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Variability analysis in low count rate sourcesA method, based on the chi-square statistics, is described for detecting pulselike time variability in low count rate sources observed with photon-counting instruments. This method can be used even in the presence of observational gaps, takes full advantage of the filtering effect due to binning with different bin sizes, and takes into account the arbitrariness introduced by the binning phase. The procedure developed to limit the dependence of the results on the binning phase and ensure statistically correct results is described along with the application of the proposed procedure to a model of a variable source. Monte Carlo simulations are used to show how the method can be used to derive the characteristic variability time scales and that the method is more sensitive than the nonparametric Kolmogorov-Smirnov test in detecting variability to a given confidence level.
Document ID
19870051106
Acquisition Source
Legacy CDMS
Document Type
Reprint (Version printed in journal)
External Source(s)
Authors
Collura, A.
(CNR Istituto per le Applicazioni Interdisciplinari della Fisica, Palermo, Italy)
Maggio, A.
(Consiglio Nazionale delle Ricerche Palermo, Italy)
Sciortino, S.
(Consiglio Nazionale delle Ricerche Palermo, Italy)
Serio, S.
(Consiglio Nazionale delle Ricerche Palermo, Italy)
Vaiana, G. S.
(Osservatorio Astronomico Palermo, Italy)
Date Acquired
August 13, 2013
Publication Date
April 1, 1987
Publication Information
Publication: Astrophysical Journal, Part 1
Volume: 315
ISSN: 0004-637X
Subject Category
Astrophysics
Accession Number
87A38380
Funding Number(s)
CONTRACT_GRANT: NAG8-445
CONTRACT_GRANT: NAS8-30751
Distribution Limits
Public
Copyright
Other

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