SUBMILLIMETER NUMBER COUNTS FROM STATISTICAL ANALYSIS OF BLAST MAPS

Journal Article · Sun Dec 20 04:00:00 EST 2009 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/707/2/1750· OSTI ID:21392537

Patanchon, Guillaume ^[1]; Ade, Peter A. R.; Griffin, Matthew; Hargrave, Peter C; Mauskopf, Philip; Moncelsi, Lorenzo; Pascale, Enzo ^[2]; Bock, James J ^[3]; Chapin, Edward L; Halpern, Mark; Marsden, Gaelen; Scott, Douglas ^[4]; Devlin, Mark J; Dicker, Simon R; Klein, Jeff; Rex, Marie ^[5]; Gundersen, Joshua O ^[6]; Hughes, David H ^[7]; Netterfield, Calvin B ^[8]; Olmi, Luca ^[9]

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1. Universite Paris Diderot, Laboratoire APC, 10, rue Alice Domon et Leonie Duquet 75205 Paris (France)
2. Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada)
3. School of Physics and Astronomy, Cardiff University, 5 The Parade, Cardiff, CF24 3AA (United Kingdom)
4. Jet Propulsion Laboratory, Pasadena, CA 91109-8099 (United States)
5. Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States)
6. Department of Physics, University of Miami, 1320 Campo Sano Drive, Coral Gables, FL 33146 (United States)
7. Instituto Nacional de AstrofIsica Optica y Electronica (INAOE), Aptdo. Postal 51 y 72000 Puebla (Mexico)
8. Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street Toronto, ON M5S 3H4 (Canada)
9. Physics Department, University of Puerto Rico, Rio Piedras Campus, P.O. Box 23343, UPR Station, San Juan (Puerto Rico)

We describe the application of a statistical method to estimate submillimeter galaxy number counts from confusion-limited observations by the Balloon-borne Large Aperture Submillimeter Telescope (BLAST). Our method is based on a maximum likelihood fit to the pixel histogram, sometimes called 'P(D)', an approach which has been used before to probe faint counts, the difference being that here we advocate its use even for sources with relatively high signal-to-noise ratios. This method has an advantage over standard techniques of source extraction in providing an unbiased estimate of the counts from the bright end down to flux densities well below the confusion limit. We specifically analyze BLAST observations of a roughly 10 deg{sup 2} map centered on the Great Observatories Origins Deep Survey South field. We provide estimates of number counts at the three BLAST wavelengths 250, 350, and 500 mum; instead of counting sources in flux bins we estimate the counts at several flux density nodes connected with power laws. We observe a generally very steep slope for the counts of about -3.7 at 250 mum, and -4.5 at 350 and 500 mum, over the range approx0.02-0.5 Jy, breaking to a shallower slope below about 0.015 Jy at all three wavelengths. We also describe how to estimate the uncertainties and correlations in this method so that the results can be used for model-fitting. This method should be well suited for analysis of data from the Herschel satellite.

• OSTI ID: 21392537
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 707; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
AIRCRAFT
APERTURES
BALLOONS
COSMOLOGY
DATA ANALYSIS
DIMENSIONLESS NUMBERS
EXPLOSIONS
FLUX DENSITY
GALAXIES
MAPS
MATHEMATICAL SOLUTIONS
MATHEMATICS
MAXIMUM-LIKELIHOOD FIT
NUMERICAL SOLUTION
OPENINGS
SATELLITES
SIGNAL-TO-NOISE RATIO
STATISTICS
TELESCOPES
WAVELENGTHS