//////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27738 SUBJECT: GRB200514B: ATLAS detections of ZTF20aazpphd DATE: 20/05/14 20:36:48 GMT FROM: Stephen Smartt at Queen's U/Belfast S. J. Smartt, K. W. Smith (QUB), S. Srivastav, T.-W. Chen (MPE), D. R. Young, M. Fulton, (QUB) L. Denneau, H. Flewelling, A. Heinze, J. Tonry, H. Weiland (IfA, Univ. Hawaii), A. Rest (STScI), B. Stalder (LSST), C. Stubbs (Harvard), O. McBrien, J. Gillanders, D. O'Neil, P. Clark (QUB) The transient ZTF20aazpphd (AT2020jww) was reported by Ahumada et al. (GCN 27737) at r = 19.6 +/- 0.05 within the localization region of the short GRB200514B (trigger 611140062) detected by the Gamma-Ray Burst Monitor (GBM) on the Fermi satellite at MJD = 58983.38029 (GCN 27736). ATLAS, the twin telescope system on Haleakala and Mauna Loa was observing this region of sky in normal sky operations (Tonry et al. 2018, PASP, 130f4505, Smith et al. 2020, arXiv:2003.09052). We detect ZTF20aazpphd before the ZTF epoch at the following magnitudes : ATLAS c-band : MJD dt m err 58983.42278 +1.02 19.47 0.13 58983.42461 +1.06 19.18 0.20 58983.43478 +1.31 19.46 0.13 58983.43890 +1.41 19.42 0.21 where dt is the time in hrs since Fermi trigger. ZTF reported the r-band : 58983.49 +2.63 19.6 0.05 The first ATLAS detection is 1.61hrs before the ZTF in the cyan-band (a composite g+r filter). The two magnitudes are consistent, given the errors and the different filter profiles. Therefore there is no evidence of any rapid decline within this short interval, as might be expected for a sGRB afterglow. We also have non-detections of ZTF20aazpphd 2 days before, hence it is more likely a young supernova. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27739 SUBJECT: GRB 200514B: GROWTH-India follow-up of ZTF20aazpphd (AT2020jww) DATE: 20/05/14 22:39:14 GMT FROM: Harsh Kumar at Indian Inst of Tech,Bombay H. Kumar, V. Bhalerao(IITB), G. C. Anupama, S. Barway(IIA), U. Stanzin(IAO) report on behalf of the GROWTH-India collaboration: We observed ZTF20aazpphd (AT2020jww) reported by (T. Ahumada et al., GCN 27737, S. J. Smartt et al., GCN 27738) with 0.7m GROWTH-India telescope. We obtained g band exposures starting at UT 20-05-14T17:22:52. The transient was reported in GCN 27737 as a followup of the GRB200514B event detected by Fermi GBM (GCN 27736). We obtained the following photometric results:- ------------------------------------------------------------------ MJD(Start)| T-T0(hrs) | Exposure(sec) | Filter | Mag | ------------------------------------------------------------------ 58983.724 | 8.25 | 600 | g | 19.20 +/- 0.04 | 58983.732 | 8.44 | 600 | g | 19.15 +/- 0.04| 58983.863 | 11.58 | 500 | g | 19.12 +/- 0.05 | ------------------------------------------------------------------ The transient is not fading like a GRB afterglow as per our observation in the g band. Hence, seems unrelated to the GRB200514B event. The GROWTH India Telescope (GIT) is a 70-cm telescope with a 0.7 degree field of view, set up by the Indian Institute of Astrophysics and the Indian Institute of Technology Bombay with support from the Indo-US Science and Technology Forum (IUSSTF) and the Science and Engineering Research Board (SERB) of the Department of Science and Technology (DST), Government of India (https://sites.google.com/view/growthindia/). It is located at the Indian Astronomical