GRB 260114A
GCN Circular 43509
Subject
GRB 260114A: SVOM/VT optical upper limits
Date
2026-01-25T04:16:37Z (3 months ago)
From
Yinuo Ma <mayn@bao.ac.cn>
Via
Web form
Y. N. Ma (NAOC), R. Z. Li (YNAO), L. P. Xin, H. L. Li, Z. H. Yao, Y. L. Qiu, C. Wu, X. H. Han, Y. Xu, J. Wang, P. P. Zhang, W. J. Xie, Y. J. Xiao, H. B. Cai, L. Lan, J. S. Deng, J. Y. Wei, D. H. Zhao (NAOC), J. Palmerio (CEA), B. T. Wang (YNAO), Y. H. Cheng (YNU) report on behalf of the SVOM/VT team.
SVOM/VT performed a Target of Opportunity observation of GRB 260114A detected by Swift/BAT, Fermi/GBM, SVOM/GRM, GECAM-B, Konus-Wind and Insight-HXMT/HE (Fermi GBM Team, GCN 43395; Eyles-Ferris et al., GCN 43396; Bissaldi, GCN 43400; Ren et al., GCN 43402; Wang et al., GCN 43404; Beardmore et al., GCN 43412; Ridnaia et al., GCN 43413; Ren et al., GCN 43503). SVOM/VT began observing the field at 2026-01-14 14:47:02 UTC, 3.11 hours after T0, in the VT_B (400nm-650nm) and VT_R (650nm-1000nm) channels simultaneously.
We performed the second observation as a template on January 19th. After performing image subtraction of our stacked images against the second observation, no uncataloged candidate was detected within the error box provided by Swift/XRT position (Beardmore et al., GCN 43412) or the optical counterpart previously reported by GMG (Li et al., GCN Circ. 43398) and the Mondy observatory (Volnova et al., GCN Circ. 43401). The three sigma limits are:
mid-time | exposure time | band | upper limit (AB)
----------|-----------------|-------|-----------------
4.241 h | 69*70 sec | VT_B | > 23.8 mag
4.251 h | 67*70 sec | VT_R | > 23.5 mag
Our results are consistent with MASTER (Lipunov et al., GCN Circ. 43403), NOT (Corcoran et al., GCN Circ. 43406), TNG (Brivio et al., GCN Circ. 43407), COLIBRÍ (Angulo et al., GCN 43408), MITSuME (Takahashi et al., GCN 43409), VLT (Yang et al., GCN 43414; Schneider et al ., GCN 43423) and Swift/UVOT (Siegel & Eyles-Ferris, GCN 43473).
The Space Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA, China), National Center for Space Studies (CNES, France) and the Chinese Academy of Sciences (CAS, China), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. VT was jointly developed by Xi'an Institute of Optics and Precision Mechanics (XIOPM), CAS and National astronomical observatories (NAOC), CAS.
GCN Circular 43503
Subject
GRB 260114A: Insight-HXMT/HE detection
Date
2026-01-23T11:58:54Z (4 months ago)
From
renyz16607@163.com
Via
Web form
Yang-Zhao Ren, Chen-Wei Wang, Cheng-Kui Li, Shao-Lin Xiong, and Chao Zheng (IHEP) report on behalf of the Insight-HXMT team:
At 2026-01-14T11:40:26.300 (T0), Insight-HXMT/HE detected a short burst, GRB 260114A, which is also detected by Fermi/GBM (Fermi GBM team, GCN #43395), Swift/BAT (Eyles-Ferris et al., GCN #43396), GECAM-B (Ren et al., GCN #43402), SVOM/GRM (Wang et al., GCN #43404), and Konus-Wind (Ridnaia et al., GCN #43413).
The Insight-HXMT/HE light curve mainly consists of multi-pulses with T90 of 0.28 +0.02/-0.02 s. The 1s peak rate, measured from T0-0.09 s, is 3104 cnts/sec. Insight-HXMT/HE detected a total of 3038 counts from this burst.
The Insight-HXMT /HE light curve can be found here:
https://www.bursthub.cn//admin/static/hxmtgrb260114A.png
All measurements above are made with the CsI detectors of Insight-HXMT/HE operating in the regular mode with the energy range of about 60-900 keV (deposited energy). Only gamma-rays with energy greater than about 200 keV can penetrate the spacecraft and leave signals in the CsI detectors installed inside of the telescope.
