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"26228 results found.
- GRB 091221: Skynet/PROMPT Detections
- GRB 091221: Fermi GBM Observation
- GRB 091117: Swift-XRT late time observations
- GRB 091221 Swift-BAT refined analysis
- GRB 091221: Swift/UVOT refined analysis
- GRB 091221: Swift-XRT refined analysis
- GRB 091221: ROTSE-III Detection of Optical Counterpart
- GRB 091221: Swift detection of a burst
- Swift trigger 379449 (possible GRB) is not a burst
- GRB 091215: Faulkes Telescope North observations
- Trigger 379449: Swift detection of a possible burst
- GRB 091208A: Suzaku WAM observation of the prompt emission
- GRB 091208A: GAO 150cm telescope Optical Observation
- Konus-Wind observation of GRB 091208A
- GRB 091208B: GAO 150cm telescope Optical Observation
- GRB091208A: Swift/UVOT refined analysis
- GRB 091208B: GROND observations
- GRB 091208A: Swift-XRT observations
- GRB091208B: NOT optical observations
- GRB 091208B: Swift-XRT refined analysis
- GRB091208B: Swift/UVOT refined analysis
- GRB 091208B: Fermi GBM observation
- GRB 091208B, Swift-BAT refined analysis
- GRB 091208A Swift-BAT refined analysis
- GRB 091208B: Faulkes Telescope North and South Optical Afterglow
- GRB 091208A, RIMOTS optical upper limits
- GRB 091208B: MITSuME Akeno Optical Observation
- GRB 091208B: MITSuME Okayama Optical Observation
- GRB 091208B, RIMOTS optical upper limits
- GRB 091208B: Swift detection of a burst with an optical afterglow
- GRB 091208B: BOOTES-3 optical afterglow
- GRB 091208: ROTSE-III Optical Limits
- GRB 091208: Swift detection of a burst
- GRB 091123: Suzaku WAM observation of the prompt emission
- GRB 091127: Skynet/PROMPT Observations of Possible Host Galaxy
- GRB 091127: GAO 150cm telescope Optical Observation
- GRB 091109A: GROND confirmation of redshift z = 3.5
- GRB091127: Continuing Swift/UVOT Observations
- GRB091202: Swift-XRT refined analysis
- GRB 091202: Swift/UVOT Upper Limits
- GRB 091202: Liverpool Telescope observations
- GRB 091127: Zadko Telescope Observations
- GRB 091126A: Suzaku WAM observation of the prompt emission
- GRB 091202: TAROT Calern observatory optical observations
- GRB 091202: Liverpool Telescope Observations
- GRB 091117: Chandra Observations
- GRB 091127: Skynet/PROMPT Continued Observations of Fading
- GRB 091123: Fermi GBM detection of a very long burst
- GRB 091126B: Fermi GBM detection
- GRB 091127: Suzaku WAM observation of the prompt emission
- GRB 091126: Fermi GBM detection
- GRB 091130B: Swift-XRT team refined analysis
- GRB 091130B: Swift-BAT refined analysis
- GRB 091130B: Swift/UVOT Upper Limits
- GRB 091127: Skynet/PROMPT Observations of Fading
- Swift trigger 377436 (possible GRB 091130A) is not a burst
- GRB 091130B: Swift detection of a burst
- GRB 091130: Swift detection of a possible burst
- GRB 091128: Fermi GBM detection
- Konus-Wind observation of GRB 091127
- GRB 091127: TAROT La Silla observatory optical observations
- GRB 091127: Further NOT optical observations
- GRB 091127: Fermi GBM detection
- GRB 091127: Swift-XRT afterglow detection and analysis
- GRB 091127: TAROT La Silla observatory optical decay
- GRB 091127: Swift/UVOT observations
- GRB 091127: Swift-BAT refined analysis
- GRB 091127 : GROND observations
- GRB 091127: Swift/UVOT Detection of an Optical Afterglow
- GRB 091127: Liverpool Telescope afterglow candidate
- GRB 091127: Swift detection of a burst
- GRB 091120: MAXI GSC detection
- GRB 091120: Fermi GBM observation
- GRB 091117A: Suzaku WAM observation of the prompt emission
- GRB 091117A: Swift/UVOT followup observations
- GRB 091117: Swift-XRT observations
- GRB 091117 BAT refined analysis
- GRB091117: Gemini South Observations
- GRB 091117: Swift XRT refined analysis
- GRB 091117A Detected in ground analysis of BAT data and IPN triangulation
- GRB 091112: Suzaku WAM observation of the prompt emission
- GRB 091102A: Suzaku WAM observation of the prompt emission
- GRB 091109B: Suzaku WAM observation of the prompt emission
- GRB091111: Swift XRT refined analysis
- Konus-Wind and Konus-RF observations of GRB 091031
- GRB 091112: Swift-BAT refined analysis
- GRB 091112: Fermi GBM observation
- GRB 091031: Fermi LAT detection of a faint burst
- GRB 091112: Swift detection of a possible burst
- GRB 091109B: Swift/UVOT Upper Limits
- GRB 091109B: Swift-XRT Team refined analysis
- GRB 091109B: Swift-BAT refined analysis
- GRB 091109B: ROTSE-III Optical Limits
- GRB 091109B: Swift detection of a short burst
- GRB 091030: Fermi GBM detection
- GRB 091109: Swift-XRT refined analysis
- GRB 091109: Swift/UVOT observations
- GRB 091109: Swift-BAT refined analysis
- GRB 091109: Swift detection of a burst with optical afterglow
- GRB 091029: Observations from Stardome Observatory