Observatory (Hanle), operated by the Indian Institute of Astrophysics (IIA). //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27740 SUBJECT: Optical transient ZTF20aazpphd is unrelated to GRB 200514B DATE: 20/05/14 22:45:08 GMT FROM: Christian Malacaria at NASA-MSFC/USRA C. Malacaria (NASA/MSFC-USRA) and E. Burns (GSFC) report on behalf of the Fermi-GBM Team: At 09:07:37 UT on 14 May 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200514B (GCN 27736, Fermi-GBM Team). Follow-up observations by the Zwicky Transient Facility identified ZTF20aazpphd as a potential optical counterpart to GRB 200514B (Ahumada et al., GCN 27737). ZTF20aazpphd was subsequently observed by ATLAS, who found no evidence for rapid decline (Smartt et al., GCN 27738), contrary to what expected for a short GRB afterglow. We also verified that, when GBM triggered on GRB 200514B, the source position for ZTF20aazpphd as observed by GBM was occulted by Earth and therefore unobservable. We therefore conclude that the optical transient ZTF20aazpphd is unrelated to GRB 200514B. //////////////////////////////////////////////////////////////////////// TITLE: GCN CIRCULAR NUMBER: 27741 SUBJECT: GRB200514B: YSE detection of ZTF20aazpphd DATE: 20/05/14 23:00:35 GMT FROM: David Jones at UC,Santa Cruz D. O. Jones (UC Santa Cruz), K. D. French (Carnegie, Illinois), A. Agnello, C. R. Angus, Z. Ansari, N. Arendse, C. Gall, C. Grillo, S. H. Bruun, C. Hede, J. Hjorth, L. Izzo, H. Korhonen, S. Raimundo, D. Kodi Ramanah, A. Sarangi, R. Wojtak (DARK, U Copenhagen), K. Auchettl (DARK, UC Santa Cruz, U Melbourne), K. C. Chambers, M. E. Huber, E. A. Magnier, T. J. L. de Boer, J. R. Fairlamb, C. C. Lin, R. J. Wainscoat, T. Lowe, M. Willman, J. Bulger, A. S. B. Schultz (IfA, Hawaii), A. Engel, A. Gagliano, G. Narayan, M. Soraisam (Illinois), Q. Wang (JHU), A. Rest (JHU, STScI), S. J. Smartt, K. W. Smith (Queen's University Belfast), K. D. Alexander, A. Baldeschi, P. Blanchard, D. Coppejans, L. DeMarchi, A. Hajela, W. Jacobson-Galan, R. Margutti, D. Matthews, C. Stauffer, M. Stroh, G. Terreran (Northwestern), M. Drout (U Toronto), D. A. Coulter, G. Dimitriadis, R. J. Foley, T. Hung, C. D. Kilpatrick, C. Rojas-Bravo, M. R. Siebert (UC Santa Cruz), E. Ramirez-Ruiz (UC Santa Cruz, DARK) The ZTF and ATLAS collaborations (Ahumada et al., GCN 27737; Smartt et al., GCN 27738) have both reported observations of ZTF20aazpphd (AT2020jww), a transient within the localization region of short GRB200514B (trigger 611140062). GRB200514B was detected at MJD = 58983.38029 by the Gamma-Ray Burst Monitor on the Fermi satellite (GCN 27736). The Young Supernova Experiment (YSE; ATel 13330) also observed this region of the sky with Pan-STARRS1 on Haleakala (Chambers et al., 2016). We detected ZTF20aazpphd in gi bands with an g-i color of -0.57 +/- 0.12 mag: MJD dt band mag mag_err 58983.52303 +3.43 g_P1 19.197 0.079 58983.52573 +3.49 i_P1 19.766 0.094 The dt column is the time since GRB200514B was discovered in hours. These measurements were taken 0.8 hours after the ZTF r-band observation, 1.75 hours after the ZTF g observation and 2.4 hours after ATLAS observations (Smartt et al., GCN 27738). They are consistent with magnitudes from ZTF (g = 19.249 +/- 0.047) and ATLAS. Our data do not show evidence for the rapid decline characteristic of a sGRB over the time baseline of ~2.4 hours.