Insight-HXMT is the first Chinese space X-ray telescope, which was funded jointly by the China National Space Administration (CNSA) and the Chinese Academy of Sciences (CAS). More information about it could be found at: http://www.hxmt.org
GCN Circular 43473
Subject
GRB 260114A: Swift/UVOT Upper Limits
Date
2026-01-20T17:04:02Z (4 months ago)
From
Mike Siegel at PSU/Swift MOC <mhs18@psu.edu>
Via
Web form
M.H. Siegel (PSU) and R. A. J. Eyles-Ferris (U Leicester) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 260114A 164 s after the BAT trigger (Eyles-Ferris et al., GCN Circ. 43396). No optical afterglow consistent with the XRT position (Beardmore et al., GCN Circ 43412) or the faint red counterpart (Li et al., GCN Circ. 43398; Volnova et al, GCN Circ. 43401) is detected in the initial UVOT exposures. Preliminary 3-sigma upper limits using the UVOT photometric system(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the first
finding chart (FC) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white 164 848 102 >20.50
v 705 1100 52 >18.44
b 631 824 38 >19.22
u 507 799 136 >19.56
uvw1 755 774 19 >17.70
uvm2 730 750 19 >17.28
uvw2 681 1080 58 >18.59
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.069 in the direction of the burst
(Schlegel et al. 1998)
GCN Circular 43429
Subject
GRB 260114A: VLT/MUSE spectroscopic observations
Date
2026-01-16T21:38:14Z (4 months ago)
From
Andrea Saccardi at CEA/Irfu <andrea.saccardi@cea.fr>
Via
Web form
A. Saccardi (CEA/Irfu), D. B. Malesani (DAWN/NBI and Radboud), B. Schneider (LAM), G. Corcoran (UCD), H. Fausey (Baylor), L. Izzo (INAF/OACn & DARK/NBI), A. J. Levan (Radboud and Warwick), A. Martin-Carrillo (UCD), G. Tagliaferri (INAF/OAB), N. R. Tanvir (Leicester) report on behalf of the Stargate collaboration:
We observed the field of the short GRB 260114A (Eyles-Ferris et al., GCN 43396; Bissaldi, GCN 43400; Ren et al., GCN 43402; Wang et al., GCN 43404; Ridnaia et al., GCN 43413) using the ESO/VLT UT4 (Yepun) equipped with the MUSE integral-field spectrograph, covering 1'x1' centered around the XRT position. The observation mid time was 2026 Jan 15.155 UT (16.05 hr after the Swift/BAT trigger).
In proximity of the X-ray localization (Beardmore et al., GCN 43412), several objects are visible in archival images of the field, for some of which we report redshifts. These measurements are based on identification of emission lines due to, among others, [O III], Hbeta, and the [O II] doublet. The redshift of the first object in the list has been already reported by Yang et al. (GCN 43410).
Three of the objects have redshift close to z = 0.52, reinforcing that this is the likely GRB redshift.
We note the presence of a star in chance alignment with the galaxy at z = 0.524. Its spectrum easily identifies it as an early M star, and its PSF is unresolved down to ~0.5" seeing in our HAWK-I image (Schneider et al., GCN 43423).
| RA (J2000) | Dec (J2000) | Redshift | Comments |
| ----------- | ----------- | -------- | --------- |
| 04:58:23.43 | -08:00:50.5 | 0.524 | GCN 43410 |
| 04:58:23.57 | -08:00:52.2 | 0.514 | |
| 04:58:23.60 | -08:01:00.4 | 0.523 | |
| 04:58:22.72 | -08:00:47.7 | 0.288 | |
| 04:58:23.41 | -08:00:49.7 | 0 | M star |
A finding chart showing the positions of the above objects is posted at the following link (the XRT position is taken from https://www.swift.ac.uk/xrt_positions/):
https://sid.erda.dk/share_redirect/Ba6h5nsfin
We thank Phil Evans (Leicester) for insightful clarifications about the XRT localization. We also acknowledge excellent support from the observing staff at Paranal, in particular Thomas Rivinius, Julien Drevon, Camila de Sa Freitas, Rodrigo Romero.
GCN Circular 43423
Subject
GRB 260114A: VLT/HAWK-I further near-infrared upper limits
Date
2026-01-16T11:26:08Z (4 months ago)
Edited On
2026-01-16T16:14:08Z (4 months ago)
From
Benjamin Schneider at MIT <bschn@mit.edu>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Daniele Bjørn Malesani at Cosmic Dawn Center, Niels Bohr Institute <daniele.malesani@nbi.ku.dk>
Via
Web form
B. Schneider (LAM), D. B. Malesani (DAWN/NBI and Radboud), G. Corcoran (UCD), M. De Pasquale (Univ. Messina), H. Fausey (Baylor), B. P. Gompertz (Birmingham), A. J. Levan (Radboud and Warwick), R. Z. Li (Yunnan), A. Martin-Carrillo (UCD), G. Pugliese (API), A. Rossi (INAF-OAS), N. R. Tanvir (Leicester), A. L. Thakur (INAF-IAPS), S. D. Vergani (LUX-Paris Obs.) report on behalf of the Stargate collaboration:
We observed the field of the short GRB 260114A (Eyles-Ferris et al., GCN 43396; Bissaldi, GCN 43400; Ren et al., GCN 43402; Wang et al., GCN 43404; Ridnaia et al., GCN 43413) using the ESO/VLT UT4 equipped with the HAWK-I instrument. Observations were carried out over two nights, with mean epochs Jan 15.06 and 16.05UT (13.8 and 37.6 hr after the trigger, respectively), both in the H band, with an exposure time of 30 min each.
No new sources are detected consistent with the Swift/XRT position, except for two (possibly three) objects (Li et al., GCN 43398) visible in the Legacy survey, one of which is a galaxy at z = 0.524 (Yang et al., GCN 43410).
Image subtraction between the two epochs was carried out with HOTPANTS (Becker et al. 2015). No source is detected in the difference image down to a limiting magnitude H > 24.2 (AB, 3-sigma). Our non-detection is consistent with the limits provided by Brivio et al. (GCN 43407) and Yang et al. (GCN 43414).
We acknowledge excellent support from the observing staff at Paranal, in particular Thomas Rivinius, Julien Drevon, Camila de Sa Freitas, Rodrigo Romero.
