Observations of the first electromagnetic counterpart to a gravitational wave source by the TOROS collaboration

M. C. Díaz; L. M. Macri; D. Garcia Lambas; C. Mendes de Oliveira; J. L. Nilo Castellón; T. Ribeiro; B. Sánchez; W. Schoenell; L. R. Abramo; S. Akras; J. S. Alcaniz; R. Artola; M. Beroiz; S. Bonoli; J. Cabral; R. Camuccio; M. Castillo; V. Chavushyan; P. Coelho; C. Colazo; M. V. Costa-Duarte; H. Cuevas Larenas; D. L. DePoy; M. Domínguez Romero; D. Dultzin; D. Fernández; J. García; C. Girardini; D. R. Gonçalves; T. S. Gonçalves; S. Gurovich; Y. Jiménez-Teja; A. Kanaan; M. Lares; R. Lopes de Oliveira; O. López-Cruz; J. L. Marshall; R. Melia; A. Molino; N. Padilla; T. Peñuela; V. M. Placco; C. Quiñones; A. Ramírez Rivera; V. Renzi; L. Riguccini; E. Ríos-López; H. Rodriguez; L. Sampedro; M. Schneiter; L. Sodré; M. Starck; S. Torres-Flores; M. Tornatore; A. Zadrożny

doi:10.3847/2041-8213/aa9060

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arXiv · 1710.05844

Observations of the first electromagnetic counterpart to a gravitational wave source by the TOROS collaboration

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Abstract

We present the results of prompt optical follow-up of the electromagnetic counterpart of the gravitational-wave event GW170817 by the Transient Optical Robotic Observatory of the South Collaboration (TOROS). We detected highly significant dimming in the light curves of the counterpart (Delta g=0.17+-0.03 mag, Delta r=0.14+-0.02 mag, Delta i=0.10 +- 0.03 mag) over the course of only 80 minutes of observations obtained ~35 hr after the trigger with the T80-South telescope. A second epoch of observations, obtained ~59 hr after the event with the EABA 1.5m telescope, confirms the fast fading nature of the transient. The observed colors of the counterpart suggest that this event was a "blue kilonova" relatively free of lanthanides.

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M. C. Díaz, L. M. Macri, D. Garcia Lambas, C. Mendes de Oliveira, J. L. Nilo Castellón, T. Ribeiro, B. Sánchez, W. Schoenell, L. R. Abramo, S. Akras, J. S. Alcaniz, R. Artola, M. Beroiz, S. Bonoli, J. Cabral, R. Camuccio, M. Castillo, V. Chavushyan, P. Coelho, C. Colazo, M. V. Costa-Duarte, H. Cuevas Larenas, D. L. DePoy, M. Domínguez Romero, D. Dultzin, D. Fernández, J. García, C. Girardini, D. R. Gonçalves, T. S. Gonçalves, S. Gurovich, Y. Jiménez-Teja, A. Kanaan, M. Lares, R. Lopes de Oliveira, O. López-Cruz, J. L. Marshall, R. Melia, A. Molino, N. Padilla, T. Peñuela, V. M. Placco, C. Quiñones, A. Ramírez Rivera, V. Renzi, L. Riguccini, E. Ríos-López, H. Rodriguez, L. Sampedro, M. Schneiter, L. Sodré, M. Starck, S. Torres-Flores, M. Tornatore, A. Zadrożny. 2017-10-16. Observations of the first electromagnetic counterpart to a gravitational wave source by the TOROS collaboration. https://doi.org/10.3847/2041-8213%2Faa9060

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