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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"

45442 results found.

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

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