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"23446 results found.
- GRB 260114A: 6 GHz VLA observations
- GRB 260114A: VLT/X-shooter redshift of the putative host galaxy
- GRB 260114A : MITSuME Akeno optical upper limits
- GRB 260114A: COLIBRÍ optical upper limits
- GRB 260114A: TNG NIR upper limit
- GRB 260114A: NOT optical observations
- GRB 260114A: SVOM/GRM observation of a short burst
- GRB 260114A: Mondy optical observations
- GRB 260114A: GMG Optical Observation
- GRB 260114A: Swift detection of a short burst
- EP-WXT trigger 01709251266: SVOM/C-GFT confirmation of a stellar flare
- EP260110a: NOT and GTC Optical and Near-Infrared Observations
- EP260110a: TRT optical upper limits
- Konus-Wind detection of GRB 260101A
- GRB 260111A: Swift-XRT observations
- Swift Trigger 1439093: is probably not GRB 260113A
- GRB 260111A: COLIBRÍ optical afterglow candidate
- GRB 251230A: Mondy Optical Observations
- EP260110a: SVOM/VT optical upper limits
- Swift trigger 1436759 is not an astrophysical event
- EP260110a: KAIT optical upper limit
- EP260110a: refined analysis of the EP-WXT and EP-FXT observations
- EP 260110a: COLIBRÍ optical observations
- EP260110a: SVOM/C-GFT upper limit
- EP260110a: Einstein Probe detection of an X-ray transient
- GRB 260109C: LCO optical upper limits
- GRB 260109C: Kilonova-Catcher optical upper limit
- Swift Trigger 1434591: possible GRB 260109C
- GRB 260102A: Swift-XRT afterglow detection
- GRB 260102A: AbAO optical observations
- EP260105b/EP-WXT trigger 01709251028: Einstein Probe detection of an X-ray transient
- EP260105a: FTW optical observations
- EP260104a: FTW optical observations
- GRB 260105A: SVOM/GRM observation
- GRB 260105B: SVOM/GRM observation
- FRB 20251229A: COLIBRÍ optical upper limits
- EP260105a: SVOM/VT optical upperlimit
- FRB 20251229A: A potentially hyperactive repeating fast radio burst source
- EP260105a: refined analysis of the EP-WXT and EP-FXT observations
- EP260105a: LCO Optical Upper limit
- EP260104a: Einstein Probe detection of a fast X-ray transient
- GRB 260101A: COLIBRÍ optical upper limits
- EP260105a: Einstein Probe detection of an X-ray transient
- GRB 260104A: COLIBRÍ optical upper limits
- GRB 251230A/EP-WXT trigger 01709250693: Mephisto optical upper limits
- GRB 260104A: Swift-XRT refined Analysis
- GRB 260104A: Enhanced Swift-XRT position
- GRB 260101A: Swift/UVOT Detection
- GRB 260104A: Swift detection of a burst
- GRB 260101A: COLIBRÍ optical observations
- GRB 260102A: LCO optical upper limits
- GRB 260102A: Swift-XRT observations
- GRB 260102A: SVOM/COLIBRÍ (FM-GFT) optical observations
- EP260101a: refined analysis of the EP-WXT and EP-FXT observations
- GRB 260102A: SVOM detection of a burst
- GRB 260101A: SVOM/GRM observation
- GRB 260101A: Swift-XRT refined Analysis
- GRB 260101A: Enhanced Swift-XRT position
- EP260101a: Einstein Probe detection of an X-ray transient
- GRB 260101A: LCO detection of the optical counterpart
- GRB 260101A: Swift detection of a burst with an optical counterpart
- GRB 251230A: GRANDMA/TAROT Early Detection
- GRB 251230A/EP251230a: Optical upper limit with Kinder observations
- EP251229a: Optical upper limit with Kinder observations
- GRB 251230A: 1.3m DFOT optical upper limit
- GRB 251230A: Swift-XRT refined Analysis
- GRB 251222A: Mondy Optical Observations
- EP251230a / GRB 251230A: refined analysis of the EP-WXT and EP-FXT observations
- GRB 251230A: Swift/UVOT detection
- GRB251230A: 7DT optical upper limits
- GRB 251230A: GOTO optical upper limit
- EP251229a: NOT optical upper limits
- GRB 251230A / EP251230a: SVOM/VT optical observation
- EP251229a: refined analysis of the EP-WXT and EP-FXT observations
- GRB 251230A: Enhanced Swift-XRT position
- GRB 251230A: Early optical counterpart detection by LCO.
- EP-WXT trigger 01709250662 Mephisto and 50cm telescope follow-up
- EP251230a / GRB 251230A: Einstein Probe detection of an X-ray transient
- LIGO/Virgo/KAGRA S251112cm: Candidates from the NSF-DOE Vera C. Rubin Observatory
- EP251229a: Einstein Probe detection of an X-ray transient
- GRB 251230A: Swift detection of a burst with a bright optical counterpart
- GRB 251226A: Glowbug gamma-ray detection
- GRB 251222A/EP251222b: 1.6m Mephisto optical followup
- GRB 251226A: SVOM/GRM observation
- GRB 251222A/EP251222b: Optical detection with Kinder observations
- EP251222a: Optical upper limit with Kinder observations
- GRB 251205A: Kilonova-Catcher optical afterglow detection
- GRB 251222A: AbAO optical observations
- GRB 251222A / EP251222b: Kilonova-Catcher optical afterglow detection
- GRB 251129A / EP251129a: VLA detection of a radio counterpart
- GRB 251222A: ZTSH BVRI optical observations
- GRB 251222A: SVOM/COLIBRÍ (FM-GFT) optical observations
- GRB 251222A: Continued 1.3m DFOT optical observation
- EP251220a: 3.6m DOT optical afterglow detection
- EP251220a: CrAO ZTSh optical observations
- EP251221a: PRIME upper limit
- EP251221a: Liverpool Telescope upper limits
- EP251222a: refined analysis of the EP-WXT and EP-FXT observations
- EP251222b/GRB 251222A: refined analysis of the EP-WXT and EP-FXT observations
- GRB 251222A: Swift-XRT afterglow detection