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.
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"26207 results found.
- GRB 111029A: ROTSE-III Optical Limits
- GRB 111029A: Swift detection of a burst
- GRB 111026A: Swift detection of a burst
- GRB111022B: D50 optical limit
- GRB 111022B: BTA Optical Observations
- GRB 111022B: Swift/UVOT upper limits
- GRB 111022A: Swift/UVOT Upper Limits
- GRB 111022B, Swift-BAT refined analysis
- GRB 111022B: Swift-XRT refined Analysis
- GRB 111022A: Swift-XRT refined Analysis
- GRB 111022B: MITSuME Akeno Optical upper limits
- GRB 111022A: Swift-BAT refined analysis
- GRB 111022A: Preliminary UVOT TDRSS Non-Detection
- GRB 111022B: Swift detection of a burst
- GRB 111022A: Swift detection of a burst
- GRB 111020A: Swift-XRT refined Analysis
- GRB 111020A: Swift/UVOT Upper Limits
- GRB 111020A: Faulkes Telescope South observations
- GRB 111020A: Swift-BAT refined analysis
- GRB 111020A: Swift detection of a short burst
- GRB 111018A: Swift/UVOT Upper Limits
- GRB 111018A: Swift-BAT refined analysis
- GRB 111018A: Swift-XRT refined Analysis
- GRB 111018A: GROND Upper Limits
- GRB 111018A: Swift detection of a burst
- GRB 111017A: Fermi GBM Detection
- GRB111016A: D50 optical limit
- GRB 111016A: Gemini Detection of the NIR Counterpart
- GRB 111016A: Swift/UVOT Detection of a Source
- GRB 111016A: Swift-BAT refined analysis
- GRB 111016A: P60 Afterglow Candidate
- GRB 111016A: MITSuME Akeno Optical upper limits
- GRB 111016A: Swift-XRT refined Analysis
- GRB 111016A: Swift-XRT observations
- GRB 111016A: Swift detection of a burst
- GRB 111008A: Swift/UVOT Upper Limits
- Konus-Wind observation of GRB 111008A
- GRB 111008A: IAC80 I-band observations
- GRB 111008A: Swift-XRT refined Analysis
- GRB 111008A, GROND observations
- GRB 111008A: Gemini optical counterpart
- GRB 111008A, Swift-BAT refined analysis,
- GRB 111008A: Swift detection of a burst
- GRB 111005A: GROND NIR observations
- GRB 111005A: Swift-BAT refined analysis
- GRB 111005A: Swift detection of a burst
- GRB 111003A: Fermi GBM detection
- GRB 110921A: MITSuME-Akeno Optical photometry
- Skynet/Dolomiti observations of GRB 110928A
- Skynet observations of GRB 110928A
- GRB 110928A: RAPTOR Limits During Gamma-ray Emitting Interval
- GRB 110928A: Swift/UVOT Upper Limits
- Trigger 504307: Swift detection of MAXI J1836-194
- GRB 110928A: Swift-XRT refined Analysis
- GRB 110825A: GROND Observations
- GRB 110928A: P60 Observations
- GRB 110928A: Further PAIRITEL NIR Observations
- GRB 110928A: Swift-BAT refined analysis
- GRB 110928A: Swift-XRT observations
- GRB 110928A: Swift/UVOT finding chart observation
- GRB 110928A: ROTSE-III Optical Limits
- GRB 110928A: Swift detection of a burst
- Fermi GBM triggers 110923481, 110924391 and 110925200 are not GRBs
- Swift-BAT trigger 503926 is noise
- GRB 110924A: Swift detection of a possible burst
- GCN for GRB 110921B
- GRB 110921A: Swift/UVOT Observations
- GRB 110921A: Fermi GBM observation
- GRB 110921A: Swift-XRT refined Analysis
- GRB 110921A, Swift-BAT refined analysis
- GRB 110918A: Liverpool Telescope optical observations
- GRB 110921A: MITSuME Akeno Optical Observation
- GRB 110918A: Swift-XRT refined Analysis
- GRB 110921A: Swift detection of a burst
- GRB 110915B : X-ray afterglow confirmation
- GRB 110918A: Swift/UVOT Detection of the Optical Counterpart
- GRB 110918A: Afterglow Confirmation from PTF
- GRB 110918A: GROND detection of the afterglow candidate
- GRB 110918A: Swift-XRT observations
- Swift detection of short bursts from PSR J1647-4552
- GRB 110915A: Konus-Wind and Swift/BAT joint spectral analysis
- GRB 110915B: GROND Observations of the Optical/NIR Afterglow Candidate
- GRB 110915A: Swift/UVOT Upper Limits
- GRB 110915B: Swift/UVOT Upper Limits
- GRB 110915A: GROND Upper limits
- GRB 110915A, Swift-BAT refined analysis
- GRB 110915A: Swift-XRT refined Analysis
- GRB 110915B: XRT afterglow candidate
- GRB 110903A: Suzaku WAM observation of the prompt emission
- GRB110915A MITSuME Okayama J-band upper-limit
- GRB 110915A: MITSuME Akeno Optical upper limits
- GRB 110915A: Swift detection of a burst
- GRB 110906A(?): Burst detection (unconfirmed) from Swift-BAT slew data
- MAXI J1836-194 (originally GRB 110905A): Swift-BAT refined analysis
- GRB 110905A: Potential BAT trigger on MAXI J1836-194
- GRB 110905A: KAIT observations
- GRB 110905A: Swift detection of a burst
- GRB 110903A: Fermi GBM observation
- GRB 110903A: Swift/UVOT Upper Limits
- GRB 110903A: Swift-XRT observations