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"4900 results found.
- GRB 160927A: Swift-XRT refined Analysis
- GRB 160927A: RTT150 optical afterglow candidate
- GRB 160925A: MITSuME Akeno Optical Observations
- GRB 160917A: Swift/UVOT Detection
- GRB 160917A: Swift-XRT refined Analysis
- GRB 160917A: Mondy optical observations
- GRB 160917A: Enhanced Swift-XRT position
- GRB 160917A: Swift detection of a burst
- GRB 160905A: Swift-XRT refined Analysis
- GRB 160824B: Lomonosov BDRG gamma ray detection and MASTER limit
- GRB 160824B: CALET Gamma-Ray Burst Monitor detection
- GRB 160826A: Swift-XRT refined Analysis
- GRB 160821A: CALET Gamma-Ray Burst Monitor detection
- GRB 160824A: ISON/Terskol optical observations
- GRB 160824A: Swift-XRT refined Analysis
- GRB 160824B: Fermi GBM detection
- GRB 160821B: Swift-XRT refined Analysis
- Short GRB 160821B: MASTER early optical observations
- GRB 160816A: MASTER OT early detection on coaded images
- GRB 160815A: Swift-XRT refined Analysis
- IPN Triangulation of GRB 160806A
- Swift Trigger 707545 is likely 4U 1850-03/GS1843-02
- GRB 160804A: Swift-XRT refined Analysis
- GRB 160801A: Swift-XRT refined Analysis
- GRB 160703, GRB 160705, GRB 160720, SGR1935+2154: First SGRs and GRBs detected by Lomonosov.
- GRB 160716A: Swift-XRT refined Analysis
- GRB 160712A: Swift-BAT refined analysis
- GRB 160714A: MASTER early optical observations
- GRB 160712A: Swift-XRT refined Analysis
- IPN Triangulation of GRB 160702A (short/hard)
- GRB 160705B: Swift-XRT refined Analysis
- GRB 160705A/MAXI J0748-149: MAXI/GSC detection
- GRB 160629A: Global MASTER Net Prompt OT observations
- GRB 160630A: Skynet PROMPT-CTIO observations of the optical afterglow
- GRB 160630A: Swift-XRT refined Analysis
- GRB 160625B: Mini-MegaTORTORA detection of bright optical flash simultaneous with LAT event
- GRB 160625B: TNG redshift confirmation
- GRB 160625A: Swift-XRT refined Analysis
- GRB 160625B: Swift-XRT afterglow detection
- GRB 160623A: SMA submm afterglow observations
- GRB 160625B: Fermi-LAT detection of a bright burst
- GRB 160624A: Lulin observation
- GRB 160623A: TSHAO optical observations
- GRB 160624A: Swift-XRT refined Analysis
- GRB 160624A: MITSuME Ishigakijima upper limits
- GRB 160624A: Fermi GBM observation
- GRB160624A:possible GRB host redshift
- Swift detection of a dust-scattered halo around GRB 160623A
- GRB 160623A: Swift-XRT afterglow detection
- Trigger 701182: Swift detection of SGR 1935+2154
- More FERMI GBM bursts from the magnetar SGR 1935+2154
- GRB 160521A: 15 GHz detections and upper limit from AMI
- Swift Trigger 690738 is not an astrophysical event
- GRB 160611A: Swift-XRT refined Analysis
- GRB160611.9 MASTER-Net OT detection
- GRB 160607A: Swift-BAT refined analysis
- GRB 160607A: Swift-XRT refined Analysis
- Trigger 689353: Swift detection of a transient near Sgr A*
- GRB 160601A: Swift-XRT refined Analysis
- GRB 160530A: Swift follow-up and X-ray afterglow candidate
- GRB 160525B: Swift-XRT refined Analysis
- GRB 160525B: Nanshan optical upper limit
- GRB 160525A: Swift detection of a probable burst
- Another Swift detection of SGR 1935+2154 (trigger #687124)
- GRB 160519A: Swift detection of a burst
- FACT follow-up of the IceCube event 160427A
- Interplanetary Network Search for IceCube 160427A
- GRB 160509A: MAXI/GSC refined analysis
- GRB 160506A: Swift-XRT refined Analysis
- GRB160504A: Gemini NIR Observations
- GRB 160504A: Swift-XRT refined Analysis
- ICECUBE-160427A : Pan-STARRS imaging and optical transients in the field
- VERITAS rapid follow-up observations of IceCube event 160427A
- GRB 160501A: Swift-XRT refined Analysis
- GRB 160501A MASTER-NET early observations
- GRB 160425A: Skynet PROMPT-CTIO observations of the optical afterglow
- GRB 160325A: Skynet PROMPT-CTIO observations of the optical afterglow
- GRB 160425A: GROND observation
- GRB 160425A: Swift-XRT refined Analysis
- LIGO/Virgo G197392 / LVT151012: Identification of a GW CBC Candidate
- GRB 160424A: Fermi GBM observation
- GRB 160424A: Swift-BAT refined analysis
- GRB 160424A: Swift-XRT observations
- GRB 160424A: Swift detection of a burst
- GRB 160422A: Swift-XRT afterglow detection
- GRB 160419A: Fermi GBM detection
- GRB 160417A: Swift-XRT refined Analysis
- LIGO/Virgo G211117: EWE for NOWT of 12 days follow-up of northern sky
- GRB 160409A found in Swift BAT ground analysis
- GRB 160412A: Swift-XRT refined Analysis
- GRB 160410A: further NOT optical observations
- GRB 160411A: Swift-XRT refined Analysis
- GRB 160410A: MITSuME Akeno optical upper limits
- GRB 160410A: Skynet PROMPT-CTIO observations of the optical afterglow
- GRB 160408A: Swift-XRT refined Analysis
- LIGO/Virgo G211117: LOFAR follow-up
- GRB 160324A: CALET Gamma-Ray Burst Monitor detection
- GRB 160327A: JCMT SCUBA-2 sub-mm observation
- GRB 160327A: Swift-XRT refined Analysis
- GRB 160325A: Swift-XRT refined Analysis