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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"

27031 results found.

  1. GRB 110208A: Swift-XRT refined Analysis
  2. GRB 110208A: Swift-BAT refined analysis
  3. GRB 110208A: Swift detection of a burst
  4. SGR-like outburst from the magnetar 1E 1841-04.5
  5. GRB 110207A: Fermi GBM observation
  6. GRB 110207A: TAROT Calern observatory optical observations
  7. GRB 110206A: GROND detection of afterglow candidate
  8. GRB 110207A: Swift-BAT refined analysis
  9. GRB 110206A: UVOT detection of afterglow candidate
  10. GRB 110207A: MASTER prompt and early optical observations
  11. Konus-Wind observation of GRB 110205A
  12. GRB 110207A: Swift detection of a burst
  13. GRB 110206A: Swift detection of a probable X-ray afterglow
  14. GRB 110206A: TAROT La Silla observatory optical observations
  15. GRB 110205A: Lightbuckets Optical Observations
  16. GRB 110205A: Swift/UVOT Continuing Observations
  17. Observations GRB 110205A
  18. GRB 110205A: Swift-BAT refined analysis
  19. GRB 110205A: Newcastle Observatory Optical Observations
  20. GRB 110205A: Swift-XRT refined Analysis
  21. GRB 110205A: PAIRITEL NIR Afterglow Detection
  22. GRB 110205A: TAROT Calern observatory detection of an optical flare
  23. GRB 110205A: ROTSE-III, Optical Counterpart is flaring to ~14 mag
  24. GRB 110205A: TAROT Calern observatory optical detection
  25. GRB 110205A: Swift detection of a burst with an optical candidate
  26. GRB 110128A: Fermi GBM detection
  27. GRB 110201A: Swift-XRT refined Analysis
  28. Swift/UVOT observations of GRB110201A
  29. GRB 110201A: Swift-BAT refined analysis
  30. GRB 110201A: Swift detection of a burst
  31. GRB 110125A: Fermi GBM detection
  32. GRB 110128A, Swift-BAT refined analysis
  33. GRB 110128A: Swift/UVOT observations
  34. GRB 110128A: Swift-XRT refined Analysis
  35. GRB 110120A: Suzaku WAM observation of the prompt emission
  36. GRB 110128A: TAROT Calern observatory upper limits
  37. GRB 110128A: Swift detection of a burst
  38. Konus-Wind observation of GRB 110120A
  39. GRB 110123A: Fermi GBM detection
  40. GRB 110120A: MASTER optical observations
  41. GRB 110120A: Fermi LAT detection
  42. IPN triangulation of GRB 110120A
  43. GRB 110119A: Fermi GBM detection
  44. GRB 110120A: Fermi GBM detection
  45. GRB 110119A: Suzaku WAM observation of the prompt emission
  46. GRB110119: Swift/UVOT Detection
  47. GRB 110119A: Swift-XRT refined Analysis
  48. GRB 110119A: Swift-BAT refined analysis
  49. GRB 110119A: PAIRITEL NIR Afterglow Detection
  50. GRB 110119A: Swift detection of a burst with an optical detection
  51. Swift-BAT trigger 442771 is a noise fluctuation
  52. GRB 101219B: Likely the GRB host emission dominates now in the uvw2 filter
  53. New feature in Fermi GBM GRB Ground Position Notices
  54. Swift-BAT Trigger 442539 is not a GRB
  55. Swift Trigger 442539 is probably not a GRB
  56. GRB101225A - timing analysis
  57. GRB 110112B: Fermi GBM observation
  58. The Christmas burst GRB 101225A - optical spectroscopy with GTC
  59. GRB 110112B: Swift XRT and UVOT observations of the INTEGRAL burst
  60. GRB 110112A: MITSuME Akeno and Okayama optical upper limits
  61. GRB 110112A: Swift-XRT refined Analysis
  62. GRB 110112A: Swift/UVOT upper limits
  63. GRB 110112A: Swift-BAT refined analysis
  64. GRB 110112A: Swift detection of a possible short burst
  65. GRB 110107A: Swift-XRT Afterglow Candidate
  66. GRB 110107A detected in ground analysis of BAT slew data
  67. GRB 110106B: Fermi GBM detection
  68. Short GRB 110106A: MASTER OT observations
  69. GRB 110106B: Swift-XRT refined Analysis
  70. GRB 110106B: Liverpool Telescope observations
  71. GRB 110106B: Swift-BAT refined analysis
  72. GRB 110106A: Swift/UVOT Upper Limits
  73. GRB 110106A: Swift-XRT refined Analysis
  74. GRB 110106A: Swift-BAT refined analysis
  75. GRB 110106B: Swift detection of a burst
  76. GRB 110106A: MASTER optical observations
  77. GRB 110106A: Swift detection of a burst
  78. GRB 101225A: Host galaxy
  79. GRB 110102A: Swift-XRT refined Analysis
  80. GRB 101219B: After 2 weeks still detected by Swift/UVOT
  81. Konus-Wind observation of GRB 110102A
  82. GRB110102A: Swift/UVOT observations
  83. GRB 110102A: Fermi GBM observation
  84. GRB 110102A: Swift-BAT refined analysis
  85. GRB 110102A: Swift detection of a burst with an optical detection
  86. GRB 101225A: optical break from NOT observation
  87. GRB 101225A: P60 Observations
  88. GRB 101225A: MAXI/GSC observations
  89. Tentative redshift of GRB101225A (Christmas's burst) from Swift-XRT data
  90. GRB 101225A, Swift-BAT refined analysis
  91. GRB 101225A: Swift/UVOT Detection
  92. GRB 101225A: Swift-XRT refined Analysis
  93. Trigger 441015 / GRB 101225A: Further NOT optical observation
  94. Trigger 441015 / GRB 101225A: NOT optical afterglow candidate
  95. GRB 101225A (Swift trigger 441015): optical upper limit
  96. Trigger 441015: Swift detection of a possible burst or transient
  97. GRB 101224A: NOT optical observation
  98. GRB 101224A: Swift/UVOT Upper Limits
  99. GRB 101224A: Fermi GBM observation
  100. GRB 101224A: Swift-XRT refined Analysis

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