TITLE: GCN CIRCULAR NUMBER: 21010 SUBJECT: LIGO/Virgo G275404: DLT40 follow-up observation DATE: 17/04/14 17:53:57 GMT FROM: Sheng Yang at UC Davis Sheng Yang (INAF-OAPd, UC Davis), Stefano Valenti (UC Davis), David Sand (TTU), Leonardo Tartaglia (TTU, UC Davis), Enrico Cappellaro (INAF-OAPd), Dan Reichart, Josh Haislip (UNC), G. Hosseinzadeh, I. Arcavi, D. A. Howell, C. McCully (Las Cumbres Obs./UCSB) report on behalf of the Gravitational Wave Follow-Up by DLT40. We report the observation of 50 galaxies within the LVC error region for the GW trigger G275404 using the 'bayestar' GW localization map from 2017-2-26 to 2017-3-9. Starting from 2017-3-9 (until 2017-3-12) we observed 84 galaxies using the update LALInference localization map. We selected galaxies from the GWGC catalogue within 80.0% of the trigger error region, within a distance of 40.0 Mpc, brighter than -17.5 mag and at a Declination < 20 degree. Those selected galaxies have been observed using the Prompt 5 telescope and they are part of the ongoing DLT40 search. The first 50 galaxies represent the 3.9% of all galaxies in the Glade catalogue within 40.0 Mpc and within the LVC error region for the GW trigger. They also contain 12.7% of all B band luminosity of those galaxies. The 84 galaxies, observed after 2017-3-9, represent the 1.5% of all galaxies and contains 9.7% of all B band luminosity. The DLT40 search limit magnitude, for those galaxies is 19.2 (open filter scaled to r band). We found one SN Ia, SN2017cbv/DLT17u, in NGC5642 on 2017-3-8, which is only 16 Mpc away. Our follow-up observations of SN2017cbv/DLT17u with Las Cumbres Observatory telescopes show that SN2017cbv/DLT17u has recently reached its maximum luminosity (Bmag ~ 11.79) 17.7 days after discovery. Giving the typical rise time of SNe Ia (18.98 ± 0.54 days, Firth, R. E., et al. 2014, MNRAS 446, p.3895-3910), SN2017cbv was discovered very close to explosion and we can then exclude that SN2017cbv is related to the GW event that occurred ~ 2 weeks before the explosion epoch of SN2017cbv. Below follow the list of galaxies observed: Name RA(J2000) DEC(J2000) Dist(Mpc) BMAG KMAG OBS_WINDOW(JD) ESO176-006 224.29 -54.39 38.01 -21.5 -24.4 2457821.57-2457825.39 NGC4696 192.20 -41.31 35.48 -21.4 -25.6 2457821.57-2457825.39 ESO380-006 183.89 -35.62 38.93 -21.3 -24.7 2457821.57-2457825.39 NGC6384 263.10 7.0603 25.94 -21.2 -24.5 2457821.57-2457825.39 NGC3962 178.66 -13.97 35.32 -21.2 -25.0 2457821.57-2457825.39 NGC5078 199.95 -27.41 27.67 -21.2 -25.0 2457821.57-2457825.39 NGC4603 190.23 -40.97 33.11 -21.2 -24.2 2457821.57-2457825.39 NGC5643 218.16 -44.17 18.45 -21.1 -24.1 2457821.57-2457825.39 NGC5266 205.75 -48.16 38.02 -21.1 -25.4 2457821.57-2457825.39 IC3253 185.93 -34.62 34.67 -21.0 -23.5 2451870.67-2457825.39 NGC3706 172.43 -36.39 38.02 -21.0 -24.9 2457821.57-2457825.39 NGC6574 272.96 14.981 38.91 -20.9 -24.5 2457821.57-2457825.39 NGC3923 177.75 -28.80 22.91 -20.9 -25.3 2451870.67-2457825.39 NGC3338 160.53 13.747 24.43 -20.9 -23.8 2457821.57-2457825.39 NGC5156 202.18 -48.91 36.98 -20.9 -24.1 2457821.57-2457825.39 ESO320-026 177.45 -38.78 38.02 -20.9 -24.2 2457821.57-2457825.39 NGC4976 197.15 -49.50 17.3 -20.9 -24.3 2457821.57-2457825.39 ESO271-022 213.37 -45.41 38.14 -20.8 -23.1 2457821.57-2457825.39 NGC6555 271.95 