New constraints on the cosmic mid-infrared background using TeV gamma-ray astronomy
C. Renault, A. Barrau, G. Lagache, J. L. Puget;
AaA, 2001, 371, 771
ABSTRACT:Very high energy gamma-ray data obtained by CAT and HEGRA from the active galactic nucleus Mkn 501 are used to constrain the cosmic Mid-Infrared
background.
While the entire infrared and submillimeter spectrum shape based on models
has been fixed and the density scaled as a whole in previous studies, recent
measures on the low and high energy infrared background are extensively used in
this paper.
In this original approach the infrared distribution is only
varied in the unexplored 3.5-100 mu m region.
With a conservative hypothesis
on the intrinsic spectrum of Mkn 501, an upper limit of 4.7 nW
m-2 sr-1 between 5 and 15 mu m is derived, which is very close to
the lower limit inferred from deep ISOCAM cosmological surveys at 15 mu
m.
This result is shown to be independent of the exact density of the lambda <
3.5 mu m and lambda > 100 mu m infrared distribution within the
uncertainties of the measurements.
Moreover, the study presented here rules out a
complete extragalactic origin for the 60 micron tentative background
detection as found by Finkbeiner et al.
(\cite{finkbeiner}).
KEYWORDS: diffuse radiation, infrared: general, gamma-rays: observations, bl lacertae objects: mkn 501
CODE: renault2001