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GCN Circular 36135

EP240413a: BOOTES-2/TELMA Optical Upper Limit
2024-04-16T13:10:33Z (a month ago)
Dingrong Xiong at Yunnan Observatories of CAS, China <>
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D. R. Xiong, J. M. Bai, J. R. Mao, Y. F. Fan, K. Ye, C. J. Wang, Y. X. Xin, B. L. Lun, J. J. Zhang, X. H. Zhao, L. Xu, K. X. Lu, X. Ding, D. Q. Wang, S. S. He(Yunnan Observatories/CAS), A. J. Castro-Tirado, E. Fernandez-Garcia, Y. D. Hu (IAA-CSIC) and C. J. Perez del Pulgar (UMA) on behalf of the BOOTES team report:

We observed the fast X-ray transient EP240413a (R.A. = 228.815 deg, DEC = -18.503 deg; Lian et al., GCN 36086, Li et al., GCN 36092) with BOOTES-2/TELMA robotic telescope, and did not found any optical counterpart within an uncertainty of 30 arcsec in radius.

The upper limits of magnitudes (without being corrected for Galactic extinction) are given as follows. 

FXT T0 | Tmid-T0 (day) | UT (start) | Upper Limit (error) | Exposure Time | Filter 


24-04-14T04:40:26| 0.86 | 04-15T01:21:09 | 17.623 (0.13) | 10*60s (co-added) | Clear  


The Burst Optical Observer and Transient Exploring System (BOOTES) is a world-wide automatic telescope network which aims to repaid follow-up of transient and astrophysical sources in the sky for which the first station was installed in 1998 (Castro-Tirado et al. 1999; Hu et al. 2021). The BOOTES-2/TELMA robotic telescope at IHSM La Mayora (UMA-CSIC) in Algarrobo Costa (Malaga, Spain). We acknowledge the support of these staffs from the BOOTES telescope networks.


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