GRB140226A

This page lists all entries on GRB140226A in GRBweb

Summary IPN GCN 15888 GCN 15889 GCN 15891 GCN 15893 GCN 16037

Summary table
Variable Value Source
T0 10:02:57 UTC GCN_circulars,Konus-Wind Det
ra 221.4917° IPN
decl 15.0000° IPN
pos_error 1.67e-03° IPN
redshift 1.9800 IPN
GBM_located False
mjd 56714.41871527778 GCN_circulars,Konus-Wind Det
IPN table
GRB_name GRB140226A
ra 221.4917°
decl 15.0000°
pos_error 1.67e-03°
redshift 1.9800
GCN 15888 table
GRB_name GRB140226A
GCN_number 15888
Detection_method IPN Triangulation
ra 206.3050°
decl -7.9250°
Circular_text TITLE: GCN CIRCULAR NUMBER: 15888 SUBJECT: IPN triangulation of GRB 140226A, a possible GRB counterpart to iPTF14yb DATE: 14/02/28 00:25:44 GMT FROM: Kevin Hurley at UCBerkeley/SSL K. Hurley, on behalf of the Interplanetary Network, S. Golenetskii, R. Aptekar, V. Pal'shin, D. Frederiks, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin, on behalf of the HEND-Odyssey GRB team, W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr, on behalf of the GRS-Odyssey GRB team, A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, S. Barthelmy, J. Cummings, N. Gehrels, H. Krimm, and D. Palmer, on behalf of the Swift-BAT team, and V. Connaughton, M. S. Briggs, C. Meegan, and V. Pelassa, on behalf of the Fermi GBM team, report: We have examined IPN data for the period 2014-02-26T09:05:00 to 2014-02-26T10:18:00, when the optical transient source iPTF14yb was discovered (Cenko et al. GCN 15883). During this time, Konus, Swift, INTEGRAL, RHESSI, Odyssey, and MESSENGER were operating and returning data, although in the presence of increased solar activity. Suzaku was off. We have identified one event, at 2014-02-26T10:02:57 (36177 s), observed by Odyssey, INTEGRAL (SPI-ACS) and Konus (in the waiting mode), whose duration is ~15 s, and whose localization is consistent with iPTF14yb. Specifically, the Odyssey-INTEGRAL triangulation annulus is centered at RA, Dec = 206.305 degrees (13 h 45 m 13.2 s), -7.925 degrees (-7 o 55 ' 29 "), with radius 27.577 +/- 0.607 degrees (3 sigma). iPTF14yb lies 0.157 degrees from the center line of the annulus. The probability that the transient lies within the annulus by chance is roughly 0.005. At the time of this event, the optical transient was below the horizon for Swift, and no emission consistent with a GRB was seen in the data. Fermi was in the SAA. The RHESSI and MESSENGER backgrounds were high and variable due to solar activity, making the identification of this burst uncertain in their data. If this is indeed the GRB counterpart to iPTF14yb, this would appear to be the first GRB to be discovered on the basis of its optical counterpart. This triangulation can be improved. Detailed spectral and temporal information on this burst will be presented in a forthcoming GCN Circular.
GCN 15889 table
GRB_name GRB140226A
GCN_number 15889
Detection_method Konus-Wind Det
t_trigger 10:02:57 UTC
Circular_text TITLE: GCN CIRCULAR NUMBER: 15889 SUBJECT: Konus-Wind observation of GRB 140226A DATE: 14/02/28 08:16:29 GMT FROM: Dmitry Frederiks at Ioffe Institute S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind team, report: The long-duration GRB 140226A (IPN trangulation: Hurley et al., GCN 15888), which is a possible counterpart to the optical transient source iPTF14yb (Cenko et al. GCN 15883), was detected by Konus-Wind in the waiting mode against the high solar particle background. The light curve shows a single pulse, which peaked at T0=36177 s UT (10:02:57) and had a duration of ~15 s. As observed by Konus-Wind, the