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"24389 results found.
- GRB 091024: Xinglong TNT optical observation
- GRB 091024: Faulkes Telescope North Afterglow Candidate
- GRB 091024: Swift detection of a burst
- GRB 091020: Additional Lick observations
- Konus-Wind observations of GRB 091010
- GRB 091020: Swift-XRT refined analysis
- GRB 091020: NOT spectroscopic redshift
- GRB 091020: MASTER optical transient polarimetry
- GRB 091020, Swift-BAT refined analysis
- GRB 090926A: Late-time Gemini South Observations and Possible Jet Break
- GRB 091018: Skynet/PROMPT Observations of Fading
- Konus-RF observation of GRB 091018
- GRB 091018: Swift-BAT refined analysis
- GRB 091018: ROTSE-III Detection of Optical Counterpart
- GRB 091015: Skynet/PROMPT Observations
- GRB 091003: Possible Supernova Component
- GRB 090726 R band observations
- GRB 091010: optical afterglow candidate rejection
- GRB 090815: a faint long GRB localized by INTEGRAL
- GRB 091010: Swift-XRT refined analysis
- GRB 091010: Suzaku WAM observation of the prompt emission
- GRB 091010: AGILE-MCAL measurement and GRID upper limit
- GRB 091010: Fermi GBM observation
- GRB 091010: Faulkes Telescope North observations
- GRB 090531A: Skynet/PROMPT Observations
- GRB 090530A: Skynet/DSO Detections
- GRB 091010: RXTE detection
- Konus-Wind observations of GRB 091010
- Detection of a short GRB 090929A by RT-2 Experiment
- RT-2 observation of the bright GRB 090926A
- GRB 091010: Swift/UVOT Upper Limits
- SuperAGILE GRB is 091010 and not 090910
- GRB 090910: SuperAGILE Localization of a Long GRB
- GRB 090518: Skynet/PROMPT Observations
- Short-Duration GRB 090621: Skynet/Dolomiti Observations
- GRB 090904A: afterglow confirmation
- GRB 090812: Skynet/PROMPT and GORT Observations
- GRB 091003A: Suzaku WAM observation of the prompt emission
- GRB 090926B: Skynet/PROMPT Observations
- Konus-Wind observation of GRB 091003A
- GRB 090929B: Suzaku WAM observation of the prompt emission
- GRB 090929A: Suzaku WAM observation of the prompt emission
- GRB 091003: Skynet/DSO Observations
- GRB 091003A: Fermi LAT detection
- GRB 091003A: Fermi GBM detection
- GRB 090929A, Swift-BAT refined analysis
- GRB 090929B, Swift-BAT refined analysis
- GRB 090929A: Swift-XRT non-detection
- Konus-Wind observation of GRB 090929A
- Konus-Wind observation of GRB 090929B
- GRB 090927: Fermi GBM observation
- GRB 090926A: Fermi LAT and GBM refined analysis
- GRB 090929B: Skynet/DSO Observations
- GRB 090929B: Swift/UVOT Observations
- Konus-RF observation of GRB 090929A
- GRB 090929A BAT location of the Fermi GBM burst
- GRB 090929A: Fermi GBM detection
- Konus-Wind and Konus-RF observations of GRB 090926A
- GRB 090926B: Fermi GBM detection
- GRB 090927: Zadko Telescope observations
- GRB 090927, Swift-BAT refined analysis of the possibly short burst
- GRB 090927: Swift XRT refined analysis
- GRB 090926A: Suzaku WAM observation of the prompt emission
- GRB 090927: Swift detection of a short burst
- GRB 090926B: MAXI GSC detection
- GRB 090926B: Swift-BAT refined analysis
- GRB 090926A: Skynet/PROMPT Discovery of the Optical Afterglow
- GRB 090926: Fermi LAT detection
- GRB 090926: Fermi GBM detection
- GRB 090925: Fermi GBM detection
- GRB090922A: correction to Fermi location
- GRB 090922A: Fermi GBM detection
- GRB 090715B: Skynet/PROMPT Detections
- GRB 090726: Skynet/GORT Observations
- GRB 090807: Skynet/DSO Observations
- GRB 090915: GROND upper limits
- Swift-BAT temporarily off-line for a few days
- Short-Duration GRB 090916: Skynet/PROMPT Observations
- GRB 090702: Skynet/GORT Observations
- GRB 090902B: Skynet/PROMPT Observations
- GRB 090916, Swift-BAT refined analysis
- GRB 090915 Swift-BAT detection of a burst in ground analysis
- GRB 090827: Confirmation of the X-ray afterglow
- GRB 090912, Swift-BAT refined analysis
- GRB 090910: Fermi GBM detection
- GRB 090814A: Skynet/DSO & GORT Observations
- GRB 090831A: Suzaku WAM observation of the prompt emission
- GRB 090902B: Suzaku WAM observation of the prompt emission
- GRB 090829A: Suzaku WAM observation of the prompt emission
- GRB 090904B: Fermi GBM detection
- GRB 090904B: Swift-BAT refined analysis
- GRB 090904A: Swift-BAT refined analysis
- GRB090904B: REM observations
- GRB 090904A: ROTSE-III Optical Limits
- GRB090902B: Swift XRT refined analysis
- GRB 090902B: Fermi LAT and GBM refined analysis.
- GRB 090902B: Optical afterglow candidate
- GRB 090902B: Swift/XRT Afterglow Candidate
- GRB 090902B: Fermi LAT detection
- GRB 090902B: Fermi GBM detection of a bright burst