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Penn Array Demonstration Science Projects

An attempt to flesh out some of the details of what we'll observe in the first season or two.

First, the GBT pointing won't be good during the day at 3mm so we can only observe at night. Where is the sun?

Planets

Saturn: 10h30 or so

0. The Moon?

1. Orion

No brainer target once we think things are working. coordinates: 05h, +10 deg. Good for winter.

Observing Requirements

• Big mosaicked map, with a couple of passes over each 'tile'. Integration time determined by practical considerations (telescope slew speed limits, etc)

2. Pre-protostellar clouds

These are bright and compact but not trivially compact. 3mm observations would test dust models and complement higher frequency continuum maps (as are sensitive to colder dust than the submm). Yancy Shirley has provided a list of good targets that are well studied at other wavelengths:

        GL2591  20 27 35.5      +40 01 13       B1950.0  -- early fall
        S140    22 17 41.1      +63 03 42       B1950.0  -- early fall
        S231    05 35 51.3      +35 44 16       B1950.0  -- winter       (aka G173.49+2.42)

Observing Requirements per target

• 5'x5' map, with an hour or two total integration time, should be fine.

3. BLAST sources/High Z Galaxy fields

• Noise tests are high z galaxy fields. Might as well pick useful ones. Also-- stuff clusters. Find the brightest mm high-z source you can and use it as the center of a daisy scan, for noise tests.
• We will probably need a good submm cross-calibration. Thoughts/targets? Do we need to propose for approximately concurrent JCMT or other observations (note: JCMT deadline for the end of 05 observations, is March 31)
• Many surveys (SHADES, BLAST, IRAM, VLA, Subaru, Chandra, etc) are targeting
  • Lockman Hole (10:52, +57 deg) -- ~ 20' x 20'. Good winter target.
  • Subaru Deep Field South (13:24, +27 deg). Somewhat larger. Good spring target but conflicts with lockman a bit.
• Some of this can be photometry (ie mapping), some measuring already-known sources.

• APM0825+52
• A1835

Observing Requirements

• To get to 15 uJy RMS (a factor of a few above the expected 3mm confusion limit) one needs 6 hours per 5' x 5' patch. Therefore a total of 100 hours per deep field (Lockman hole or Subaru).

4. SZE in Galaxy Cluster s

Fairly small maps of novel, small-scale effects are probably our niche until there is a sweeping tertiary.

• radio/x-ray "ghost" cavities-- do the massive holes in the ICM of some clusters have thermal pressure support or not? See for example Pfrommer, Ensslin, and Sarazin or McNamara et al. ... some specific targets:
  • A2597 (23:25, -12:06) -- fall target
  • Perseus (03:18, +41:30) aka Abell 426 -- winter target. Very strong signal expected. Also has a very bright radio galaxy in the center (3C84) so we are guaranteed some signal, and this may even help with the imaging.

Observing Requirements

• Pfrommer et al predict a few hours with GBT+Penn Array on a 5'x5' field will do Perseus. Their calculation needs to be checked in detail though.

AGNs

Cen A would make a nice image (13h, -42 deg); perhaps also Hydra A, other big jets (IC?)

Nebulae

Rosette, Carina, etc...

from Bill Cotton:

   The following look like possibilities, all a bit less than an arcmin                                                   
and in the right part of the sky.                                                                                         
                                                                                                                          
NGC2346 J 07 09 41    -00 48 56    size ~54"  NVSS  nothing obvious                                                       
NGC2371 J 07 25 34.7  +29 29 25.6  size ~44"  NVSS ~ 60 mJy                                                               
NGC2392 J 07 29 10.77 +20 54 42.5  size ~48"  NVSS ~ 300 mJy                                                              
                                                                                                                          
The last one, the  Eskimo Nebula, is the strongest at 20 cm.                                                              
                                                                                                                                                                                                                                          

5. Thoughts on Calibration (9h, -12 eg)

Primary calibrators

• weak planets like uranus & neptune??
  • Uranus: sep 2005 (22:30, -09 deg; 3.7'' diam). essentially the same in feb 06. Brightness temp ~100 K.
  • Neptune: sep 2005 (21h , -16 deg; 2.3'' diam). ditto. temp ~ 100 K.
• SMA Calibrator list -- unclear absolute scale, but many sources, incl. 3mm fluxes, and date of obs
  • http://sma1.sma.hawaii.edu/callist.html
• SMA Primary Calibrator online modeller -- includes uranus, neptune, some asteroids (for which GBT might need special ephemerides) -- http://sma1.sma.hawaii.edu/planetvis.html

Secondary calibrators, pointing calibrators and general "bright pointlike targets"

