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"
6094 results found.
- GRB 221022B: Fermi GBM detection
- GRB 221021A: Fermi GBM observation
- GRB 221017A: Swift-XRT observations
- GRB 221009A: Second epoch of NuSTAR data
- GRB 221016A: Swift-XRT refined Analysis
- GRB 221016A: Fermi GBM observation
- GRB 221009A: Armchair Energetics
- GRB 221009A: Fermi LAT data rate effects due to extremely high flux
- MAXI/GSC refined analysis of the bright X-ray afterglow of GRB 221009A/Swift J1913.1+1946
- GRB 221009A: IXPE preliminary upper limits of X-ray polarization
- GRB 221009A: Gamma-ray Detection by SIRI-2
- GRB 221006A: Swift-XRT afterglow detection
- GRB221009A: optical afterglow measurements from Konkoly Observatory
- GRB 221009A: NuSTAR Detection
- GRB221009A: INTEGRAL detection of Hard X-ray emission up to 38 hours after trigger
- GRB 221009A: Upper limits from HAWC 8 hours after trigger
- GRB 221009A (Swift J1913.1+1946): iTelescope optical observation
- GRB 221009A: Continued Swift/XRT observations
- Konus-Wind detection of GRB 221009A
- GRB 221009A (Swift J1913.1+1946): Burke-Gaffney Observatory optical observations
- GRB 221009A: Fermi-LAT refined analysis
- GRB 221009A: Swift-XRT refined Analysis
- GRB 221009A or Swift J1913.1+1946: Fermi-LAT detection
- GRB 221008A: Swift-XRT observations
- GRB 221006A: Swift-XRT observations
- GRB 220930A: Swift-XRT refined Analysis
- Fermi-LAT gamma-ray observations of IceCube-220928A
- GRB 220924A: Fermi GBM detection
- GRB 220921A: Fermi GBM detection
- GRB 220921A: Swift-XRT Observations
- GRB 220921A: Fermi-LAT detection
- Fermi-LAT gamma-ray observations of IceCube-220918A and detection of a new gamma-ray source, Fermi J0502.5+0037
- IceCube-220907A: No significant detection in HAWC
- GRB 220909A: Fermi GBM observation
- GRB 220910A: Fermi GBM observation
- GRB 220909A: Swift-XRT observations
- GRB 220831A: Gemini-South Infrared Observations
- GRB 220907A: Fermi GBM observation
- GRB 220907A: Swift-XRT refined Analysis
- Fermi-LAT Gamma-ray Observations of IceCube-220907A
- GRB 220907A: Swift-XRT position
- GRB 220831A: Swift-UVOT Upper Limits
- GRB 220831A: Fermi GBM observation
- GRB 220831A: Swift-XRT observations
- IceCube-220822A: No significant detection in HAWC
- GRB 220826A: Fermi GBM observation
- GRB 220826A: Swift-XRT refined Analysis
- GRB 220825A: Fermi GBM observation
- GRB 220826A: iTelescope optical afterglow observations
- GRB 220823A: Fermi GBM detection
- Fermi-LAT gamma-ray observations of IceCube-220822A and detection of a new gamma-ray source, Fermi J1810.1+2154
- Konus-Wind detection of GRB 220813A
- GRB 220810A: Further Swift-XRT observations
- GRB 220813A: Swift-XRT refined Analysis
- GRB 220810A: Swift-XRT observations
- GRB 220730A: Fermi GBM detection
- GRB 220730A: Swift-XRT afterglow detection
- GRB 220730A: Swift-XRT observations
- GRB 220715B: Fermi GBM detection
- GRB 220715B: Swift-XRT refined Analysis
- GRB 220714B: Fermi GBM observation
- GRB 220715A: AGILE/MCAL detection
- GRB 220714B: Swift-XRT refined Analysis
- GRB 220711B: 10.4 m GTC(+EMIR) observations
- GRB 220711B: 10.4 m GTC(+EMIR) observations
- GRB 220710A: Swift-XRT afterglow detection
- GRB 220711B: NUTTelA-TAO / BSTI Early Optical Limits (Preliminary)
- GRB 220711B: GIT optical upper limits
- GRB 220711B: Swift-XRT refined Analysis
- GRB 220708B: GIT optical upper limits
- GRB 220708A: Swift-XRT refined Analysis
- GRB 220708B: Swift-XRT afterglow detection
- GRB 220706A: Swift-XRT refined Analysis
- Alert from the HAWC Burst Monitor HAWC-220702A
- GRB 220701A: Swift-XRT refined Analysis
- Fermi-LAT Gamma-ray Observations of IceCube-220629A
- Fermi-LAT Gamma-ray Observations of IceCube-220627A
- IceCube-220629A: No significant detection in HAWC
- IceCube-220627A: No significant detection in HAWC
- GRB 220627A: Swift-XRT afterglow detection
- Konus-Wind detection of GRB 220627A
- Swift XRT observations of WISEA J145820.77+412101.9 / IceCube 220624A
- Fermi-LAT Gamma-ray Observations of IceCube-220624A and and detection of a new gamma-ray source, Fermi J1458.0+4119
- GRB 220627A: Fermi-LAT detection
- IceCube-220624A: No significant detection in HAWC
- GRB 220623A: GIT optical upper limits.
- GRB 220611A: X-ray afterglow Chandra sub-arcsecond localization
- GRB 220623A: Swift-XRT refined Analysis
- GRB 220623A: iTelescope optical upper limit
- GRB 220618A: Fermi GBM detection
- GRB 220611A: Continued Gemini Infrared Observations
- GRB 220617A: Fermi GBM observation
- GRB 220618A: Swift-XRT refined Analysis
- GRB 220617A: Swift-XRT observations
- GRB 220617A: Fermi-LAT detection
- GRB 220611A: Gemini Ks counterpart detection
- GRB 220611A: Gemini South Infrared Detection
- GRB 220611A: Swift-XRT refined Analysis
- GRB 220606A: Fermi GBM observation
- GRB 220606B: Fermi GBM Observation