burst had a fluence of (5.6 1.1)x10^-6 erg/cm2 and a 2.944-s peak energy flux, measured from T0 of (8.6 1.7)x10^-7 erg/cm2 (both in the 20 - 10000 keV energy range). Modeling the KW 3-channel time-integrated spectrum (from T0-6.263 s to T0+5.513 s) by a power law with exponential cutoff model: dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep) yields alpha = -1.1 0.1, and Ep = 414 79 keV. All the quoted errors are estimated at 1 sigma confidence level. All the presented results are preliminary. The K-W light curve of this burst is available at http://www.ioffe.rssi.ru/LEA/GRBs/GRB140226A/
GCN 15891 table
GRB_name GRB140226A
GCN_number 15891
Detection_method Swift-XRT Other
Circular_text TITLE: GCN CIRCULAR NUMBER: 15891 SUBJECT: GRB 140226A / iPTF14yb: Swift-XRT confirms a fading X-ray source DATE: 14/02/28 15:11:10 GMT FROM: Andy Beardmore at U Leicester A.P. Beardmore (U. Leicester) reports on behalf of the Swift-XRT team: The Swift-XRT has continued to observe the source GRB 140226A / iPTF14yb (Cenko et al., GCN Circ. 15883; Cucchiara et al., GCN Circ. 15886; Varela et al., GCN Circ. 15887; Hurley et al., GCN Circ. 15888) and has now accumulated 9.1ks of data in Photon Counting (PC) mode. The X-ray light curve shows that the source announced by Beardmore et al. (GCN Circ. 15884) has faded, with a powerlaw decay index of 1.47 +0.29 -0.25 (with respect to the Konus-Wind T0; Golenetskii et al., GCN Circ. 15889). Taken together with the fading optical source and IPN localisation, the decaying X-ray source confirms the GRB origin of the object. The results of the XRT-team automatic analysis are available at http://www.swift.ac.uk/xrt_products/00033157.
GCN 15893 table
GRB_name GRB140226A
GCN_number 15893
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 15893 SUBJECT: GRB 140226A/iPTF14yb: Mondy optical observations DATE: 14/02/28 16:22:51 GMT FROM: Alexei Pozanenko at IKI, Moscow A.Volnova (IKI), A. Pozanenko (IKI), I. Korobtsev (ISTP), E. Klunko (ISTP), M. Eselevich (ISTP), report on behalf of larger GRB follow-up collaboration: We observed the field of transient iPTF14yb (Cenko et al., GCN 15883, Beardmore et al., GCN 15884, 15891) of possible GRB 140226A (Hurley et al., GCN 15888) with AZT-33IK telescope of Mondy observatory on Feb. 27 between (UT) 18:59:34 - 19:59:36. On a stacked R-filter image of 30 x 120 s we marginally detected iPTF14yb source with S/N ~2, and photometry of the source R = 23.0 at Feb. 27.81221 (mid). The photometry is based on SDSS J144600.66+145826.2 star assuming R(Lupton transformation)= 17.624 +/- 0.018
GCN 16037 table
GRB_name GRB140226A
GCN_number 16037
Detection_method Optical
Circular_text TITLE: GCN CIRCULAR NUMBER: 16037 SUBJECT: GRB 140226A/iPTF14yb: Mondy optical observations DATE: 14/03/25 15:11:32 GMT FROM: Alexei Pozanenko at IKI, Moscow A.Volnova (IKI), A. Pozanenko (IKI), I. Korobtsev (ISTP), E. Klunko (ISTP), M. Eselevich (ISTP), report on behalf of larger GRB follow-up collaboration: We observed the field of transient iPTF14yb (Cenko et al., GCN 15883, Beardmore et al., GCN 15884, 15891) a possible counterpart of GRB 140226A (Hurley et al., GCN 15888) with AZT-33IK telescope of Mondy observatory on Feb. 28 between (UT) 19:22:46 - 21:52:52 R-filter. On a stacked image of 75 x 120 s we clearly detected iPTF14yb source with a magnitude of R = 22.86 ± 0.17 at Feb. 28.85959 (mid) or 2.44087 days after GRB 140226A trigger (Hurley et al., GCN 15888). The photometry is based on SDSS J144600.66+145826.2 star assuming R(Lupton transformation)= 17.624 +/- 0.018.