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"19602 results found.
- GRB 230415A: Swift/BAT-GUANO detection
- GRB 230307A: iTelescope optical upper limit (likely)
- GRB 230414B: Montarrenti Observatory late time optical afterglow detection
- GRB 230414B: Lulin 40cm-SLT optical limit
- GRB 230414B: Bassano Bresciano Observatory optical observations
- GRB 230414B: AbAO optical observations
- GRB 230409B: 3.6m DOT near-infrared detection, afterglow confirmation
- GRB 230414B: Swift-XRT refined Analysis
- GRB 230414B: Dabancheng/GHOST optical observations
- GRB 230414B: SAO RAS optical observations
- GRB 230414B: Enhanced Swift-XRT position
- GRB 230414B: 1.3m DFOT Optical observations
- GRB 230414B: GROWTH India Telescope afterglow confirmation
- GRB 230414B: Nanshan/HMT optical afterglow detection
- GRB 230414A: Mondy optical afterglow candidate
- Swift GRB 230414B: Global MASTER-Net observations report
- GRB 230414B: Prompt enhanced Swift-XRT position
- GRB 230414B: Swift detection of a burst
- GRB 230328B: redshift lower limit estimating
- GRB 230409B: Mondy optical upper limit
- GRB 230409B: Swift-XRT refined Analysis
- GRB 230409B: Swift-BAT refined analysis
- Swift GRB 230409B: Global MASTER-Net observations report
- GRB 230409B: Swift/UVOT Detection
- GRB 230409B: Enhanced Swift-XRT position
- GRB 230409B: Swift detection of a burst
- GRB 230405B: VZLUSAT-2 detection
- Konus-Wind detection of GRB 230405B
- GRB 230405B: AGILE detection
- GRB 230405B: Swift-XRT refined Analysis
- GRB 230405B: Fermi GBM Observation
- GRB 230405B: MeerLICHT upper limits
- GRB 230405B: Swift/UVOT Upper Limits
- GRB 230405B: AstroSat CZTI detection
- GRB 230405B: Enhanced Swift-XRT position
- Swift GRB 230405B: Global MASTER-Net observations report
- GRB 230405B: Prompt enhanced Swift-XRT position
- GRB 230405B: Swift detection of a burst
- GRB 230307A: Chandra late-time detection of the X-ray afterglow
- GRB 230228A: detection by GTC of the potential host galaxy
- GRB 230328B: Swift/UVOT Detection
- GRB 230328B : GRANDMA/Kilonova-Catcher optical detection
- GRB 230328B: CAHA 2.2m/CAFOS detection
- GRB 230328B: 3.6m DOT multiband optical observation
- Konus-Wind detection of GRB 230328B
- GRB 230328B: GRBAlpha detection
- GRB 230328B: Swift-BAT refined analysis
- GRB 230328B: Nanshan/NEXT 2nd optical observation
- GRB 230328B: Liverpool Telescope afterglow detection
- GRB 230328B: GIT optical follow-up
- GRB 230328B: OASDG optical observations
- GRB 230328B: Nanshan/NEXT optical upper limit
- GRB 230328B: Swift-XRT refined Analysis
- GRB 230328B: AstroSat CZTI detection
- GRB 230328B: Fermi GBM observation
- GRB 230328B: Mondy, AbAO and Kitab optical observations
- GRB 230328B: Enhanced Swift-XRT position
- GRB 230328B: Mondy optical afterglow confirmation
- GRB 230328B: Swift detection of a burst with an optical afterglow
- GRB 230325A: Swift-BAT refined analysis
- GRB 230325A: Swift/UVOT Upper Limits
- GRB 230325A: Swift-XRT refined Analysis
- GRB 230322B: Swift-BAT refined analysis
- GRB 230325A: Enhanced Swift-XRT position
- GRB 230325A: Prompt enhanced Swift-XRT position
- GRB 230325A: Swift detection of a burst
- GRB 230320B: Fermi GBM Observation
- GRB 230322B: Swift/UVOT Detection
- GRB 230322B: Swift-XRT refined Analysis
- GRB 230322B: Enhanced Swift-XRT position
- Swift GRB 230322B: Global MASTER-Net observations report
- GRB 230322B: Swift detection of a burst with optical counterpart
- GRB 230320B: GRBAlpha detection
- GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
- Trigger 1160641: Swift detection of 4U 1630-472 (a.k.a. SWIFT J1633.8-4724A)
- IPN triangulation of GRB 230309A
- VZLUSAT-2 detection of SGR 1806-20
- GRB 230307A: Swift/UVOT detection
- GRB 230307A: soft X-ray detection with LEIA
- GRB 230307A: Swift-XRT afterglow detection
- Swift GRB230311.85: Global MASTER-Net observations report
- Swift GRB230311.83: Global MASTER-Net observations report
- Further improved IPN localization for GRB 230307A
- Swift GRB230311.81: Global MASTER-Net observations report
- GRB 230307A: SOAR/Goodman detection of the possible host galaxy
- Swift GRB230311.84: Global MASTER-Net observations report
- Swift Trigger 1159438 is also due to the Star Tracker loss of lock.
- Swift GRB230311.82: Global MASTER-Net observations report
- Triggers 1159434, 1159435 and 1159437: Swift detection of Sco X-1 due to Star Tracker loss of lock
- Trigger 1159327: Swift detection of SGR1806-20
- GRB 230307A: MAXI/GSC upper limit
- GRB 230307A: Possible optical afterglow
- GRB 230307A: ASO-S/HXI detection
- GRB 230307A: optical upper limit
- GRB 230217A: ATCA rapid-response radio detection
- Swift Trigger 1159108 is not a GRB
- GRB 230307A: Swift/BAT upper limits on the early afterglow
- GRB 230307A: Swift-XRT observations
- Improved IPN localization for GRB 230307A
- GRB 230307A: Tiled Swift observations