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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"

42605 results found.

  1. GRB010214, candidate optical afterglow
  2. GRB010214, optical observations
  3. BeppoSAX GRB010220: refined position
  4. BeppoSAX ALERT: GRB010220
  5. GRB010214: BeppoSAX WFC and GRBM preliminary data
  6. GRB 010214: X-Ray afterglow
  7. GRB 010214, Optical Observations
  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 possible OA in 2MASS
  54. GRB 001212 possible OA
  55. IPN triangulation of GRB001212
  56. GRB001204: Optical observations
  57. GRB001204, Radio observations
  58. IPN triangulation of GRB001204 (short/hard)
  59. GRB 001105, further optical observations
  60. GRB001120: Gunn-i observations
  61. GRB001120: Optical observations
  62. GRB001109, optical observations
  63. GRB001120, optical observations
  64. WSRT 4.8 GHz observations of GRB001109
  65. IPN triangulation of GRB001120
  66. Optical/NIR observations of GRB001109
  67. GRB 001109: deep JHK upper limits
  68. GRB 001109 X-ray afterglow with BeppoSAX
  69. CORRECTION to XMM-Newton observation of GRB001025
  70. GRB001109: Optical observations
  71. GRB001109: BeppoSAX/NFI Observations
  72. GRB001109, R-band optical observations
  73. GRB001109, Radio observations
  74. GRB001109: BeppoSAX refined WFC position
  75. BeppoSAX ALERT: GRB001109
  76. GRB001105 BVRI field photometry correction
  77. GRB001105, BVRI field photometry
  78. GRB 001105, R-band observation
  79. IPN TRIANGULATION OF GRB001105
  80. GRB 001025B, Optical obervations
  81. GRB 991208: HST Imaging of the Host Galaxy
  82. GRB000926: R-image of the host galaxy
  83. GRB 001025B, I-band observations
  84. XMM-Newton observation of GRB001025
  85. GRB001025B, Radio observations
  86. GRB 001025 Optical Observations
  87. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  88. CORRECTION TO IPN/RXTE ERROR BOX FOR GRB001025
  89. IPN triangulation of GRB001025
  90. GRB001007: Optical observations
  91. ASM Localization of GRB 001025
  92. GRB001007, Radio observations
  93. IPN TRIANGULATION OF GRB001020
  94. GRB001019, Optical Observations
  95. GRB 001018, Possible Radio Afterglow
  96. GRB001018, Gamma Ray Observations
  97. IPN TRIANGULATION OF GRB001019
  98. IPN TRIANGULATION OF GRB001018
  99. IPN TRIANGULATION OF GRB 001017
  100. GRB 000926: Improved Absorber Redshift

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