Request for photometric follow-up of a candidate LFBOT AT2026cex

[Joysankar Majumdar]

Dear observers,

I am Joysankar Majumdar, and I am a PhD student working with Lukasz's group at the Astronomical Observatory, University of Warsaw.

I am writing to request photometric follow-up observations of a newly reported fast blue optical transient (LFBOT) AT2026cex. This was identified very recently, and AT2026cex appears to have entered a rapid decline phase, making timely observations very crucial.

AT2026cex exhibits a featureless blue spectrum (ATel#17646). LFBOTs are rare and evolve on very short timescales, with rapid post-peak fading and strong color evolution. During the declining phase, good photometry can help to constrain decay rates, color evolution, and potential source activity.

We are particularly interested in blue bands (g/B), complemented by r and i when possible, for color evolution. Nightly monitoring over the coming days would be extremely valuable, though any prompt observations are greatly appreciated. AT2026cex is readily visible from most Northern Hemisphere, where it rises to a comfortable altitude for several hours each night.

Given the rarity of this kind of transient and the short-lived nature of its optical emission, coordinated photometric coverage during this declining phase would be a very good science.

With best regards,
Joysankar