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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').

10039 results found.

  1. GRB 990316, Optical observations
  2. GRB990217: BeppoSAX/GRBM data
  3. Optical Observations of GRB990217
  4. GRB 990123: Discovery of the Probable Host Galaxy
  5. GRB 990123: New Constraints on Possible Foreground Galaxies
  6. GRB990123, Optical BVRI Observations
  7. GRB990123, ASCA X-ray observation of afterglow
  8. GRB 990123 Spectroscopic Redshifts
  9. GRB 990123 Optical Follow-Up
  10. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  11. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  12. GRB981220, Correction to GCN 179
  13. GRB981220 B, R and I band observations
  14. GRB 981220 optical R and I observations
  15. GRB 981226 - Infrared Observations
  16. GRB 981226 optical observations
  17. BeppoSAX NFI Observation of GRB980425
  18. GRB980425 Optical Follow-up
  19. GRB980703: LOTIS observation at early times
  20. GRB 980703
  21. GRB980703
  22. GRB980703 optical followup
  23. SGR1627-41, BeppoSAX-GRBM detections
  24. GRB980613, BeppoSAX WFC positions
  25. GRB980519, BeppoSAX-WFC updated position
  26. GRB980519, BeppoSAX-WFC position
  27. BSAX Observations of GRB980425 field
  28. GRB 980425 optical observations
  29. GRB 980425 optical observations
  30. GRB 980425 optical observations
  31. GRB980329 optical observations
  32. GRB971214: Keck R & I-band Observations
  33. Optical Observations of the GRB 971227 field
  34. Optical Observations on GRB 971227
  35. GRB971227: Plaskett R-band observations
  36. GRB 971227: Optical clarifications
  37. GRB971227: LOTIS observations
  38. GRB 971214: KPNO Optical Observations
  39. Optical Observations of GRB 971214 at Keck

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