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.
- GRB 061002, Swift-BAT refined analysis
- GRB061002: MASTER-VWF-Kislovodsk observations
- GRB060930: Faulkes Telescope South observation
- GRB 060930: Xinglong TNT optical observations
- GRB 060929: Swift/UVOT Optical Observations
- GRB 060930: ROTSE-III Optical Limits
- GRB 060930: A long X-ray rich GRB detected by INTEGRAL
- GRB060929: Swift-XRT refined analysis.
- GRB 060929, Swift-BAT further refined analysis - late-time flare
- GRB 060929, Swift-BAT refined analysis
- GRB 060929: BART observation
- GRB 060929: MASTER-VWF-Kislovodsk observations
- GRB 060929: Swift detection of a burst
- GRB060908: optical observations
- GRB 060729: An update on the late-time Swift observations
- IBAS Alert n.3501: not a GRB
- IBAS Alert n.3500: not a GRB
- GRB060923C: optical limit
- GRB060927: optical observations
- GRB 060926: Swift-UVOT UVW1 Detection Retraction
- GRB 060927: Early color
- GRB 060927, Swift-BAT refined analysis
- GRB 060927: Xinglong TNT optical observations
- GRB060927: Faulkes Telescope South observation
- GRB 060926: MASTER: first minutes decay
- GRB 060927A: ROTSE-III Detection of Optical Counterpart
- GRB 060927: Swift detection of a burst
- GRB 060926: OPTIMA-Burst -- further observations
- GRB 060926: Swift XRT refined analysis
- GRB 060926, Swift-BAT refined analysis
- GRB 060926: MASTER OT alert observation
- GRB 060926: MASTER optical observation
- GRB 060923C, Swift-BAT refined analysis
- GRB060923C: AROMA optical obsevation
- GRB 060923C: Gemini Observations and Afterglow Candidate
- GRB 060923A: Gemini Second Epoch and Afterglow Confirmation
- GRB060923B: Swift/UVOT upper limits
- GRB 060923C: Swift XRT refined analysis
- GRB 060923A: Keck and Gemini Observations
- GRB 060923B, Swift-BAT refined analysis
- GRB060923C: Faulkes Telescope North optical observations
- GRB 060923B: Swift detection of a burst
- GRB 060923, Swift-BAT refined analysis
- GRB060923: Faulkes Telescope North optical observations
- Swift detects a hard X-ray burst from AXP CXOU J164710.2-455216
- GRB 060919, Swift-BAT refined analysis
- GRB 060912A: Probable Host Galaxy
- IBAS Alert n.3470: not a GRB
- Konus-Wind observation of GRB 060912
- IBAS Alert No.3468: not a GRB
- GRB 060912B: a long GRB detected with INTEGRAL
- GRB 060912: Swift XRT Team Refined Analysis
- GRB 060912, Swift-BAT refined analysis
- GRB 060908, Swift-BAT refined analysis
- GRB 060904A : Optical limit
- GRB 060908: REM optical prompt observation
- GRB 060908: PROMPT Detection of a Bright Counterpart
- GRB 060904A: Suzaku/WAM observation of the prompt emission
- GRB060904b optical detections (delayed report due to internet outage)
- GRB 060906, Swift-BAT refined spectral analysis
- GRB 060906: Swift/XRT Refined Analysis
- VLT redshift of GRB 060906
- GRB 060906: observations with FRAM
- GRB 060906: Swift detection of a probable burst
- GRB 060904b: SMARTS optical/IR afterglow observations
- GRB 060904A: Subaru NIR observation
- GRB 060904A: pseudo-z from spectral parameters of the prompt emission
- GRB 060904B: Swift-BAT refined analysis
- GRB 060904B: Swift-XRT refined analysis
- GRB 060904A: Refined analysis of the Swift-BAT burst
- GRB 060904A: Swift-XRT refined analysis
- GRB 060904B: VLT redshift
- GRB 060904B: ROTSE-III Detection of Optical Counterpart
- Konus-Wind observation of GRB 060901
- GRB 060901: Swift/XRT Refined Analysis
- GRB 060901: SMARTS optical/IR observations
- GRB 060901: further INTEGRAL results
- GRB 060901: a long GRB detected by INTEGRAL
- Two bright bursts from SGR 1806-20 detected with IBAS
- GRB 060814: Suzaku/WAM observation of the prompt emission
- 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
- GRB060729: analysis of XMM-Newton observation
- GRB 060814: pseudo-z from spectral parameters of the prompt
- IBAS Alerts No 3429 and 3430: not GRBs
- GRB 060729, SMARTS optical/IR observations
- GRB 060813: A long, bright GRB detected with Suzaku WAM
- GRB 060814: Refined analysis of the Swift-BAT burst
- GRB 060814: P60 Observations
- GRB060814: Swift/UVOT upper limits
- GRB 060814: VLT optical limits
- 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
- GRB051109B: Late-time Radio Observations
- A dust-scattering halo detected around SGR 1806-20
- Swift detection of an outburst from the 4U 1246-58 LMXB burster