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"26274 results found.
- GRB 060906: Early RAPTOR optical limits
- GRB 060906, Swift-BAT refined spectral analysis
- GRB 060906: Swift/XRT Refined Analysis
- GRB 060906: Swift-UVOT observations
- GRB 060906, Swift-BAT refined analysis
- GRB 060906: KAIT observations
- GRB 060906 (?): P60 Optical Afterglow Candidate
- GRB 060906: Swift detection of a probable burst
- GRB 060904B: RTT150 optical observations
- GRB060904A: Swift/UVOT optical observations
- GRB 060904A: pseudo-z from spectral parameters of the prompt emission
- GRB 060904B: Swift-BAT refined analysis
- GRB060904b: Optical observations with Swift/UVOT
- Konus-Wind observation of GRB 060904A
- GRB 060904B: Swift-XRT refined analysis
- GRB 060904A: Refined analysis of the Swift-BAT burst
- GRB 060904A: Swift-XRT refined analysis
- GRB 060904B: Optical observations at Crni Vrh
- GRB 060904B: TAROT optical counterpart observations
- GRB060904B - SDSS Pre-Burst Observations
- GRB 060904: TAROT optical observations
- GRB 060904B: Swift detection of a burst with optical counterpart
- GRB 060904B: ROTSE-III Detection of Optical Counterpart
- GRB060904 - SDSS Pre-Burst Observations
- GRB 060904: Swift detection of a bright burst
- GRB 060901: Swift/XRT Refined Analysis
- Two bright bursts from SGR 1806-20 detected with IBAS
- GRB 060814: Suzaku/WAM observation of the prompt emission
- Swift-BAT trigger 226614 is not a GRB
- GRB060826 - SDSS Pre-Burst Observations
- GRB 060826(?): Swift detection of a possible burst
- GRB 060825: XRT Team Refined Analysis
- GRB 060825: Swift-BAT Refined Analysis
- GRB 060813: Swift/BAT, Konus-Wind, and Suzaku/WAM joint prompt spectral analysis
- GRB060825: Liverpool Telescope optical observations
- GRB 060825: TAROT optical observations
- GRB 060825: Swift detection of a burst
- GRB060814: Break in the XRT light curve
- GRB060813: Break in the XRT light curve
- GRB 060813: A long, bright GRB detected with Suzaku WAM
- Konus-Wind observation of GRB 060814
- GRB 060814: Refined analysis of the Swift-BAT burst
- GRB060814: Swift/UVOT upper limits
- GRB 060814: Swift XRT refined analysis
- GRB 060814 - SDSS Pre-Burst Observations
- GRB 060814: TAROT optical observations
- GRB 060814: Swift detection of a bright burst
- Konus-Wind observation of GRB 060813
- GRB060813: Swift/UVOT upper limits
- GRB 060813: Swift XRT refined analysis
- GRB 060813: Refined analysis of the Swift-BAT burst
- GRB 060813: Swift detection of a burst
- Swift detection of an outburst from the 4U 1246-58 LMXB burster
- GRB060807: Possible Highly Significant X-ray Emission Lines
- GRB 060729: An update on the Swift XRT and UVOT observations
- GRB060807: Optical limiting magnitudes
- GRB 060805B: XRT Team Analysis
- GRB 060807: UVOT Upper limits
- GRB 060807: XRT Team refined analysis
- GRB 060807: Refined analysis of the Swift-BAT burst
- GRB060807: optical upper limit in white light
- GRB060807 - SDSS Pre-burst Observations
- GRB 060805B: X-ray Afterglow Detection, Spectral/Spatial/Temporal Properties
- GRB 060807, optical observation
- GRB 060807: Kanazawa R-band observation
- GRB 060807: Swift detection of a burst
- GRB 060805: optical upper limit in R
- GRB 060805: XRT Team Refined Analysis
- GRB 060805: Swift-BAT Refined Analysis
- GRB 060805: Swift/UVOT Upper Limits
- GRB 060805: KAIT observations
- GRB 060805 - SDSS Pre-Burst Observations
- GRB 060805: Swift detection of a burst
- GRB 060804: Swift UVOT observations
- GRB 060804: Swift-XRT Team Refined Analysis
- GRB 060804: Refined analysis of the Swift-BAT burst
- GRB 060804: Swift detection of a burst with a possible UVOT counterpart
- GRB 060728: Upper limits of the X-ray emission
- GRB060801: Swift/UVOT Upper Limits
- GRB060801: optical upper limit in R
- GRB 060801: Swift XRT refined analysis
- GRB 060801: Refined analysis of the Swift-BAT short hard burst
- GRB 060801: Kanazawa Optical Observation
- GRB 060801: Swift detection of a short burst
- GRB060729: ROTSE-III Observations of the Slow Optical Decay
- GRB 060218 / SN 2006aj Nebular Spectrum
- Swift-BAT trigger 221873 is not a GRB or a Transient
- GRB 060719: TORTOREM optical upper limits
- GRB 060729: Refined analysis of the Swift-BAT burst
- GRB 060729: Swift/UVOT Observations
- GRB 060729: ROTSE-III Detection of Optical Counterpart
- GRB 060729: Swift detection of a burst with an UVOT optical counterpart
- GRB 060728: Swift/UVOT Upper Limits
- GRB 060728: Refined analysis of the Swift-BAT burst
- Swift/XRT preliminary analysis
- GRB 060728: Swift detection of a burst
- GRB 060714: Swift/UVOT Observations
- GRB060719: prompt NIR observations with REM
- GRB 060719: Swift/UVOT Upper Limits
- GRB 060719: VLT/ISAAC observations