A balloon-borne imaging telescope for high-energy astrophysics

Villela, T.; Braga, J.; D'Amico, F.; Jayanthi, U. B.; Neri, J.A.C.F.

doi:10.1007/bf00982333

Cited by 10 publications

(1 citation statement)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The MASCO experiment 19,20 is a balloon-borne imaging gamma-ray telescope designed to operate in the 50 keV-1.8 MeV energy range with a ϳ14 arcmin angular resolution. The telescope has a circular 13.6°-diam fully coded field of view ͑FCFOV͒ surrounded by a partially coded field of view ͑PCFOV͒ up to 23.5°.…”

Section: Description Of the Instrumentmentioning

confidence: 99%

Development of the imaging system of the balloon-borne gamma-ray telescope Máscara Codificada (MASCO)

Braga

D'Amico

Villela

et al. 2002

Review of Scientific Instruments

View full text Add to dashboard Cite

We report laboratory imaging results of a balloon-borne gamma-ray imaging telescope, Máscara Codificada ͑Portuguese for ''coded mask,''͒ designed to obtain high angular resolution ͑ϳ14 arcmin͒ images of the sky in the 50 keV-1.8 MeV energy range. The instrument incorporates a coded mask with an aperture pattern based on a 19ϫ19-element modified uniformly redundant array ͑MURA͒. This pattern belongs to a subclass of MURAs that are almost completely antisymmetrical for 90°rotations with respect to the lower-right corner of the central element, which allows the implementation of an antimask by a single rotation of the whole mask by 90°. The symmetry properties of the MURAs are discussed. The algorithm for determining the position of the gamma-ray interactions on the instrument's main detector is described and the results of laboratory tests of the imaging system are presented. The mask-antimask subtraction, applied after a flat-fielding procedure, produced a 60% increase in the signal-to-noise ratio of a strong ͑ϳ100͒ point source ͑662 keV photons coming from a 137 Cs radioactive source͒ image by eliminating systematic distortions in the instrumental background measured over the detector plane.

show abstract

Section: Description Of the Instrumentmentioning

confidence: 99%