English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We investigate the temporal and colour variability of 897 blazars, comprising455 BL Lacertae objects (BL Lacs) and 442 Flat Spectrum Radio Quasars (FSRQs),selected from the Roma-BZCAT catalogue, using the multi-band light curves fromthe Zwicky Transient Facility (ZTF DR6) survey. Assessing the colourvariability characteristics over ~2 year timescales, we found that 18.5 percent (84 out of 455) BL Lacs showed a stronger bluer when brighter (BWB) trend,whereas 9.0 per cent (41 out of 455) showed a redder when brighter (RWB) trend.The majority (70 per cent) of the BL Lacs showing RWB are host galaxydominated. For the FSRQ subclass, 10.2 per cent (45 out of 442) objects showeda strong BWB trend and 17.6 per cent (78 out of 442) showed a strong RWB trend.Hence we find that BL Lacs more commonly follow a BWB trend than do FSRQs. Thiscan be attributed to the more dominant jet emission in the case of BL Lacs andthe contribution of thermal emission from the accretion disc for FSRQs. Inanalysing the colour behaviour on shorter time windows, we find many blazarsevince shorter partial trends of BWB or RWB nature (or occasionally both). Someof such complex colour behaviours observed in the colour-magnitude diagrams ofthe blazars may result from transitions between the jet-dominated state to thedisc-dominated state and vice versa.

Optical Flux and Colour Variability of Blazars in the ZTF Survey