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"
18430 results found.
- GRB 120116A: Swift/UVOT Upper Limits
- GRB 120116A: Swift-XRT refined Analysis
- GRB 120116A: Enhanced Swift-XRT position
- AXP 4U 1042+61: Mondy optical observations
- GRB 120116A: Mondy optical observations
- GRB 120116A: EVLA observations
- GRB 120116A: Optical observations at Crni Vrh
- GRB 120116A: Swift-BAT refined analysis
- GRB 120116A: NOT observations
- GRB 120116A: Bassano Bresciano Observatory optical observations
- GRB 120116A: MASTER Early optical limit
- GRB 120116A: Swift detection of a burst
- GRB 120114A found in ground analysis of BAT data
- AXP 4U 0142+61: Swift-BAT refined analysis (trigger 511611)
- GRB 120106A: optical upper limit
- Swift detection of an SGR burst from AXP 4U 0142+61
- IPN Triangulation of GRB 120107A
- GRB 120106A: Swift/UVOT Upper Limits
- GRB 120106A: Bassano Bresciano Observatory optical observations
- GRB 120106A: MASTER Early OT marginally detection
- GRB 120106A: Swift-XRT refined Analysis
- GRB 120106A: Swift-BAT refined analysis
- GRB 120106A: Enhanced Swift-XRT position
- GRB 120106A: TAROT Calern observatory optical observations
- GRB 120106A: MASTER-Tunka optical observations
- GRB 120106A: Swift detection of a burst
- GRB 111222A: Second Swift observation
- GRB111225A: RAPTOR Early Detection of the Optical Counterpart
- GRB 120102A: Fermi GBM observation
- Konus-Wind observation of GRB 120102A
- GRB 120102A: Swift-BAT refined analysis
- GRB 120102A: Swift-XRT refined Analysis
- GRB 120102A: Swift/UVOT Detection
- GRB 120102A: Enhanced Swift-XRT position
- GRB 120102A: Swift detection of a burst with an optical counterpart
- GRB 111228A, optical observations
- Konus-Wind observation of GRB 111228A
- GRB 111229A: Swift/UVOT Detection
- GRB 111229A: Faulkes Telescope South observations
- GRB 111229A: Swift-XRT refined Analysis
- GRB 111229A: Enhanced Swift-XRT position
- GRB 111229A: Swift-BAT refined analysis
- GRB 111229A: Swift detection of a burst
- GRB 111225A: Lightbuckets Optical Observations
- GRB 111228A: P60 Observations
- GRB 111228A: T100 observations
- GRB 111228A: Swift-XRT refined Analysis
- GRB 111228A: PAIRITEL NIR Detection
- GRB 111228A: TAROT La Silla observatory observations
- GRB 111228A: MASTER OT observations
- GRB 111228A: Swift/UVOT Detection
- GRB 111228A, Swift-BAT refined analysis
- GRB 111228A: Enhanced Swift-XRT position
- GRB 111228A: TAROT Calern observatory. OT decay stopped
- GRB 111228A: Fermi GBM observation
- GRB 111228A: TAROT Calern observatory. OT seems still bright
- GRB 111228A: Swift detection of a burst with an optical counterpart
- GRB 111225A: Swift/UVOT Observations
- GRB 111215A: Keck/LRIS Imaging
- GRB 111225A: Keck/LRIS Afterglow Photometry
- GRB 111225A: PAIRITEL NIR Upper Limits
- GRB 111225A: GRT Optical Observation
- GRB 111225A: Swift-XRT refined Analysis
- GRB 111225A, Swift-BAT refined analysis
- GRB 111225A: Enhanced Swift-XRT position
- GRB 111225A: TAROT Calern observatory optical detection
- GRB 111225A: TAROT Calern observatory optical observations
- GRB 111225A: Swift detection of a burst with an optical counterpart
- GRB 111222A: Swift/UVOT Observations
- GRB 111222A: Swift-XRT observations
- IPN Triangulation of GRB 111222A (short/hard/intense)
- Trigger 510075 is not a GRB
- GRB 111215A: EVLA observations
- GRB111215A: CARMA Detection
- XRT GRB Catalogue now live and online
- GRB 111103B: optical upper limit
- GRB 110820A: optical observations in Maidanak observatory
- GRB 111103A: optical upper limit of Mt. Terskol observatory
- GRB 111215B: Suzaku WAM observation of the prompt emission
- GRB111215A: optical upper limit
- GRB 111215B: Swift/UVOT Upper Limits
- GRB 111215B: Swift-XRT observations
- GRB 111205A: Confirmation of X-ray Afterglow
- IPN Triangulation of GRB 111215B (long/intense)
- GRB 111215A: Swift/UVOT Upper Limits
- GRB 111215A: Swift-XRT refined Analysis
- Possible detection of pre-trigger X-ray emission from GRB 111215A by MAXI/GSC
- GRB 111215A: Enhanced Swift-XRT position
- GRB 111215A: Swift-BAT refined analysis
- GRB 111215A: MASTER-Net optical prompt and follow up observations
- GRB 111215A, Optical Observations
- GRB 111209A: RAPTOR Limits Before and During the Gamma-ray Emitting Interval
- GRB 111215A: Swift detection of a burst
- GRB 111212A: GROND observations
- GRB 111211A: Swift/UVOT Detection
- GRB 111212A: Swift-XRT refined Analysis
- GRB 111211A: Swift/XRT target of opportunity observation
- GRB 111212A: Swift/UVOT Upper Limits
- GRB 111212A: Swift-BAT refined analysis
- GRB 111212A: Enhanced Swift-XRT position