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"19538 results found.
- 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
- GRB 091112: Swift-BAT refined analysis
- GRB 091112: Fermi GBM observation
- 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: Enhanced Swift-XRT position
- GRB 091109B: ROTSE-III Optical Limits
- GRB 091109B: Swift detection of a short burst
- GRB 091109: Swift-XRT refined analysis
- GRB 091109: Swift/UVOT observations
- GRB 091109: Swift-BAT refined analysis
- GRB 091109: Enhanced Swift-XRT position
- GRB 091109: Swift detection of a burst with optical afterglow
- GRB 091029: Observations from Stardome Observatory
- GRB 091104: Swift-BAT refined analysis
- GRB 091104: Swift XRT Refined Analysis
- GRB 091104: Swift/UVOT Upper Limits
- GRB091026 : IRSF NIR upper limit
- GRB091102 : MOA optical upper limit
- GRB 091104: Enhanced Swift-XRT position
- GRB 091104: Swift detection of a burst
- GRB 091102 : Faulkes Telescope South Upper Limits
- GRB 091102A: Fermi GBM observation
- GRB 091102: Swift-XRT refined analysis
- GRB 091102: Swift/UVOT Upper Limits
- GRB 091102: GROND Upper Limits
- GRB 091102: Swift-BAT refined analysis
- GRB 091102: Swift/XRT localization
- GRB 091102: ROTSE-III Optical Limits
- GRB 091102: Swift/UVOT Finding Chart Observation
- GRB 091102: Swift detection of a burst
- GRB 091024: optical observations
- GRB 091024: Fermi LAT upper limits
- GRB 090920: Skynet/DSO Detection
- GRB091029: Swift/UVOT observations
- GRB 091029: Swift XRT refined analysis
- GRB 091029: Swift-BAT refined analysis
- GRB 091029: Enhanced Swift-XRT position
- GRB 091029: Skynet/PROMPT Observations of Peak and Fading
- GRB 091029: GROND Detection of the Optical/NIR Afterglow
- GRB 091029: Swift detection of a burst with an optical counterpart
- A mistake in testing a new function in Swift
- GRB 091020: Fermi GBM observation
- GRB 091026: Suzaku WAM observation of the prompt emission
- GRB 091026: GROND Upper Limits
- GRB 091020: Late TLS detection
- GRB 091026: Swift-BAT refined analysis
- Radio afterglow detection from GRB 091020
- GRB 091026: Swift/UVOT Upper Limits
- GRB 091024: Burst was outside the Swift-BAT FOV after T0(BAT)+460sec
- GRB 091026: Swift-XRT refined analysis
- GRB 091026: Enhanced Swift-XRT position
- Konus-Wind and Konus-RF observations of GRB 091024
- GRB 091026: Updated Swift-XRT position
- GRB 091026: Swift detection of a Gamma Ray Burst
- Swift-BAT Triggers 373776-373778 are not real
- GRB091024 Swift/UVOT Upper Limits
- GRB 091024: TLS Upper Limit
- GRB 091020: Early TLS Multicolor detections, red afterglow
- GRB 091024: KAIT optical afterglow observations
- GRB 091024: Swift-BAT refined analysis
- Swift-BAT Triggers 373679-373684 are not real
- GRB 091024: Fermi GBM Observations
- GRB 091024: Swift-XRT team refined analysis
- Swift-BAT trigger 373691 is a galactic bulge transient
- GRB 091024 : Faulkes Telescope North - Afterglow Confirmation
- GRB 091024: Faulkes Telescope North Afterglow Candidate
- GRB 091024: Swift detection of a burst
- GRB 091020: Swift-XRT refined analysis
- GRB 091018: Swift XRT refined analysis
- GRB091020 Swift/UVOT observations
- GRB 091020, Swift-BAT refined analysis
- GRB 091020: Enhanced Swift-XRT position
- GRB 090926A: Late-time Gemini South Observations and Possible Jet Break
- GRB 091020: Swift detection of a burst with an optical afterglow
- GRB 091018: Skynet/PROMPT Observations of Fading
- Konus-RF observation of GRB 091018
- GRB 091018 : Faulkes Telescope South Observations
- GRB091018: Swift/UVOT observations
- GRB 091018: Swift-BAT refined analysis
- GRB 091018: Enhanced Swift-XRT position
- GRB 091018: ROTSE-III Detection of Optical Counterpart
- GRB 091018: Swift detection of a burst with optical afterglow
- GRB 090726 R band observations
- GRB 091010: Swift-XRT refined analysis
- Radio observation of GRB090927 with ATCA
- GRB 091010: Fermi GBM observation
- GRB 090531A: Skynet/PROMPT Observations
- GRB 090530A: Skynet/DSO Detections
- GRB 091010: Enhanced XRT position
- GRB 091010: GROND afterglow candidate
- GRB 091010: Swift/UVOT Upper Limits
- GRB 091010: Swift-XRT position
- GRB 090518: Skynet/PROMPT Observations