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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"

7294 results found.

  1. GRB001204: Optical observations
  2. GRB001120: Gunn-i observations
  3. GRB001120: Optical observations
  4. GRB 001109: deep JHK upper limits
  5. GRB001007: Optical observations
  6. GRB001007, Radio observations
  7. GRB 001007, BVR-band observations
  8. GRB000911: VLT infrared observation
  9. GRB000911: optical VLT observations
  10. GRB000926 K'-band Observation
  11. J and K band observations of GRB 000926
  12. GRB000911 Optical Observations
  13. GRB 000926, optical observation by Oksanen (vsnet-grb)
  14. GRB000926: Optical observations
  15. GRB 000926, Optical Observation
  16. GRB000926, radio observations
  17. GRB 000926: Optical candidate
  18. Optical candidate for GRB000926
  19. GRB000911: Corrected coordinates
  20. GRB000911: Optical Transient
  21. GRB000911, Radio and Optical observations
  22. GRB000911: Optical observations
  23. GRB000830: Optical observations
  24. Chandra Position of GRB000210
  25. GRB000830: Optical observations
  26. HST/STIS observations of the host galaxy of GRB 980329
  27. GRB000630, Optical Observations
  28. GRB000630, optical observations
  29. GRB000630, optical observations
  30. GRB000630: Optical observations
  31. possible optical counterpart of GRB 000630
  32. GRB000604 - Optical observations
  33. GRB000604, optical observations
  34. X-ray Afterglow of GRB 000529
  35. GRB000529: Optical Observations
  36. GRB000519: Optical observations
  37. GRB 000528 Optical Observations
  38. GRB 000418, Optical observation
  39. GRB 000418, Optical Observation
  40. GRB 000418, optical observation
  41. GRB 000418, Optical Observation
  42. GRB 000418, Optical Observation
  43. GRB 000408, optical observations
  44. GRB000301C - R magnitude lower limit
  45. GRB 000307 optical observations
  46. GRB000301C - B and R photometry
  47. GRB000301C - R photometry
  48. GRB 000301c: K' observations
  49. GRB000301C, optical R-band observations
  50. GRB000301c - R photometry and nearby faint source confirmation
  51. GRB 000301c: K' observations
  52. GRB 000301C: K' Observations
  53. GRB000301C OT candidate optical observations
  54. GRB000301C - Host galaxy not detected in R (?)
  55. GRB000301C optical observations
  56. GRB 000301c near-IR observations
  57. GRB000301C, optical observations
  58. GRB000301C, near-infrared observations (JHK' photometry)
  59. GRB 000301C: OT confirmed
  60. GRB000301c optical observations
  61. GRB000301C, optical observations
  62. GRB 000301C : Optical Candidate
  63. GRB000214: X-ray afterglow candidate
  64. Optical candidate for GRB000210
  65. GRB 000115 Optical observations
  66. GRB 991216: J band spectrophotometry
  67. GRB 991208 Keck Spectroscopy
  68. GRB 991208 optical observations
  69. GRB 991208: Radio Observations
  70. GRB991106: BeppoSAX/BATSE results
  71. GRB 990510: optical observations
  72. GRB 990510: optical observations
  73. GRB981220 VLBA observations
  74. GRB 990316, Radio observations
  75. GRB 990316, Optical observations
  76. GRB990316, Optical observations
  77. GRB 990316 optical observations
  78. GRB 981220, radio observations
  79. GRB990123, Optical observation
  80. GRB990123 Optical Observation
  81. GRB 981226 Optical Observations
  82. GRB981226 Optical Observations
  83. GRB 981226 optical observations
  84. GRB980425 Optical Follow-up
  85. GRB 980703 H-band Observations
  86. SGR1900+14 field optical observations
  87. Reduced error box of SGR 1627-41
  88. GRB980613 Near Infra-Red Observations
  89. GRB980519 Optical Observations
  90. GRB980515, BeppoSAX IAUC to be submitted
  91. GRB 980425 Radio Light Curve
  92. GRB 980425 Brightness Temperature
  93. GRB980425: Radio Observations
  94. GRB 971214: KPNO Optical Observations

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