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Current issue   Ukr. J. Phys. 2017, Vol. 62, N 7, p.642-649
https://doi.org/10.15407/ujpe62.07.0642    Paper

Savchenko D.O.1, Iakubovskyi D.A.2,1

1 Bogolyubov Institute for Theoretical Physics
(14b, Metrolohichna Str., Kyiv 03143, Ukraine; e-mail: dsavchenko@bitp.kiev.ua)
2 Discovery Center, Niels Bohr Institute
(17, Blegdamsvej, Copenhagen, Denmark)

Towards Robust Detection of a Faint Narrow Line in X-Rays – the Role of Continuum-Induced Systematics

Section: Astrophysics and Cosmology
Original Author's Text: English

Abstract: Some of recent detections of a narrow emission line at ∼3.5 keV have been accompanied by
subsequent non-detections in the same sources, raising discussion about the actual level of sys-
tematic errors. In this paper, we study the systematics caused by an imperfect knowledge of a
continuum model. Our simple theoretical estimate and detailed modeling of simulated spectra
allow us to calculate the value of this “continuum-induced” systematics for the frst time. We
show that, for some objects such as the M31 central part or the Draco dwarf spheroidal galaxy,
the obtained level of systematics within a well-defned continuum model allows one to fully rec-
oncile the controversial results claimed previously by diferent groups of authors. To minimize
the efect of “continuum-induced” systematics, we show that one should reasonably decrease
the size of the spectral bin and increase the modeled energy range.

Key words: X-rays, general line, identifcation of the dark matter.


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