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.
Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
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"14 results found.
- GRB 150120A: 9.8 GHz VLA upper limit
- GRB 150120A: Gemini-N imaging and host redshift
- GRB 150120A: possible AMI 15 GHz detection
- GRB 150120A: ISON-NM early optical limit
- GRB 150120A: Swift-XRT refined Analysis
- GRB 150120A: KAIT Optical Upper Limit
- GRB 150120A: Swift-BAT refined analysis
- GRB 150120A: Swift/UVOT Upper Limits
- GRB 150120A: Fermi GBM observation
- GRB 150120A: Enhanced Swift-XRT position
- GRB 150120A: Gemini-North optical imaging
- GRB 150120A: P60 optical observations
- GRB 150120A: Prompt enhanced Swift-XRT position
- GRB 150120A: Swift detection of a possibly-short burst