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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"

21577 results found.

  1. GRB010214 follow-up from Hanle
  2. GRB 010222: Near-IR Observations
  3. GRB 010222: Optical Observations
  4. GRB010222: Optical decay slope
  5. GRB 010214, Optical Observations
  6. GRB010222: Sub-millimeter detection
  7. GRB010222: R-band fading behavior
  8. GRB010222: Optical Observations
  9. GRB010222, radio observations
  10. GRB010222, optical observations
  11. GRB010222: BeppoSAX/NFI Observations
  12. GRB010214B,Gamma Ray Observations
  13. GRB010222
  14. GRB010220, Radio and Optical Observations
  15. GRB 010220, simultaneous optical observations
  16. GRB010214, candidate optical afterglow
  17. GRB010214, optical observations
  18. GRB 010214, Optical Observations
  19. GRB010213, Radio Observations
  20. GRB010213 Optical Observation
  21. GRB010213, Radio Observations
  22. J-Band Observation of GRB 010214.
  23. GRB010214, Radio Observations
  24. GRB010214, optical observations
  25. GRB010213, optical observations
  26. GRB010213, Near-IR observations
  27. Possible InfraRed Transient of GRB 010214.
  28. GRB010214 Optical Observation
  29. GRB010214: BeppoSAX/NFI Observations
  30. GRB010213 (HETE) TAROT observations
  31. GRB 010214, optical observations
  32. GRB010213 detected by HETE
  33. IPN Status Report
  34. IPN/RXTE TRIANGULATION OF GRB010126
  35. GRB010126, TNG R-band observations
  36. GRB010126 Optical Observations
  37. GRB010126 optical observations
  38. GRB010126: Optical observations
  39. IPN TRIANGULATION OF GRB010126
  40. IPN/RXTE TRIANGULATION OF GRB010126
  41. GRB 010119, optical observations
  42. GRB010119: Optical observations
  43. Optical Observations of GRB 001018 at Keck
  44. GRB010119, Radio observations
  45. IPN TRIANGULATION OF GRB010119 (SHORT/HARD)
  46. Optical observations of GRB 001018 with JCAM
  47. IPN TRIANGULATION OF GRB010115
  48. IPN TRIANGULATION OF GRB010109
  49. GRB010103, optical observations
  50. IPN triangulation of GRB010104
  51. IPN triangulation of GRB010103
  52. GRB 001204: Ks observations
  53. H band observation of GRB 001212
  54. IPN triangulation of GRB001219
  55. GRB 001212 possible OA in 2MASS
  56. GRB 001212 possible OA
  57. IPN triangulation of GRB001212
  58. GRB001204: Optical observations
  59. Confirmation of IPN position for GRB001204
  60. GRB001204, Radio observations
  61. IPN triangulation of GRB001204 (short/hard)
  62. GRB 001105, further optical observations
  63. GRB001120: Gunn-i observations
  64. GRB001120: Optical observations
  65. GRB001109, optical observations
  66. GRB001120, optical observations
  67. WSRT 4.8 GHz observations of GRB001109
  68. IPN triangulation of GRB001120
  69. Optical/NIR observations of GRB001109
  70. GRB 001109: deep JHK upper limits
  71. GRB001109: Optical observations
  72. GRB001109: BeppoSAX/NFI Observations
  73. GRB001109, R-band optical observations
  74. GRB001109, Radio observations
  75. IPN TRIANGULATION OF GRB001105
  76. GRB000926: R-image of the host galaxy
  77. GRB 001025B, I-band observations
  78. GRB001025B, Radio observations
  79. GRB 001025 Optical Observations
  80. IPN TRIANGULATION OF GRB001025B (SHORT/HARD)
  81. IPN triangulation of GRB001025
  82. GRB001007: Optical observations
  83. ASM Localization of GRB 001025
  84. GRB001007, Radio observations
  85. IPN TRIANGULATION OF GRB001020
  86. GRB001019, Optical Observations
  87. GRB 001018, Possible Radio Afterglow
  88. GRB001018, Gamma Ray Observations
  89. IPN TRIANGULATION OF GRB001019
  90. IPN TRIANGULATION OF GRB001018
  91. IPN TRIANGULATION OF GRB 001017
  92. V,R,I band observations of GRB000926
  93. The Likely Optical/Infrared Afterglow of GRB 001011
  94. GRB 001007, BVR-band observations
  95. GRB000926 - Amateur Optical Observations
  96. GRB001007: Optical observations
  97. IPN triangulation of GRB001007
  98. IPN triangulation of GRB001005
  99. IPN triangulation of GRB 001004
  100. GRB000926 - Optical observations

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