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"15245 results found.
- GRB 260924A: COLIBRÍ optical observations
- GRB 260924A: Second-epoch J-band upper limit from the SYSU 80 cm infrared telescope
- EP260924a: EP-FXT follow-up observation
- Swift Trigger 1513439 is probably not a GRB
- Konus-Wind detection of GRB 260924A
- GRB 260924A: Extreme Isotropic-equivalent Gamma-ray Energy and encouragement for multiwavelength follow-up observations
- GRB 260924A: Optical follow-up observations with Kinder
- GRB 260924A: SVOM/GRM observation
- GRB 260923A: Insight-HXMT/HE detection
- EP260924a: EP-WXT detection of an X-ray transient
- GRB 260924A: J-band observations by the SYSU 80 cm infrared telescope
- GRB 260924A: GROWTH-India Telescope optical observations
- Konus-Wind detection of GRB 260922A
- Konus-Wind detection of GRB 260921A (correction to GCN 45722)
- GRB 260921A: SVOM/GRM observation
- GRB 260922A: COLIBRÍ Confirmation of the Optical Counterpart
- Konus-Wind detection of GRB 260921A (possible merger-origin)
- GRB 260924A: Fermi-LAT detection of a bright burst
- GRB 260924A: AstroSat CZTI detection
- GRB 260920A: SVOM/GRM observation
- GRB 260924A: NOT optical counterpart confirmation
- GRB 260922A: CALET Gamma-Ray Burst Monitor detection
- Trigger_21914: Swift ToO observations
- Fermi-LAT Gamma-ray Observations of IceCube-260919A
- Fermi-LAT Gamma-ray Observations of IceCube-260916A
- ATCA observations of GRB 260909A
- GRB 260922A: COLIBRÍ Optical Counterpart Candidate (correction to GCN 45698)
- GRB 260922A: COLIBRÍ optical upper limits
- Fermi-LAT Gamma-ray Observations of IceCube-260805A
- Konus-Wind detection of GRB 260810A
- GRB 260918A: SVOM/ECLAIRs refined analysis
- GRB 260917C: AstroSat CZTI detection
- GRB 260920B/EP260920b: GECAM-B detection of a burst
- GRB 260921A: AstroSat CZTI detection
- GRB 260921A: Fermi GBM Observation
- EP260920b: 2.2m CAHA optical afterglow detection and 10.4m GTC redshift confirmation
- GRB 260917B:: SVOM/ECLAIRs refined analysis
- The EP-WXT trigger 01709319528 is likely a flaring star
- EP260920a: VLT/HAWK-I near-infrared candidate
- GRB 260920A: AstroSat CZTI detection
- EP260920b: refined analysis of the EP-WXT and EP-FXT observations
- EP260920b: COLIBRÍ optical observations
- The EP-WXT trigger 01709318601 is likely a flaring star
- IceCube-260919A: Upper limits from a search for additional neutrino events in IceCube
- EP-WXT detected a brightening of HMXB LS V +44 17
- EP260920a: NOT optical upper limits
- EP260920a: refined analysis of the EP-WXT and autonomous EP-FXT observations
- EP260920a: COLIBRÍ optical upper limits
- EP260920a: Update of the LCO optical counterpart candidate
- EP260917a: refined analysis of the EP-FXT observations
- IceCube-260919A - IceCube observation of a high-energy neutrino candidate track-like event
- The EP-WXT trigger 01709318491 is likely a flaring star
- EP260806a: Yamaguchi Interferometer radio detections
- Konus-Wind detection of GRB 260916B (short/hard)
- GRB 260917B: Mondy optical upper limit
- EP260917b: EP-WXT detection of an X-ray transient
- EP260917A: J-band upper limit with WINTER
- GRB 260915A: Swift-XRT afterglow detection
- GRB 260918A: SVOM detection of a burst
- GRB 260917B: FRAM-Auger optical limits
- GRB 260916B: Fermi GBM Detection
- IceCube-260916A: Upper limits from a search for additional neutrino events in IceCube
- GRB 260917A: Glowbug gamma-ray detection
- GRB 260915A: SVOM/ECLAIRs refined analysis
- GRB 260917B: SVOM detection of a faint burst
- GRB 260914A: 2.2m CAHA optical afterglow detection and 10.4m GTC redshift confirmation
- The EP-WXT trigger 01709317235 is likely a flaring star
- IceCube-260916A - IceCube observation of a high-energy neutrino candidate track-like event
- GRB 260914A: SVOM/GRM observation
- GRB 260914A: Mondy and TShAO optical observations
- GRB 260914A: SVOM/ECLAIRs refined analysis
- GRB 260915A: Swift ToO observations
- GRB 260915A: J-band upper limit by SYSU 80cm infrared telescope
- GRB 260914A: REM optical/NIR observations
- GRB 260914A: VLT/X-shooter observations and redshift confirmation
- GRB 260915A: SVOM/VT optical upper limits
- GRB 260915A: SVOM/COLIBRÍ (FM-GFT) optical upper limit
- GRB 260915A: 10.4m GTC deep optical limits
- GRB 260915A: SVOM detection of a burst
- GRB 260914A: LCO optical observation
- GRB 260914A: SVOM/VT optical observation from VHF data
- GRB 260914A: SVOM detection of a burst
- GRB 260913A: SVOM detection of a faint burst
- GRB 260907A: SVOM/GRM observation
- GRB 260909A: SVOM/ECLAIRs refined analysis
- GRB 260910B: GOTO tentative optical counterpart candidates
- GRB 260909A: Swift ToO observations
- EP260806a: VLA+ALMA radio detections
- GRB 260909A: OHP/T193 z-band upper limit
- GRB 260909A: VLT optical and near-infrared upper limits
- GRB 260909A: SVOM/GRM observation
- GRB 260909A: SVOM detection of a burst
- GRB 260903A: Swift ToO observations
- GRB 260903A: SVOM/ECLAIRs refined analysis
- GRB260903A: Liverpool Telescope optical observations
- GRB 260830A: GECAM-B detection of a burst
- GRB 260830A: Insight-HXMT/HE detection
- GRB 260903A: OHP/T193 optical afterglow detection
- GRB 260903A: NOT optical observations and afterglow fading
- NuSTAR Transient 260828: SOAR Optical Upper Limits