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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"

3037 results found.

  1. GRB 090709A: Swift XRT Refined Analysis
  2. GRB 090709A - PAIRITEL Discovery of a Red Afterglow
  3. GRB 090709: PAIRITEL NIR Upper Limits
  4. Possible GRB090705: Swift-XRT observations
  5. GRB 090705: PAIRITEL NIR Observations
  6. XRF 090702: Swift-XRT refined analysis
  7. GRB 090628: Swift XRT refined analysis
  8. GRB 090625B: Swift-XRT refined analysis
  9. PAIRITEL observations of GRB 090618
  10. GRB 090621B: Swift-XRT refined analysis
  11. GRB 090621: Swift-XRT Team refined analysis
  12. GRB090618: Swift-XRT team refined analysis
  13. Swift XRT observations of GRB 090531A
  14. RXTE Discovery of Pulsations from SGR 0418+5729
  15. GRB 090607: XRT Team Refined Analysis
  16. GRB090530: Swift XRT refined analysis
  17. GRB 090529: Swift-XRT refined analysis
  18. GRB 090530: PAIRITEL NIR Detections
  19. GRB 090519: Swift-XRT refined analysis
  20. GRB 090518: Swift-XRT refined analysis
  21. GRB 090516: Swift XRT refined analysis
  22. GRB 090515: Swift-XRT refined analysis
  23. GRB 090510: Swift/UVOT host galaxy candidates
  24. GRB 090510: Swift XRT refined analysis
  25. GRB 090429A: Swift-XRT refined analysis
  26. GRB 090429B: Swift XRT refined analysis
  27. GRB 090426: Near infrared observation with ISLE at OAO
  28. GRB 090426: Swift-XRT refined analysis
  29. GRB 090424: Swift-XRT refined analysis
  30. GRB 090423: Near infrared observation at Okayama Observatory
  31. GRB 090423: Swift-XRT refined analysis
  32. GRB 090422: Swift-XRT refined analysis
  33. GRB 090419: Swift-XRT refined analysis
  34. GRB 090418: Swift XRT refined analysis
  35. GRB 090417B: Swift-XRT refined analysis
  36. GRB 090418: PAIRITEL NIR detection
  37. GRB 090417B: Subaru NIR Observations
  38. GRB 090407: Swift-XRT refined analysis
  39. GRB 090404: Swift-XRT Team refined analysis
  40. Swift/UVOT observations of GRB090401B
  41. Swift/UVOT observations of GRB090401B
  42. GRB 090401B: Swift XRT Refined Analysis
  43. GRB 090328: Swift XRT refined analysis
  44. GRB 090323: UVOT Detection of Afterglow
  45. GRB 090323: Swift-XRT refined analysis
  46. GRB 090323: GROND Detection of the Afterglow and Photo-z
  47. GRB 090313: Light curve steepening
  48. GRB 090313 - PAIRITEL NIR detections
  49. GRB 090313: Swift-XRT refined analysis
  50. GRB 090313: Faulkes Telescope North observations
  51. GRB 090306B: Confirmation of the X-ray afterglow
  52. GRB 090309: Swift-XRT refined analysis
  53. GRB 090308: Swift-XRT refined analysis
  54. GRB 090306B: Possible XRT afterglow
  55. GRB 090307: Swift-XRT afterglow confirmation and analysis
  56. GRB 090305: Swift-XRT refined analysis
  57. GRB 090205: Swift-XRT refined analysis
  58. GRB 090201: Swift-XRT refined analysis
  59. GRB 090201: Swift-XRT detection of the possible X-ray afterglow
  60. GRB 090126A: Swift/UVOT Upper Limits
  61. GRB 090126A: Swift-XRT Refined Analysis
  62. GRB 090123: Swift XRT refined analysis
  63. GRB 090118: Swift-XRT observations
  64. GRB090118 Swift/UVOT upper limits
  65. GRB090117 Swift/UVOT upper limits
  66. GRB090117: Swift-XRT detection of a possible candidate afterglow
  67. GRB 090113: Swift-XRT refined analysis
  68. GRB 090111: Swift-XRT refined analysis
  69. GRB 090107B: Swift XRT afterglow confirmation
  70. GRB 090107B: Swift-XRT detection of possible afterglow
  71. GRB 090102: Swift XRT refined analysis
  72. GRB081230: Swift-XRT refined analysis
  73. GRB 081228: Swift-XRT Team refined analysis
  74. GRB 081226B: Swift XRT and UVOT upper limits
  75. GRB 081226: Swift-XRT refined analysis
  76. GRB 081224: Swift-XRT observation
  77. GRB 081211B: Further Swift-XRT analysis
  78. Possible GRB 081211B: Swift/UVOT Upper Limits
  79. Possible GRB 081211B - Swift-XRT analysis
  80. GRB 081211: Swift XRT refined analysis
  81. GRB 081211: Swift/UVOT detection of an optical afterglow
  82. GRB 081210: Swift-XRT refined analysis
  83. GRB 081204: Swift XRT afterglow confirmation
  84. Swift-XRT observations of GRB 081203B
  85. GRB081203A: Swift-XRT refined analysis
  86. GRB 081203B: Swift-XRT candidate afterglow.
  87. GRB 081128: Swift-XRT refined analysis
  88. GRB 081127: Swift-XRT refined analysis
  89. GRB 081126: Swift-XRT refined analysis
  90. GRB 081121: Swift-XRT refined analysis
  91. GRB 081118: Swift-XRT refined analysis
  92. GRB 081109A: confirmation of possible detection host galaxy
  93. Further Swift-XRT observations of the probable GRB 081105.
  94. GRB 081025: Swift-XRT further analysis
  95. GRB 081024B: Swift-XRT late-time observations
  96. GRB 081109A: Swift-XRT refined analysis
  97. GRB 081028 - PAIRITEL NIR detection
  98. GRB 081104: refined XRT analysis
  99. GRB 081102: Swift-XRT refined analysis
  100. SGR 0623-0006 or GRB 081101: Swift-XRT refined analysis

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