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"12312 results found.
- GRB 060223a: Swift/UVOT refined analysis
- GRB 060223: Swift/UVOT Confirmation of Optical Afterglow
- GRB 060219: Swift/UVOT Upper Limits
- GRB 051221B: Swift-XRT Team Refined Analysis
- GRB 060219: Swift-BAT detection of a weak burst
- GRB 060211B: Swift/UVOT Upper Limits
- Swift UVOT observations of GRB060213
- GRB060213: MASTER final result
- GRB 060211b: WIRO NIR Observations
- GRB060213:_MASTER_optical_observation
- GRB 060211a: WIRO NIR Observations
- GRB060211B: REM optical and NIR observations
- GRB060210: Swift/UVOT Upper Limits
- GRB 060211B: Swift-BAT detection of a burst
- GRB 060211: Swift detection of a long burst
- GRB 060210: Swift detection of a burst
- GRB 060206: Swift/UVOT Observations
- GRB060209A: MASTER optical observation
- GRB 060209(?): Swift-BAT detection of a possible burst
- GRB 060203: Swift/UVOT upper limits
- GRB060204a: Swift XRT Source is not GRB Afterglow
- GRB 060206: Lick 3m Spectroscopy
- GRB060204a: Swift XRT Detection of an Afterglow Candidate
- GRB 060204A: Swift XRT upper limit
- GRB060204B: Swift/UVOT refined analysis
- Swift XRT Observation of GRB 060204C
- GRB060204B, optical observation
- GRB 060204B: Swift detection of a burst
- GRB060203 - Swift UVOT observation
- GRB 060202: GETS observation
- GRB 060202: Swift/UVOT upper limits
- GRB 060202: Swift detection of a burst
- GRB060130: Further R-band imaging
- GRB 060130: Swift/XRT observation
- GRB060124: optical observation
- GRB 060116 HST observations
- GRB 060123: Swift detection of a very long, faint burst
- GRB060124:MASTER optical observation
- GRB 060121: Swift/UVOT upper limits
- GRB060108: photometric redshift determination
- GRB 060116: Swift/UVOT upper limits
- GRB060115: REM observations
- GRB 060116: Swift-BAT detection of a burst
- GRB 060115: Swift/UVOT upper limits
- GRB 060114: REM observations
- GRB 060114: Swift/UVOT Observations
- GRB 060114: Swift XRT upper limit
- GRB 060111A: refined UVOT anaysis
- GRB060111A: RTT150 optical observations
- GRB 060111: Swift detection of a burst
- GRB 060108: z-band imaging from Gemini-North
- GRB 060110: Super-LOTIS observations
- GRB 060109: Swift/UVOT upper limits
- GRB 060108: ISAS early observations and near IR upper limit
- Swift UVOT correction to GCN 4455
- GRB 060109: Swift Detection of a long burst
- GRB 060108: Mitsume optical observations
- GRB 060108: Swift/UVOT upper limits
- GRB060108: Swift detection of its 100th GRB
- GRB 060105: MDM Observation
- GRB 060105: ISAS observations and near IR upper limit
- GRB 060105: Swift/UVOT upper limits
- GRB 060105: Mitsume optical observations
- GRB 060102 - no XRT afterglow
- GRB060105: Swift detection of a bright long burst
- GRB051211B: optical observations
- GRB 051227: optical observation
- GRB 051227: Swift/UVOT Upper Limits (Possible U-band
- GRB051117B: optical observation
- GRB 051221A: MDM Optical Observations
- GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
- GRB 051221B: TAROT optical limits
- GRB 051221A: RAPTOR Fading Counterpart Constraint
- GRB 051221B: BOOTES optical observations.
- Swift-BAT detection of a possible burst
- GRB 051221: Swift/UVOT upper limits
- GRB 051221: Swift detection of a bright short burst
- GRB051211A: possible optical candidate
- GRB 051211A: Swift/UVOT upper limits
- GRB 051211B: Swift/UVOT upper limits - correction
- GRB 051211B: Swift/UVOT upper limits
- GRB 051211A and GRB051211B: BOOTES simultaneous observations
- GRB 051210: Swift/UVOT upper limits
- GRB 051211: Swift XRT upper limit
- GRB051117B: optical observation
- GRB051117B: Swift XRT refined analysis
- GRB051117b: No Swift/UVOT Detection
- GRB 051109B: GAO 150cm telescope Optical limit
- GRB 051109B : Nainital upper limits
- GRB050925: analysis of the XMM-Newton observation
- GRB 051109A Milagro GeV/TeV Observations
- GRB/SGR 050925: XMM-Newton ToO observation
- GRB051111: Swift/UVOT Observations
- GRB 051103 Milagro GeV/TeV Observations
- GRB 051105a: GETS optical limit
- GRB 051109b: GETS observation
- GRB051109B: no UVOT source detected
- GRB051105B: REM Optical observation
- GRB051105B: Swift/XRT upper limit
- GRB051105B: Swift/UVOT upper limit