GCN Circular 43416
Subject
GRB260114A: STEP/T80S optical limits
Date
2026-01-15T16:20:05Z (4 months ago)
From
André Santos at Centro Brasileiro de Pesquisas Físicas (CBPF) <andsouzasanttos@gmail.com>
Via
Web form
A. Santos (CBPF), C. R. Bom (CBPF), C. D. Kilpatrick (Northwestern), L. Santana-Silva (CBPF), P. Darc (CBPF/Northwestern), Gabriel Teixeira (CBPF/UCA), C. Mendes de Oliveira (IAG-USP) report on behalf of the STEP collaboration:
We conducted optical follow up with the T80S 0.8-m robotic telescope with the S-PLUS Transient Extension Program (STEP; Santos et al., 2024, MNRAS, 529, 59) of the short gamma-ray burst GRB260114A discovered by the Fermi-GBM, Swift-BAT and XRT instruments (GCN 43395,43396). The T80S observations started on Jan 15 03:18:38 UT (~16 hours after the trigger). We obtained images totaling 1200s (6x200s) in i-band with the T80S camera centered at the position reported in the Swift-BAT and XRT report at R.A.=04:58:23.59 and Decl.=-08:00:51.6 (J2000).
After subtracting a Pan-STARRS DR2 template image from the T80S coadded frame using photpipe (Rest et al., 2005, ApJ, 634, 1103), we do not detect any transient source in our difference image within the XRT error circle and derive a 3-sigma limiting magnitude of i > 22.4 mag.
GCN Circular 43414
Subject
GRB 260114A: VLT/HAWK-I near-infrared upper limits
Date
2026-01-15T14:29:46Z (4 months ago)
From
Yu-Han Yang at University of Rome Tor Vergata <yyang@roma2.infn.it>
Via
Web form
Yu-Han Yang, Muskan Yadav, Massine El Kabir, Niccolò Passaleva, Eleonora Troja, and Hira Waseem (U Rome) report:
We observed the field of GRB 260114A, detected by Swift (Eyles-Ferris et al., GCN 43396), Fermi (Fermi GBM Team, GCN 43395; E. Bissaldi et al. GCN 43400), GECAM-B (Ren et al., GCN 43402) and SVOM/GBM (SVOM/GRM team, GCN 43404) and Konus-Wind (Ridnaia et al., GCN 43413) with the HAWKI imager on the ESO VLT UT4 (Yepun). Observations began 14.2 hours after the trigger and were carried out in the J and Ks filters at an average airmass of 1.0.
Within the XRT source position (Beardmore et al., GCN 43412) several catalogued objects are visible in our images, however no obvious counterpart is detected down to a 3-sigma limit Ks>24 AB mag, calibrated using nearby stars in the 2MASS Catalog (Skrutskie et al. 2006).
Additional observations to assess variability are planned.
We thank the staff at the VLT for the rapid execution of these observations.
GCN Circular 43413
Subject
Konus-Wind detection of GRB 260114A
Date
2026-01-15T12:44:01Z (4 months ago)
From
Anna Ridnaia at Ioffe Institute <ridnaia@mail.ioffe.ru>
Via
Web form
A. Ridnaia, D. Frederiks, A. Lysenko, D. Svinkin,
A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:
The short-duration GRB 260114A
(Fermi-GBM detection: Fermi GBM Team, GCN 43395;
Bissaldi, GCN 43400;
Swift-BAT detection: Eyles-Ferris et al., GCN 43396;
GECAM-B observation: Ren et al., GCN 43402;
SVOM/GRM observation: Wang et al., GCN 43404)
triggered Konus-Wind at T0=42030.729 s UT (11:40:30.729).
The burst light curve shows a single pulse
which starts at ~T0 s and has a total duration of ~0.3 s.
The emission is seen up to ~2 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB260114_T42030/
As observed by Konus-Wind, the burst
had a fluence of 5.12(-0.25,+0.25)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0+0.024 s,
of 2.76(-0.33,+0.33)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum of the burst
(measured from T0 to T0+0.256 s)
is best fit in the 20 keV - 10 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = 0.56(-0.15,+0.16)
and Ep = 502(-25,+26) keV (chi2 = 36/34 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -3.4
(chi2 = 36/33 dof).
Assuming the redshift z=0.524 (Yang et al., GCN 43410)
and a standard cosmology model with H_0 = 67.3 km/s/Mpc,
Omega_M = 0.315, and Omega_Lambda = 0.685 (Planck Collaboration, 2014),
we estimate the following rest-frame parameters:
the isotropic energy release E_iso is 3.86(-0.19,+0.19)x10^51 erg,
the peak luminosity L_iso is 3.17(-0.38,+0.38)x10^52 erg/s,
and the rest-frame peak energy of the time-integrated spectrum,
Ep,i, is 765(-38,+40) keV.
With the obtained estimates, the position of GRB 260114A in both Eiso-Ep,z and Liso-Ep,z planes
is consistent with short-hard (Type I) GRB population,
see http://www.ioffe.ru/LEA/GRBs/GRB260114_T42030/GRB260114A_rest_frame.pdf
All the quoted errors are at the 68% confidence level.
All the quoted values are preliminary.
