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"24385 results found.
- GRB060807: Possible Highly Significant X-ray Emission Lines
- GRB060714: optical observations
- IBAS Alert n. 3422: not a GRB
- GRB060717: optical observations
- GRB 060805B: XRT Team Analysis
- GRB060806 is similar to previous activity of SGR1806-20
- GRB 060807: UVOT Upper limits
- GRB 060807: afterglow confirmation
- GRB 060807: XRT Team refined analysis
- GRB 060807: K- and R-band observations
- GRB 060807: Refined analysis of the Swift-BAT burst
- GRB 060805B: RHESSI Spectral Fit
- GRB 060805B: X-ray Afterglow Detection, Spectral/Spatial/Temporal Properties
- GRB060805 Liverpool Telescope observations
- GRB 060805: Swift-BAT Refined Analysis
- GRB 060805: Swift/UVOT Upper Limits
- GRB 060805: Swift detection of a burst
- GRB 060804: Swift UVOT observations
- GRB 060804: Refined analysis of the Swift-BAT burst
- GRB 060801: no variability of optical sources
- IBAS Alert 3418: not a GRB
- GRB 051109B: Bright spiral host galaxy at low redshift
- GRB060801: Swift/UVOT Upper Limits
- GRB 060801: optical observations at Hanle and Calar Alto
- GRB 060801: Refined analysis of the Swift-BAT short hard burst
- GRB 060801: Swift detection of a short burst
- IBAS Alert n. 3415: not a GRB
- GRB 060729 redshift
- GRB 060729: Refined analysis of the Swift-BAT burst
- GRB 060729: Swift-XRT refined analysis
- GRB 060729: ROTSE-III Detection of Optical Counterpart
- GRB 060728: Swift/UVOT Upper Limits
- GRB 060728: Refined analysis of the Swift-BAT burst
- GRB 060728, SMARTS optical/IR observations
- GRB060719: prompt NIR observations with REM
- GRB 060719: near-infrared afterglow
- GRB 060719: Swift/UVOT Upper Limits
- GRB 060719: Refined analysis of the Swift-BAT burst
- GRB 060719: further analysis of VLT observations
- GRB060719: FRAM early follow-up limit
- GRB 060719: prompt PROMPT observations
- GRB 060714: Refined analysis of the Swift-BAT burst
- GRB060717: Swift/UVOT upper limits
- GRB 060717: Swift-BAT refined analysis
- GRB 060714: REM infrared observations
- GRB 060717: Swift detection of a burst
- GRB 060714, SMARTS optical/IR afterglow observation
- GRB 060605: SkyNet Optical Limits
- GRB 060712: XRT refined analysis
- GRB 060712: Swift/UVOT Upper Limits
- GRB 060712: Refined analysis of the Swift-BAT burst
- GRB060712: MASTER optical observation
- GRB120706: MASTER optical observation
- GRB 060708: PROMPT Optical Limits
- GRB 060708: Swift-XRT refined analysis
- GRB 060708: Refined analysis of the Swift-BAT burst
- GRB 060707: Swift-XRT refined analysis
- GRB 060707: Refined analysis of the Swift-BAT burst
- GRB 060515: Upper Limit on Host Galaxy
- GRB 060614: SMARTS host galaxy observations
- GRB 060614: Detection of a Possible, Late-Time Rebrightening
- GRB 060109: Upper Limit on Host Galaxy
- GRB 060105: Upper limit on Host Galaxy
- GRB060614: Detection of the host galaxy but no supernova emission
- GRB 060614: redshift confirmation
- GRB060512: near IR observations
- GRB060526: optical observations
- Konus-Wind observation of GRB 060614
- GRB060605: optical observation
- GRB 060605, optical observations
- GRB 060614, SMARTS optical/IR afterglow observation
- GRB 060614: Swift-BAT refined analysis
- GRB060614: Swift-XRT refined analysis
- GRB 060604, optical observations
- GRB 060607B: Swift-BAT Refined Analysis
- GRB060602A: Swift/UVOT upper limits
- GRB 060607: Swift-BAT Refined Analysis
- GRB 060607: PROMPT Observations
- GRB 060522: PROMPT Optical Limits
- GRB 060605 BAT refined analysis
- GRB060602B : REM infrared observations
- GRB 060605: ROTSE-III Detection of Optical Counterpart
- GRB 060512: Keck Redshift
- GRB 060604: Swift-XRT Team refined analysis
- GRB 060604: BAT refined analysis
- GRB 060604A: ROTSE-III Optical Limits
- GRB 060602B: Swift-BAT Refined Analysis
- GRB 060602A: Swift-BAT Refined Analysis
- GRB 060526: Tautenburg Second Epoch Observations
- GRB 060526: Break in X-ray light curve
- GRB 060526: Multiple Optical Flares
- GRB060526: afterglow fitting and probable jet break
- GRB060502b: optical observations
- GRB060526: optical observations
- GRB 060526: SMARTS optical/IR afterglow observations
- GRB 060526: REM observations
- GRB 060526: Optical Flare
- GRB 060526: Refined analysis of the Swift-BAT burst
- GRB060526, optical observations
- GRB 060526: Swift/XRT Team refined analysis