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"24279 results found.
- GRB 260714B: COLIBRÍ optical counterpart candidate
- SVOM sb26071506: Global MASTER-Net observations report
- sb26071506: SVOM detection of a X-ray transient
- IceCube-260712A: No candidates with the Zwicky Transient Facility (ZTF)
- GRB 260715A: Fermi GBM Final Real-time Localization
- GRB 260714B: Fermi-LAT detection
- GRB 260714B: Fermi GBM Detection
- GRB 260714B: BALROG localization (Fermi Trigger 805746211 / GRB 260714766)
- IceCube-260712A: Upper limits from a search for additional neutrino events in IceCube
- GRB 260714B: Fermi GBM Final Real-time Localization
- GRB 260714A: Fermi GBM Final Real-time Localization
- GRB 260619A: SVOM/VT continuous optical observations
- GRB 260618B: SVOM/VT optical observations indicate shallow decay and reddening
- GRB 260708A: slowly decaying X-ray emission observed by EP/FXT
- EP260711a: EP-FXT follow-up observation
- GRB 260708A: GRANDMA Optical Observations
- Fermi-LAT Gamma-ray Observations of IceCube-260712A
- Fermi-LAT Gamma-ray Observations of IceCube-260708A
- Fermi-LAT Gamma-ray Observations of IceCube-260704A
- IceCube-260708A: Upper limits from a search for additional neutrino events in IceCube
- IceCube-260712A - IceCube observation of a high-energy neutrino candidate track-like event
- GRB 260708A: LCO optical observations
- GRB 260710A: Fermi GBM Detection
- GRB 260709A: SVOM/GRM detection
- GRB 260709A: GECAM-B observation
- The EP-WXT trigger 01709274666 is likely a new outburst of the CV SS Cyg
- IceCube-260708A: Observations with the Vera C. Rubin Observatory
- GRB 260710A: Fermi GBM Final Real-time Localization
- GRB 260704A: SVOM/ECLAIRs refined analysis
- IceCube-260708A: One candidate from the Zwicky Transient Facility
- GRB 260708A: Fermi-GBM observation
- IceCube Alert 260709A: Global MASTER-Net observations report
- GRB 260709A: Fermi GBM Final Real-time Localization
- IceCube-260708A - IceCube observation of a high-energy neutrino candidate track-like event
- LAT GRB260708.42: Global MASTER-Net observations report
- GRB 260708A: Fermi-LAT detection
- GRB 260705B: SVOM/GRM observation
- GRB 260708A: Fermi-GBM detection
- GRB 260706A: Further EP-FXT follow-up observation
- EP260707a is not a real source
- EP260707a: LCOGT Optical Upper Limit
- EP260707a: TRT optical upper limit
- GRB 260705A: Candidate Optical Counterpart from SOAR and Gemini-South and Possible Association with GRB 260705B
- GRB 260706A: SVOM/ECLAIRs refined analysis
- GRB 260706A: SVOM/GRM observation
- GRB 260706A: REM optical/NIR observations
- IceCube-260704A: No candidates from the Zwicky Transient Facility
- GRB 260706A: LCO optical upper limit
- GRB 260706A: EP-FXT follow-up observation
- GRB 260707A: Fermi GBM Final Real-time Localization
- The EP-WXT trigger 01709274141 is likely a flaring star
- GRB 260706A: Fermi GBM Observation
- IceCube-260704A: Upper limits from a search for additional neutrino events in IceCube
- IPN triangulation of GRB 260627A
- GRB 260705A: SVOM/ECLAIRs refined analysis
- GRB 260706A: SVOM detection of a burst
- GRB 260706A: Fermi GBM Final Real-time Localization
- The EP-WXT trigger 01709274014 is likely a flaring star
- GRB 260705A: LCO optical upper limits
- GRB 260704A: NOT optical upper limits
- GRB 260705C: Fermi GBM Final Localization
- GRB 260705B: Fermi GBM Final Real-time Localization
- Fermi GBM Sub-Threshold Detection of GRB 260705A
- GRB 260705A: SVOM detection of a burst
- GRB 260704A: EP-FXT follow-up observation
- GRB 260629A: SVOM/GRM observation of a short burst
- IceCube-260704A - IceCube observation of a high-energy neutrino candidate track-like event
- EP260703a: EP-FXT follow-up observation
- GRB 260704A: SVOM detection of a possible GRB
- GRB 260703B: Fermi GBM Final Localization
- EP260628b: EP-WXT detection of an X-ray transient and EP-FXT follow-up observation
- Fermi trigger No 804738310: Global MASTER-Net observations report
- Fermi GRB 260703A: Global MASTER-Net observations report
- GRB 260703A: Fermi GBM Final Localization
- GRB 260614B: ATCA Radio Upper Limits
- GRB 260610B / AT2026owq: SAO RAS, CrAO and INASAN further optical observations and light curve
- Fermi trigger No 804552016: Global MASTER-Net observations report
- GRB 260701A: Fermi GBM Final Real-time Localization
- Fermi-LAT Gamma-ray Observations of IceCube-260622A
- EP260628a: EP-FXT follow-up observation
- GRB 260629A: Fermi GBM Final Real-time Localization
- Fermi GRB 260628A: Global MASTER-Net observations report
- GRB 260628A: Fermi GBM Final Real-time Localization
- The EP-WXT trigger 01709272671 is likely a flaring star
- EP260626a: EP-FXT follow-up observation
- Konus-Wind detection of GRB 260623B / EP260623a
- EP260623a: TNG NIR afterglow detection
- GRB 260618A: Fermi GBM Observation
- GRB 260619A: SVOM/ECLAIRs refined analysis
- Konus-Wind detection of GRB 260618B
- GRB 260624A: Fermi GBM Final Real-time Localization (Duplicate Submission)
- GRB 260624A: Fermi GBM Final Real-time Localization
- EP260623a:refined analysis of the EP-WXT and EP-FXT observation
- IceCube-260622A: Upper limits from a search for additional neutrino events in IceCube
- IPN triangulation of GRB 260605A
- GRB 260623A: Fermi GBM Final Real-time Localization
- EP260623a: SVOM/VT optical observations
- EP260623a: REM optical/NIR afterglow detection
- GRB 260614B: EP-FXT follow-up observation
- IceCube-260622A - IceCube observation of a high-energy neutrino candidate track-like event