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"26124 results found.
- GRB 240523A: Enhanced Swift-XRT position
- GRB 240523A: Swift detection of a burst
- GRB 240521B: Fermi GBM Observation
- GRB 240513A: Swift-XRT afterglow detection
- GRB 240521B: Swift/BAT-GUANO arcminute localization of a long burst
- LIGO/Virgo/KAGRA S240515m: Upper limits from Swift/BAT-GUANO
- LIGO/Virgo/KAGRA S240514x: Upper limits from Swift/BAT-GUANO
- LIGO/Virgo/KAGRA S240513ei: Upper limits from Swift/BAT-GUANO
- GRB 240504A: VZLUSAT-2 detection
- GRB 240516A: Swift/UVOT Upper Limits
- GRB 240516A: Swift-BAT refined analysis
- GRB 240516A ATCA radio observations
- IPN triangulation of GRB 240514B (short)
- GRB 240513A: Swift ToO observations
- GRB 240516A: AstroSat CZTI detection
- GRB 240516A: Swift-XRT refined Analysis
- GRB 240514E: A possible candidate BD-21 1074
- GRB 240516A: Fermi GBM Observation
- GRB 240511A: Observations from GTC/OSIRIS+
- GRB 240502C: Zeiss-1000 at Koshka observations of GOTO24bao optical counterpart candidate
- GRB 240516A: GOTO optical upper limit
- GRB 240516A: Swift detection of a burst
- Swift GRB240516.15: Global MASTER-Net observations report
- GRB 240511A: radio detection of afterglow candidate
- GRB 240514E: MAXI/GSC detection of a probable afterglow
- GRB 240513A: Swift-XRT observations
- LIGO/Virgo/KAGRA S240507p: Upper limits from Swift/BAT-GUANO
- LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
- LIGO/Virgo/KAGRA S240505av: Upper limits from Swift/BAT-GUANO
- GRB 240513A: Tiled Swift observations
- GRB 240513A: Fermi-LAT detection
- GRB 240511A: Fermi GBM Observation
- GRB 240511A: Swift-BAT refined analysis
- GRB 240511A: J-band observations with WINTER
- GRB 240511A: Enhanced Swift-XRT position
- GRB 240511A : MITSuME Akeno optical upper limits
- GRB 240511A: Swift-XRT refined Analysis
- GRB 240511A: optical afterglow detection from the NOT
- Swift GRB 240511A: Global MASTER-Net observations report
- GRB 240511A: Prompt enhanced Swift-XRT position
- GRB 240511A: Swift detection of a burst
- GRB 240504A: Fermi GBM Observation
- IPN triangulation of GRB 240504A
- GRB 240502A: 1.3m DFOT Optical upper limit
- GRB 240504A: Swift/BAT-GUANO detection of a burst outside the coded FOV
- GRB 240415A 1.3m DFOT Optical upper limit
- GRB 240502C: GOTO possible optical counterpart candidates
- X-ray transient EP240414a: Detection of associated supernova
- LIGO/Virgo S240422ed: Swift XRT observation of EP240426a
- GRB 240414A: NOEMA detection
- LVK S240422ed: Further Swift-XRT followup of three sources
- LIGO/Virgo/KAGRA S240422ed: Magellan Follow-up Observations of Swift/XRT candidates
- LIGO/Virgo/KAGRA S240422ed: 2.5m PRL Telescope follow-up of the Swift/XRT source S240422ed_X190
- LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-FXT for the Potential Electromagnetic Counterparts Reported by Swift and DECam
- LIGO/Virgo/KAGRA S240422ed: SRG/eROSITA archival upper limits for Swift/XRT candidates
- GRB 240419B: Swift-BAT refined analysis
- GRB 240421B: Swift-BAT refined analysis
- LIGO/Virgo/KAGRA S240422ed: Himalayan Chandra Telescope follow-up of the Swift/XRT source S240422ed_X101
- IceCube-240424A - IceCube observation of a high-energy neutrino candidate track-like event
- LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-WXT for the Potential Electromagnetic Counterparts Reported by Swift and DECam
- LIGO/Virgo S240422ed: Swift-XRT detection of 3 possible counterparts
- LIGO/Virgo/KAGRA S240422ed: NOT J-band upper limit on the Swift/XRT source S240422ed_X61
- LIGO/Virgo/KAGRA S240422ed: X-ray Upper Limits from EP-WXT for the Three Potential Electromagnetic Counterparts Reported So Far
- GRB 240421B: GRBAlpha detection
- LIGO/Virgo/KAGRA S240422ed: WINTER J-band upper limits on the Swift/XRT source S240422ed_X61
- LIGO/Virgo/KAGRA S240422ed: GW-MMADS DECam upper limits on the Swift/XRT source S240422ed_X61
- GRB 240419A: Swift-BAT refined analysis
- GRB 240418A: Swift-BAT refined analysis
- LXT240402A/GRB240402B: Chandra X-ray detection
- GRB 240419A: Possible ATCA radio detection
- GRB 240421B: ATCA radio observations
- LIGO/Virgo/KAGRA S240421ar: Upper limits from Swift/BAT-GUANO
- GRB 240414A: AMI-LA radio observations
- GRB 240419B : MITSuME Akeno optical upper limits
- GRB 240415B: Swift-XRT observations
- GRB 240415A: Swift-XRT refined Analysis
- GRB 240421B: AstroSat CZTI detection
- GRB240421B: Zadko Observations
- Swift GRB 240421B: Global MASTER-Net observations report
- GRB 240421B: Fermi GBM Observation
- GRB 240421B: Swift-XRT refined Analysis
- GRB240421B: BOOTES-5/JGT optical upper limit
- GRB 240421B: Swift/UVOT Upper Limits
- GRB 240421B: Enhanced Swift-XRT position
- GRB 240421B: Swift detection of a burst
- GRB240419A: Skynet Optical Afterglow Analysis
- GRB240418A - Candidate afterglow from NIRES
- GRB 240419B: Swift/UVOT Upper Limits
- GRB 240419A: Swift/UVOT Upper Limits
- GRB 240419B: Swift-XRT refined Analysis
- GRB 240419B: optical afterglow from the NOT
- Swift GRB 240419B: Global MASTER-Net observations report
- GRB 240419B: Enhanced Swift-XRT position
- Swift GRB 240419A: Global MASTER-Net observations report
- GRB 240418A: Swift/UVOT Upper Limits
- GRB 240419A: REM NIR afterglow detection
- GRB 240419A: Swift-XRT refined Analysis
- GRB 240418A: Swift-XRT refined Analysis
- GRB 240419B: Swift detection of a burst
- GRB 240411B: Swift/UVOT Detection