SUN/255.2

Starlink Project
Starlink User Note 255.2

D.S. Berry

9th April 2020


CUPID – A 3D Clump Identification and Analysis Package

Version 2.6

Users’ Manual



Abstract

CUPID provides a set of commands that identfy and analyse clumps of emission within 1-, 2- and 3- dimensional data arrays.

Contents

1 Introduction
 1.1 Available Commands
2 Clump Identification Algorithms
 2.1 FellWalker
 2.2 GaussClumps
 2.3 ClumpFind
  2.3.1 Comparing CUPID ClumpFind with other Implementations
 2.4 Reinhold
  2.4.1 Identifying the Clump Edges
  2.4.2 Cleaning the Clump Edges
  2.4.3 Filling the Clump Edges
  2.4.4 Cleaning up the Filled Clumps
3 Examining the Results
 3.1 2D Data
 3.2 3D Data
 3.3 Using the output Catalogue
4 Taking Account of Varying Noise Levels
A Description of the CUPID applications
CLUMPINFO – Obtain information about one or more previously identified clumps
CUPIDHELP – Display information about CUPID
EXTRACTCLUMPS – Extract previously identified clumps of emission from an NDF
FINDBACK – Estimate the background in an NDF by removing small scale structure
FINDCLUMPS – Identify clumps of emission within a 1, 2 or 3 dimensional NDF
MAKECLUMPS – Create simulated data containing clumps and noise
OUTLINECLUMP – Draw an outline around a 2-dimensional clump identified by CUPID