BRITE-Constellation: Data processing and photometry

Abstract

The BRITE mission is a pioneering space project aimed at the long-term photometric monitoring of the brightest stars in the sky by means of a constellation of nano-satellites. Its main advantage is high photometric accuracy and time coverage inaccessible from the ground. The main aim of this paper is the presentation of procedures used to obtain high-precision photometry from a series of images acquired by the BRITE satellites in two modes of observing, stare and chopping. We developed two pipelines corresponding to the two modes of observing. The assessment of the performance of both pipelines is presented. It is based on two comparisons, which use data from six runs of the UniBRITE satellite: (i) comparison of photometry obtained by both pipelines on the same data, which were partly affected by charge transfer inefficiency (CTI), (ii) comparison of real scatter with theoretical expectations. It is shown that for CTI-affected observations, the chopping pipeline provides much better photometry than the other pipeline. For other observations, the results are comparable only for data obtained shortly after switching to chopping mode. Starting from about 2.5 years in orbit, the chopping mode of observing provides significantly better photometry for UniBRITE data than the stare mode. This paper shows that high-precision space photometry with low-cost nano-satellites is achievable. The proposed meth- ods, used to obtain photometry from images affected by high impulsive noise, can be applied to data from other space missions or even to data acquired from ground-based observations.

References in corpus (5)

• Calibrated griz magnitudes of Tycho stars: All-sky photometric calibration using bright stars
• The BRITE Constellation nanosatellite mission: Testing, commissioning and operations
• The Most Massive Heartbeat: An In-depth Analysis of ι Orionis
• Combining BRITE and ground-based photometry for the Beta Cephei star Nu Eridani: impact on photometric pulsation mode identification and detection of several g modes
• On the efficiency of techniques for the reduction of impulsive noise in astronomical images

Cited by in corpus (6)

• BRITE-Constellation high-precision time-dependent photometry of the early-O-type supergiant $\zeta$ Puppis unveils the photospheric drivers of its small- and large-scale wind structures
• Machine learning search for variable stars
• Revisiting the pulsational characteristics of the exoplanet host star $\beta$ Pictoris
• $\epsilon$ Lupi: measuring the heartbeat of a doubly-magnetic massive binary with BRITE-Constellation
• BRITE-Constellation reveals evidence for pulsations in the enigmatic binary $\eta$ Carinae
• Constraining the near-core rotation of the gamma Doradus star 43 Cygni using BRITE-Constellation data