GCN Circular 43412
Subject
GRB 260114A: Swift-XRT refined Analysis
Date
2026-01-15T11:55:38Z (4 months ago)
From
Phil Evans at U of Leicester <pae9@star.le.ac.uk>
Via
email
A.P. Beardmore (U. Leicester), B. Sbarufatti (INAF-OAB), C. Salvaggio
(INAF-OAB), M. Ferro (INAF-OAB), J.A. Kennea (PSU), D.N. Burrows (PSU),
S. Lanava (PSU), J.P. Osborne (U. Leicester) and P.A. Evans report on
behalf of the Swift-XRT team:
We have analysed 4.9 ks of XRT data for GRB 260114A, from 107 s to 33.3
ks after the trigger. The data comprise 9 s in Windowed Timing (WT)
mode (taken while Swift was slewing), with the remainder in Photon
Counting (PC) mode. The best available XRT position (using the
promptly downlinked event data, the XRT-UVOT alignment and matching
UVOT field sources to the USNO-B1 catalogue) is RA, Dec = 74.59789,
-8.01441 which is equivalent to:
RA (J2000): 04h 58m 23.49s
Dec(J2000): -08d 00' 51.9"
with an uncertainty of 3.2 arcsec (radius, 90% confidence).
The light curve can be modelled with a power-law decay with a decay
index of alpha=2.9 (NaN, NaN).
A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.7 (+0.8, -0.6). The
best-fitting absorption column is 4.9 (+8.1, -3.9) x 10^21 cm^-2, in
excess of the Galactic value of 5.7 x 10^20 cm^-2 (Willingale et al.
2013). The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum is 4.9 x 10^-11 (6.9 x 10^-11) erg
cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 4.9 (+8.1, -3.9) x 10^21 cm^-2
Galactic foreground: 5.7 x 10^20 cm^-2
Excess significance: 1.9 sigma
Photon index: 1.7 (+0.8, -0.6)
If the light curve continues to decay with a power-law decay index of
2.9, the count rate at T+24 hours will be 1.2 x 10^-8 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.9 x
10^-19 (8.2 x 10^-19) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
https://www.swift.ac.uk/xrt_products/01440319.
This circular is an official product of the Swift-XRT team.
GCN Circular 43411
Subject
GRB 260114A: 6 GHz VLA observations
Date
2026-01-15T11:11:29Z (4 months ago)
From
Roberto Ricci at INAF-IRA <ricci@ira.inaf.it>
Via
Web form
R. Ricci, M. Yadav, E. Troja (U Rome) report:
We observed the short-duration GRB 260114A detected by Fermi-GBM (Fermi team GCN 43395), Swift/BAT (Eyles-Ferris et al. GCN 43396), GECAM-B (Ren et al., GCN 43402) and SVOM/GBM (SVOM/GRM team, GCN 43404) with Very Large Array in C-band at the centre frequency of 6 GHz with a bandwidth of 4 GHz on Jan 15th 2025, 15.5 hours after the burst.
After reducing the data using the CASA version v6.6.1 with standard procedures no source was detected inside the Swift/XRT error circle (Eyles-Ferris et al., GCN 43396) down to a 3-sigma flux density upper limit of about 30 microJy/beam.
We thank the VLA staff for promptly executing the observations.
GCN Circular 43410
Subject
GRB 260114A: VLT/X-shooter redshift of the putative host galaxy
Date
2026-01-15T09:07:12Z (4 months ago)
From
Yu-Han Yang at University of Rome Tor Vergata <yyang@roma2.infn.it>
Via
Web form
Yu-Han Yang (U Rome), Eleonora Troja (U Rome), and Rosa Becerra (UNAM) report:
We observed the field of GRB 260114A, detected by Swift (Eyles-Ferris et al., GCN 43396), Fermi (Fermi GBM Team, GCN 43395; E. Bissaldi et al. GCN 43400), GECAM-B (Ren et al., GCN 43402) and SVOM/GBM (SVOM/GRM team, GCN 43404), with the X-Shooter spectrograph on the ESO VLT UT3 (Melipal). Observations started at 13.8 hours after the GRB trigger, with a total exposure time of 4 × 600 s at an average airmass of ~1.1.
In the acquisition image no new uncatalogued source is detected. Several extended sources, also reported in the DESI Legacy Survey, are visible within the XRT error circle. For the brightest object with r~21.1 AB mag we derive a chance alignment of P_cc ~ 4%. Based on a preliminary analysis, we identify multiple emission features corresponding to Hα, Hβ, and the [O II] doublet with a common redshift of z~0.524.
We thank the staff at the VLT, especially T. Rivinius and L. Sbordone, for the rapid execution of these observations.
GCN Circular 43409
Subject
GRB 260114A : MITSuME Akeno optical upper limits
Date
2026-01-15T06:59:47Z (4 months ago)
From
Ichiro Takahashi at Science Tokyo <itakahashi@hp.phys.titech.ac.jp>
Via
Web form
I. Takahashi, M. Sasada, H. Hagio, A. Ochi, Y. Kubo, R. Kato, H. Seki, S. Joshima, Y. Yatsu and N. Kawai (Science Tokyo) report on behalf of the MITSuME collaboration:
We observed the field of GRB 260114A detected by Fermi (Fermi GBM team, GCN 43395) and Swift (Eyles-Ferris et al., GCN 43396) with the optical three-color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50-cm telescope Akeno.
