets to 0. (NIKA pointing model is close to EMIR one)
  • Do a "classical" POINTING (cross)
  • Implement Nasmyth correction to point on a chosen central pixel
  • Check with POINTING
  • 1st crude Focus: FOCUS sequence
  • 1st OTF-GEOMETRY (scan width = baseline x 2 + FOV + max pointing error = 1x2 + 2.5 + 1 + 0.5 = 5')
  • OTF-GEOMETRY for different foci => focus characteristics for all pixels

  • 1st OTF pointing session (as many quasars as possible in the 8 h slot, probably ~20 ?) => define the NIKA pointing model (20 is not enough stat for a clear determination, but should be OK at 1st order)

  • test skydip going at high airmass values (at least 3)
  • observe typical calibrators 1-20 Jy (e.g. OJ)
  • observe known fainter sources (e.g. Tau sources)
  • redo this procedure the next day

Note: good focus depend on geometry which depend on focus ==> iterative process.

How to find the elevation axis with the observation ? This is degenerate with the pointing model => Iterative approach => accumulate statistics. Due to the degeneracy one as to make a choice on the strategy for the definition of the center of rotation of the array (rotation with elevation of the sky image). After discussions the next days: at the start of the run we will choose the best of the 4 pixels at the center of the array and define it as the center for the pointing model.

For skydips: for each subscan, a calibration is done in order to find the central frequency of each kid

IMBFITS format: keep same structure as before run (e.g. with a fixed number of pixels close to the maximum available, not a varying number of pixels)

Strategy to investigate the Plateau

Since we see the plateau on 31/05/2012 pointing scans with crosses patterns, we will use these fast scans to investigate the plateau, the width should be larger than the plateau itself, that is to say bigger than the array with margins ==> 3 arcmin widths.

Here we will use Uranus, which is fainter than Mars and should yield a representative plateau for fainter sources. We will try crosses with different setting

  • Limit the total power in the acquisition line: play with 2 different values of the DAC => at least 2 scans

  • Limit the number of tones generated (e.g. probe all pixels, or only one which means generating only one tone, or only one part of the array) => at least 2 scans

In any case, scatter off-resonance tones across the frequency range of both arrays.

This should allow us to determine whether the plateau is a pure electronic effect, and have ideas on what causes it.

Sensitivity optimization

In order to measure the sensitivity, we should just make small OTF on Neptune (or a bright quasar or MWC349) for calibration then a the same on an empty field for noise measurement. Repeat this sequence with different settings.

  • Power on kids
  • Delta f (maybe?)
  • One day, stabilize at 200 mK to measure the sensitivity of the arrays (2mm array should be better).

Need for a correct focal plane geometry

Science demonstration requirement

We want to show typical science demonstration data in five areas where we can compare our results with previous (Mambo, Laboca, JCMT, Bolocam) bolometer array results. We have about 16 hours for 7 days. Taking out 5 hours for calibration (calibration on planets and secondary calibrators, pointing, focus, skydip), we are left with 11x7=77 hours of science scans, which we spread this way, with the sources in order of priority:

  1. Dense Galactic regions (15h)
  2. Extended galaxies (12h) M82, M87, CygA, NGC1068,
  3. Faint sources (14h)
  4. Deep survey (16h)
  5. Clusters of galaxies (20h)

Here is a priority list of targets (see the complete list above).

  1. Galactic regions, From brighter to fainter
    • 1.1. Large map of OrionLBS23SM 1.2. Large map of DR21 1.3. Large map of Crab, CasA 1.4. Map of NGC2023 1.5. Map of the horsehead
  2. Extended galaxies
    • 2.1. M82 2.2. NGC1068 2.3. M87 2.4. CygA 2.5. NGC3690 2.6. NGC891
  3. Faint point sources
    • 3.1. Galactic faint sources 3.2. high redshift objects starting with 10 mJy sources at 1mm:
      • Arp220, 4C05.19, APM08279+5255, HSO_ID017, HSO_ID081, HSO_ID011, HSO_ID130, F10214+4724, HLSW01, BR1202-0725, BRI1335-0417, SBS1408+567, H1413+517, MM18423, SMMJ2135
  4. Deep survey: The idea is to cover a field with 1mJy rms sensitivity at 1mm and 0.5mJy at 2mm, this is about one hour per camera FOV (about one arcmin^2). Map should be 4x4 arcmin. Exact field to be decided.
  5. Clusters of galaxies

Priority is on detection

  • 5.1. RXJ1347-1145 (6h) 5.2. A665 (7h) 5.3. MACS0717 or MS0451 (7h)

In case of a strong and not-understood plateau, the mapping of high-contrast extended targets should be limited. The search for point-sources should be reinforced.

ListOfAstroTarget2012N5 (last edited 2013-02-06 13:30:15 by NikaBolometer)