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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"

20494 results found.

  1. IPN TRIANGULATION OF GRB010324
  2. GRB990705, VLT-FORS1 observations of the host galaxy
  3. GRB 010222 - HEGRA GeV/TeV Observations
  4. GRB010222: Sub-millimeter vanishing act
  5. GRB 010222, Optical Observations
  6. Sub-millimeter Excess/GRB 010222
  7. GRB 010222
  8. GRB 010222 HST/Chandra TOO
  9. GRB010222 further R-band photometry
  10. GRB010222 Optical observations
  11. GRB010222, field photometry
  12. GRB010222 further R-band photometry
  13. GRB010222, possible increase of optical decay slope
  14. GRB 010222 BV optical observations
  15. GRB010220, Optical Observations
  16. GRB010222 R-BAND OBSERVATION
  17. GRB 010220: Near-IR Observations
  18. GRB010214 follow-up from Hanle
  19. GRB 010222: Near-IR Observations
  20. GRB 010222: Optical Observations
  21. GRB010222: Optical decay slope
  22. GRB 010214, Optical Observations
  23. GRB010222: Sub-millimeter detection
  24. GRB010222: R-band fading behavior
  25. GRB010222: Optical Observations
  26. GRB010222, radio observations
  27. GRB010222, optical observations
  28. GRB010222: BeppoSAX/NFI Observations
  29. GRB010214B,Gamma Ray Observations
  30. GRB010222
  31. GRB010220, Radio and Optical Observations
  32. GRB 010220, simultaneous optical observations
  33. GRB010214, candidate optical afterglow
  34. GRB010214, optical observations
  35. GRB 010214, Optical Observations
  36. GRB010213, Radio Observations
  37. GRB010213 Optical Observation
  38. GRB010213, Radio Observations
  39. J-Band Observation of GRB 010214.
  40. GRB010214, Radio Observations
  41. GRB010214, optical observations
  42. GRB010213, optical observations
  43. GRB010213, Near-IR observations
  44. Possible InfraRed Transient of GRB 010214.
  45. GRB010214 Optical Observation
  46. GRB010214: BeppoSAX/NFI Observations
  47. GRB010213 (HETE) TAROT observations
  48. GRB 010214, optical observations
  49. GRB010213 detected by HETE
  50. HETE Status
  51. GRB010126, TNG R-band observations
  52. GRB010126 Optical Observations
  53. GRB010126 optical observations
  54. GRB010126: Optical observations
  55. GRB 010119, optical observations
  56. GRB010119: Optical observations
  57. Optical Observations of GRB 001018 at Keck
  58. GRB010119, Radio observations
  59. Optical observations of GRB 001018 with JCAM
  60. GRB010103, optical observations
  61. GRB 001204: Ks observations
  62. H band observation of GRB 001212
  63. GRB 001212 possible OA
  64. GRB001204: Optical observations
  65. GRB001204, Radio observations
  66. GRB 001105, further optical observations
  67. GRB001120: Gunn-i observations
  68. GRB001120: Optical observations
  69. GRB001109, optical observations
  70. GRB001120, optical observations
  71. WSRT 4.8 GHz observations of GRB001109
  72. Optical/NIR observations of GRB001109
  73. GRB 001109: deep JHK upper limits
  74. GRB001109: Optical observations
  75. GRB001109: BeppoSAX/NFI Observations
  76. GRB001109, R-band optical observations
  77. GRB001109, Radio observations
  78. GRB 001025B, I-band observations
  79. GRB001025B, Radio observations
  80. GRB 001025 Optical Observations
  81. GRB001007: Optical observations
  82. GRB001007, Radio observations
  83. GRB001019, Optical Observations
  84. GRB 001018, Possible Radio Afterglow
  85. GRB001018, Gamma Ray Observations
  86. V,R,I band observations of GRB000926
  87. The Likely Optical/Infrared Afterglow of GRB 001011
  88. GRB 001007, BVR-band observations
  89. GRB000926 - Amateur Optical Observations
  90. GRB001007: Optical observations
  91. GRB000926 - Optical observations
  92. GRB000926 - Optical observations
  93. GRB000926 - Optical observations
  94. GRB000926 - Optical observations
  95. GRB 000926: optical observations
  96. GRB 000926, Optical Observations
  97. GRB000926 - Optical observations
  98. GRB000911: optical VLT observations
  99. GRB000926 optical observations
  100. GRB000926 - Optical observations

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