Asteroids & J-Var

The Javalambre VARiability Survey (J-VAR) is a photometric survey that is being carried out with the 0.8m Javalambre Auxiliary Survey Telescope (JAST80), located at the Observatorio Astronómico de Javalambre (OAJ), near Teruel. J-VAR is the time-domain extension of the Javalambre-Photometric Local Universe Survey, J-PLUS [1], carried out in the same telescope. J-VAR uses a sub-set of seven filters from the J-PLUS set covering the range from 0.395 up to 0.861 microns, including the g,r,i filters from the SDSS set. The survey has been carried out in non-photometric conditions, using open time from 2019 to the end of 2022, continuing as a filler program since 2023, and the photometric calibration of the fields relies, by construction, on secondary calibrations based on already observed J-PLUS fields, which are regularly calibrated [2]. The main concept of J-VAR is to explore the time-domain capabilities offered by the JAST80. J-VAR includes three main scientific lines: characterization of variable stars, supernovae detection, and small bodies detection and characterization. We will only speak about the last leg in this presentation. The strategy of J-VAR is as follows: each field is observed three times, with dithering, in all seven filters, and is revisited a total of ten times whenever the weather conditions allow J-VAR to be executed. Ideally, it should not be more than a few days (of the order of a week), although this timespan could be of the order of months, depending on the weather. The fields of J-VAR have been selected as a compromise to maximize scientific output from the three main lines. Survey Status: The team is currently finishing up the secondary calibration software. So far, we have only made it manually for a few selected targets for sanity checks. A first run of the SSOS pipeline on fields observed between early 2018 and mid 2021 include about 82,000 detections of moving objects up to V=20. We are currently preparing Data Release 1 (DR1) of J-VAR and the first scientific papers with the analysis of the first 100 completed fields. Expectations: According to our estimates, we expect to detect around 30 objects per night with at least four filters. The number of nights of the complete survey strongly depend on the availability of nights at the telescope, where J-VAR co-habits with five other surveys, including J-PLUS, as a filler program. The data on small bodies could be used as a stand-along database, but its full potential will be achieved once joined with those of J-PLUS (see MOOJa catalog [3]). Acknowledgments: This project has been supported by the Spanish Ministry of Science and Innovation through the project PID2021-124918NB-C42. This work is based on observations figmade with the JAST80 telescope at the OAJ (Teruel), owned, managed, and operated by the Centro de Estudios de Física del Cosmos de Aragón (CEFCA). We acknowledge the OAJ Data Processing and Archiving Unit (UPAD) for reducing the OAJ data used in this work.

[1] Cenarro, J. et al. (2019) A&A, 622, A176

[2] Lopéz-SanJuan et al. (2019) A&A, 631, A119

[3] Morate et al. (2021) A&A, 655, A47