The observation started at 2026-01-14 11:41:18 UT (52 seconds after the trigger). We stacked the images taken under good conditions. We did not detect any obvious point sources within the Swift/XRT error region (Eyles-Ferris et al., GCN 43396). We obtained the 5-sigma limits of the stacked images as follows:
T0+[sec] | MID-UT | T-EXP[sec] | 5-sigma limits
------------------------------------------------------------------------------------------------
228 | 2026-01-14 11:44:14 | 140 | g'>17.5, Rc>17.5, Ic>17.2
4089 | 2026-01-14 12:48:35 | 4260 | g'>19.8, Rc>19.9, Ic>19.5
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the trigger
T-EXP: Total exposure time
We used the PS1 catalog for flux calibration. The catalog magnitudes in PS1 g, r and i bands were converted to our g', Rc and Ic band magnitudes following Tonry et al. (2012), Table 6. The magnitudes are expressed in the AB system. The images were processed in real-time through the MITSuME GPU reduction pipeline (Niwano et al. 2021, PASJ; https://github.com/MNiwano/Eclaire).
GCN Circular 43408
Subject
GRB 260114A: COLIBRÍ optical upper limits
Date
2026-01-15T04:42:41Z (4 months ago)
From
Camila Angulo Valdez at UNAM <camiangulo@astro.unam.mx>
Via
Web form
Camila Angulo (UNAM), Jean-Grégoire Ducoin (CPPM), Rosa L. Becerra (UNAM), Stéphane Basa (UAR Pytheas), William H. Lee (UNAM), Alan M. Watson (UNAM), Edilberto Aguilar-Ruiz (UNAM), Jean-Luc Atteia (IRAP), Dalya Akl (NYUAD), Sarah Antier (IJCLAB), Nathaniel R. Butler (ASU), Damien Dornic (CPPM), Francis Fortin (IRAP), Leonardo García García (UNAM), Ramandeep Gill (UNAM), Noémie Globus (UNAM), Asuka Kuwata (UNAM), Nikos Mandarakas (LAM), Diego López-Cámara (UNAM), Francesco Magnani (CPPM), Enrique Moreno Méndez (UNAM), Margarita Pereyra (UNAM), Ny Avo Rakotondrainibe (LAM), Fredd Sánchez Álvarez (UNAM), Benjamin Schneider (LAM) and Antonio de Ugarte Postigo (LAM):
We imaged the field of the Swift GRB 260114A (Eyles-Ferris et al., GCN Circ. 43396), also detected by Fermi (Fermi GBM Team, GCN Circ. 43395; E. Bissaldi et al. GCN Circ. 43400), GECAM-B (Ren et al., GCN Circ. 43402), SVOM/GBM (SVOM/GRM team, GCN Circ. 43404), using the DDRAGO two-channel wide-field imager on the COLIBRÍ telescope. We observed from 2026-01-15 02:01 to 03:22 UTC (from 14.3 to 15.7 hours after the trigger) and obtained 63 minutes of simultaneous exposure in the r and z filters.
The data were reduced and coadded with the COLIBRÍ ASU pipeline and analysed with STDWeb (Karpov 2025). The photometry was calibrated using nearby stars from the PanSTARRS DR1 catalog, is in the AB system, and is not corrected for Galactic extinction.
After performing image subtraction of our stacked images against Legacy Survey (Dey et al. 2019) using STDWeb (Karpov 2025), we do not detect any new source at the XRT source position (Eyles-Ferris et al., GCN Circ. 43396) or the optical counterpart previously reported by GMG (Li et al., GCN Circ. 43398) and the Mondy observatory (Volnova et al., GCN Circ. 43401) down to the following 3-sigma limits:
r > 24.1,
z > 22.7.
These upper limits are consistent with later reports from MASTER (Lipunov et al., GCN Circ. 43403), NOT (Corcoran et al., GCN Circ. 43406) and TNG (Brivio et al., GCN Circ. 43407).
We thank the staff of the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir and the COLIBRÍ and DDRAGO engineering teams.
COLIBRÍ is an astronomical observatory developed and operated jointly by France (AMU, CNES and CNRS) and Mexico (UNAM and SECIHTI). It is located at the Observatorio Astronómico Nacional on the Sierra de San Pedro Mártir, Baja California, Mexico.
GCN Circular 43407
Subject
GRB 260114A: TNG NIR upper limit
Date
2026-01-15T01:04:21Z (4 months ago)
From
Riccardo Brivio at INAF-OAB <riccardo.brivio@inaf.it>
Via
Web form
R. Brivio, P. D'Avanzo (INAF-OAB), D. B. Malesani (DAWN/NBI & Radboud Univ.), L. Izzo (INAF-OACn), A. Melandri (INAF-OAR), M. Pedani (INAF-TNG) report on behalf of the CIBO collaboration:
We observed the field of GRB 260114A detected by Fermi/GBM (Fermi GBM team, GCN 43395), Swift/BAT (Eyles-Ferris et al., GCN 43396), GECAM-B (Ren et al., GCN 43402), and SVOM/GRM (Wang et al., GCN 43404) with the Italian 3.6m TNG telescope, located in the Canary Islands (Spain), equipped with the near-infrared camera NICS in imaging mode. A series of images were obtained with the H filter on 2026-01-14 at a mid-time of about 10.0 hours after the burst.
The optical counterpart reported by Li et al. (GCN 43398) and Volnova et al. (GCN 43401) is not detected within the Swift/XRT error circle. We obtain a 3-sigma limiting magnitude of H > 20.6 (Vega; calibrated against the 2MASS catalogue).