17.604 33.42 -20.8 -22.7 2457821.57-2457825.39 IC2977 178.81 -37.69 39.01 -20.8 -23.8 2457821.57-2457825.39 NGC5061 199.52 -26.83 24.21 -20.8 -24.6 2457821.57-2457825.39 IC4351 209.47 -29.31 27.54 -20.8 -24.1 2457821.57-2457825.39 NGC3749 173.97 -37.99 38.02 -20.8 -24.1 2457821.57-2457825.39 NGC3672 171.26 -9.795 23.66 -20.7 -23.6 2457821.57-2457825.39 NGC3585 168.32 -26.75 20.05 -20.7 -24.8 2457821.57-2457825.39 NGC5266A 205.15 -48.34 38.02 -20.7 -22.2 2457821.57-2457825.39 ESO442-026 193.05 -29.84 34.94 -20.7 -24.2 2457821.57-2457825.39 NGC5101 200.44 -27.43 24.21 -20.6 -24.7 2457821.57-2457825.39 ESO269-057 197.51 -46.43 36.98 -20.6 -24.0 2457821.57-2457825.39 NGC4373A 186.40 -39.31 37.33 -20.6 -24.0 2457821.57-2457825.39 PGC086291 282.99 11.876 38.02 -20.6 -24.0 2451870.67-2457825.39 NGC4444 187.15 -43.26 36.98 -20.6 -23.4 2457821.57-2457825.39 PGC054411 228.64 -52.98 19.36 -20.6 -24.2 2457821.57-2457825.39 NGC5688 219.89 -45.01 30.9 -20.5 -24.1 2457821.57-2457825.39 IC4214 199.42 -32.10 28.84 -20.5 -24.0 2457821.57-2457825.39 NGC3742 173.88 -37.95 38.61 -20.5 -24.2 2457821.57-2457825.39 NGC4112 181.78 -40.20 34.67 -20.5 -23.4 2457821.57-2457825.39 ESO221-010 207.73 -49.05 38.02 -20.5 -23.6 2457821.57-2457825.39 NGC3904 177.30 -29.27 28.31 -20.5 -24.5 2451870.67-2457825.39 NGC4219 184.11 -43.32 20.99 -20.5 -23.5 2457821.57-2457825.39 NGC3783 174.75 -37.73 38.02 -20.5 -24.2 2457821.57-2457825.39 ESO320-031 178.52 -39.86 38.18 -20.4 -24.8 2457821.57-2457825.39 ESO385-030 217.33 -33.45 34.33 -20.4 -24.0 2457821.57-2457825.39 NGC5219 204.67 -45.85 36.98 -20.4 -22.8 2457821.57-2457825.39 NGC2992 146.42 -14.32 28.84 -20.3 -23.7 2457821.57-2457825.39 NGC4767 193.47 -39.71 32.81 -20.3 -24.3 2457821.57-2457825.39 ESO175-005 214.44 -52.83 37.36 -20.3 -20.2 2457821.57-2457825.39 IC3370 186.90 -39.33 26.79 -20.3 -24.2 2457821.57-2457825.39 ESO380-019 185.50 -35.79 38.02 -20.3 -24.2 2451870.67-2457825.39 PGC046029 198.58 -46.12 36.98 -20.3 -24.3 2457821.57-2457825.39 NGC5063 199.60 -35.35 33.39 -20.3 -23.2 2457821.57-2457825.39 NGC5365 209.46 -43.93 32.36 -20.3 -24.6 2457821.57-2457825.39 ESO321-025 185.42 -39.76 29.38 -20.3 -22.5 2457821.57-2457825.39 NGC4947 196.33 -35.33 27.8 -20.3 -23.1 2451870.67-2457825.39 NGC5085 200.07 -24.44 24.21 -20.3 -22.9 2457821.57-2457825.39 NGC4105 181.67 -29.76 26.55 -20.3 -24.5 2451870.67-2457825.39 NGC3169 153.56 3.4664 18.45 -20.3 -24.0 2457821.57-2457825.39 ESO221-014 208.02 -48.17 35.81 -20.2 -23.1 2457821.57-2457825.39 NGC5365A 209.16 -44.00 36.98 -20.2 -24.0 2457821.57-2457825.39 ESO221-025 211.89 -48.39 38.93 -20.2 -19.4 2457821.57-2457825.39 ESO320-030 178.29 -39.13 38.02 -20.2 -23.6 2457821.57-2457825.39 NGC3459 163.68 -17.04 31.61 -20.2 -22.4 2451870.67-2457825.39 NGC2967 145.51 0.3365 29.92 -20.2 -23.4 2457821.57-2457825.39 IC4197 197.01 -23.79 34.1 -20.2 -23.3 2457821.57-2457825.39 NGC4304 185.55 -33.48 34.67 -20.2 -23.6 2451870.67-2457825.39 ESO377-024 168.13 -36.42 38.21 -20.2 -22.9 2457821.57-2457825.39 NGC4835 194.53 -46.26 20.14 -20.2 -23.3 2457821.57-2457825.39 NGC5483 212.60 -43.32 24.21 -20.2 -23.4 2457821.57-2457825.39 IC4444 217.91 -43.41 25.35 -20.2 -23.4 2457821.57-2457825.39 ESO507-032 193.06 -26.30 20.82 -20.2 -22.3 2457821.57-2457825.39 NGC6570 272.78 14.093 33.42 -20.2 -22.7 