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"
18431 results found.
- GRB 100713A: Swift XRT refined analysis
- GRB 100713A : IRSF/SIRIUS NIR upper limits
- GRB100713A: Swift/UVOT observations
- GRB 100713A: GROND upper limits
- GRB 100713A: optical upper limit
- GRB 100713A: TELMA and 1.5m OSN optical observations
- GRB100713A: Swift X-ray afterglow detection
- GRB 100628A: Chandra observations
- GRB 100628A: Swift XRT/UVOT refined analysis
- Tentative redshift of GRB100704A from Swift-XRT data
- Konus-Wind observation of GRB 100704A
- GRB 100704A: Swift XRT refined analysis
- GRB 100704: Swift/UVOT Upper Limits
- GRB 100704A: Fermi GBM observation
- GRB 100704A: Swift-BAT refined analysis
- GRB100704A: MOA optical upper limit
- GRB 100704A: Enhanced Swift-XRT position
- GRB 100704A: Swift detection of a burst
- GRB 100702A, Swift-BAT refined analysis
- GRB 100702A: Swift XRT refined analysis
- Swift/UVOT observations of GRB100702A - correction
- Swift/UVOT observations of GRB100702A
- GRB 100702: ROTSE-III Optical Limits
- GRB 100702A: Swift detection of a short burst
- GRB 100615A: Chandra X-ray ToO Observation
- GRB 100213B: Detection of Fading Optical Afterglow
- GRB 100625A: Fermi GBM detection
- GRB 100628A: Swift XRT refined position
- GRB100625A: GROND confirmation of constant source
- GRB100628A : MOA optical upper limit
- GRB 100628A: Swift/UVOT Upper Limits
- GRB 100628A: Swift XRT detection of a possible X-ray afterglow
- GRB 100628A: INTEGRAL SPI-ACS light curve
- GRB 100628A: Swift-BAT refined analysis
- GRB 100628A: Swift detection of a short hard burst
- Swift-BAT trigger 426048 is not a burst
- GRB 100614A: CrAO optical limit
- GRB 100625A: Swift/UVOT Upper Limits
- GRB 100625A: Swift-BAT refined analysis
- Konus-Wind observation of GRB 100625A
- GRB 100625A : IRSF/SIRIUS NIR upper limit
- GRB 100625A: Swift-XRT Team refined analysis
- GRB 100625A: Enhanced Swift-XRT position
- GRB100625A : MOA optical upper limit
- GRB 100625A: Swift detection of a short hard burst
- GRB 100418A: late time optical observations
- Konus-Wind observation of GRB 100621A
- GRB 100621A: IRSF/SIRIUS NIR Observation
- GRB 100621A MOA-II optical limit
- GRB 100621A: Swift/UVOT observations
- GRB 100621A: Swift XRT refined analysis
- GRB 100621A: Swift-BAT refined analysis
- GRB 100621A: GROND observation of bright NIR afterglow
- GRB 100621A: Enhanced Swift-XRT position
- GRB 100621A: Prompt enhanced Swift-XRT position
- GRB 100621A: ROTSE-III Optical Limits
- GRB 100621A: Swift detection of a burst
- GRB 100606A: Optical Limits
- GRB 100619A: Fermi GBM detection
- GRB 100619A: Swift/UVOT Upper Limits
- GRB 100619A: Swift-XRT refind analysis
- GRB 100619A: Enhanced Swift-XRT position
- GRB 100619A: Swift-BAT refined analysis
- GRB 100619A: Swift detection of a burst
- GRB 100615A: Swift/UVOT Upper Limits
- GRB 100614A: Swift/UVOT Upper Limits
- GRB 100614A: MASTER-Net optical alert observations
- GRB 100614A: Swift-BAT refined analysis
- GRB 100615A: Fermi GBM detection
- GRB 100615A: Swift-BAT refined analysis
- GRB 100614A: Enhanced Swift-XRT position
- GRB 100615A: Enhanced Swift-XRT position
- GRB 100615A: Swift-XRT refined analysis
- GRB 100614A: Swift-XRT refined analysis
- GRB 100615A: PAIRITEL NIR Upper Limits
- GRB 100615A: Swift detection of a burst
- GRB 100614A: Liverpool Telescope Observations
- GRB 100614A: Swift detection of a burst
- GRB 100606A: Suzaku WAM observation of the prompt emission
- Trigger 424161: Swift/BAT trigger on XTE J1946+274/GRO J1944+26
- Konus-Wind observation of GRB 100606A
- Radio detection of GRB100418a with ATCA
- GRB 100606A: Swift/UVOT Upper Limits
- GRB 100606A Swift-XRT refined analysis
- GRB 100606A: Swift-BAT refined analysis
- GRB 100606A: Enhanced Swift-XRT position
- Swift Trigger 424040 is not a GRB
- GRB 100606A: Prompt enhanced Swift-XRT position
- GRB 100606A: Swift detection of a burst
- Swift detection of outburst from the SFXT IGR J18410-0535
- GRB 100111A: Maidanak optical observations
- GRB 100418A: Maidanak optical observations
- GRB 100513A: CrAO optical observations
- GRB 100514A: CrAO optical observations
- GRB 100526A: optical upper limit
- Swift UVOT and UVOT-enhanced XRT position for GRB 100528A
- GRB100526B: GROND Upper limits
- GRB 100526B: Swift-XRT confirmation of fading afterglow
- GRB 100526B: Swift/UVOT Upper Limits
- GRB 100526A: Swift/UVOT Upper Limits