GCN Circular 43406
Subject
GRB 260114A: NOT optical observations
Date
2026-01-14T21:40:44Z (4 months ago)
From
Gregory Corcoran at University College Dublin <gregory.corcoran@ucdconnect.ie>
Via
Web form
G. Corcoran (UCD), A. Martin-Carrillo (UCD), A. Saccardi (CEA/Irfu), D. B. Malesani (DAWN/NBI and Radboud), K. Valeckas (NOT & NBI) report on behalf of a larger collaboration:
We observed the field of GRB 260114A detected by Fermi/GBM (Fermi GBM team, GCN 43395), Swift/BAT (Eyles-Ferris et al., GCN 43396), GECAM-B (Ren et al., GCN 43402), and SVOM/GRM (Wang et al., GCN 43404) with the Nordic Optical Telescope (NOT) equipped with the ALFOSC camera.
Our observations consisted of 8 x 300 s exposures in SDSS-r and 5 x 200 s in SDSS-z, starting on Jan 14 2026 at 19:32:39 UT (7.87 hr after the trigger).
After performing image subtraction against Legacy Survey using PyZOGY on the stacked images, we do not detect the optical counterpart reported by Li et al. (GCN 43398) and Volnova et al. (GCN 43401) within the Swift/XRT uncertainty region. We obtain the following 3 sigma upper limits in AB magnitudes:
r > 24.0 (mid-time of 8.66 hr after the trigger)
z > 22.2 (mid-time of 8.30 hr after the trigger)
calibrated against nearby stars from the Pan-STARRS catalog, and not corrected for Galactic extinction.
GCN Circular 43404
Subject
GRB 260114A: SVOM/GRM observation of a short burst
Date
2026-01-14T17:52:21Z (4 months ago)
From
Chenwei Wang at IHEP <cwwang@ihep.ac.cn>
Via
Web form
SVOM/GRM team: Chen-Wei Wang, Wen-Jun Tan, Yang-Zhao Ren, Zheng-Hang Yu, Shi-Jie Zheng, Yue Huang, Shao-Lin Xiong, Shuang-Nan Zhang (IHEP)
SVOM/ECLAIRs team: Maria-Grazia Bernardini (INAF-OAB, LUPM)
Report on behalf of the SVOM team:
SVOM/GRM was triggered in-flight by GRB 260114A (SVOM trigger reference: sb26011401) at 2026-01-14T11:40:26.400 (T0), which is also detected by Fermi/GBM (Fermi GBM team, GCN #43395), Swift/BAT (R. A. J. Eyles-Ferris et al., GCN #43396) and GECAM-B (Ren et al., GCN #43402).
With the event-by-event data downloaded through the X-band ground station, the GRM light curve shows that this burst consists of a single pulse with a T90 of 0.38 +0.06/-0.04 s in the 15-5000 keV band.
The SVOM/GRM light curve can be found here:
https://www.bursthub.cn//admin/static/svgrb260114A.png
In addition, the position of this burst, as determined by Swift/BAT (RA = 74.602, Dec = -7.994, Error = 3.3 arcseconds, GCN #43396), is located at about 94 degrees from the SVOM optical axis, which is outside the ECLAIRs field of view.
With this localization, the time-averaged spectrum from T0-0.12 to T0+0.3 s is best fitted by a power law function with an exponential high-energy cutoff. The power law index is -0.43 +0.13/-0.11 and the cutoff energy, parameterized as Epeak, is 954 +134/-120 keV. The event fluence (10-1000 keV) in this time interval is (6.72 +0.23/-0.22)E-06 erg/cm^2.
The localization of GRB 260114A in the 'Amati' relation diagram is shown at: https://www.bursthub.cn//admin/static/svgrb260114A_amati.png
The Space Variable Objects Monitor (SVOM) is a China-France joint mission led by the Chinese National Space Administration (CNSA, China), National Center for Space Studies (CNES, France) and the Chinese Academy of Sciences (CAS, China), which is dedicated to observing gamma-ray bursts and other transient phenomena in the energetic universe. GRM is developed by the Institute of High Energy Physics (IHEP) of CAS.
The SVOM/GRM point of contact for this burst is: Chen-Wei Wang (IHEP) (cwwang@ihep.ac.cn)
GCN Circular 43403
Subject
Swift GRB 260114A: Global MASTER-Net observations report
Date
2026-01-14T17:42:32Z (4 months ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
Via
email
V.Lipunov, E.Gorbovskoy, A.Kuznetsov, K.Zhirkov, I.Panchenko, N.Tiurina, P.Balanutsa, V.Topolev, D.Vlasenko,
G.Antipov, A.Sankovich, Yu.Tselik, Ya.Kechin, V.Senik, A.Chasovnikov, K.Labsina, I. Gorbunov (Lomonosov MSU),
O.Gress, N.Budnev (ISU),
C.Francile, F. Podesta, R.Podesta, E. Gonzalez (Observatorio Astronomico Felix Aguilar (OAFA),
A. Tlatov, D. Dormidontov (Kislovodsk Solar Station of the Pulkovo Observatory),
A.Sosnovskij (CrAO),
A. Gabovich, V.Yurkov (Blagoveschensk Educational StateUniversity),
D.Buckley (SAAO),
R.Rebolo (The Instituto de Astrofisica de Canarias),
L.Carrasco, J.R.Valdes, V.Chavushyan, V.M.Patino Alvarez, J.Martinez,
A.R.Corella, L.H.Rodriguez (INAOE, Guillermo Haro Astrophysics Observatory)
MASTER-Tunka robotic telescope [1] located in Russia (Applied Physics Institute, Irkutsk State University) was pointed to the Swift GRB 260114A ( R. A. J. Eyles-Ferris et al., GCN 43396) errorbox 13094 sec after notice time and 13137 sec after trigger time at 2026-01-14 15:19:23 UT, with upper limit up to 20.0 mag. The observations began at zenith distance = 60 deg. The sun altitude is -52.6 deg.
