GCN Circulars
GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.
Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search
To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.
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subject:"Swift"body:"GRB"submitter:"Judith Racusin"- Fermi-LAT Gamma-ray Observations of IceCube-261113A
- EP261114a: NOT Optical Upper Limits
- GRB 261108A: SVOM/ECLAIRs refined analysis
- EP261114a is likely a flaring star
- GRB 261114A: VLT/FORS2 spectroscopic redshift z = 3.716
- iTelescope observations of GRB 260914A
- GRB 261113A: R-band observations with the 1.3m DFOT
- GRB 261113A: SVOM/GRM observation
- EP261115a: Global MASTER-Net observations report
- EP Alert 261114.82: Global MASTER-Net observations report
- EP261114a: Einstein Probe detection of an X-ray transient
- GRB 261113B: Insight-HXMT/HE detection
- EP261115a: Einstein Probe detection of an X-ray transient
- GRB 261113B: Fermi GBM Final Localization
- Optical Observations of GRB 261113A
- GRB 261113A: AZT-20 Assy-Turgen optical observations
- GRB 261114A: NOT optical observations
- GRB 261114A: SVOM/VT optical observations of a plateau after 5 ks
- G261113_D02737: SVOM/GWAC discovers an optical fading source which might be associated to Fermi/GBM trigger 816291960
- IceCube-261113A - IceCube observation of a high-energy neutrino candidate track-like event
- GRB 261113A: SVOM/GWAC bright optical counterpart
- GRB 261114A: SVOM/VT optical afterglow confirmation
- GRB 261114A: Marginal detection with 60cm Panzhihua Telescope
- GRB 261113A: Ondrejov D50 optical observations
- GRB 261113A: SVOM/ECLAIRs refined analysis
- GRB 261114A: SVOM/VT optical detection from VHF data
- Konus-Wind detection of GRB 261113A
- GRB 261114A: SVOM detection of a burst
- GRB 261113A: Liverpool Telescope observations
- GRB 261113A: SVOM/COLIBRÍ (FM-GFT) optical observations
- GRB 261113A: 10.4m GTC spectroscopic confirmation of z = 3.58
- GRB 261113A: Mondy and AbAO optical observations
- GRB 261113A: GRANDMA/NUTTELA-TAO early optical observations
- GRB 261113A: VLT/X-shooter spectroscopic redshift z = 3.580
- GRB 261113A: TNG NIR afterglow detection
- GRB 261113A: NOT optical observations
- SVOM GRB261113.60: Global MASTER-Net OT detection
- GRB 261113A: OHP/T193 optical detections of the afterglow
- GRB 261113A: GROWTH-India Telescope optical observations
- EP261006a: VLA Radio Detection
- GRB 261113A: SVOM/VT optical decay slope
- GRB 261113A: Optical detection with 60cm Panzhihua Telescope
- GRB 261113A: SVOM/VT optical observation from VHF data
- GRB 261113A: Xinglong 2.16m optical afterglow detection
- GRB 261113A : SVOM/GWAC-F60 optical afterglow detection
- GRB 261113A: GMG Optical Observation
- GRB 261113A: JinShan optical afterglow detection
- GRB 261113A: K-band infrared counterpart candidate by the SYSU 80cm infrared telescope
- SVOM GRB261113.60: Global MASTER-Net observations report
- GRB 261111A: GECAM-B observation of a burst
- GRB 261113A: SVOM detection of a bright burst
- EP-WXT trigger 01709322272 : SVOM/C-GFT observations of a stellar flare
- EP261111a: AbAO and Mondy observations, optical afterglow candidate
- EP261105a: Euclid DR1 Archival Observations Reveal Underlying Source
- GRB 261026A: CrAO ZTSh optical observations
- EP Alert 261112.56: Global MASTER-Net observations report
- The EP-WXT trigger 01709322455 is likely a flaring star
- EP261111a: K and J band upper limits by SYSU 80cm infrared telescope
- EP261111a: LCO optical upper limits
- EP261111a: Refined analysis of EP-FXT observations
- GRB 261110A: SVOM/ECLAIRs refined analysis
- The EP-WXT trigger 01709322452 is likely a flaring star
- EP Alert 261112.01: Global MASTER-Net observations report
- EP261105a: ePESSTO+ host galaxy spectroscopic redshift measurement of z=0.0765
- EP261111a: Global MASTER-Net observations report
- Fermi GRB 261111A: Global MASTER-Net observations report
- GRB 261110A: CrAO ZTSh optical observations
- EP261111a: Xinglong optical upper limit
- EP261111a: Einstein Probe detection of an X-ray transient
- GRB 261111A: BALROG localization (Fermi Trigger 816089232 / GRB 261111477)
- GRB 261111A: Fermi GBM Final Real-time Localization
- GRB 261110A: SVOM/COLIBRÍ (FM-GFT) optical observations
- GRB 261110A : MITSuME Akeno optical upper limits
- GRB 261110A: LCO optical upper limits
- GRB 261110A: SAO RAS optical observations
- GRB 261110A: SVOM/VT optical observations
- GRB 261110A: Xinglong 2.16m optical candidate
- SVOM GRB261110.49: Global MASTER-Net observations report
- GRB 261110A : SVOM/GWAC-F60 optical upper limit
- GRB 261110A: SVOM detection of a burst
- GRB 261108C: VLT/HAWK-I J-band upper limits
- EP Alert 261108.92: Global MASTER-Net observations report
- GRB 261108C: EP/FXT follow-up observation
- GRB 261108D: DECam optical detection of candidate afterglow
- GRB 261108D: PRIME near-infrared candidate
- EP261105A: Gemini-South/GMOS Optical Upper Limit
- GRB 261101A: SVOM/GRM observation
- EP Alert 261109.41: Global MASTER-Net observations report
- The EP-WXT trigger 01709322330 is likely a known AGN
- GRB 261108B: Insight-HXMT/HE detection
- EP261105a: Second EP-FXT follow-up observation
- GRB 261108C: SVOM/VT early optical upper limits
- GRB 261108C: LCO optical upper limits
- SVOM GRB261108.99: Global MASTER-Net observations report
- GRB 261108D: SVOM detection of an X-ray transient
- SVOM GRB261108.89: Global MASTER-Net observations report
- GRB 261108C: SVOM detection of a burst
- GRB 261108A: Fermi GBM Observation
- Konus-Wind detection of GRB 261024A
- GRB 261108B: Fermi GBM Final Localization Correction