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"11748 results found.
- EP260214b: Optical upper limit with Kinder observations
- EP260214a: Optical upper limits with Kinder observations
- EP260214b: EP-FXT follow-up observation
- EP260214a: COLIBRÍ optical upper limits
- EP260214a: refined analysis of the EP-FXT observation
- EP260214b: Einstein Probe detection of a fast X-ray transient
- EP260214a: Einstein Probe detection of an X-ray transient
- GRB 260212A: AstroSat CZTI detection
- EP260213a: Optical upper limits with Kinder observations
- EP260213a: Mondy R-band optical upper limit
- EP260213a: NUTTelA-TAO Early Optical Limits
- EP260213a: refined analysis of the EP-FXT observation
- EP260213a: Einstein Probe detection of a fast X-ray transient
- GRB 260211A: GOTO optical upper limit
- Konus-Wind detection of GRB 260207B
- GRB260131A/B: 3.6m DOT Optical Observations
- GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
- GRB 260211A: SVOM detection of a burst
- Konus-Wind detection of GRB 260209B
- Konus-Wind detection of GRB 260127B
- EP260210a: Global MASTER-Net observations report
- EP260210a: refined analysis of the EP-FXT observation
- EP260209a: Einstein Probe detection of a fast X-ray transient
- EP260210a: Optical upper limits with Kinder observations
- GRB 260208C: AstroSat CZTI detection
- EP260210a: COLIBRÍ optical upper limit
- EP260210a: Einstein Probe detection of an X-ray transient
- GRB 260207B: AstroSat CZTI detection
- GRB 260208B: AstroSat CZTI detection of a bright long burst
- Fermi GRB 260209A: Global MASTER-Net observations report
- GRB 260208A: Mondy optical observations
- GRB 260208A: 1.3m DFOT optical detection
- GRB 260208B: EP-FXT observation
- Fermi GRB 260208C: Global MASTER-Net observations report
- GRB 260208B: Fermi-LAT detection
- GRB 260208A: Fermi-LAT detection
- Fermi trigger No 792135758: Global MASTER-Net observations report
- GRB 260206A (or XRB from 4U 0513-40): MAXI/GSC detection
- GRB 260204A: Swift-XRT observations
- GRB 260204A : MASTER Global robotic net optical observations
- GRB 260204A: SVOM detection of a burst
- GRB 260121A: 239Alferov CubeSat detection
- Konus-Wind detection of GRB 260121A
- GRB 260131A/B: GTC/OSIRIS+ redshift confimation
- GRB 260131A/B: EP/FXT X-ray afterglow detection
- Konus-Wind detection of GRB 260128A / EP260128a
- Konus-Wind detection of GRB 260131A/B
- GRB 260131A/B: GOTO candidate optical counterpart consistent with the MAXI localisation
- EP260131a: refined analysis of the EP-WXT and autonomous EP-FXT observations
- GRB 260131B: MAXI/GSC detection
- GRB 260127B: AstroSat CZTI detection
- GRB 260130A: Fermi GBM Detection
- EP260131a: Einstein Probe detection of an X-ray transient
- GRB 260127B: Fermi GBM Detection
- GRB 260130A: Fermi GBM Final Real-time Localization
- EP260128a: J band upper limit by SYSU 80cm infrared telescope
- GRB 260127A: Swift-BAT refined analysis
- GRB 260128B: SVOM detection of a burst through offline search
- IPN triangulation of GRB 260127B (short)
- GRB 260127A: INASAN-Kislovodsk, SAO RAS, and Terskol K-800 optical observations
- EP260128a: refined analysis of the EP-WXT and autonomous EP-FXT observations
- EP260128a: Einstein Probe detection of an X-ray transient
- Fermi GRB 260127A: Global MASTER-Net observations report
- GRB 260127A: Swift-XRT refined Analysis
- GRB 260127B: GOTO candidate optical counterpart
- Fermi GRB 260127B: Global MASTER-Net observations report
- GRB 260127B: Fermi GBM Final Real-time Localization
- GRB 260127A: Swift detection of a burst
- EP260126a: Optical upper limit with Kinder observations
- EP260126a: Einstein Probe detection of a fast X-ray transient
- Fermi-LAT Gamma-ray Observations of IceCube-260125A
- Konus-Wind detection of GRB 260120B
- GRB 260120A: AstroSat CZTI detection
- GRB 260122B: Swift-BAT refined analysis
- GRB 260120B: AstroSat CZTI detection
- EP260119a: Assy AZT-20 optical observations
- EP260119a: Mondy and SAO RAS optical upper limits
- Fermi GRB 260120C: Global MASTER-Net observations report
- GRB 260120B: Swift-XRT refined Analysis
- GRB 260120B: Fermi GBM Observation
- SVOM GRB260121.06: Global MASTER-Net observations report
- GRB 260120C: Fermi GBM Final Real-time Localization
- GRB 260101A: 239Alferov CubeSat detection
- EP260116a: COLIBRÍ observations of a tentative optical rebrightening
- Swift GRB260120B: Global MASTER-Net observations report
- GRB 260120B: Fermi GBM Final Real-time Localization
- Fermi trigger No 790601190: Global MASTER-Net observations report
- Fermi trigger No 790570272: Global MASTER-Net observations report
- GRB 260120A: Fermi GBM Final Real-time Localization
- EP260119a: update of EP-FXT follow-up observation
- SVOM GRB260119.90: Global MASTER-Net observations report
- EP260116a: COLIBRÍ detection of a fading optical source
- EP260119a: Global MASTER-Net observations report
- GRB 260117A: ZTSh optical upper limit
- EP260119a: COLIBRÍ optical counterpart candidate
- EP260119a: preliminary result from the EP-FXT observation
- GRB 260110A: SVOM detection of a burst through offline search
- EP260119a: EP-WXT detection of a fast X-ray transient
- Swift GRB260118.48: Global MASTER-Net observations report
- Fermi-LAT Gamma-ray Observations of IceCube-260115A