The galactic latitude b = -28 deg., longitude l = 207 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=3101880
We obtain a following upper limits.
Tmid-T0 | Site |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________
13167 | MASTER-Tunka | C | 60 | 19.4 |
13227 | MASTER-Tunka | C | 180 | 20.0 | Coadd
13241 | MASTER-Tunka | C | 60 | 15.5 |
13241 | MASTER-Tunka | C | 60 | 19.2 |
13313 | MASTER-Tunka | C | 60 | 19.1 |
13389 | MASTER-Tunka | C | 60 | 14.9 |
13389 | MASTER-Tunka | C | 60 | 19.1 |
13449 | MASTER-Tunka | C | 180 | 19.8 | Coadd
13461 | MASTER-Tunka | C | 60 | 15.2 |
13461 | MASTER-Tunka | C | 60 | 19.2 |
13536 | MASTER-Tunka | C | 60 | 17.8 |
13536 | MASTER-Tunka | C | 60 | 19.0 |
13611 | MASTER-Tunka | C | 60 | 18.7 |
13611 | MASTER-Tunka | C | 60 | 19.3 |
14458 | MASTER-Tunka | C | 60 | 19.1 |
14458 | MASTER-Tunka | C | 60 | 18.6 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
[1] - V.M. Lipunov, V.G. Kornilov, E.S. Gorbovskoy, N.A. Tiurina & A.S.Kuznetsov, 2023, Astronomical Robotic Networks and Operative Multichanel Astrophysics, Lomonosov MSU PRESS, 591pp.
http : // www.pereplet.ru/lipunov/625.html
GCN Circular 43402
Subject
GRB 260114A: GECAM-B observation of a short burst
Date
2026-01-14T17:19:48Z (4 months ago)
From
renyz16607@163.com
Via
Web form
Yang-Zhao Ren, Chen-Wei Wang, Wen-Jun Tan, Zheng-Hang Yu, Shao-Lin Xiong (IHEP) report on behalf of GECAM team:
GECAM-B was triggered in-flight by GRB 260114A, at 2026-01-14T11:40:26.350 UTC (denoted as T0), which is also detected by Fermi/GBM (Fermi GBM team, GCN #43395), and Swift/BAT (Eyles-Ferris et al., GCN #43396).
According to the GECAM-B light curves in about 70-6000 keV, this burst mainly consists of a pulse with a duration (T90) of 0.38 +0.18/-0.08 s.
The GECAM-B light curve can be found here:
https://www.bursthub.cn//admin/static/gecambgrb260114A.png
The time-averaged spectrum from T0-0.1 to T0+0.4 s is best fitted by a power law function with an exponential high-energy cutoff. The power law index is -0.26 +0.16/-0.30 and the cutoff energy, parameterized as Epeak, is 700 +93/-96 keV. The event fluence (10-1000 keV) in this time interval is (5.03 +0.34/-0.31)E-06 erg/cm^2.
The 'Amati' relation diagram of GRB 260114A is shown at:
https://www.bursthub.cn//admin/static/gecambgrb260114A_amati.png
Gravitational wave high-energy Electromagnetic Counterpart All-sky Monitor (GECAM) mission originally consists of two micro-satellites (GECAM-A and GECAM-B) launched in Dec. 2020. As the third member of GECAM constellation, GECAM-C was launched onboard SATech-01 experimental satellite in July 2022. GECAM mission is funded by the Chinese Academy of Sciences (CAS).
GCN Circular 43401
Subject
GRB 260114A: Mondy optical observations
Date
2026-01-14T16:57:54Z (4 months ago)
From
Alexei Pozanenko at IKI, Moscow <grb.alex@gmail.com>
Via
email
A. Volnova (IKI), A. Pozanenko (IKI), E. Klunko (ISTP), N. Pankov
(HSE, IKI) report on behalf of IKI-GRB-FuN:
We observed the field of GRB 260114A (Eyles-Ferris et al., GCN 43396;
Fermi GBM team, GCN 43395; Bissaldi et al., GCN 43400) with the
AZT-33IK 1.5m telescope of the Mondy observatory starting on
2026-01-14 (UT) 12:17:27 in R filter. Within the Swift/XRT error
circle (Eyles-Ferris et al., GCN 43396) we detect the optical
counterpart (Li et al., GCN 43398). Preliminary photometry is the
following:
Date UT start t-T0 Exp. Filter Obj. Err. UL
Site/Telescope
(mid,days) (n*s) (3sigma)
2026-01-14 12:17:27 0.08360 37*120 R 20.41 0.15 21.6
The photometry is calibrated using USNO-B1.0 stars and is not
corrected for the Galactic extinction.
