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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').
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"

21 results found.

  1. GRB 240905E: further NOT optical observations
  2. GRB 240905E: SVOM/VT optical observations
  3. GRB 240905E: SVOM/VT optical observations (duplicate submission of GCN 37453)
  4. GRB 240905E: GIT optical upper limit
  5. GRB 240905E: Gaoyazi/GOT optical upper limits
  6. GRB 240905E: NUTTelA-TAO / BSTI Optical Limits
  7. GRB 240905E: J-band observations with WINTER
  8. GRB 240905E: CrAO Optical Afterglow observations, possible OT candidate
  9. GRB 240905E: AKO Optical Upper Limit
  10. GRB 240905E: SVOM/C-GFT optical upper limit
  11. GRB 240905E: OHP/MISTRAL T193 optical upper limit
  12. GRB 240905E: NOT optical upper limits
  13. GRB 240905E: REM optical/NIR upper limits
  14. GRB 240905E: Swift-XRT refined Analysis
  15. GRB 240905E: SVOM/GRM observation
  16. GRB 240905E: LCOGT Optical Upper Limit
  17. GRB 240905E: Swift/UVOT Upper Limits
  18. GRB 240905E: SAO RAS optical upper limit
  19. GRB 240905E: Nanshan/HMT optical upper limit
  20. Swift GRB 240905E: Global MASTER-Net observations report
  21. GRB 240905E: Swift detection of a burst

Advanced

Download all Circulars as a .tar.gz archive:
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