Source extraction and photometry for the far-infrared and sub-millimeter continuum in the presence of complex backgrounds

Astronomy and Astrophysics – Astrophysics – Galaxy Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Accepted on A&A

Scientific paper

(Abridged) We present a new method for detecting and measuring compact sources in conditions of intense, and highly variable, fore/background. While all most commonly used packages carry out the source detection over the signal image, our proposed method builds from the measured image a "curvature" image by double-differentiation in four different directions. In this way point-like as well as resolved, yet relatively compact, objects are easily revealed while the slower varying fore/background is greatly diminished. Candidate sources are then identified by looking for pixels where the curvature exceeds, in absolute terms, a given threshold; the methodology easily allows us to pinpoint breakpoints in the source brightness profile and then derive reliable guesses for the sources extent. Identified peaks are fit with 2D elliptical Gaussians plus an underlying planar inclined plateau, with mild constraints on size and orientation. Mutually contaminating sources are fit with multiple Gaussians simultaneously using flexible constraints. We ran our method on simulated large-scale fields with 1000 sources of different peak flux overlaid on a realistic realization of diffuse background. We find detection rates in excess of 90% for sources with peak fluxes above the 3-sigma signal noise limit; for about 80% of the sources the recovered peak fluxes are within 30% of their input values.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Source extraction and photometry for the far-infrared and sub-millimeter continuum in the presence of complex backgrounds does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Source extraction and photometry for the far-infrared and sub-millimeter continuum in the presence of complex backgrounds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Source extraction and photometry for the far-infrared and sub-millimeter continuum in the presence of complex backgrounds will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-112465

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.