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"
19223 results found.
- GRB061122: Swift-XRT position
- Konus-Wind observation of GRB 061122
- RHESSI Spectrum of GRB061121
- Konus-Wind and Konus-A observations of GRB 061121
- Swift-BAT trigger 239987 is not a GRB
- GRB 061121: Swift/UVOT Observations
- GRB 061121, Swift-BAT refined analysis
- GRB061121, optical observation
- GRB 061121: Optical observation at the KANATA 1.5m telescope
- GRB 061121: Swift detection of a bright burst with an optical counterpart
- GRB 060605: NIR Observations
- GRB 050915B: optical afterglow
- Swift/UVOT Upper Limits for GRB061110b
- Swift/UVOT Upper Limits for GRB061110a
- GRB 061110B, Swift-BAT refined analysis
- GRB061110B: Optical observations at Crni Vrh
- GRB 061110A, Swift-BAT refined analysis
- GRB 061110B: TAROT Calern observatory optical observations
- GRB 061110B: Swift detection of a burst
- GRB 061110: Candidate confirmed
- GRB 061110: ROTSE-III Optical Limits
- GRB 061110: Swift detection of a burst
- GRB061110A - Optical Non-detection
- GRB 061109: TAROT Calern observatory optical observations
- GRB 061027: TAROT La Silla observatory optical observations
- GRB 061028: Swift/XRT Astrometry Correction
- GRB 061102: Swift/UVOT Magnitude Upper Limits
- GRB061102B: Super-LOTIS observations
- GRB 061028: Optical R passband observations
- GRB 061102B: Swift detection of a possible burst
- GRB 061102: Swift detection of a burst
- GRB 061028: VLA Observation
- GRB 061004: Swift/XRT Astrometry Correction
- GRB 060801: Swift/XRT Astrometry Correction
- GRB 061028: Futher P200 Observations
- GRB 061028: P200 Observations
- GRB 061028: SARA upper limit
- GRB 061028: z band imaging
- GRB 061028: Swift/UVOT Observations
- GRB 061028, Swift-BAT refined analysis
- GRB 061028: TAROT Calern observatory optical observations
- GRB 061028: Swift detection of a burst
- GRB 061027, Swift refined analysis of a possible burst
- GRB 061027: Swift detection of a possible burst
- GRB061025: ROTSE-III Confirmation of Optical Counterpart
- GRB061025: Swift/UVOT observations
- GRB 061025: REM observations
- GRB 061025: ROTSE-III Optical Limits
- Konus-Wind observation of GRB 061021
- GRB 061021: Swift-XRT refined analysis
- GRB 061021: Swift/UVOT Observation
- GRB 061021: Swift detection of a burst
- GRB060904b: optical observations
- GRB 061019: SARA upper limit
- GRB 061019: Swift/UVOT upper limit
- GRB 061019, Swift-BAT refined analysis
- GRB 061019: TAROT La Silla observatory optical observations
- GRB 061019: REM K-band candidate afterglow
- GRB 061007: Suzaku/WAM observation of the prompt emission
- GRB 061006: astrometry-corrected XRT position
- Konus-Wind observation of GRB 061007
- GRB061007: Swift UVOT followup observations
- GRB 061006: optical afterglow
- GRB 061006 : Suzaku/WAM observation of the prompt emission
- GRB 061007: OA fading and VLT redshift
- GRB 061007: Swift-BAT refined analysis
- GRB 061007: Swift XRT refined analysis
- GRB 061006: Swift/UVOT optical observations
- Konus-Wind observation of the short hard GRB 061006
- GRB 061007: Swift detection of a burst with an optical counterpart
- GRB 061006: VLT observation
- GRB 060930: near-IR afterglow candidate retraction
- GRB 061006: Swift detection of a burst
- GRB 061004: Optical afterglow candidate and redshift
- GRB 061004: Swift detection of a burst
- Konus-Wind observation of GRB 060928
- GRB 060928: Suzaku/WAM observation of the prompt emission
- IGR J08408-4503 (= V* LM Vel): Swift detection of a transient
- GRB 060928: Swift observations
- GRB 060928: RHESSI Spectral Fit
- IPN triangulation of GRB060928 (long, exceptionally bright)
- GRB 060930: near-IR afterglow candidate
- VLA observations of GRB 060926
- GRB061002 - SDSS Pre-Burst Observations
- GRB 061002: Swift detection of a burst: CORRECTED CONTENT
- GRB 061002: Swift detection of a burst
- GRB 060908: Detection of a possible host
- GRB 060923A: Probable host galaxy in the R-band
- GRB 060807: Detection of a possible host galaxy
- GRB 060923A: VLA K-band Observations
- GRB 060930: Xinglong TNT optical observations
- GRB 060929: Swift/UVOT Optical Observations
- GRB 060930: ROTSE-III Optical Limits
- GRB 060929: TNG K-band observations
- GRB 060929, Swift-BAT refined analysis
- GRB060929: Optical limit
- Liverpool Telescope observations of GRB 060929
- GRB060908: optical observations
- GRB 060927: Swift/UVOT Optical Observations
- GRB 060927 optical limit