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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"

5152 results found.

  1. IPN localization of GRB990907
  2. BeppoSAX MAIL n. 99/24: GRB ALERT: GRB990907
  3. GRB 990712, Optical Observation
  4. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  5. GRB 990712
  6. BeppoSAX: GRB990625
  7. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  8. GRB990506 observation plan
  9. Refined IPN error box for GRB990506
  10. GRB 990506, armchair astronomy
  11. ASM/IPN error box for GRB 990308 (BATSE #7457)
  12. GRB990308 (Trig. 7457), optical observations
  13. Optical Observations of GRB990217
  14. GRB990123 observations
  15. GRB 990123: Reduced HST Images
  16. GRB990123, is the "radio flare" due to an inhomogeneous medium?
  17. GRB 990123: New Constraints on Possible Foreground Galaxies
  18. GRB990123 Optical Observations
  19. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  20. GRB 990123: Continued Radio Observations
  21. Search for Potential Images of GRB 990123
  22. GRB990123, Optical BVRI Observations
  23. GRB 990123: near-infrared observations.
  24. GRB990123: NIR Observation
  25. "GRB 990123: New BV Observations"
  26. GRB990123 Optical Observations
  27. GRB981220
  28. GRB 981220 Optical observations
  29. GRB 981220 and GRB 981226, optical observations
  30. GRB 981226 optical observations
  31. GRB981220 B, R and I band observations
  32. GRB 981226 - Infrared Observations
  33. GRB 981220
  34. GRB981220 I-band Observations
  35. GRB980425 Optical Follow-up
  36. GRB980613 Optical Observations
  37. SGR 1627-41
  38. GRB980519 optical observations
  39. GRB 980519 Optical Observations
  40. GRB 980425 Brightness Temperature
  41. GRB980329, Fading IR counterpart to radio source
  42. Near-IR follow-up on GRB 971227
  43. GRB971214: Keck R & I-band Observations
  44. Optical Observations of the GRB 971227 field
  45. GRB971227: Plaskett R-band observations
  46. GRB971227: Further CAHA R-band images
  47. GRB 971214: KPNO Optical Observations
  48. Optical Observations of GRB 971214 at Keck
  49. GRB 971214: Optical Observations
  50. GRB 971024: Refined analysis by USNOFS Observations
  51. GRB 971024: USNO Observations
  52. GRB 970228: Keck/LRIS Optical Observations

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