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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"

19611 results found.

  1. Trigger 331721 Due to Swift startracker loss-of-lock
  2. Detection of flare star Algol in Swift-BAT slew data
  3. Swift-BAT triggered on the flare star Algol
  4. GRB 081012: Fermi GBM detection
  5. GRB 081007 and GRB 081007B: Fermi GBM detection
  6. GRB 081012: Swift/UVOT analysis of initial observations
  7. GRB 081012: Swift/XRT detection
  8. GRB 081012, Swift-BAT refined analysis
  9. GRB 081012: ROTSE-III Optical Limits
  10. GRB 081012: Swift detection of a burst
  11. Revised table for GRB 081011 UVOT detections
  12. GRB081011: UVOT detection of an optical afterglow
  13. GRB 081011: Swift/XRT detection
  14. GRB 081011, Swift-BAT refined analysis
  15. GRB 081011: Swift detection of a burst
  16. GRB 081008, Swift-BAT refined analysis
  17. GRB 081008: Swift-XRT Refined Analysis
  18. GRB081008: Swift/UVOT observations
  19. GRB 081008: Enhanced Swift-XRT position
  20. GRB 081008: Swift detection of a burst with optical afterglow
  21. GRB 081008: ROTSE-III Detection of Optical Counterpart
  22. GRB081007: Swift/UVOT Observations
  23. GRB 081007, Swift-BAT refined analysis
  24. GRB 081007: Early RAPTOR measurements of optical counterpart
  25. GRB 081007: Swift-XRT Team refined analysis
  26. GRB 081007: Enhanced Swift-XRT position
  27. GRB 081007: Swift detection of a burst with optical afterglow
  28. AXP 1E 1547.0-5408: Swift/UVOT Upper Limits
  29. GRB 081003B: Swift-XRT upper limit
  30. GRB 081003A: OSN optical observations
  31. AXP 1E1547.0-5408: Swift-XRT Team refined analysis
  32. GRB 081003A: Swift-XRT Team position and analysis
  33. Swift-BAT refined analysis of AXP 1E1547.0-5408 (Trigger 330353)
  34. GRB 080928: Fermi GBM detection
  35. AXP 1E1547.0-5408 (SGR 1550-5418): Fermi GBM detection
  36. SGR 1550-5418 = AXP 1E1547.0-5408 (Trigger 330353)
  37. Swift discovery of a new Soft Gamma Repeater SGR 1550-5418
  38. Trigger 330353: Swift detection of a Galactic short soft burst
  39. GRB 081001: Observations from OSN
  40. GRB 081001: Swift UVOT Observations
  41. GRB 081001: Swift-XRT position
  42. GRB 080928: Watcher observations
  43. GRB 080928: VLT redshift
  44. GRB 080928: Swift-XRT refined analysis
  45. GRB 080928: Swift/UVOT observations
  46. GRB 080928, Swift-BAT final refined analysis
  47. GRB 080928: Enhanced Swift-XRT position
  48. GRB 080928, Swift-BAT initial refined analysis
  49. GRB 080928A: ROTSE-III Confirmation of Optical Counterpart
  50. GRB 080928: Swift detection of a burst with an optical counterpart
  51. Swift-BAT trigger 325707 is not a GRB
  52. Swift trigger 325707: Swift/UVOT Upper Limits
  53. Swift trigger 325707: Swift-XRT upper limit
  54. Swift detection of a possible GRB (trigger 325707)
  55. GRB080916A: Suzaku WAM observation of the prompt emission
  56. GRB 080922: Swift/UVOT Upper Limits
  57. GRB080922: Swift-XRT upper limit
  58. Trigger 324561: IGR J08408-4503 detected by Swift
  59. GRB 080919: Swift/UVOT Refined Analysis
  60. GRB 080919: Swift-XRT refined analysis
  61. GRB 080919, Swift-BAT refined analysis
  62. GRB 080919: Swift detection of a short burst
  63. GRB080913: Swift-BAT spectral lag
  64. SGR 0501+4516: preliminary results of the Suzaku ToO observation
  65. GRB 080916A: Fermi GBM detection
  66. GRB 080916C: Swift UVOT Refined Analysis
  67. GRB 080916C: Swift XRT refined analysis
  68. GRB 080916B: Swift-XRT refined analysis
  69. Konus-Wind observation of GRB 080916A
  70. GRB 080916C: GROND Detection of the Optical Afterglow Candidate
  71. GRB 080913: Konus-Wind and Swift/BAT joint spectral analysis
  72. GRB 080916C: Enhanced XRT position
  73. GRB 080916C: Swift/XRT detection of possible afterglow
  74. GRB 080916B: Swift UVOT Refined Analysis
  75. GRB 080916B, Swift-BAT refined analysis
  76. GRB080916A: Refined Swift/UVOT Observations
  77. GRB 080916B: Enhanced Swift-XRT position
  78. GRB 080916A: Swift XRT refined analysis
  79. GRB 080916A, Swift-BAT refined analysis
  80. GRB 080916B: Swift-XRT afterglow detection
  81. GRB 080916A: Enhanced Swift-XRT position
  82. GRB 080916B: Swift detection of a burst
  83. GRB 080916: Swift detection of a burst with optical afterglow
  84. GRB 080915B, Swift-BAT refined analysis
  85. GRB 080915B: Swift detection of a burst
  86. GRB 080915: Swift/UVOT Upper Limits
  87. GRB 080915: Swift-XRT afterglow detection and analysis
  88. GRB 080915, Swift-BAT refined analysis
  89. GRB 080915: ROTSE-III Optical Limits
  90. GRB 080915: Swift detection of a burst
  91. GRB 080913: Swift-XRT refined analysis
  92. GRB080913: Swift/UVOT Upper Limits
  93. GRB 080913: GROND photo-z
  94. GRB 080913, Swift-BAT refined analysis
  95. GRB 080913: VLT/FORS2 observations
  96. GRB 080913: Enhanced Swift-XRT position
  97. GRB 080913: GROND observation of a high-z optical/NIR afterglow candidate
  98. GRB 080913: Swift detection of a burst
  99. GRB 080906: Watcher observations
  100. Swift-BAT/-XRT refined analysis on trigger 324362 (LS I +61 303)

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