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"28092 results found.
- GRB 130925A: VLT/UVES observations
- GRB 130925A: MAXI/GSC detection
- GRB 130925A: GROND afterglow candidate
- GRB 130925A: Swift detection of a burst
- IPN Triangulation of SGR-like burst 130913 - probable association with SGR/AXP 1E1841-045
- GRB 130831A: RTT150 optical observations
- GRB 130831A: RATIR Confirmation of NIR/Optical Afterglow Flattening
- GRB 130903A: optical observations
- GRB 130907A: Maidanak optical observations
- GRB 130912A: AAO optical upper limit
- Fermi Trigger 401326696: MASTER prompt optical observations
- GRB 130919A: Skynet PROMPT-CTIO optical upper limits
- GRB 130919A, Swift-BAT refined analysis
- GRB 130913A detected in ground analysis of Swift-BAT data
- GRB 130912A: Swift/UVOT Upper Limits
- Fermi/GBM Detection of two SGR-like bursts possibly associated with SGR J1833-0832
- GRB 130912A: 5.8 GHz VLA upper limit
- GRB 130912A: RATIR Optical and NIR Upper Limits
- GRB 130907A: Continued RATIR Optical and NIR Observations
- GRB 130912A: P60 Observations
- GRB 130912A: Swift-XRT refined Analysis
- GRB 130907A: MASTER refined analysis
- GRB 130912A: Fermi GBM detection
- GRB 130912A: Skynet DSO-14/Yerkes-41/PROMPT-CTIO observations
- GRB 130912A: Enhanced Swift-XRT position
- GRB 130912A, Swift-BAT refined analysis
- GRB 130912A: REM optical/NIR upper limits
- GRB 130912A: GROND observations
- GRB 130912A: Swift detection of a short burst
- GRB 120419A: Swift XRT confirmation of the afterglow
- GRB 130907A: Continued RATIR Optical and NIR Observations
- GRB 130907A: RATIR Optical and NIR Observations
- GRB 130828A: Further Swift XRT observations
- GRB 130907A: Further Swift-BAT refined analysis
- GRB 130907A: INTEGRAL/SPI-ACS light curve
- GRB 130907A, Swift-BAT refined analysis
- GRB 130907A: Swift-XRT refined Analysis
- GRB 130907A: Enhanced Swift-XRT position
- GRB 130907A: Swift/UVOT Detection
- GRB 130907A: Early Tautenburg detections, red afterglow
- GRB 130907A: Skynet DSO-14/Yerkes-41/GORT confirmation of a fading afterglow
- GRB 130907A: RATIR Optical and NIR Afterglow Confirmation
- GRB 130907A: Skynet DSO-14/Yerkes-41 detections of a possible afterglow
- GRB 130831A: Maidanak optical observations
- GRB 130831A: optical observation in Chuguev AO
- GRB 130831A: ISON-Kislovodsk optical observations
- GRB 130831A: optical observation in Gissar AO
- GRB 130831A: ISON-UAFO optical observations
- GRB 130907A: Swift detection of a burst with an optical counterpart
- Swift follow-up results of the possible weak INTEGRAL GRB
- GRB 130903A: Swift/UVOT Upper Limits
- Swift follow-up of an INTEGRAL possible weak GRB
- GRB 130831A: RATIR Optical and NIR Upper Limits
- GRB 130903A: GROND Afterglow Discovery
- GRB 130903A: Fermi GBM observation
- GRB 130903A: Swift-XRT observations
- GRB 130903A: ISON-Kislovodsk optical Upper Limits
- GRB 130903A: GROND Upper Limits
- GRB 130831A: Swift/UVOT Observations
- GRB 130831A: Optical Observations via Virtual Telescope, follow-up
- GRB 130831A: RATIR Optical and NIR Observations
- GRB 130831A: Continued Skynet/PROMPT-SSO, PROMPT-CTIO and Yerkes-41 detections
- GRB 130831B, Swift-BAT refined analysis
- GRB 130831A: T100 observations
- GRB 130831B: Swift/UVOT Upper Limits
- GRB 130831B: GROND upper limits
- Swift Trigger 569022: a possible GRB
- GRB 130831A, Swift-BAT refined analysis
- GRB 130831B: Swift-XRT refined Analysis
- GRB 130831A: Optical Observations via Virtual Telescope
- GRB 130831A: Swift-XRT refined Analysis
- GRB 130831B: Enhanced Swift-XRT position
- GRB 130831A: Skynet/PROMPT-SSO detections
- GRB 130831A: Enhanced Swift-XRT position
- GRB 130831A: MITSuME Akeno Optical observation
- GRB 130831A: Weihai optical observations
- GRB 130831B: Swift detection of a burst
- GRB 130831A: Faulkes Telescope North and South optical afterglow
- GRB 130831A: Swift detection of a burst with an optical counterpart
- GRB 130822A: optical upper limits
- GRB 130829A: AAO optical observations
- GRB 130828A: Swift XRT and UVOT observations
- GRB 130829A: NOT optical observations
- IPN triangulation of GRB 130828A
- GRB 130829A: Swift detection of a burst
- GRB 130828A: Fermi GBM detection
- GRB 130828A: Fermi-LAT detection of a burst
- GRB 130822A Swift-BAT Spectral lag analysis
- GRB 130821A: Weihai optical upper limit
- GRB 130821A: Swift-XRT observation
- GRB 130822A: 5.8 GHz VLA upper limit
- GRB 130822A: Swift-XRT refined Analysis
- GRB 130822A: Swift/UVOT Upper Limits
- GRB 130822A: Enhanced Swift-XRT position
- GRB 130822A, Swift-BAT refined analysis
- GRB 130821A: Fermi-LAT detection of a burst
- GRB 130822A: Weihai optical upper limit
- GRB 130821A: Fermi GBM Detection
- GRB 130822A: Swift detection of a short burst
- GRB 130816A: Swift/UVOT Upper Limits