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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"

27549 results found.

  1. GRB981220 B, R and I band observations
  2. Optical Observations of GRB981226
  3. GRB 981220
  4. GRB 981220, radio observations
  5. GRB 980326/Host Galaxy
  6. GRB980425 Optical Follow-up
  7. GRB980703 Very Long Baseline Interferometry
  8. Optical Observations of the Host Galaxy of GRB 980519
  9. GRB980703 - BeppoSAX/GRBM detection
  10. GRB980703: Radio transient
  11. GRB 980703: Spectrum of the proposed optical counterpart
  12. RXTE Observation of GRB 980706
  13. GRB980703: LOTIS observation at early times
  14. GRB980613 Optical Observations
  15. GRB 980703 H-band Observations
  16. GRB980703 optical followup
  17. GRB 980613: Detection of the probable host galaxy
  18. GRB 980613 Optical Observations
  19. GRB 980613 optical observations
  20. GRB980613 Optical Observations
  21. GRB980613 BeppoSAX-NFI follow up
  22. GRB 980519 Optical Observations
  23. GRB 980519
  24. GRB980519 optical observations
  25. GRB980519 optical observations
  26. GRB980519 optical observations
  27. GRB980515, BeppoSAX IAUC to be submitted
  28. BSAX Observations of GRB980425 field
  29. SAX J0840.7+2248 Optical Observations
  30. GRB 980329 ROSAT observation
  31. GRB980326 X-ray Observations
  32. GRB980326, optical observations
  33. GRB980329, Fading IR counterpart to radio source
  34. GRB980329
  35. GRB980329 Keck K-band observations
  36. GRB980329 sub-millimeter observations
  37. GRB980329 near-IR observations
  38. GRB980329 optical observations
  39. GRB980329 optical observations
  40. GRB980329 VLA observations
  41. GRB980329 optical observations
  42. Near-IR follow-up on GRB 971227
  43. Optical Observations of the GRB 971227 field
  44. GRB971227: Plaskett R-band observations
  45. GRB 971227: Optical clarifications
  46. GRB971227: Further CAHA R-band images
  47. GRB 971227: CAHA R-band images
  48. GRB 971214: Redshift from Keck Optical Observations
  49. GRB 971214: KPNO Optical Observations

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