The Journal of Astronomical Data 2018, Volume 24 ABSTRACTS
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[JAD 24, 1] Photometric data by the Delta Scuti Network I. 4 CVn
            M. Breger & P. Lenz
            
Nearly 1000 nights of high-precision photometry of the delta Scuti variable 4 CVn were obtained from 1966 to 2012. These data led to the discovery of 64+ frequencies of pulsation together with systematic changes in amplitudes and small period changes on a timescale of decades. This paper presents the previously unpublished data.
  
[2] BOOK REVIEW: In Memoriam Hilmar Duerbeck
    A. Verdun
    
[3] Optically Variable Quasars in the AllWISE and Pan-STARRS1 Data
    M. Usatov
    
    Multi-wavelength variability, arising due to the supermassive black hole accretion instabilities, is one of the intrinsic characteristics of active galactic nuclei (AGN). Combined with mid-infrared photometry, variability in optical continuum allows us to identify AGNs in the survey data. This work presents a sample of 229236 optically variable quasar candidates, identified in the final all-sky Wide-field Infrared Survey Explorer catalog and the Panoramic Survey Telescope and Rapid Response System Data Release 1 via a combination of 4 mid-infrared (3.4, 4.6, 12 and 22 micrometer; W1, W2, W3 and W4) and 5 optical (grizyP1) bands at 481, 617, 752, 866, and 962 nm. The selection criteria is based on the variability significance threshold set at 2-sigma and 3-sigma levels, and mid-infrared color cuts and spatial filters that prevent contamination from galactic sources. 127350 quasar candidates are found to be variable at the 3-sigma level. The cross-matching of this sample with the recent AGN catalogs resulted in 54218 point sources likely representing previously uncatalogued quasars, out of which 27845 exhibit variability at the 3-sigma level. The selection criteria used is tested against the ground truth sample from the AGN and Galaxy Evolution Survey in the 3.4 deg^2 crop of the Bootes field, indicating 82% reliability for quasars selected at the 2-sigma variability level, and 90% reliability for quasars selected at the 3-sigma level. Populations of candidates appearing as distinct concentrations in the mid-IR color space are identified, representing traditional quasars and, possibly, AGNs in starburst or ultraluminous infrared galaxies. The nature of remaining candidates may be explained as AGNs in late-type galaxies, however, additional research is required to gain certainty. 
    
    
[4] CCD photometry of CY Aquarii V. The 2016-2017-2018 seasons.
    C. Wiedemair, C. Sterken, T. Eenmäe, T. Tuvikene, D. Moser, L. Niederbrunner, V.  Oberhauser, M. Komar, P. Franzinelli and J. Enz
    
    Based on more than 37 partial nights of CCD monitoring, we derive 64 new times of maximum light of the SX Phoenicis star CY Aquarii. These times support a linear ephemeris for the time interval 2013-2018.