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.
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.
Advanced Search Examples (click to copy):
subject:"Swift"body:"GRB"submitter:"Judith Racusin"15275 results found.
- GRB 251108C: AstroSat CZTI detection
- LIGO/Virgo/KAGRA S251112cm: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo/KAGRA S251112cm: Upper limits from Fermi-GBM Observations
- GRB 251111A: Swift-XRT observations
- GRB 251111A: EP-FXT counterpart detection
- GRB 251013C: Chandra X-ray observations and jet break detection
- GRB 251111A: SVOM/VT optical observations with VHF data
- GRB 251111A: KAIT optical upper limit
- GRB 251111A: LCO optical observation
- GRB 251111A: SVOM/COLIBRÍ (FM-GFT) optical counterpart detection
- GRB 251111A: SVOM detection of a soft burst
- GRB 251105B: Insight-HXMT/HE detection
- GRB 251106B: Insight-HXMT detection
- LIGO/Virgo/KAGRA S251108fi: DDOTI Optical Candidate
- GRB 251105A: AstroSat CZTI detection
- LIGO/Virgo/KAGRA S251108fi: One counterpart neutrino candidate from IceCube neutrino searches
- IceCube-Cascade 251107A: Upper limits from a search for additional neutrino events in IceCube
- GRB 251102B: SVOM/GRM observation
- The EP-WXT trigger 01709248051 is likely a flaring star
- GRB 251106A: SVOM/COLIBRÍ (FM-GFT) fading of the optical counterpart
- GRB 251106B: SVOM/GRM observation of a short burst
- GRB 251106A: Kilonova-Catcher optical upper limit
- GRB 251106A: SVOM detection of a burst
- GRB 251103B: AstroSat CZTI detection
- GRB 251025C: TERI Gamma-ray detection
- GRB 251016B: TERI Gamma-ray detection
- GRB 251016A: TERI Gamma-ray detection of a short burst
- GRB 250920C: TERI Gamma-ray detection
- EP251102a: Xinglong 2.16-m clear-band observations of the optical counterpart
- GRB 251105A: Fermi GBM Observation
- LIGO/Virgo/KAGRA S251031dw: Candidates from the Zwicky Transient Facility
- GRB 251105A: Swift/BAT-GUANO localization skymap of a burst
- GRB 251105B: AstroSat CZTI detection of a short burst with extended emission
- GRB 251023A: SVOM/ECLAIRs detection of a burst through targeted search
- GRB 251105B: SVOM/GRM observation of a possible short burst with extended emission
- GRB 251103B: Fermi GBM observation
- GRB 251104A: SVOM detection of a burst
- GRB 251028A: Insight-HXMT/HE detection
- EP251102a: update of EP-FXT follow-up observation
- GRB 251103A: Insight-HXMT detection
- GRB 251103B: Nanshan/HMT optical upper limit
- GRB 251013C: 7DT detection and Medium-band SED of Afterglow
- GRB 251103A: Kilonova-Catcher optical afterglow detection
- GRB 251103A: Fermi GBM Observation
- GRB 251103A: SVOM/GRM observation
- GRB 251103A: Swift-XRT afterglow detection
- GRB 251103A: SVOM/COLIBRÍ (FM-GFT) optical observations
- EP251102a: Einstein Probe detection of a fast X-ray transient
- GRB 251103A: LCO optical observation
- GRB 251102A: AstroSat CZTI detection
- GRB 251026A: SVOM/COLIBRÍ (FM-GFT) confirmation of the optical counterpart
- GRB 251103A: BOOTES-2/TELMA optical afterglow
- GRB 251103A: LCO optical afterglow detection
- GRB 251103A: SVOM detection of a bright burst
- GRB 251031A: Fermi GBM Observation
- GRB 251031A: Swift/BAT-GUANO localization skymap of a burst
- Konus-Wind detection of GRB 251028A
- GRB 251025C: SVOM/GRM observation
- GRB 251028A: GECAM-B detection
- GRB 251028A: SVOM/GRM observation
- IceCube-251025A: Two Transient Candidates from the Zwicky Transient Facility
- GRB 251026B: SOAR Classification of GOTO25jgl/SN2025absf as a Type Ia supernova
- GRB 251022A: Swift-XRT confirmation of fading
- GRB 251026B: LBT near-infrared observations
- GRB 250926B: VZLUSAT-2 detection
- GRB 250926A: VZLUSAT-2 detection
- GRB 250925A: VZLUSAT-2 detection
- GRB 251028B: Fermi/GBM observation
- GRB 251028B: Swift/BAT-GUANO localization skymap of a burst
- GRB 251028A: Glowbug gamma-ray detection
- IceCube-251025A: Upper limits from a search for additional neutrino events in IceCube
- Fermi-LAT Gamma-ray Observations of IceCube-251025A
- Konus-Wind detection of GRB 251022A
- GRB 251022A: SVOM/GRM observation
- GRB 251026B: Swift ToO observations
- GRB 251026A/EP251026a: Einstein Probe detection of a fast X-ray transient
- GRB 251027A: LCO optical upper limit
- GRB 251023B / EP251023b: Mondy optical upper limit
- GRB 251025B: Kilonova-Catcher optical afterglow detection
- Konus-Wind detection of GRB 251016A (short/hard)
- GRB 251027A: SVOM detection of a faint burst
- GRB 251025C: AstroSat CZTI detection
- IceCube-251025A: DDOTI Optical Upper Limit
- GRB 251026A: SVOM detection of a long burst
- GRB 251023A: SVOM/GRM observation
- Konus-Wind detection of GRB 251016B
- GRB 251025A (sb25102501): stellar flare confirmed
- GRB 251025B: SVOM/VT optical observations with VHF data
- GRB 251025B: SVOM detection of a burst
- IceCube-251025A - IceCube observation of a high-energy neutrino candidate track-like event
- GRB 251025A (sb25102501): Likely a stellar flare by SVOM/VT
- GRB 251025A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
- GRB 251025A: SVOM detection of a faint burst
- GRB 251023C: Glowbug gamma-ray detection
- GRB 251023B / EP251023b: COLIBRÍ Confirmation of the Fading Nature of the Optical Candidate
- GRB 251022A: COLIBRÍ Further Multi-frequency Optical Observations
- GRB 251023C: AstroSat CZTI detection
- EP251023b/GRB 251023B: JinShan optical observation
- GRB 251022A: Swift-XRT detection of GOTO25iym
- EP251023b/GRB 251023B : Einstein Probe detection of a fast X-ray transient