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"27815 results found.
- GRB 251013C: EP-FXT counterpart detection
- GRB 251013C: AstroSat CZTI detection
- GRB 251011A: Swift/BAT-GUANO arcminute localization of a burst
- GRB 251013D: Swift/BAT-GUANO arcminute localization of a burst
- GRB 251013C: ALMA detection
- GRB 251013C: SVOM/COLIBRÍ (FM-GFT) detection of the optical counterpart
- GRB 251013C: DDOTI detection of the optical afterglow
- Swift GRB 251014A: Global MASTER-Net observations report
- GRB 251014A: Swift detection of a possibly-short burst
- GRB 251014A: Fermi GBM Final Real-time Localization
- GRB 251013C: Swift-XRT counterpart detection
- GRB 251013C: GOTO optical afterglow detection
- GRB 251013C: LCO optical afterglow detection
- GRB 251013C: NOT spectroscopic redshift z = 0.572
- GRB 251013C: LAST detection of optical counterpart
- GRB 251013C: BOOTES-6 early optical detection
- GRB 251013D: Fermi GBM Final Real-time Localization
- GRB 251013C: SVOM detection of a burst
- GRB 251013C: Fermi GBM Final Real-time Localization
- GRB 251003A: Mondy optical upper limit
- GRB 251013B: Fermi GBM Final Real-time Localization
- GRB 251013A: Fermi GBM Final Real-time Localization
- GRB 251011B inspection: MASTER orphan GRB detection
- GRB 251011A: Insight-HXMT detection
- GRB 251011B: Swift/UVOT Upper Limits
- GRB 251012A: Fermi GBM Final Real-time Localization
- GRB 251011B: SVOM/GRM observation
- GRB 251011B: Swift-XRT refined Analysis
- GRB 251011B: Fermi GBM Observation
- GRB 251011B : MASTER optical observations
- GRB 251011C: Fermi GBM Final Real-time Localization
- GRB 251011B: Enhanced Swift-XRT position
- GRB 251010A: AstroSat CZTI detection
- GRB 251011A: AstroSat CZTI detection
- GRB 251011B: Swift detection of a burst
- GRB 251011B: Fermi GBM Final Real-time Localization
- GRB 251011A: Fermi GBM Final Real-time Localization
- GRB 251007B: Swift/UVOT Upper Limits
- GRB 251010A: Fermi GBM Final Real-time Localization
- GRB251007A: Swift/UVOT Detection
- GRB 251009A: GECAM-B detection of a short burst
- GRB 251009A: Insight-HXMT detection of a short burst
- GRB 251009B (short): Glowbug gamma-ray detection
- GRB 251009B: Insight-HXMT detection of a short burst
- GRB 251007A: Swift-BAT refined analysis
- GRB 251007A: SVOM/GRM observation
- GRB 251007A: Insight-HXMT detection
- GRB 251006A: CALET Gamma-Ray Burst Monitor detection
- SVOM/sb25101004: SVOM detection of a stellar flare
- GRB 251009A: Fermi GBM Final Localization
- GRB 250916A: TERI Gamma-ray detection
- GRB 250919A: TERI gamma-ray detection
- GRB 251006A: Fermi GBM Observation
- GRB 251007A: 1.5m OSN and 2.2m CAHA optical follow-up
- IceCube alert 141456_888784 retraction
- GRB 251003A: Fermi GBM Observation
- GRB 251007B: COLIBRÍ optical upper limit
- GRB 251007A: AstroSat CZTI detection
- GRB 251006B/EP251006a: EP-FXT afterglow detection
- GRB 250917B: iTelescope T-26 upper limit
- GRB 251007A: Swift-XRT refined Analysis
- GRB 251007A: Enhanced Swift-XRT position
- GRB 251007B: Swift-XRT refined Analysis
- GRB 251007B: Enhanced Swift-XRT position
- GRB 251007A: NOT optical observations
- GRB 251007A: AKO Optical Upper Limit
- GRB 251007A: CALET Gamma-Ray Burst Monitor detection
- GRB 251006B: Insight-HXMT detection
- GRB 251007A: SVOM/C-GFT optical observations
- GRB 251005C: PRIME J-band upper limit
- Swift GRB 251007B: Global MASTER-Net observations report
- GRB 251007A: Glowbug gamma-ray detection
- Swift GRB 251007A: Global MASTER-Net observations report
- GRB 251007B: SVOM detection of a faint burst
- GRB 251007B: Swift detection of a burst
- GRB 251007A: Swift detection of a burst with an optical counterpart
- GRB 251006A: Swift/BAT-GUANO subthreshold detection of a short burst
- GRB 251005B: Glowbug gamma-ray detection
- GRB 251006B/EP251006a: EP-FXT follow-up observation
- GRB 251006B/EP251006a: EP-WXT detection
- GRB 251005C: SVOM/GRM observation of a likely short GRB
- GRB 251006B: Fermi GBM Final Real-time Localization
- GRB 251006A (short): Glowbug gamma-ray detection
- GRB 251005C: COLIBRÍ optical observations
- GRB 251003A: LAST optical observations
- GRB 251002A: LAST optical observations
- GRB 251006A: Fermi GBM Final Real-time Localization
- GRB 251005C: SVOM/VT optical candidate
- GRB 251005C: AstroSat CZTI detection
- GRB 251005C: Swift/UVOT Upper Limits
- GRB 250902A: MSU cubesats detection
- GRB 251005C: Swift-XRT refined Analysis
- GRB 251005C: Fermi GBM Observation
- Swift GRB 251005A: Global MASTER-Net observations report
- GRB 251005C: Enhanced Swift-XRT position
- GRB 251005C: GOTO optical upper limits
- GRB 251005C: Swift detection of a burst
- GRB 251005B: Fermi GBM Final Real-time Localization
- GRB 251005A: Fermi GBM Final Localization
- GRB 251002A: Insight-HXMT detection