• IRAM 30m pointing calibrators (mostly 3mm)
• Valid 3mm pointing calibrators from Jim Condon's "calfind2" program. These sources are known to be compact and have very good positions. The 90 GHz flux densities are extrapolated, sometimes from below 40 GHz, and may not be reliable.
• Here is a list of 3mm measurements of AGN and quasars from the NRAO 12-m, due to Holdaway, Owen, & Rupen
• Ultra-compact HII regions will have flattish spectra from the radio, with dust just starting to contribute at 3mm, and few arcsecond sizes. A good catalog is that of

• Michelle Caler's writeup of BLAST calibrators is attached below
• selected wmap sources -- these are bright and often not terribly extended, and are a reasonable sample of first things to look at. Since many are somewhat extended they are not good for determining pointing offsets. It would be sensible to cross-correlate this list-- reliably bright-- with the Condon list-- reliably compact-- these are our perfect pointing sources and secondary flux calibrators.
  • (13jan06) I have now done this-- here is the Condon and Yin 3mm calibrators correlated with WMAP detections list. The radius for a positive coincidence was taken as 15 arcseconds; positions listed are from Condon and Yin which has 0.5" accuracy.
  • Here are the brightest few sources (by their WMAP 90 GHz fluxes-- these are actually ALL the WMAP 90 GHz detections)

 0808-0751  08:08:15.54  -07:51:09.886   90.00   1.31   121.60  90.00   1.20   0.60 
 2139+1423  21:39:01.31  +14:23:35.991   90.00   0.54   38.10  90.00   1.50   0.80 
 0646+4451  06:46:32.03  +44:51:16.590   90.00   1.31   98.90  90.00   1.70   0.80 
 1512-0905  15:12:50.53  -09:05:59.829   90.00   0.72   130.90  90.00   1.70   0.70 
 1829+4844  18:29:31.78  +48:44:46.161   90.00   0.78   85.90  90.00   1.70   0.40 
 2331-1556  23:31:38.65  -15:56:57.009   90.00   0.60   16.50  90.00   1.90   0.60 
 2134-0153  21:34:10.31  -01:53:17.238   90.00   0.66   36.50  90.00   2.00   0.60 
 1159+2914  11:59:31.83  +29:14:43.826   90.00   1.07   151.80  90.00   2.10   0.60 
 1753+2848  17:53:42.47  +28:48:04.939   90.00   0.60   91.90  90.00   2.20   0.70 
 0457-2324  04:57:03.18  -23:24:52.020   90.00   1.01   75.20  90.00   2.70   0.60 
 0136+4751  01:36:58.59  +47:51:29.100   90.00   0.95   53.20  90.00   2.90   0.70 
 0927+3902  09:27:03.01  +39:02:20.851   90.00   2.03   128.40  90.00   3.10   0.80 
 2232+1143  22:32:36.41  +11:43:50.904   90.00   1.49   25.20  90.00   3.10   0.70 
 1337-1257  13:37:39.78  -12:57:24.693   90.00   4.17   152.00  90.00   3.70   0.70 
  NOTE: 1337-1257 is a z=0.5 QSO with a nearby (possibly coincident) xray source. NVSS image is pointlike
 0423-0120  04:23:15.80  -01:20:33.065   90.00   1.73   65.80  90.00   3.90   1.00 
 1635+3808  16:35:15.49  +38:08:04.500   90.00   1.25   107.20  90.00   4.20   0.70 
   NOTE: 1635+3808 is a z=1.8 QSO. NVSS image is pointlike
 2253+1608  22:53:57.75  +16:08:53.560   90.00   10.20   23.70  90.00   5.90   0.90 

• Jan 2008 -- I attached the OVRO/BIMA/CARMA database of 90 GHz fluxes as a function of time to the bottom of this page.

-- BrianMason - 17 Mar 2005

• second_calib.ps: IRAM 1mm secondary calibrators memo

• blastcal-2.pdf: Michelle Caler's writeup of BLAST calibrators

• bolometerScienceShortMar07.pdf: short bolometer array science review

• cals.fluxes: CARMA 3mm cal flux database

Attachment:	Action:	Size:	Date:	Who:	Comment:
second_calib.ps	action	2324468	11 Sep 2006 - 15:35	BrianMason	IRAM 1mm secondary calibrators memo
blastcal-2.pdf	action	117745	12 Mar 2007 - 15:51	BrianMason	Michelle Caler's writeup of BLAST calibrators
bolometerScienceShortMar07.pdf	action	81321	01 May 2007 - 13:33	BrianMason	short bolometer array science review
cals.fluxes	action	441048	06 Jan 2008 - 18:38	BrianMason	CARMA 3mm cal flux database