Lead: Anna Ho (Cornell)

Desciption:In anticipation of ULTRASAT (launch expected in 2026), we propose to obtain near-continuous imaging of the northern ULTRASAT high-cadence field, and to autonomously trigger Swift on young and fast-brightening transients. Our goals are to (1) explore the minute-timescale optical sky by identifying transient and variable sources in the region, and (2) do a technical demonstration that Swift can autonomously observe a young optically-discovered transient.

Lead: Christoffer Fremling (Caltech)

Desciption: We aim for an experiment that is basically the Bright Transient Survey (BTS), but using 100% of the telescope time for three full nights instead of the usual 50%. We want to coordinate this with spectroscopic resources to be able to classify virtually all new transients (down to 19.5 mag) discovered during this dedicated effort. The aim is to quantify what we are missing at the fainter end where BTS is not complete, which will aid photometric classifiers that are needed both in the Vera Rubin era, but also to harvest the many tens of thousands of extragalactic transients in the ZTF archive for which we did not get spectroscopic classifications.

Lead: Yujing Qin (Caltech)

Desciption: The experiment aims to conduct a deep, snapshot-style survey of nearby galaxy overdensities including the Virgo, Coma, Hercules, and the Shapley supercluster to characterize the population properties of optical transients – their brightness, rising or fading rates, and host galaxy properties. The fewer number of pointings enables a longer exposure time, allowing for deeper sensitivity limits than the public survey. A catalog of transient candidates will be made available to the community.

Lead: Tomas Ahumada (Caltech)

The goal of this experiment is to exploit the usage of a DECam in tandem with ZTF and discover fast evolving transients in the overlapping area of these telescopes. With DECam, we will cover the same region on March 1st with one 30 sec g-band exposure and push candidates to Fritz. We plan to scan in real time and send interesting transients to other facilities for follow up.

Lead: Zach Vanderbosch (Caltech)

The ZTF Galactic science working group is undertaking a 3-night experiment to perform nearly all-night deep drilling of three individual fields, one per night. The goal of these observations will be to both detect and resolve stellar variability on all timescales covered by the baseline of a full night (~11 hr in January), and to assess the completeness of SCoPE periodicty detections in regions of different stellar densities by comparing SCoPE periods with periods detected within the experimental observations. The goals prompting the observations of the secondary fields are to to assess the feasibility and scientific return of near-simultaneous photometric and spectroscopic survey observations and to detect new variable sources within the COSMOS field, which is also planned for deep-drilling observations with Rubin-LSST.

Lead: Tomas Ahumada (Caltech)

The first pilot extragalactic ZTF experiment was carried out in Dec 2023. Distinct from regular ZTF operations, this experiment emphasizes densely sampled, intranight observations with deeper exposure, aiming at optimizing the detection efficiency of fast-evolving or newly emerging optical transients. Details and initial results were posted in this Astro Note.