Variability and transient search in the SUDARE-VOICE field: A new method to extract the light curves

Dezi Liu, Wenqiang Deng, Zuhui Fan, Liping Fu, Giovanni Covone, Mattia Vaccari, Mario Radovich, Massimo Capaccioli, Demetra De Cicco, Aniello Grado, Lucia Marchetti, Nicola Napolitano, Maurizio Paolillo, Giuliano Pignata, Fabio Ragosta

Research output: Contribution to journalReview articlepeer-review

1 Citation (Scopus)


The VLT Survey Telescope (VST) Optical Imaging of the CDFS and ES1 Fields Survey, in synergy with the SUDARE survey, is a deep optical ugri imaging of the CDFS and ES1 fields using the VST. The observations for the CDFS field comprise about 4.38 deg2 down to r ~ 26 mag. The total on-sky time spans over 4 yr in this field, distributed over four adjacent subfields. In this paper, we use the multiepoch r-band imaging data to measure the variability of the detected objects and search for transients.We perform careful astrometric and photometric calibrations and point spread function modelling. A new method, referring to as differential running-average photometry, is proposed to measure the light curves of the detected objects. With the method, the difference of PSFs between different epochs can be reduced, and the background fluctuations are also suppressed. Detailed uncertainty analysis and detrending corrections on the light curves are performed. We visually inspect the light curves to select variable objects, and present some objects with interesting light curves. Further investigation of these objects in combination with multiband data will be presented in our forthcoming paper.

Original languageEnglish
Pages (from-to)3825-3837
Number of pages13
JournalMonthly Notices of the Royal Astronomical Society
Issue number3
Publication statusPublished - 1 Apr 2020


  • Catalogues
  • Methods: data analysis
  • Methods: observational
  • Surveys
  • Techniques: image processing
  • Techniques: photometric

ASJC Scopus subject areas

  • Astronomy and Astrophysics
  • Space and Planetary Science


Dive into the research topics of 'Variability and transient search in the SUDARE-VOICE field: A new method to extract the light curves'. Together they form a unique fingerprint.

Cite this