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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"

6186 results found.

  1. GRB 090904A: Enhanced Swift XRT position
  2. GRB090902B: Swift XRT refined analysis
  3. GRB 090902B: Fermi LAT and GBM refined analysis.
  4. GRB 090902B: Enhanced Swift-XRT position
  5. GRB 090902B: Fermi LAT detection
  6. Swift Trigger 361477, called GRB090831B, is probably not real.
  7. GRB 090831C: Swift XRT Refined Analysis
  8. GRB 090827: Swift XRT and UVOT observations
  9. GRB 090823: Swift XRT possible detection of the X-ray afterglow
  10. GRB 090817: No host galaxy, no supernova
  11. GRB 090817: Swift/UVOT Observations of a Host Galaxy Candidate
  12. GRB 090817: Confirmation of the X-ray afterglow
  13. GRB 090815C: Swift refined analysis
  14. GRB 090817: Swift-XRT observations
  15. GRB 090814B: Confirmation of the X-ray afterglow
  16. GRB 090814B: I-band observations from 1.23m CAHA telescope
  17. GRB 090814B: Swift/UVOT Upper Limits
  18. GRB 090814B: Swift-XRT detection of a possible afterglow.
  19. GRB 090814A: Swift-XRT Team Refined Analysis
  20. GRB 090813: Swift-XRT refined analysis
  21. GRB090813: Swift/UVOT upper limits
  22. GRB 090812: Swift XRT refined analysis
  23. GRB 090621B: MAGIC telescope GeV observation
  24. GRB 090621A: MAGIC telescope GeV observation
  25. GRB 090809: WHT observations
  26. GRB 090809: Swift-XRT refined analysis
  27. GRB 090807: Swift-XRT refined analysis
  28. GRB 090728: Swift XRT refined analysis
  29. GRB 090727: Swift-XRT refined analysis
  30. GRB 090715B: Late-time Lick 3m observations
  31. GRB 090726: Swift-XRT Team refined analysis
  32. GRB 090726: optical transient candidate
  33. GRB 090715B: Lick observations
  34. GRB 090715B: break in the optical afterglow decay
  35. GRB 090715B: Swift XRT Refined Analysis
  36. GRB 090709A: deep optical observation with the 10.4m GTC
  37. GRB 090709A: Swift XRT Refined Analysis
  38. GRB 090709A - PAIRITEL Discovery of a Red Afterglow
  39. GRB 090709: PAIRITEL NIR Upper Limits
  40. Possible GRB090705: Swift-XRT observations
  41. GRB 090705: PAIRITEL NIR Observations
  42. XRF 090702: Swift-XRT refined analysis
  43. GRB 090628: Swift XRT refined analysis
  44. Fermi LAT observations of GRB 090626
  45. GRB 090625B: Swift-XRT refined analysis
  46. PAIRITEL observations of GRB 090618
  47. GRB 090621B: Swift-XRT refined analysis
  48. GRB 090621: Swift-XRT Team refined analysis
  49. GRB090618: Swift-XRT team refined analysis
  50. Swift XRT observations of GRB 090531A
  51. RXTE Discovery of Pulsations from SGR 0418+5729
  52. GRB 090607: XRT Team Refined Analysis
  53. GRB090530: Swift XRT refined analysis
  54. GRB 090529: Swift-XRT refined analysis
  55. GRB 090530: PAIRITEL NIR Detections
  56. GRB 090529: TLS Afterglow Observations
  57. GRB 090423: Fermi GBM T90 follow-up analysis results
  58. GRB 090516: Fermi GBM observation
  59. GRB 090519: Swift-XRT refined analysis
  60. GRB 090518: Swift-XRT refined analysis
  61. GRB 090516: Swift XRT refined analysis
  62. GRB 090515: Swift-XRT refined analysis
  63. GRB 090515: Gemini-N upper limit
  64. GRB 090510: Swift/UVOT host galaxy candidates
  65. GRB 090510: Fermi-LAT follow-up analysis
  66. GRB 090509, further Swift-BAT refined analysis
  67. GRB 090510: Swift XRT refined analysis
  68. Fermi LAT detection of GRB 090510
  69. GRB 090429A: Swift-XRT refined analysis
  70. GRB 090429B: Swift XRT refined analysis
  71. GRB 090426: Near infrared observation with ISLE at OAO
  72. GRB 090426: Swift-XRT refined analysis
  73. GRB 090424: Swift-XRT refined analysis
  74. GRB 090423: Near infrared observation at Okayama Observatory
  75. GRB 090423: Swift-XRT refined analysis
  76. GRB090418A Rc-band photometry
  77. GRB 090422: Swift-XRT refined analysis
  78. GRB 090417B: Optical observation
  79. GRB 090419: Swift-XRT refined analysis
  80. GRB 090418: Swift XRT refined analysis
  81. GRB 090417B: Swift-XRT refined analysis
  82. GRB 090418: PAIRITEL NIR detection
  83. GRB 090417B: Subaru NIR Observations
  84. GRB 090407: Swift-XRT refined analysis
  85. GRB 090404: Swift-XRT Team refined analysis
  86. GRB 090401B: NOT optical observations
  87. GRB 090328: Fermi-LAT refined analysis
  88. GRB 090401B: Swift XRT Refined Analysis
  89. GRB 090328B: MASTER-Irkutsk prompt optical short burst observations
  90. GRB 090328: Swift XRT refined analysis
  91. Fermi LAT and GBM detections of GRB090328
  92. GRB 090323: UVOT Detection of Afterglow
  93. GRB 090323: Swift-XRT refined analysis
  94. Konus-Wind observation of GRB 090323
  95. GRB 090323: GROND Detection of the Afterglow and Photo-z
  96. Fermi GBM and LAT detections of GRB 090323
  97. GRB 090313: VLT spectroscopy
  98. GRB 090313: Light curve steepening
  99. GRB 090313 - PAIRITEL NIR detections
  100. GRB 090313 optical observations

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