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GCN Circular 36822

EP240703a: BOOTES-3 optical upper limit
2024-07-04T19:24:51Z (14 days ago)
Alberto Castro-Tirado at Astro. de Andalucia <>
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E. Fernandez-Garcia, I. Perez-Garcia, S.-Y. Wu, A. J. Castro-Tirado, M. D. Caballero-Garcia, I, Olivares, R. Sanchez-Ramirez and S. Guziy (IAA-CSIC), Y.-D. Hu (INAF-OAB), A. Castellon, S. Castillo, A. Reina and C. Perez del Pulgar (Univ. de Malaga), Ph. Yock (Univ. of Auckland), and R. Querel (NIWA), on behalf of a larger collaboration, report:

Following the detection of EP240703a by EP-WXT (Wang et al., GCNC 36807) and Konus-Wind (Frederiks et al., GCNC 36809), we triggered the 60cm BOOTES-3/YA robotic telescope at NIWA Lauder in Otago (New Zealand) to observe the fast X-ray transient location on Jul. 3 at 14:28 UT (13.9 hrs after the detection). No new optical source is detected on the co-added images (60 x 30 s, clear-filter) within the 3 arcmin radius EP error box (Wang et al. GCNC 36807) down to 20.5 mag,  which is consistent with the reports from Kinder (Aryan et al. GCNC 36819), TRT (An et al. GCNC 36820) and LT (Bochenek and Perley GCNC 36821) later on.

We thank the staff at NIWA at Lauder for its excellent support and especially to Bill Allen (1940-2023) for his invaluable  contribution in the early times at the Blenheim site where our former BOOTES-3 station was initially deployed on his vineyard (until it was moved to Lauder in 2014). Bill Allen, a vintner (besides an engineer & astronomer!) remains in our hearts and we remember him every night we are looking to the heavens thru our Yock-Allen (YA) robotic telescope at the new BOOTES-3 station.

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