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"8473 results found.
- GRB 100115A: SARA Astrometry
- NOT observation of GRB100115A localization
- GRB 100115A: SARA Afterglow Candidate
- GRB 100115A: Swift/UVOT Upper Limits
- GRB 100115A: Swift-XRT candidate afterglow
- GRB 100111A: Swift-BAT refined analysis
- GRB 100111A: Swift detection of a burst with an optical afterglow
- GRB 100103A: Swift/UVOT Upper Limits
- GRB 091231: GROND NIR observations
- Trigger 381591: Swift detection of a possible burst
- GRB 091230: Swift-XRT observation
- GRB 091230: GROND optical/NIR afterglow candidate
- Trigger 381434: Swift detection of a possible burst
- GRB 091221: ROTSE-III Detection of Optical Counterpart
- GRB 091221: Swift detection of a burst
- Swift trigger 379449 (possible GRB) is not a burst
- Trigger 379449: Swift detection of a possible burst
- GRB 091208B: Swift detection of a burst with an optical afterglow
- GRB 091202: GTC & CAHA optical/nIR afterglow candidate
- GRB 091117: Chandra Observations
- Swift trigger 377436 (possible GRB 091130A) is not a burst
- GRB 091130B: Swift detection of a burst
- GRB 091130: Swift detection of a possible burst
- GRB 091127 : GROND observations
- GRB 091127: Swift/UVOT Detection of an Optical Afterglow
- GRB 091127: Liverpool Telescope afterglow candidate
- GRB091117: Gemini South Observations
- GRB 091109B: Swift detection of a short burst
- GRB 091109: Faulkes Telescope South observations
- GRB 091109: Swift detection of a burst with optical afterglow
- GRB 091104: Swift detection of a burst
- GRB 091102 : Faulkes Telescope South Upper Limits
- GRB 091102: GROND Upper Limits
- GRB 091102: Swift/XRT localization
- GRB 091102: Swift/UVOT Finding Chart Observation
- GRB 091024: optical observations
- GRB 091029: Gemini-South Redshift
- GRB 091029: Swift detection of a burst with an optical counterpart
- GRB 091026: Swift-BAT refined analysis
- GRB 091026: Swift detection of a Gamma Ray Burst
- GRB 091024: Swift-XRT team refined analysis
- GRB 091024: Faulkes Telescope North Afterglow Candidate
- GRB 090926A: Late-time Gemini South Observations and Possible Jet Break
- GRB 091020: Swift detection of a burst with an optical afterglow
- GRB 091018: miniTAO/ANIR Observations
- GRB 091018 : Faulkes Telescope South Observations
- GRB 091018: GROND observations
- GRB 091018: ROTSE-III Detection of Optical Counterpart
- GRB 091018: Swift detection of a burst with optical afterglow
- Fwd: GRB 091003: Possible Supernova Component Retraction
- GRB 091003: Possible Supernova Component
- GRB 091010: optical obsevation
- GRB 091010: optical afterglow candidate rejection
- GRB 091010: Faulkes Telescope North observations
- GRB 091010: RXTE detection
- GRB 091010: Enhanced XRT position
- GRB 091010 optical upper limits
- GRB 091010: GROND afterglow candidate
- GRB 090910: SuperAGILE Localization of a Long GRB
- GRB 091003: Swift UVOT Detection of a Candidate UV Afterglow
- GRB 090929B: Gemini-N upper limits
- GRB 090929B: Swift detection of a burst
- GRB 090927: Faulkes Telescope South Detection of the Optical Afterglow
- GRB 090926B: VLT spectroscopy
- GRB 090927: Swift/UVOT detection of an optical afterglow
- GRB 090926A: Swift/UVOT detection of an optical afterglow
- GRB 090926B: Swift detection of a burst
- GRB 090925: Fermi GBM detection
- GRB 090915: SARA detection of afterglow candidate
- GRB 090912: optical observation
- GRB 090915: Swift/UVOT detection of an optical afterglow candidate
- GRB 090912: Swift detection of a burst
- GRB 090904A: Swift-BAT refined analysis
- GRB 090902B: WSRT Radio Observation
- GRB 090904B: Swift detection of a burst
- GRB 090904: Swift detection of a burst
- GRB 090902B: Faulkes Telescope North observations
- GRB 090902B: Optical afterglow candidate
- GRB090902B: Swift/UVOT observations
- GRB 090902B: Swift/XRT Afterglow Candidate
- GRB 090831C: Swift detection of a burst
- GRB 090831B: Swift detection of a possible burst
- Konus-Wind observations of GRB 090827
- GRB 090817 - TLS Observations
- GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
- GRB 090817: Swift-XRT observations
- GRB 090814: GROND Detection of an Optical Afterglow Candidate
- GRB 090814: Swift detection of a burst
- GRB 090813: optical candidate from 1.23m CAHA telescope
- GRB 090813: Swift detection of a burst
- GRB 090812: Swift detection of a burst with an optical counterpart
- GRB 090809: Swift detection of a burst with a possible optical counterpart
- GRB 090807: Swift detection of a burst
- GRB 090802: Fermi GBM detection
- Swift trigger 358760 is probably a noise event
- GRB 090709A : Quick look analysis of the Suzaku observation
- GRB 090728A: Faulkes Telescope North Optical Afterglow Candidate
- GRB 090728: Swift detection of a burst
- GRB 090727: Swift-BAT refined analysis
- GRB 090727: Liverpool Telescope possible OT candidate