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"
6094 results found.
- GRB 060121: Swift/UVOT upper limits
- GRB 060121: Swift XRT refined analysis
- GRB 060121: Swift XRT refined position
- GRB060121: SARA Observations
- GRB 060121: Infrared Observations
- GRB 060116: possible I-J dropout
- GRB 060117: Refined analysis of the Swift-BAT burst
- GRB 060110: XRT position and analysis
- GRB 060115: Refined analysis of the Swift-BAT burst
- GRB 060114: Swift XRT upper limit
- GRB 060108: further analysis of VLT images
- GRB 060111B: Swift XRT refined analysis
- GRB060111 : XRT refined analysis
- GRB 060110: IR Candidate Afterglow
- GRB 060108: ISAS early observations and near IR upper limit
- GRB060108: P200 Ks Observations
- GRB 060105: ISAS observations and near IR upper limit
- GRB 060105: BAT refined analysis
- Swift-BAT trigger 175653 is not an astrophysical source
- GRB051227: SARA Observations
- GRB 051221B: Optical Observations with Kuiper 1.54m
- GRB 051227: Swift/UVOT Upper Limits (Possible U-band
- GRB051016: analysis of the XMM-Newton observation
- GRB 051221A: Chandra Afterglow Position
- GRB 051221B: Refined analysis of the Swift-BAT burst
- GRB 051221: Swift XRT refined analysis
- Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
- GRB051211A (=H3979): Refined Analysis
- GRB 051215: near-infrared observations
- GRB 051213: Swift-BAT refined analysis
- GRB 051211B: Swift XRT confirmation of the afterglow
- GRB 051211B: Swift XRT Observations
- GRB 051210: Swift XRT refined analysis
- GRB 051117b: NIR observations
- GRB051117A : XRT refined analysis
- GRB 051117B: Lulin R and I band observation
- GRB051114: results of the Swift-XRT observation
- GRB051111: XRT preliminary analysis
- GRB 051111: Swift-BAT refined analysis
- GRB 051111a: IR photometry
- GRB 051109B: Swift-BAT refined analysis
- GRB051109B: XRT refined analysis
- GRB051109A: XRT refined analysis
- GRB 051109a: IR Photometry and Astrometry
- GRB 051109a: IR Detections
- GRB051028: Swift-XRT refined analysis
- XRT observations of GRB 051105A
- GRB 051021, Optical Observations
- Chandra Observations of GRB 051022
- GRB051012: Swift-XRT analysis
- GRB 051022 Chandra Observations scheduled
- GRB 051022: SOAR JKs Observations
- GRB051021b: Magellan IR Imaging
- GRB 051022, J & K-band observation
- GRB 051021: P200 Ks Observations
- GRB051021: Swift XRT analysis
- GRB 051016b: Gemini Near IR Observations
- GRB 051016: Swift-BAT refined analysis
- GRB051008: Swift XRT refined analysis
- GRB051008: Refined analysis of the Swift-BAT burst
- GRB 051006: optical observations at Sierra Nevada
- GRB 051001, optical observations at Mt. John
- GRB 051001: AAT infra-red observations
- GRB 051001: Swift-BAT refined analysis
- GRB050925: Swift/XRT limits
- GRB/SGR 050925: IR Observations
- Refined analysis of the Swift-BAT soft short burst
- GRB 050922B: Correction to BAT refined analysis, longer burst
- GRB050922C: TNG spectroscopic observations
- GRB050922B: refined XRT analysis
- GRB050922C: Optical Observations
- GRB 050922C: NOT optical observations
- GRB050820B: analysis of the XMM-Newton observation
- GRB 050916: Swift-BAT refined analysis
- Swift-BAT trigger 155764 is not a GRB
- GRB050916 : Swift-XRT refined analysis
- GRB 050915B: Swift-BAT refined analysis
- GRB 050915: Swift-BAT refined analysis
- GRB050911: Upper limit on X-ray afterglow
- Swift-BAT trigger 155072 ground analysis
- GRB 050908: Swift-BAT refined analysis
- GRB 050908: Optical observations
- GRB 050906: Swift XRT upper limit
- GRB 050904: Keck I-band Imaging
- GRB 050904: early Swift XRT analysis results
- GRB050904: Optical Observations
- GRB 050827: Swift XRT preliminary analysis results
- GRB 050827: P200 NIR Observations
- GRB 050827: Swift-BAT refined analysis
- GRB050824: decay of the XRT light curve and updated X-ray spectrum
- GRB050822: Swift/UVOT upper limits
- GRB 050730, optical observation
- GRB050805b: CrAO optical limit
- GRB050805a : Null detection report
- GRB 050805b: OHP optical limits
- GRB 050730: OHP optical observations
- GRB 050802 : Lulin Optical follow-up observation
- GRB 050730: XRT refined analysis
- Swift/UVOT photometry of GRB050730
- GRB 050730, optical candidate