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').
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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"23687 results found.
- LIGO/Virgo/KAGRA S251112cm: Classification of reported candidates with SOAR/Goodman
- GRB 251116B: SVOM/VT optical upper limit
- LIGO/Virgo/KAGRA S251112cm: WFST follow-up observations and preliminary results
- GRB 251116C: Swift-XRT observations
- GRB 251116D: Glowbug gamma-ray detection
- EP251023a: Assy AZT-20 optical observations
- GRB 251116D: AstroSat CZTI detection
- GRB 251116C: SVOM/VT optical upper limit
- LIGO/Virgo/KAGRA S251116en: Identification of a GW compact binary merger candidate
- LIGO/Virgo/KAGRA S251112cm: Observations with the NSF-DOE Vera C. Rubin Observatory
- GRB 251116B: LCO optical upper limits
- GRB 251116C: LCO optical upper limits
- GRB 251116C: SVOM detection of a burst
- GRB 251116B: SVOM detection of a burst
- LIGO/Virgo/KAGRA S251112cm: GRANDMA observations of the skymap
- LIGO/Virgo/KAGRA S251112cm: AT2025adht follow-up at Maidanak observatory by GRANDMA
- LIGO/Virgo/KAGRA S251112cm: NED Galaxies in the 4-Update Localization Volume
- GRB 251113A: Glowbug gamma-ray detection
- GRB 251113A: AstroSat CZTI detection
- GRB 251112A: Swift-BAT refined analysis
- Konus-Wind detection of GRB 251108C
- Konus-Wind detection of GRB 251103A
- LIGO/Virgo/KAGRA S251112cm: ATLAS targeted observations of the skymap
- LIGO/Virgo/KAGRA S251112cm: Swift XRT observations, 20 X-ray sources
- LIGO/Virgo/KAGRA S251112cm: Candidates from the Zwicky Transient Facility
- LIGO/Virgo/KAGRA S251112cm: TROVE Vetting of TNS Candidates
- GRB 251111A: SVOM/ECLAIRs refined analysis
- GRB 251025B: SVOM/ECLAIRs refined analysis
- LIGO/Virgo/KAGRA S251112cm: ATLAS pre-detections of AT2025adgp and AT2025adgq
- GRB 251108C: AstroSat CZTI detection
- GRB 251112B: MAXI/GSC detection
- LIGO/Virgo/KAGRA S251112cm: Coverage and upper limits from MAXI/GSC observations
- LIGO/Virgo/KAGRA S251112cm: Initial GOTO-South observations
- GRB 251108B: Glowbug gamma-ray detection
- Swift Trigger 1413695: a possible GRB 251112A
- LIGO/Virgo/KAGRA S251112cm: NED Galaxies in the 3-Initial Localization Volume
- LIGO/Virgo/KAGRA S251112cm: Identification of a GW compact binary merger candidate
- GRB 251106B: Glowbug gamma-ray detection of a likely short burst
- GRB 251111A: Swift-XRT observations
- GRB 251111A: EP-FXT counterpart detection
- GRB 251013C: Chandra X-ray observations and jet break detection
- GRB 251111A: KAIT optical upper limit
- GRB 251111A: SVOM/COLIBRÍ (FM-GFT) optical counterpart detection
- GRB 251103B: Swift-BAT refined analysis
- GRB 251106A: Swift/UVOT Upper Limits
- LIGO/Virgo/KAGRA S251108fi: DDOTI Optical Candidate
- GRB 251105A: AstroSat CZTI detection
- LIGO/Virgo/KAGRA S251108fi: One counterpart neutrino candidate from IceCube neutrino searches
- LIGO/Virgo/KAGRA S251108fi: Identification of a GW compact binary merger candidate
- GRB 251102B: SVOM/GRM observation
- LIGO/Virgo/KAGRA S251108dn: Identification of a GW compact binary merger candidate
- The EP-WXT trigger 01709248051 is likely a flaring star
- IPN triangulation of GRB 251105B (possible sGRB with EE)
- GRB 251106A: SVOM/COLIBRÍ (FM-GFT) fading of the optical counterpart
- GRB 251106A: Kilonova-Catcher optical upper limit
- Fermi GBM Sub-Threshold Detection of GRB 251106A
- GRB 251106A: SVOM/COLIBRÍ (FM-GFT) detection of a likely optical counterpart
- 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 251104A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
- GRB 251105B: AstroSat CZTI detection of a short burst with extended emission
- GRB 251023A: SVOM/ECLAIRs detection of a burst through targeted search
- LIGO/Virgo/KAGRA S251105aj: Identification of a GW compact binary merger candidate
- GRB 251103B: Fermi GBM observation
- GRB 251104A: SVOM detection of a burst
- GRB 251103A: Xinglong 2.16m optical detection
- GRB 251103A: KAIT optical observations
- GRB 251013C: 7DT detection and Medium-band SED of Afterglow
- GRB 251103B: MITSuME Akeno optical upper limits
- LIGO/Virgo/KAGRA S251103f: Identification of a GW compact binary merger candidate
- EP251102a: NIR observations with WINTER
- GRB 251103A: J-band detection with WINTER
- GRB 251103A: Kilonova-Catcher optical afterglow detection
- GRB 251103B: Swift detection of a burst
- GRB 251103A: Fermi GBM Observation
- GRB 251103A: Swift-XRT afterglow detection
- GRB 251103A: SVOM/COLIBRÍ (FM-GFT) optical observations
- GRB 251103A: LCO optical observation
- EP251102.890: COLIBRÍ optical counterpart candidate
- GRB 251103A: GOTO optical afterglow detection
- GRB 251102A: AstroSat CZTI detection
- GRB 251026A: SVOM/COLIBRÍ (FM-GFT) confirmation of the optical counterpart
- GRB 251103A: BOOTES-2/TELMA optical afterglow
- LIGO/Virgo/KAGRA S251031cq: Identification of a GW compact binary merger candidate
- Konus-Wind detection of GRB 251028A
- IceCube-251025A: Two Transient Candidates from the Zwicky Transient Facility
- GRB 251022A: Swift-XRT confirmation of fading
- GRB 250926B: VZLUSAT-2 detection
- GRB 250926A: VZLUSAT-2 detection
- GRB 250925A: VZLUSAT-2 detection
- GRB 251026B: Fermi GBM Observation
- GRB 251028B: Glowbug gamma-ray detection
- GRB 251028A: Glowbug gamma-ray detection
- GRB 251028B: CALET Gamma-Ray Burst Monitor detection
- Fermi GRB 251028B: Global MASTER-Net observations report