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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').

2445 results found.

  1. GRB 990506: Limits on the possible optical transient
  2. GRB 990506, armchair astronomy
  3. GRB 970228: Redshift and properties of the host galaxy
  4. GRB981220 VLBA observations
  5. GRB990321 REFINED IPN ANNULUS
  6. GRB990321 IPN TRIANGULATION
  7. GRB 990316 Optical Observations
  8. GRB990316: simultaneous optical observation
  9. ASM/IPN error box for GRB 990308 (BATSE #7457)
  10. GRB990308, Possible new SGR~0209+70
  11. GRB981220, IPN localization
  12. GRB 981220, radio observations
  13. GRB 990123: Updated Keck Spectroscopy Results
  14. GRB990123, Optical observation
  15. GRB 990123: New Constraints on Possible Foreground Galaxies
  16. Search for Potential Images of GRB 990123
  17. Search for Potential Images of GRB 990123
  18. GRB990123 IPN annulus
  19. GRB 990123 : Multiple and Distorted Images of the Host Galaxy?
  20. GRB 990123 Spectroscopic Redshifts
  21. GRB 990123: Possible Gravitationally Lensed Burst?
  22. GRB 990123 optical observations
  23. GRB 990123: Bright New Source, Possible Optical Transient
  24. Possible identification of SN1999E with GRB980910
  25. GRB981220
  26. GRB 981226 optical observations
  27. GRB 981220
  28. GRB980703: Radio transient
  29. SGR1627-41, Refined IPN annulus location
  30. Reduced error box of SGR 1627-41
  31. SGR 1627-41
  32. SGR1900+14
  33. SGR1900+14
  34. GRB980519 optical observations
  35. GRB980519 Optical Observations
  36. GRB 980425 Brightness Temperature
  37. GRB980329 infrared observations
  38. Untitled
  39. Untitled
  40. Untitled
  41. Untitled
  42. Untitled
  43. Untitled
  44. Possible new SGR from US Naval Observatory
  45. GRB 970828: Palomar Observations

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