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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"

3050 results found.

  1. GRB 111208A: Swift XRT/UVOT observations
  2. GRB 111205A: Swift XRT Observations
  3. GRB 111204A: TNG NIR observations
  4. GRB 111204A: Swift-XRT refined Analysis
  5. GRB 111204A: Swift/UVOT Upper Limits
  6. GRB 111201A: Confirmation of the X-ray afterglow
  7. GRB111201A: Swift-XRT observations
  8. GRB 111129A: Swift-XRT refined Analysis
  9. GRB 111123A: Swift-XRT refined Analysis
  10. GRB 111121A: Swift-XRT refined Analysis
  11. GRB 111117A: Swift-XRT refined Analysis
  12. GRB 111109A: Swift-XRT refined Analysis
  13. GRB 111107A: Swift-XRT refined Analysis
  14. GRB 111103B : WIYN 3.5m NIR observations
  15. GRB 111103B: Swift-XRT refined Analysis
  16. GRB 111029A: Swift-XRT refined Analysis
  17. GRB 111029A: PAIRITEL NIR Upper Limits
  18. GRB 111022B: Swift-XRT refined Analysis
  19. GRB 111022A: Swift-XRT refined Analysis
  20. GRB 111020A: Swift-XRT refined Analysis
  21. GRB 111018A: Swift-XRT refined Analysis
  22. GRB111016A : WIYN 3.5m NIR observations
  23. GRB 111016A: Swift-XRT refined Analysis
  24. GRB 111008A : miniTAO/ANIR NIR observations
  25. GRB 111008A: Swift-XRT refined Analysis
  26. GRB 111005A : miniTAO/ANIR NIR observations
  27. GRB 111005A: GROND NIR observations
  28. GRB 110928A: Swift-XRT refined Analysis
  29. GRB 110928A: Further PAIRITEL NIR Observations
  30. GRB 110928A: PAIRITEL NIR Observations
  31. GRB 110921A: Swift-XRT refined Analysis
  32. GRB 110918A: Swift-XRT refined Analysis
  33. GRB 110915B : X-ray afterglow confirmation
  34. GRB 110918A: Swift/UVOT Detection of the Optical Counterpart
  35. GRB 110918A: Swift-XRT observations
  36. GRB 110915A: Swift/UVOT Upper Limits
  37. GRB 110915A: GROND Upper limits
  38. GRB 110915A: Swift-XRT refined Analysis
  39. GRB 110915A: Deep Near-IR Limits from Magellan
  40. GRB 110915B: XRT afterglow candidate
  41. GRB 110903A: Swift/UVOT Upper Limits
  42. GRB 110903A: Swift-XRT observations
  43. Trigger 502024: Swift detection of KS 1741-293
  44. GRB110825A: Swift target of opportunity observation
  45. Swift-BAT Trigger 501485 is noise
  46. Swift J1834.9-0846: Precise X-ray Position and the Confirmation of its Spin Period
  47. GRB 110820A: Swift-XRT refined Analysis
  48. GRB 110818A: Swift-XRT refined Analysis
  49. GRB 110815A: Swift-XRT and UVOT refined Analysis
  50. RXTE Discovery of the Spin Period of Swift J1834.9-0846
  51. GRB 110808A: Swift-XRT refined Analysis
  52. GRB 110726A: Swift-XRT refined Analysis
  53. GRB 110801A: Swift-XRT refined Analysis
  54. GRB 110731A: Swift-XRT refined Analysis
  55. GRB 110721A: Swift observations of afterglow candidate
  56. GRB 110719A: Swift-XRT refined Analysis
  57. Swift J1822.3-1606
  58. GRB 110715A: Swift-XRT refined Analysis
  59. Swift trigger 457076 is not a GRB
  60. GRB 110709B: Swift-XRT refined Analysis
  61. GRB 110709A: Swift-XRT refined Analysis
  62. GRB 110708A: Swift/XRT afterglow candidate for the INTEGRAL burst
  63. GRB 110625A: Swift-XRT refined Analysis
  64. Swift J185003.2-005627: Swift-XRT/UVOT refined analysis
  65. GRB 110604A: final update on Swift-XRT observations
  66. GRB 110610A: Swift-XRT refined Analysis
  67. Swift detection of the X-ray afterglow of GRB 110604A
  68. GRB 110530A: Swift-XRT refined Analysis
  69. GRB 110521A: Swift-XRT refined analysis
  70. GRB 110520A: Swift-XRT refined Analysis
  71. GRB 110503A: Swift-XRT refined Analysis
  72. GRB 110503A: PAIRITEL NIR Detection
  73. GRB 110426A: Swift/XRT non-detection
  74. GRB 110428A : X-ray afterglow confirmation
  75. GRB 110428A : Swift-XRT observations
  76. GRB 110422A: Swift-XRT refined Analysis
  77. GRB 110420B: Swift-XRT afterglow candidate
  78. GRB 110420A: Swift-XRT refined Analysis
  79. GRB 110414A: Swift-XRT refined Analysis
  80. GRB 110411A: PAIRITEL NIR Upper Limits
  81. GRB 110411A: Swift-XRT refined Analysis
  82. GRB 110407A: Swift-XRT refined Analysis
  83. GRB 110328/Swift J164449.3+573451: Chandra observations
  84. GRB 110402A: Swift-XRT refined Analysis
  85. GRB 110402A: PAIRITEL NIR Upper Limits
  86. GRB 110328/Swift J164449.3+573451: Fermi observations
  87. GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Detection in 2nd Epoch
  88. GRB 110328A / Swift J164449.3+573451: PAIRITEL NIR Upper Limits
  89. GRB 110319B Swift-XRT afterglow confirmation
  90. GRB 110319B: Swift-XRT afterglow candidate.
  91. GRB 110319A: Swift-XRT refined Analysis
  92. GRB 110318B: Swift-XRT refined Analysis
  93. GRB 110315A: Swift-XRT refined Analysis
  94. GRB 110312A: Swift-XRT refined Analysis
  95. GRB 110305A: Swift-XRT refined Analysis
  96. GRB 110223A: Swift-XRT refined Analysis
  97. GRB 110223B: Swift-XRT refined Analysis
  98. GRB 110223B: Swift-BAT refined analysis
  99. GRB110213B: X-ray afterglow confirmation
  100. Swift XRT and UVOT Observations of OT 110215

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