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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"

30 results found.

  1. GRB 241025A: VIRT Optical Upper Limit
  2. GRB 241025A: VZLUSAT-2 detection
  3. GRB 241025A: radio detection with the VLA
  4. GRB 241025A: LBT optical observations
  5. GRB 241025A: The discovery of a BdHN I from data of Swift, Fermi, SVOM and Einstein Probe telescopes
  6. Konus-Wind detection of GRB 241025A
  7. GRB 241025A (EP241025a): Optical afterglow observations with the Tsinghua-Nanshan Optical Telescope
  8. GRB 241025A: further SAO RAS optical observations
  9. GRB 241025A: Swift/UVOT Detection
  10. GRB 241025A: SAO RAS optical observations
  11. GRB 241025A: Mondy optical observations
  12. GRB241025A: 1.3m DFOT optical afterglow detection
  13. ​GRB 241025A: optical photometry from Konkoly
  14. GRB 241025A: GROWTH-India Telescope optical observations
  15. GRB 241025A: COLIBRÍ Detection of the Afterglow
  16. GRB 241025A: Swift-XRT refined Analysis
  17. GRB 241025A: Fermi GBM Observation
  18. GRB 241025A: GRANDMA and Kilonova-Catcher optical afterglow detections and upperlimits
  19. Fermi GRB 241025A: Global MASTER-Net observations report
  20. Swift GRB 241025A: Global MASTER-Net observations report
  21. EP241025a (GRB 241025A): EP observations update
  22. GRB 241025A : SVOM/VT optical afterglow observations
  23. GRB 241025A: Enhanced Swift-XRT position
  24. GRB 241025A: NOT spectroscopic redshift of z = 4.20
  25. GRB 241025A: DDOTI Afterglow detection
  26. EP241025a (GRB 241025A): EP on-board trigger and autonomous follow-up observation
  27. GRB 241025A: SVOM/GRM observation
  28. GRB 241025A: TRT optical afterglow observation
  29. GRB 241025A: Fermi GBM Final Real-time Localization
  30. GRB 241025A: Swift detection of a burst with an optical counterpart

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