GCN Circulars
GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"962 results found.
- GRB 260907A: SVOM/GRM observation
- GRB 260909A: SVOM/ECLAIRs refined analysis
- GRB 260909A: SVOM/VT optical upper limits
- GRB 260909A: SVOM/GRM observation
- GRB 260909A: SVOM/C-GFT optical upper limit
- GRB 260909A: SVOM detection of a burst
- GRB 260903A: SVOM/ECLAIRs refined analysis
- GRB 260903A: LCO optical observations
- GRB 260903A: SVOM/VT optical candidate
- GRB 260903A: Retraction of optical counterpart of GCN 45501
- GRB 260903A: LCO optical counterpart detection
- GRB 260903A: SVOM detection of a soft faint burst
- EP260901a: SVOM/VT optical upper limits
- GRB 260829A: SVOM/GRM observation
- GRB 260831B / sb26083106: SVOM/GWAC-F60A/B confirmation of optical variation of nova V* GK Per
- GRB 260831B / sb26083106: SVOM/VT optical variability of V* GK Per
- SVOM trigger sb26083106 is not a GRB
- GRB 260831B: LCO optical upper limits
- GRB 260827A: SVOM/GRM observation
- GRB 260831B: SVOM detection of a possible burst
- GRB 260825A: SVOM/GRM observation of a long burst
- GRB 260818B: SVOM/VT optical upper limit and continuous observations
- GRB 260818B: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
- GRB 260807A: EP-FXT follow-up observations
- GRB 260822A: SVOM/ECLAIRs refined analysis
- GRB 260809A: SVOM/ECLAIRs refined analysis
- GRB 260822A: SVOM/VT optical upper limits
- GRB 260822A: EP/FXT follow-up observations
- GRB 260818A: further EP-FXT observations and X-ray afterglow confirmation
- GRB 260822A: SVOM/VT optical detection of COLIBRÍ candidate
- GRB 260822A: SVOM/COLIBRÍ (FM-GFT) possible optical counterpart candidate
- GRB 260822A: LCO optical upper limits
- GRB 260822A: SVOM detection of a short burst
- GRB 260818B: SVOM/C-GFT optical upper limit
- EP260731a: SVOM/ECLAIRs detection through offline targeted search
- GRB 260818B: SVOM/GRM observation
- GRB 260818B: SVOM/ECLAIRs refined analysis
- GRB 260818A: SVOM/ECLAIRs refined analysis
- GRB 260810A: SVOM/GRM observation
- GRB 260818B: SVOM/COLIBRÍ (FM-GFT) optical upper limit
- GRB 260818B: LCO optical upper limits
- GRB 260818B: SVOM detection of a short burst
- GRB 260818A: LCO optical upper limits
- GRB 260818A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
- GRB 260818A: SVOM possible detection of a long and faint GRB
- EP260806a: SVOM/ECLAIRs detection through targeted search
- GRB 260805D: SVOM/GRM detection of a possible magnetar burst
- EP260812a: SVOM/C-GFT optical upper limit
- EP260812b: SVOM/VT optical observation
- GRB 260808A: SVOM/GRM observation
- GRB 260808B: SVOM/COLIBRÍ (FM-GFT) confirmation of the optical rebrightening
- GRB 260808B: SVOM/VT optical re-brightening at day 3
- GRB 260317A: SVOM/ECLAIRs detection through offline targeted search and its possible association to magnetar 1E 1841-04.5
- GRB 260807A: SVOM/ECLAIRs refined analysis
- GRB 250607A: SVOM/ECLAIRs detection through offline targeted search
- GRB 260809A: SVOM/COLIBRÍ (FM-GFT) optical observation
- GRB 260808B: SVOM/COLIBRÍ (FM-GFT) optical observation
- GRB 260809A: SVOM/VT optical counterpart
- GRB 260808B: SVOM/ECLAIRs refined analysis
- GRB 260809A: SVOM detection of a faint burst
- GRB 260808B: LCO optical observations
- GRB 260808B: SVOM/VT optical afterglow confirmation
- GRB 260808B: SVOM/VT optical candidate from VHF data ( localization correction for GCN 45317 )
- GRB 260808B: SVOM/VT optical candidate from VHF data
- GRB 260808B: SVOM detection of a faint burst
- GRB 260807A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
- GRB 260807A: SVOM possible detection of a faint burst
- EP260806a: SVOM/VT optical observation
- GRB 260708A: LCO further optical observations show supernova features
- GRB 260802A / EP J223759.5+531421: SVOM/VT optical upper limit
- GRB 260802A: SVOM/VT optical upper limits from VHF data
- GRB 260802A: LCO optical upper limits
- GRB 260802A / EP J223759.5+531421: SVOM/COLIBRÍ (FM-GFT) optical upper limit
- GRB 260802A/EP J223759.5+531421: SVOM detection of a possible magnetar burst
- GRB 260727A: EP-FXT further follow-up observations and candidate afterglow
- GRB 260618B: SVOM/VT continued optical observations indicated a steeper and redder decay
- GRB 260727A: SVOM/ECLAIRs refined analysis
- GRB 260726A: SVOM/ECLAIRs refined analysis
- GRB 260726A: EP-FXT follow-up observations
- GRB 260727A: SVOM/GRM observation
- GRB 260727A: EP/FXT follow-up observations
- GRB 260726A: SVOM/VT optical candidate
- GRB 260726A: SVOM ECLAIRs improved position and MXT possible detection of a counterpart
- EP260723a: SVOM/ECLAIRs Upper Limit
- GRB 260727A: LCO optical upper limits
- GRB 260727A: SVOM detection of a bright long burst
- GRB 260726A: SVOM detection of a burst
- GRB 260718A: SVOM/ECLAIRs refined analysis
- EP260723a: SVOM/VT optical observation
- SVOM trigger sb26071506: SVOM/VT confirmation of a stellar flare
- GRB 260718A: LCO optical upper limits
- GRB 260711A: SVOM/GRM observation
- GRB 260710A: SVOM/GRM observation
- GRB 260718A: SVOM/VT optical upper limits
- GRB 260718A: SVOM/VT optical upper limits from VHF data
- GRB 260718A: SVOM detection of a burst
- GRB 260714B: SVOM/GRM observation
- sb26071506: SVOM detection of a X-ray transient
- EP260703a: SVOM/ECLAIRs Upper Limit
- GRB 260619A: SVOM/VT continuous optical observations