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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

42260 results found.

  1. GRB 010222, Decay Slope Confirmed
  2. GRB010222: Another absorption line system
  3. GRB010222: Optical decay slope
  4. GRB 010214, Optical Observations
  5. GRB010222: Sub-millimeter detection
  6. GRB010222: R-band fading behavior
  7. GRB010222: Optical Observations
  8. GRB010222, radio observations
  9. GRB010222, optical observations
  10. GRB010222: BeppoSAX/NFI Observations
  11. Redshift of the Optical Transient of GRB010222
  12. GRB010222: possible optical counterpart
  13. GRB010222
  14. GRB010220, Radio and Optical Observations
  15. GRB 010220, simultaneous optical observations
  16. GRB010220: BeppoSAX WFC and GRBM preliminary data
  17. GRB010214, candidate optical afterglow
  18. GRB010214, optical observations
  19. GRB010214: BeppoSAX WFC and GRBM preliminary data
  20. GRB 010214: X-Ray afterglow
  21. GRB 010214, Optical Observations
  22. GRB 010214 optical observation
  23. GRB010213, Radio Observations
  24. GRB010213 Optical Observation
  25. GRB010213, Radio Observations
  26. J-Band Observation of GRB 010214.
  27. GRB010214, Radio Observations
  28. GRB010214, optical observations
  29. GRB010213, optical observations
  30. GRB010213, Near-IR observations
  31. Possible InfraRed Transient of GRB 010214.
  32. GRB010214 Optical Observation
  33. GRB010213 (HETE) TAROT observations
  34. GRB 010214, optical observations
  35. GRB010213 detected by HETE
  36. HETE Status
  37. GRB010126 opt. obs.
  38. IPN/RXTE TRIANGULATION OF GRB010126
  39. GRB010126: CONCAM crude optical limits during GRB
  40. GRB010126, TNG R-band observations
  41. GRB010126 Optical Observations
  42. GRB010126 optical observations
  43. GRB010126: Optical observations
  44. IPN/RXTE TRIANGULATION OF GRB010126
  45. GRB 010119, optical observations
  46. GRB010119: Optical observations
  47. Optical Observations of GRB 001018 at Keck
  48. GRB010119, Radio observations
  49. Optical observations of GRB 001018 with JCAM
  50. IPN TRIANGULATION OF GRB010109
  51. IPN TRIANGULATION OF GRB010109
  52. GRB010103, optical observations
  53. IPN triangulation of GRB010103
  54. GRB 001204: Ks observations
  55. H band observation of GRB 001212
  56. IPN triangulation of GRB001219
  57. GRB 001212 Optical Observation
  58. GRB 001212 Optical Observation
  59. GRB 001212 optical observation
  60. GRB 001212 possible OA in 2MASS
  61. GRB 001212 possible OA
  62. IPN triangulation of GRB001212
  63. GRB001204: Optical observations
  64. Confirmation of IPN position for GRB001204
  65. GRB001204, Radio observations
  66. IPN triangulation of GRB001204 (short/hard)
  67. GRB 001105, further optical observations
  68. GRB001120: Gunn-i observations
  69. GRB001120: Optical observations
  70. GRB001109, optical observations
  71. GRB001120, optical observations
  72. WSRT 4.8 GHz observations of GRB001109
  73. IPN triangulation of GRB001120
  74. Optical/NIR observations of GRB001109
  75. GRB 001109: deep JHK upper limits
  76. GRB 001109 X-ray afterglow with BeppoSAX
  77. GRB001109: Optical observations
  78. GRB001109: BeppoSAX/NFI Observations
  79. GRB001109, R-band optical observations
  80. GRB001109, Radio observations
  81. GRB001105, BVRI field photometry
  82. GRB 001105, R-band observation
  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. GRB001019, Optical Observations
  98. GRB 001018, Possible Radio Afterglow
  99. GRB001018, Gamma Ray Observations
  100. GRB 000926: Improved Absorber Redshift

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