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"5386 results found.
- GRB 110128A: Swift detection of a burst
- GRB 101224A, the review of the sky area in plate archives
- GRB 110120A: Fermi GBM detection
- GRB 110106B: MASTER optical observations
- Trigger 441015 / GRB 101225A: Further NOT optical observation
- GRB 101224A - UVOT-enhanced XRT position
- GRB 101219B: GROND Detection of the Optical/NIR Afterglow
- GRB 101219A: GROND Upper limits
- GRB 101219A: Magellan NIR observations
- GRB 101023A: miniTAO/ANIR NIR detection
- GGRB 101023A: GROND detection of the optical-NIR afterglow
- GRB 101008A: optical observations
- GRB 100902A: D50 optical limit
- GRB 101011A: Swift/UVOT Observations of a Possible Optical Afterglow
- GRB 101008A: Swift-BAT refined analysis
- GRB 101008A: Swift/XRT Detection of an Afterglow with no UVOT Counterpart
- GRB 101008A: Swift detection of a burst
- GRB 100924A: Suzaku WAM observation of the prompt emission
- GRB 100924A: Fermi GBM observation
- GRB100925A/MAXI J1659-152 MITSuME Ishigakijima and Okayama Optical Observation
- GRB 100924A: Swift detection of a burst
- GRB 100917A: Swift detection of a burst
- GRB 100906A: GRAS-007 optical observations
- GRB 100906A: Observations at the Virtual Telescope
- GRB 100906A : Faulkes Telescope North optical observations
- Optical observations of GRB 100901A
- GRB 100902A: GROND observations; afterglow candidate
- GRB100902A: Optical upper limits at IAO
- GRB10901A: Optical observations at IAO
- GRB 100901A: Lightbuckets Optical Observations
- GRB 100902A: optical observation at Mt.Terskol
- GRB 100901A: optical observation at Mt.Terskol
- GRB 100829.9: MASTER Optical Limits
- GRB 100814A: Suzaku WAM observation of the prompt emission
- Konus-Wind observation of GRB 100814A
- GRB 100816A: MASTER Optical Limits
- GRB100816A: TNG optical afterglow confirmation.
- GRB 100814A: Fermi GBM observation
- GRB 100814A: GROND Detection of the Optical/NIR Afterglow
- GRB 100814A: Swift UVOT observations of the optical afterglow
- GRB 100814A: Swift detection of a burst with an optical afterglow
- GRB 100814A: ROTSE-III Detection of Optical Counterpart
- Swift-BAT trigger 431582 likely is IGR J17464-2811
- GRB100807A: optical observation in CrAO
- GRB 100807A: P60 Optical Afterglow Discovery
- GRB 100719A: Swift detection of a burst
- GRB 100628A: Near-IR sources coincident with the possible X-ray afterglow
- GRB 100628A: Chandra observations
- GRB 100628A: Swift XRT/UVOT refined analysis
- Konus-Wind observation of GRB 100704A
- GRB 100704A: Fermi GBM observation
- GRB 100704A: Swift detection of a burst
- GRB 100615A: Additional Gemini/NIRI observations
- GRB 100701B: Fermi GBM detection
- GRB 100702A: Swift detection of a short burst
- GRB 100213B: Detection of Fading Optical Afterglow
- GRB 100628A: Gemini North Observations
- GRB 100628A: Swift XRT refined position
- GRB 100628A: Magellan near-IR observations
- GRB 100628A: Swift XRT detection of a possible X-ray afterglow
- GRB 100625A : IRSF/SIRIUS NIR upper limit
- GRB 100625A: Gemini candidate afterglow
- Konus-Wind observation of GRB 100621A
- GRB 100619A: Correction to the Fermi GBM trigger time
- GRB 100621A: GROND observation of bright NIR afterglow
- GRB 100621A: ROTSE-III Optical Limits
- GRB 100621A: Swift detection of a burst
- GRB 100619A: Fermi GBM detection
- XRF 100616a : MAXI/GSC detection of a probable XRF
- GRB 100615A: Swift detection of a burst
- GRB 100513A: CrAO optical observations
- Konus-Wind observation of GRB 100522A
- GRB100522A: Suzaku WAM observation of the prompt emission
- GRB 100522A: Fermi GBM observation
- GRB 100522A: Swift detection of a burst
- GRB 100513A: PAIRITEL NIR afterglow candidate
- GRB100503A: Suzaku WAM observation of the prompt emission
- GRB 100503A: Fermi GBM detection
- GRB 100424A: PAIRITEL NIR Upper Limits
- Swift Trigger 420256: BOOTES-2 observations
- Swift Trigger 420256: ROTSE-III Optical Limits
- GRB100420A: MITSuME optical upper limits
- GRB 100414A: GROND Detection of the Optical Afterglow
- GRB 100413: xinglong TNT optical upper limit
- INTEGRAL trigger 5994 / GRB 100331A: GROND detection of a variable source
- Short X-ray Transient detected by MAXI/GSC
- GRB 100322A: Suzaku WAM observation of the prompt emission
- XRF 100315A: MAXI/GSC detection of a short X-ray transient
- GRB100305A: Optical upper limits at IAO
- GRB 100305A: PAIRITEL NIR Upper Limits
- GRB 100302A: Ondrejov 65cm limit
- GRB 100302A: Optical observations at Crni Vrh
- GRB 100206A: optical observations in Terskol
- GRB 100216A: Swift/UVOT Observations
- GRB 100206A: WHT candidate afterglow
- GRB 100206A: Pre-explosion imaging and host candidate
- GRB 100203A Detected in Ground Analysis of BAT Data
- Swift/BAT Detects an Outburst from XTE J1901+014
- GRB 091221: Enhanced Swift-XRT position
- GRB 091221: UVOT Confirmation of an Optical Afterglow