GCN Circular 43400
Subject
GRB 260114A: Fermi GBM observation
Date
2026-01-14T16:32:46Z (4 months ago)
From
Elisabetta Bissaldi at Politecnico and INFN Bari <elisabetta.bissaldi@ba.infn.it>
Via
Web form
E. Bissaldi (Politecnico and INFN Bari)
reports on behalf of the Fermi GBM Team:
"At 11:40:26.31 UT on 14 January 2026, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 260114A (trigger 790083631 / 260114486),
which was also detected by the Swift/BAT (Eyles-Ferris et al. 2026, GCN 43396).
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time is 70 degrees.
The GBM light curve consists of a bright emission episode
with a duration (T90) of about 320 ms (50-300 keV).
The time-averaged spectrum from T0-0.064 s to T0+0.384 s is
best fit by a power law function with an exponential
high-energy cutoff. The power law index is -0.07 +/- 0.06 and
the cutoff energy, parameterized as Epeak, is 583 +/- 25 keV.
The event fluence (10-1000 keV) in this time interval is
(4.87 +/- 0.12)E-06 erg/cm^2. The 64-ms peak photon flux measured
starting from T0+0.064 s in the 10-1000 keV band
is 35.9 +/- 1.4 ph/s/cm^2.
A Band function fits the spectrum equally well
with Epeak = 575 +/- 29 keV, alpha = -0.06 +/- 0.06, and beta = -3.5 +/- 0.6.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html
For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"
GCN Circular 43398
Subject
GRB 260114A: GMG Optical Observation
Date
2026-01-14T13:39:46Z (4 months ago)
From
Rui-Zhi Li at Yunnan Observatories, CAS <liruizhi@ynao.ac.cn>
Via
Web form
R.-Z. Li, J. Mao, B.-T. Wang, F.-F. Song, Y. Wang, J.-G. Wang and B. Wang (YNAO, CAS) report:
We observed the field of GRB 260114A (Eyles-Ferris et al., GCN 43396; Fermi GBM team, GCN 43395; T0 at 2026-01-14T11:40:26) using the GMG-2.4m telescope at the Lijiang Observatory. The observation began at 2026-01-14T12:18:52, about 0.64 hours after the trigger.
We detected an optical source within the Swift/XRT error circle (Eyles-Ferris et al., GCN 43396).
The preliminary analysis results for this source are presented below.
+---------------+------------+----------+--------------+----------------+
| Tmid-T0 [h] | Exp. [s] | Filter | Mag | 5-sigma U.L. |
+===============+============+==========+==============+================+
| 0.81 | 1200 | r | 21.19 ± 0.06 | 22.6 |
+---------------+------------+----------+--------------+----------------+
We note that an extended galaxy (R.A., Dec. = 04:58:23.41, −08:00:49.6; r = 21.47 mag in the Pan-STARRS DR2 image) is located within the Swift/XRT error circle. Three objects within the Swift/XRT error circle have photometric redshifts of z ~ 0.5 in the DESI Legacy Surveys.
Given the poor seeing conditions at the Lijiang Observatory, no additional candidate sources in our image were found within the Swift/XRT error circle.
The given magnitudes are derived based on calibration against Pan-STARRS1 field stars, and are not corrected for the expected Galactic foreground extinction, corresponding to a reddening of E(B-V) = 0.0685 mag in the direction of the optical source (Schlafly & Finkbeiner 2011).
GCN Circular 43396
Subject
GRB 260114A: Swift detection of a short burst
Date
2026-01-14T11:55:28Z (4 months ago)
From
Rob Eyles-Ferris at U of Leicester <raje1@leicester.ac.uk>
Via
email
R. A. J. Eyles-Ferris (U Leicester), J. A. Kennea (PSU),
H. A. Krimm (NSF), N. P. M. Kuin (UCL-MSSL), K. L. Page (U Leicester)
and B. Sbarufatti (INAF-OAB) report on behalf of the Neil Gehrels
Swift Observatory Team:
At 11:40:26 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 260114A (trigger=1440319). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 74.602, -7.994 which is
RA(J2000) = 04h 58m 25s
Dec(J2000) = -07d 59' 37"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a single-peaked
structure with a duration of about 0.5 sec. The peak count rate
was ~16000 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 11:42:28.4 UT, 122.2 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 74.59830, -8.01433
which is equivalent to:
RA(J2000) = 04h 58m 23.59s
Dec(J2000) = -08d 00' 51.6"
with an uncertainty of 3.3 arcseconds (radius, 90% containment). This
location is 74 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at https://www.swift.ac.uk/sper. We
cannot determine whether the source is fading at the present time.
A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 5.72
x 10^20 cm^-2 (Willingale et al. 2013).
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 126 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag.
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.080.
Burst Advocate for this burst is R. A. J. Eyles-Ferris (raje1 AT leicester.ac.uk).
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/)
GCN Circular 43395
Subject
GRB 260114A: Fermi GBM Final Real-time Localization
Date
2026-01-14T11:51:03Z (4 months ago)
From
Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>
Via
email
The Fermi GBM team reports the detection of a likely SHORT GRB
At 11:40:26 UT on 14 Jan 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260114A (trigger 790083631.309942 / 260114486).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 74.1, Dec = -15.2 (J2000 degrees, equivalent to J2000 04h 56m, -15d 11'), with a statistical uncertainty of 1.7 degrees.
The angle from the Fermi LAT boresight is 63.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260114486/quicklook/glg_skymap_all_bn260114486.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260114486/quicklook/glg_healpix_all_bn260114486.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260114486/quicklook/glg_lc_medres34_bn260114486.gif