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.
Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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"23619 results found.
- GRB 241228A: Swift/UVOT Upper Limits
- GRB 241228B: GOTO possible optical counterpart candidate
- GRB 241228A: Swift detection of a burst
- LIGO/Virgo/KAGRA S241225c: Two counterpart neutrino candidates from IceCube neutrino searches
- GRB 241223A: GRBAlpha detection
- GRB 241212A: VZLUSAT-2 detection
- GRB 241029A: LCO optical observation
- GRB 241223A: Swift-XRT observations
- LIGO/Virgo/KAGRA S241225v: Identification of a GW compact binary merger candidate
- Fermi trigger No 756678579: Global MASTER-Net observations report
- EP241223a
- GRB 241223A: GOTO optical observations summary
- GRB 241105A: JWST photometric observations of the host galaxy
- EP241217a: e-MERLIN radio observations
- GRB 241209B: host galaxy detection and GTC/OSIRIS+ spectroscopy
- EP241021a: VLA radio detection
- EP241217a: 1.6m Mephisto multi-band optical observations
- GRB 241217a/EP241217B: 1.6m Mephisto optical upper limits
- GRB 241218A: Swift/UVOT Upper Limits
- GRB 241209B: EP-FXT afterglow detection
- Konus-Wind detection of GRB 241204A (short/hard)
- GRB 241218A: Swift-BAT refined analysis
- EP 241217a: Possible J-band detection with WINTER
- GRB 241217A/EP241217B: Fermi-GBM Sub-Threshold Detection
- EP241217a: refined EP-WXT analysis and EP-FXT follow-up observations
- GRB 241217A: refined SVOM/MXT data analysis. Long lasting X-ray emission.
- GRB 241218A: REM optical upper limit
- GRB 241217A/EP241217b: REM optical/NIR upper limits
- EP241217a: REM optical/NIR upper limits
- GRB 241218A: Swift-XRT refined Analysis
- GRB 241218A: NUTTelA-TAO / BSTI Optical Limits
- EP241217a: Xinglong optical follow-up observations
- EP241217b/GRB 241217A: EP detection of the prompt X-ray emssion
- GRB 241217A: GMG Optical Upper Limit
- GRB 241218A: Swift detection of a burst
- GRB 241217A : SVOM/VT optical afterglow detection
- GRB 241217A: Swift-XRT afterglow detection
- EP241217a: Swift-XRT Detection
- EP241217A: Non-detection from Fermi-GBM Observations
- EP241217a: Kinder optical follow-up observations
- GRB 241214A: GRBAlpha detection
- GRB 241213A (EP241213a): GRBAlpha detection
- GRB 241209D: GRBAlpha detection
- EP241217A: LCO optical observations
- The EP-WXT trigger 01709129023 is likely a flaring star
- EP241107a: VLA Radio Observation
- GRB 241213A: Swift-BAT refined analysis
- Konus-Wind detection of GRB 241213A (EP 241213a)
- GRB 241212A: Swift-XRT observations
- The EP-WXT trigger 01709128948 is likely a flaring star
- GRB 241215A: Montarrenti Observatory optical upper limit
- The EP-WXT trigger 01709128921 is likely a flaring star
- GRB 241213B: Swift-XRT observations
- GRB 241209D: CALET Gamma-Ray Burst Monitor detection
- GRB 241209B: SVOM/VT optical continuous fading
- GRB 241213A: SVOM/VT optical candidate
- GRB 241213B: CALET Gamma-Ray Burst Monitor detection
- EP241208a: NOT optical upper limits
- GRB 241213B: MAXI/GSC detection
- GRB 241213A: REM optical/NIR upper limits
- GRB 241213A: SAO RAS optical upper limit
- GRB 241212A : SVOM/VT bright optical afterglow
- GRB 241212A: AstroSat CZTI detection
- GRB 241209B: GRANDMA/TRT upper limit
- GRB 241207A: TSHAO Zeiss-1000 optical observations
- GRB 241212A: SVOM detection of a bright long burst
- Konus-Wind detection of GRB 241209B
- GRB 241207A: EIRSAT-1 GMOD Detection
- GRB 241209B: GRBAlpha detection
- GRB 241206C: GRBAlpha detection
- GRB 241209D: REM optical/NIR upper limits
- Konus-Wind detection of GRB 241209D
- GRB 241209B: Swift-XRT afterglow detection
- LIGO/Virgo/KAGRA S241210fu: Identification of a GW compact binary merger candidate
- EP241208a: Optical upper limit with Kinder observations
- GRB 241209D: AstroSat CZTI detection
- GRB 241209B: SVOM/VT afterglow detection
- LIGO/Virgo/KAGRA S241210cw: Identification of a GW compact binary merger candidate
- GRB 241209D: Swift-XRT refined Analysis
- GRB 241209D: Fermi GBM Observation
- GRB 241209D: COLIBRÍ detection of the afterglow
- GRB 241209A: COLIBRÍ Optical Upper Limit
- GRB 241209A: GRANDMA/TAROT upper limit
- GRB 241209B: BOOTES-5 optical upper limit
- Swift GRB 241209D: Global MASTER-Net observations report
- LIGO/Virgo/KAGRA S241102br: continued GRAWITA observations and detection of an optical transient (AT2024adip)
- GRB 241209A: REM optical/NIR observations
- GRB 241209D: Swift detection of a burst
- GRB 241114B: cubesat Avion detection
- GRB 241209A: VLT optical observations
- GRB 241209A: GOTO optical upper limits
- GRB 241209B: SVOM/ECLAIRs and GRM detection of a long burst
- GRB 241209A: Swift detection of a short burst
- GRB 241206A: DDOTI Upper Limit on the Afterglow
- AT2024adec: X-ray Upper Limits from EP-FXT Observation
- EP241206a: BOOTES Global Network optical limits
- GRB 241207C: MAXI/GSC detection
- GRB 241206B: SVOM/MXT observations: a probable flare from the QSO 1ES 1959+650
- EP241113a: Keck/LRIS spectroscopic observation and tentative redshift
- GRB 241206A: Fermi GBM Final Real-time Localization