2457821.57-2457825.39 NGC5188 202.86 -34.79 28.84 -20.2 -23.7 2457821.57-2457825.39 NGC4993 197.44 -23.38 33.81 -20.2 -23.4 2457821.57-2457825.39 NGC5494 213.1 -30.64 31.19 -20.1 -23.4 2457821.57-2457825.39 NGC3368 161.69 11.819 10.47 -20.1 -23.7 2457821.57-2457825.39 ESO221-020 209.59 -48.47 38.29 -20.1 -23.6 2457821.57-2457825.39 ESO321-016 183.86 -38.14 38.02 -20.1 -21.9 2457821.57-2457825.39 ESO380-050 189.58 -35.61 38.02 -20.1 -20.5 2451870.67-2457825.39 NGC3115 151.30 -7.718 10.33 -20.1 -24.1 2457821.57-2457825.39 IC0764 182.55 -29.73 21.18 -20.1 -21.9 2451870.67-2457825.39 ESO221-026 212.09 -47.97 20.31 -20.1 -23.9 2457821.57-2457825.39 NGC4462 187.33 -23.16 23.12 -20.1 -23.3 2457821.57-2457825.39 ESO386-039 224.10 -37.60 36.98 -20.1 -22.8 2457821.57-2457825.39 ESO221-012 207.88 -48.08 38.02 -20.1 -21.9 2457821.57-2457825.39 PGC033108 164.90 -15.52 35.63 -20.0 -21.2 2451870.67-2457821.57 ESO441-017 182.78 -31.12 24.24 -19.9 -21.0 2451870.67-2457821.57 NGC3321 159.71 -11.64 33.88 -19.8 -22.1 2451870.67-2457821.57 NGC3044 148.42 1.5796 21.68 -19.8 -22.6 2451870.67-2457821.57 NGC3885 176.69 -27.92 21.88 -19.7 -23.3 2451870.67-2457821.57 IC0630 159.64 -7.170 25.85 -19.7 -23.4 2451870.67-2457821.57 ESO324-044 204.52 -39.84 34.51 -19.7 -21.8 2451870.67-2457821.57 NGC3511 165.84 -23.08 12.25 -19.6 -22.3 2451870.67-2457821.57 IC2627 167.47 -23.72 24.21 -19.6 -22.9 2451870.67-2457821.57 NGC5121 201.19 -37.68 20.8 -19.5 -23.1 2451870.67-2457821.57 NGC3936 178.08 -26.90 18.62 -19.5 -22.2 2451870.67-2457821.57 NGC3055 148.82 4.27 25.35 -19.5 -22.5 2451870.67-2457821.57 NGC3375 161.75 -9.941 28.87 -19.5 -22.5 2451870.67-2457821.57 IC3015 182.25 -31.51 24.21 -19.5 -23.1 2451870.67-2457821.57 IC2995 181.44 -27.94 16.75 -19.4 -21.8 2451870.67-2457821.57 ESO381-029 194.11 -36.37 29.54 -19.3 -22.6 2451870.67-2457821.57 ESO569-014 162.85 -19.89 24.77 -19.3 -20.9 2451870.67-2457821.57 IC0760 181.47 -29.29 25.37 -19.2 -22.6 2451870.67-2457821.57 IC3010 181.98 -30.33 25.87 -19.2 -22.8 2451870.67-2457821.57 ESO440-011 177.19 -28.29 21.88 -19.2 -18.0 2451870.67-2457821.57 NGC3673 171.30 -26.73 17.38 -19.2 -22.6 2451870.67-2457821.57 NGC3361 161.12 -11.20 24.21 -19.1 -21.8 2451870.67-2457821.57 ESO440-038 180.42 -31.70 26.65 -19.1 -22.0 2451870.67-2457821.57 UGC05347 149.31 4.5269 29.92 -19.0 -20.2 2451870.67-2457821.57 IC3005 181.80 -30.02 24.32 -19.0 -21.9 2451870.67-2457821.57 ESO440-049 181.39 -31.42 24.24 -18.9 -20.1 2451870.67-2457821.57 ESO440-027 178.35 -28.55 18.53 -18.9 -21.7 2451870.67-2457821.57 NGC3617 169.46 -26.13 25.61 -18.9 -22.2 2451870.67-2457821.57 ESO504-028 178.72 -27.25 22.24 -18.8 -20.2 2451870.67-2457821.57 ESO440-004 176.42 -28.36 22.93 -18.8 -18.4 2451870.67-2457821.57 UGC05376 150.11 3.3744 29.92 -18.8 -22.5 2451870.67-2457821.57 ESO381-038 195.02 -34.43 28.37 -18.7 -20.3 2451870.67-2457821.57 PGC032091 161.29 -10.06 27.64 -18.6 -20.1 2451870.67-2457821.57 ESO441-014 182.55 -30.07 24.67 -18.6 -19.5 2451870.67-2457821.57 IC2996 181.45 -29.97 21.88 -18.4 -20.6 2451870.67-2457821.57 PGC031979 160.90 -9.856 24.21 -18.3 -19.8 2451870.67-2457821.57 ESO441-012 182.36 -32.51 24.21 -18.2 -21.7 2451870.67-2457821.57 ESO440-037 179.82 -28.90 22.99 -18.2 -20.9 2451870.67-2457821.57 ESO324-023 201.87 -38.17 14.26 -18.2 -19.1 2451870.67-2457821.57