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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"

44978 results found.

  1. GRB010214 follow-up from Hanle
  2. GRB 010222: Near-IR Observations
  3. GRB 010222: Optical Observations
  4. GRB 010222, Decay Slope Confirmed
  5. GRB010222: Another absorption line system
  6. GRB010222: Optical decay slope
  7. GRB 010214, Optical Observations
  8. GRB010222: Sub-millimeter detection
  9. GRB010222: R-band fading behavior
  10. GRB010222: Optical Observations
  11. GRB010222, radio observations
  12. GRB010222, optical observations
  13. GRB010222: BeppoSAX/NFI Observations
  14. Redshift of the Optical Transient of GRB010222
  15. GRB010214B,Gamma Ray Observations
  16. GRB010222: possible optical counterpart
  17. GRB010222
  18. GRB010222
  19. GRB010222: BeppoSAX refined position
  20. ALERT: GRB010222: the brightest GRB observed by BeppoSAX
  21. GRB010220, Radio and Optical Observations
  22. GRB 010220, simultaneous optical observations
  23. GRB010220: BeppoSAX WFC and GRBM preliminary data
  24. GRB010214, candidate optical afterglow
  25. GRB010214, optical observations
  26. BeppoSAX GRB010220: refined position
  27. BeppoSAX ALERT: GRB010220
  28. GRB010214: BeppoSAX WFC and GRBM preliminary data
  29. GRB 010214: X-Ray afterglow
  30. GRB 010214, Optical Observations
  31. GRB 010214 optical observation
  32. GRB010213, Radio Observations
  33. GRB010213 Optical Observation
  34. GRB010213, Radio Observations
  35. J-Band Observation of GRB 010214.
  36. GRB010214, Radio Observations
  37. GRB010214, optical observations
  38. GRB010213, optical observations
  39. GRB010213, Near-IR observations
  40. Possible InfraRed Transient of GRB 010214.
  41. GRB010214 Optical Observation
  42. GRB010214: BeppoSAX/NFI Observations
  43. GRB010213 (HETE) TAROT observations
  44. GRB 010214, optical observations
  45. GRB010213 detected by HETE
  46. GRB010214 refined WFC position
  47. BeppoSAX ALERT: GRB010214
  48. IPN Status Report
  49. HETE Status
  50. GRB010126 opt. obs.
  51. IPN/RXTE TRIANGULATION OF GRB010126
  52. GRB010126: CONCAM crude optical limits during GRB
  53. GRB010126, TNG R-band observations
  54. GRB010126 Optical Observations
  55. GRB010126 optical observations
  56. GRB010126: Optical observations
  57. IPN TRIANGULATION OF GRB010126
  58. IPN/RXTE TRIANGULATION OF GRB010126
  59. GRB 010119, optical observations
  60. GRB010119: Optical observations
  61. Optical Observations of GRB 001018 at Keck
  62. GRB010119, Radio observations
  63. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  64. Optical observations of GRB 001018 with JCAM
  65. IPN TRIANGULATION OF GRB010115
  66. IPN TRIANGULATION OF GRB010109
  67. IPN TRIANGULATION OF GRB010109
  68. GRB010103, optical observations
  69. IPN triangulation of GRB010104
  70. IPN triangulation of GRB010103
  71. GRB 001204: Ks observations
  72. H band observation of GRB 001212
  73. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  74. IPN triangulation of GRB001219
  75. GRB 001212 Optical Observation
  76. GRB 001212 Optical Observation
  77. GRB 001212 optical observation
  78. GRB 001212 possible OA in 2MASS
  79. GRB 001212 possible OA
  80. IPN triangulation of GRB001212
  81. GRB001204: Optical observations
  82. Confirmation of IPN position for GRB001204
  83. GRB001204, Radio observations
  84. IPN triangulation of GRB001204 (short/hard)
  85. GRB 001105, further optical observations
  86. GRB001120: Gunn-i observations
  87. GRB001120: Optical observations
  88. GRB001109, optical observations
  89. GRB001120, optical observations
  90. WSRT 4.8 GHz observations of GRB001109
  91. IPN triangulation of GRB001120
  92. Optical/NIR observations of GRB001109
  93. GRB 001109: deep JHK upper limits
  94. GRB 001109 X-ray afterglow with BeppoSAX
  95. CORRECTION to XMM-Newton observation of GRB001025
  96. GRB001109: Optical observations
  97. GRB001109: BeppoSAX/NFI Observations
  98. GRB001109, R-band optical observations
  99. GRB001109, Radio observations
  100. GRB001109: BeppoSAX refined WFC position

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