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"
18435 results found.
- GRB 121212A: optical observations in ISON-NM observatory
- GRB121212A: Swift/UVOT Detection
- GRB 121212A: Swift-BAT refined analysis
- GRB 121211A: Swift-BAT refined analysis
- GRB 121212A: Enhanced Swift-XRT position
- GRB 121212A: A long GRB detected by INTEGRAL
- GRB 121212A: Swift detection of a burst
- GRB 121211A: Swift/UVOT Detection
- GRB 121211A: Swift-XRT refined Analysis
- GRB 121211A: Enhanced Swift-XRT position
- GRB 121211A: Swift detection of a burst with an optical counterpart
- GRB 121209A: CARMA 3mm Observations
- GRB 121209A: EVLA Observations
- GRB 121209A: Swift-XRT refined Analysis
- GRB 121209A: Swift-BAT refined analysis
- GRB 121209A: Enhanced Swift-XRT position
- GRB 121209A: GROND optical afterglow candidate
- GRB 121209A: PAIRITEL NIR Observations
- GRB 121209A: UVOT Observation
- GRB 121209A: Swift detection of a burst
- GRB 121127A: Suzaku WAM observation of the prompt emission
- GRB 121128A: Optical Observations
- GRB 121122A: Suzaku WAM observation of the prompt emission
- GRB 121202A: Swift/UVOT Upper Limits
- GRB 121202A: Swift-XRT refined Analysis
- GRB 121202A: Fermi GBM observation
- GRB 121202A: Enhanced Swift-XRT position
- GRB 121202A: Swift-BAT refined analysis
- GRB 121202A: Swift-XRT observations
- GRB121202A: Swift/UVOT Observations
- GRB 121202A: TAROT Calern observatory optical observations
- GRB 121202A: Swift detection of a burst
- GRB 121201A: GROND afterglow observations and photometric redshift
- GRB 121201A: Swift/UVOT Detection
- GRB 121201A: Swift-XRT refined Analysis
- GRB 121201A: Swift-BAT refined analysis
- GRB 121201A: Enhanced Swift-XRT position
- GRB 121201A: a GRB with an optical counterpart
- GRB 121128A: optical observation in Mondy observatory
- IPN Triangulation of GRB 121127A (short/hard)
- GRB 121128A: optical observation in Mondy observatory
- GRB 121128A: Swift/UVOT Detection
- GRB 121128A: Swift-XRT refined Analysis
- GRB 121128A: Enhanced Swift-XRT position
- GRB 121128A: RAPTOR Detection During Gamma-Ray Emitting Interval
- GRB 121128A: Fermi GBM observation
- GRB 121128A, Swift-BAT refined analysis
- Konus-Wind observation of GRB 121128A
- GRB 121128A: Swift detection of a burst with an optical counterpart
- GRB 121123A: Suzaku WAM observation of the prompt emission
- GRB 121123A: Swift/UVOT Observations
- GRB 121125A: Swift/UVOT Detection
- IPN Triangulation of GRB 121122A (long/intense)
- GRB 121125A: Swift-XRT refined Analysis
- GRB 121125A: Enhanced Swift-XRT position
- GRB 121125A: Fermi GBM Observation
- GRB 121125A: Swift-BAT refined analysis
- GRB 121125A: MASTER-NET optical observations
- GRB 121125A: Swift detection of a burst with optical counterpart
- GRB 121123A: GROND observations
- GRB 121123A: Enhanced Swift-XRT position
- GRB 121123A: Swift-BAT refined analysis
- GRB 121123A: Swift-XRT refined Analysis
- GRB 121123A: optical observations
- GRB 121123A: Fermi GBM observation
- GRB 121123A: MASTER-NET optical limit
- GRB 121123A: Swift detection of a burst with optical counterpart
- GRB 121108A: optical upper limit
- IPN Triangulation of GRB 121118B (long/intense)
- GRB 121117A: GROND confirmation of the UVOT afterglow candidate
- Swift-BAT trigger 538575 is not astrophysical
- GRB 121117A: Swift/UVOT Observations
- GRB 121117A: Swift-XRT refined Analysis
- GRB 121117A: MASTER prompt optical limit
- GRB 121117A, Swift-BAT refined analysis
- GRB 121117A: ROTSE-III Optical Limits
- GRB 121117A: BOOTES-3 early optical upper limit
- GRB 121117A: Swift detection of a burst
- Swift trigger 538575: Magellan Observations
- Trigger 538084: Swift detection of XTE J1739-302
- GRB 121108A: Swift-XRT refined Analysis
- GRB 121108A: Swift/UVOT Upper Limits
- GRB 121108A, Swift-BAT refined analysis
- GRB 121108A: Enhanced Swift-XRT position
- GRB 121108A: Optical observations
- GRB 121108A: MASTER early prompt optical limit
- GRB 121108A: TAROT Calern observatory optical observations
- GRB 121108A: Swift detection of a burst
- GRB 121031A: Fermi GBM detection
- GRB 121028A: Swift/UVOT Upper Limits
- GRB 121031A, Early peak observed with Swift-BAT
- GRB 121102A: Swift/UVOT Upper Limits
- GRB 121031A: Swift/UVOT Upper Limits
- GRB 121031A: Swift-XRT refined Analysis
- GRB 121102A: Enhanced Swift-XRT position
- GRB 121031A: Enhanced Swift-XRT position
- GRB 121102A: Swift-XRT refined Analysis
- GRB 121102A: Swift-BAT refined analysis
- GRB 121025A: Confirmation of the X-ray afterglow
- GRB 121102A: Swift detection of a burst