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.
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').
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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.
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subject:"Swift"body:"GRB"submitter:"Judith Racusin"- GRB 091102: GROND Upper Limits
- GRB 091102: BOOTES-3 observations
- 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 091031: Fermi GBM detection
- GRB 091024: Fermi LAT upper limits
- GRB 090926a, SMARTS optical/IR afterglow observations
- GRB 091018: Skynet/PROMPT Observations of Possible Host Galaxy
- GRB 091029, SMARTS optical/IR afterglow observations
- GRB 091018, SMARTS optical/IR afterglow observations
- GRB 090920: Skynet/DSO Detection
- GRB091029: Swift/UVOT observations
- GRB 091029: Skynet/PROMPT Continued Observations of Fading
- GRB 091029: Swift XRT refined analysis
- Fermi Gamma-ray Burst Monitor trigger 091028818 is not a GRB
- GRB 091029: BOOTES-3 observations
- GRB 091029: Swift-BAT refined analysis
- GRB 091029: Enhanced Swift-XRT position
- GRB091024 optical observations
- GRB 091029: Gemini-South Redshift
- 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 091024: Keck/LRIS Spectroscopy
- GRB 091024: YNAO-GMG observations
- 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
- GRB 091020 : Xinglong TNT upper limit
- 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: Super-LOTIS early observations
- GRB091024: VRcIc 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: Xinglong TNT optical observation
- GRB 091024 : Faulkes Telescope North - Afterglow Confirmation
- GRB 091024 Gemini-North redshift
- GRB 091024: GRAS004 optical observations
- GRB 091024: Faulkes Telescope North Afterglow Candidate
- GRB 091024: Swift detection of a burst
- GRB 091018: Skynet/PROMPT Continued Observations of Fading
- GRB 091020: Additional Lick observations
- Konus-Wind observations of GRB 091020 (correction to GCN 10057)
- GRB 091020: Lick observations
- Konus-Wind observations of GRB 091010
- GRB 091020: Swift-XRT refined analysis
- GRB 091018: Swift XRT refined analysis
- GRB091020 Swift/UVOT observations
- GRB 091020: NOT spectroscopic redshift
- GRB 091020: MASTER optical transient polarimetry
- 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: miniTAO/ANIR Observations
- GRB 091018: Skynet/PROMPT Observations of Fading
- Konus-RF observation of GRB 091018
- GRB 091018 : Faulkes Telescope South Observations
- GRB 091018: BOOTES-3 observations
- GRB 091018: VLT/X-shooter spectra
- GRB091018: Swift/UVOT observations
- GRB 091018: Swift-BAT refined analysis
- GRB 091018: GROND observations
- GRB091018: Magellan Echellette Observations
- GRB 091018: Enhanced Swift-XRT position
- GRB 091018: ROTSE-III Detection of Optical Counterpart
- GRB 091015: Skynet/PROMPT Observations
- GRB 091018: Swift detection of a burst with optical afterglow
- Fwd: GRB 091003: Possible Supernova Component Retraction
- GRB 091003: Possible Supernova Component
- GRB 091003: Gemini-N redshift of possible host galaxy
- GRB 091010: optical obsevation
- GRB 091015: RTT150 optical observations
- GRB 090726 R band observations
- GRB 091010: optical afterglow candidate rejection
- GRB 091015: correction to GCN 10025
- GRB 090815: a faint long GRB localized by INTEGRAL
- GRB 091010: Swift-XRT refined analysis