I will try to give the explanation for this, I request you to go throgh this, This thread closes in ONE day.
Originally Posted by snp.gupta
SNP Gupta's ATM idea re the CMB
see post #14 dtd 24-Sept-2007, 05.40 am, by Nereid
Please explain section 7 ("Extragalactic Sources") of the 2003 Bennett paper, "First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Foreground Emission"; in particular, please explain the 208 extragalactic point sources Bennett reports were detected, including the ~5 which the WMAP team expected to be spurious.
You may download the paper, in PDF form (1.7 MB!) from the thread. -Nereid]
Explaining WMAP sources
After question in the BAA, to explain the sources of WMAP, I started to think how to solve it. I decided to check the existing catalogs, instead of checking for new sources.
There are thousands of catalogs. Some star catalogs are not open for public. We have to pay money. Some times it is hundreds and thousands of dollars. Getting money is a problem. After paying money, we may find it is not useful. First we have to pay money to look into catalog. So I started collecting of data about lot many catalogs and all are different, there is no uniformity. Some use Galactic coordinate system, some use J2000, 1950, 1965, 62, 58, etc. Some times, adjacent entries are having different coordinate systems. The paper 2003 WMAP extragalactic point sources Bennett used l &b coordinates. They have not mentioned what coordinate system they used. I took it as Galactic coordinate system, later it was confirmed in their recent 2008 paper on fore ground sources available at the same site. NASA’s HEASARC Browse resulted for some sources, more than three thousand entries, with more than hundred catalogs. The following are criteria for selection of catalogs. As WMAP covers all sky, all sky coverage is important for the catalog. That eliminated many catalogs. This problem became more complicated as all types of catalogs ranging right from Radio to Gamma-ray sources are to be considered. Every catalog writer used his own alignment system.
There are catalog-to-catalog source alignment differences, i.e., the same source was referenced, in different catalogs with different coordinates values. How to do it? Eric Flesch, Wellington, New Zeeland, et al, in their QORGCAT - All-Sky Optical Catalog of Radio/X-Ray Sources did a lot of work in this direction. They matched coordinates of various catalogs in different frequency ranges ranging from Radio to X-rays. They did a lot of VERY, VERY GOOD WORK. That saved me using different catalogs and have REPEATED sources for the same point.
Table 1 gives, all the selected catalogs and the number of WMAP sources it covers in the vicinity of 15-arc min search radius. It is gif file. I will try to get some help for these. These selected catalogs are covering all sky, and total length of Electro magnetic frequency spectrum as to cover for the Blackbody spectrum from one end to another. All the catalogs shown here give the coordinates of sources that send energy in their respective frequency bands. But this does not mean that will be a full blackbody spectrum for some temperature. Basically because, these sources are dynamic in nature, positions are dynamic, powers/ energy outputs are different for different sources. COBE group deducted dynamically foreground signals for compensating, after masking Sun, Moon, planets, and other powerful sources; to get blackbody spectrum. It is simply because our Dynamic universe is having different sources in different frequencies with different strengths. Theoretically sources are required from low frequency end to high frequency end of blackbody spectrum to have signal strength in that area of spectrum. Bigbang predicted CMB not required.
Now I started with getting data about Galaxies, Stars, Radio, Infrared, X-ray, Gamma-ray sources in the vicinity of WMAP sources,. 15 arc min solid angle was taken, centered on WMAP source coordinates. I took 11 arc min for vicinity and 4 arc min for measurement uncertainty, as discussed in the WMAP paper. This 15 arc min is much less than main beam cut-off radii, qR of Radiometer centered on its peak gain direction. By band these radii are K = 2.8°, Ka = 2.5°, Q = 2.2°, V = 1.8°, &W = 1.5°. [ See WMAP sidelobes.pdf , I year results, in the same web site] You can get the Excel file containing All sky catalog of WMAP sources and their optical / x-ray correlations by requesting me. It’s a big file, lets call it as Table 2. Meanwhile I will try to get some help to post it in the forum.
Out of 208 WMAP sources, 7 sources does not have any Radio, Stars, Galaxies, Quasars, etc., with in 15 arc min search radius. This 7 sources are with in the limit of 5 +/- 4 possible spurious sources of WMAP as defined in the paper 2003 . Another 23 WMAP sources require 15 min arc search radius to have some or many astronomical bodies nearby. Remaining all the 178 WMAP sources, have some of these astronomical bodies nearby with in 5 (five only) arc min search radius. All these statistics are from qorg catalog “All-Sky Optical Catalog of Radio/X-Ray Sources.” See table 2 for a detailed listing.
QORGCAT - All-Sky Optical Catalog of Radio/X-Ray Sources
Above sentences are from their catalog introduction. Further details can be taken from the QORG website or HEASARC browse. See QORGCAT in the references list
The Quasars.org (QORG) Catalog is an all-sky optical catalog of radio/X-ray sources. The QORG Catalog aligns and overlays the year 2001/2 releases of the ROSAT HRI, RASS, PSPC and WGA X-ray catalogs, the NVSS (2002), FIRST (2003) and SUMSS (2003) radio catalogs, the Veron QSO catalog (2003) and various galaxy/star reference catalogs onto the optical APM and USNO-A catalogs. This catalog displays calculated percentage probabilities for each optical, radio/X-ray associated object of its likelihood of being a quasar, galaxy, star, or erroneous radio/X-ray association. This table contains the main Master QORG catalog (master.dat) and contains all 501,756 radio/X-ray associated optical objects and known quasars which are optically detected in APM/USNO-A. Up to six radio/X-ray catalog identifications are presented for each optical object, plus any double radio lobes (21,498 of these). These are superimposed (and laterally fitted) onto a 670,925,779-object optical background which combines APM and USNO-A data.
The sources in the WMAP catalog are main-lobe integrations of multi-frequency observations of astronomical bodies and have nothing to do with bright spots in the real sense. They are dependent on the set points provided by foreground radiation elimination software, which subtracts in the name of free-free, power-law synchronous, thermal, dust radiations. They are dependent on levels set up at that particular stage(year) by the software.
X- RAY SENSITIVITY ( THIS IS MY SUPPOSITION ONLY, THIS CAN BE WRONG ALSO, I DON’T HAVE MONEY, OR POWER TO TEST THIS HYPOTHISIS): -
WMAP frequency response of radiometers (dish antennae) in K, Ka, Q, V and W bands is in Microwave region in Earth’s atmosphere. Once WMAP satellite is in vacuum, outside Earth’s atmosphere; it will have some X-ray sensitivity. In Earth’s atmosphere, the X-rays have a range of few feet. But in vacuum, there is no obstruction. It is well known that 1N4001 /1N4008 series diodes are effectively used as X-ray detectors regularly. See Electronic circuits/ Microcircuits / Integrated circuits generally use them. It is not impossible to visualize that some sensor circuit malfunction under X-rays in vacuum outside Earth’s atmosphere in WMAP satellite.