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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"

45446 results found.

  1. GRB010220: BeppoSAX WFC and GRBM preliminary data
  2. GRB010214, candidate optical afterglow
  3. GRB010214, optical observations
  4. BeppoSAX GRB010220: refined position
  5. BeppoSAX ALERT: GRB010220
  6. GRB010214: BeppoSAX WFC and GRBM preliminary data
  7. GRB 010214: X-Ray afterglow
  8. GRB 010214, Optical Observations
  9. GRB 010214 optical observation
  10. GRB010213, Radio Observations
  11. GRB010213 Optical Observation
  12. GRB010213, Radio Observations
  13. J-Band Observation of GRB 010214.
  14. GRB010214, Radio Observations
  15. GRB010214, optical observations
  16. GRB010213, optical observations
  17. GRB010213, Near-IR observations
  18. Possible InfraRed Transient of GRB 010214.
  19. GRB010214 Optical Observation
  20. GRB010214: BeppoSAX/NFI Observations
  21. GRB010213 (HETE) TAROT observations
  22. GRB 010214, optical observations
  23. GRB010213 detected by HETE
  24. GRB010214 refined WFC position
  25. BeppoSAX ALERT: GRB010214
  26. IPN Status Report
  27. HETE Status
  28. GRB010126 opt. obs.
  29. IPN/RXTE TRIANGULATION OF GRB010126
  30. GRB010126: CONCAM crude optical limits during GRB
  31. GRB010126, TNG R-band observations
  32. GRB010126 Optical Observations
  33. GRB010126 optical observations
  34. GRB010126: Optical observations
  35. IPN TRIANGULATION OF GRB010126
  36. IPN/RXTE TRIANGULATION OF GRB010126
  37. GRB 010119, optical observations
  38. GRB010119: Optical observations
  39. Optical Observations of GRB 001018 at Keck
  40. GRB010119, Radio observations
  41. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  42. Optical observations of GRB 001018 with JCAM
  43. IPN TRIANGULATION OF GRB010115
  44. IPN TRIANGULATION OF GRB010109
  45. IPN TRIANGULATION OF GRB010109
  46. GRB010103, optical observations
  47. IPN triangulation of GRB010104
  48. IPN triangulation of GRB010103
  49. GRB 001204: Ks observations
  50. H band observation of GRB 001212
  51. GRB & BeppoSAX: ground operations restored back to 24 hrs a day
  52. IPN triangulation of GRB001219
  53. GRB 001212 Optical Observation
  54. GRB 001212 Optical Observation
  55. GRB 001212 optical observation
  56. GRB 001212 possible OA in 2MASS
  57. GRB 001212 possible OA
  58. IPN triangulation of GRB001212
  59. GRB001204: Optical observations
  60. Confirmation of IPN position for GRB001204
  61. GRB001204, Radio observations
  62. IPN triangulation of GRB001204 (short/hard)
  63. GRB 001105, further optical observations
  64. GRB001120: Gunn-i observations
  65. GRB001120: Optical observations
  66. GRB001109, optical observations
  67. GRB001120, optical observations
  68. WSRT 4.8 GHz observations of GRB001109
  69. IPN triangulation of GRB001120
  70. Optical/NIR observations of GRB001109
  71. GRB 001109: deep JHK upper limits
  72. GRB 001109 X-ray afterglow with BeppoSAX
  73. CORRECTION to XMM-Newton observation of GRB001025
  74. GRB001109: Optical observations
  75. GRB001109: BeppoSAX/NFI Observations
  76. GRB001109, R-band optical observations
  77. GRB001109, Radio observations
  78. GRB001109: BeppoSAX refined WFC position
  79. BeppoSAX ALERT: GRB001109
  80. GRB001105, BVRI field photometry
  81. GRB 001105, R-band observation
  82. IPN TRIANGULATION OF GRB001105
  83. GRB 001025B, Optical obervations
  84. GRB 991208: HST Imaging of the Host Galaxy
  85. GRB000926: R-image of the host galaxy
  86. GRB 001025B, I-band observations
  87. XMM-Newton observation of GRB001025
  88. GRB001025B, Radio observations
  89. GRB 001025 Optical Observations
  90. GRB 001025A, optical observation
  91. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  92. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  93. IPN triangulation of GRB001025
  94. GRB001007: Optical observations
  95. ASM Localization of GRB 001025
  96. GRB001007, Radio observations
  97. IPN TRIANGULATION OF GRB001020
  98. GRB001019, Optical Observations
  99. GRB 001018, Possible Radio Afterglow
  100. GRB001018, Gamma Ray Observations

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