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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"

26233 results found.

  1. GRB 120119A: GRT detection of early afterglow
  2. GRB 111225A: optical observations
  3. GRB 120121A: Swift/UVOT Upper Limits
  4. GRB 120121A: Swift-XRT refined Analysis
  5. GRB 120121A: Swift-BAT refined analysis
  6. GRB 120121A: Swift detection of a burst
  7. GRB 120119A, Swift-BAT refined analysis
  8. GRB 120119A: TAROT La Silla observatory optical observations
  9. GRB 120119A: Swift/UVOT Observations
  10. GRB 120119A: Swift-XRT refined Analysis
  11. GRB 120119A: Fermi GBM observation
  12. GRB 120118B, Swift-BAT refined analysis
  13. Konus-Wind observation of GRB 120119A
  14. GRB 120118B: Swift-XRT refined Analysis
  15. GRB 120118B : Lulin Optical limit
  16. GRB 120119A: Gemini-S redshift
  17. GRB 120119A: GROND Detection of the Optical/NIR Afterglow
  18. GRB 120118B: Swift/UVOT Upper Limits
  19. GRB 120119A: Liverpool Telescope afterglow detection
  20. GRB 120119A: PAIRITEL NIR Detection
  21. GRB 120119A: Swift detection of a burst with an optical counterpart
  22. GRB 120118B: Faulkes Telescope South observations
  23. GRB 120118B: Swift detection of a burst
  24. GRB 120116A: Swift/UVOT Upper Limits
  25. GRB 120116A: Swift-XRT refined Analysis
  26. AXP 4U 1042+61: Mondy optical observations
  27. GRB 120116A: Mondy optical observations
  28. GRB 120116A: Gemini optical/IR candidate
  29. GRB 120116A: WHT optical observations
  30. GRB 120116A: Optical observations at Crni Vrh
  31. GRB 120116A: Swift-BAT refined analysis
  32. GRB 120116A: Bassano Bresciano Observatory optical observations
  33. GRB 120116A: Swift detection of a burst
  34. GRB 120114A found in ground analysis of BAT data
  35. AXP 4U 0142+61: Swift-BAT refined analysis (trigger 511611)
  36. Swift detection of an SGR burst from AXP 4U 0142+61
  37. GRB 120107A: Suzaku WAM observation of the prompt emission
  38. GRB 120107A: Fermi GBM observation
  39. Konus-Wind observation of GRB 120107A
  40. IPN Triangulation of GRB 120107A
  41. GBM trigger 347620337 (GRB 120107A?) : High-energy photon emission in Fermi/LAT data
  42. GRB 120106A: Swift/UVOT Upper Limits
  43. GRB 120106A: Bassano Bresciano Observatory optical observations
  44. GRB 120106A: MITSuME Okayama Ks-band upper limit
  45. GRB 120106A: MASTER Early OT marginally detection
  46. GRB 120106A: Swift-XRT refined Analysis
  47. INTEGRAL Weak trigger #6433: GRT Optical Observation
  48. GRB 120106A: Swift-BAT refined analysis
  49. GRB 120106A: TAROT Calern observatory optical observations
  50. GRB 120106A: Swift detection of a burst
  51. GRB 111222A: Fermi GBM observations
  52. GRB111225A: RAPTOR Early Detection of the Optical Counterpart
  53. GRB 120102A: Fermi GBM observation
  54. Konus-Wind observation of GRB 120102A
  55. GRB 120102A: Swift-BAT refined analysis
  56. GRB 120102A: Swift-XRT refined Analysis
  57. GRB 120102A: Swift/UVOT Detection
  58. GRB 120102A: Swift detection of a burst with an optical counterpart
  59. GRB 111228A, optical observations
  60. Konus-Wind observation of GRB 111228A
  61. GRB 111228A: correction for GCN 12787
  62. GRB 111228A: Optical and NIR observations with Kanata telescope
  63. GRB 111229A: Swift/UVOT Detection
  64. GRB 111229A: Faulkes Telescope South observations
  65. GRB 111229A: Swift-XRT refined Analysis
  66. GRB 111229A: Gemini-South Redshift
  67. GRB 111229A: Swift-BAT refined analysis
  68. GRB 111229A: Swift detection of a burst
  69. GRB 111228A: Liverpool Telescope Observations
  70. GRB 111225A: Lightbuckets Optical Observations
  71. GRB 111228A: P60 Observations
  72. GRB 111228A: T100 observations
  73. GRB 111228A: Swift-XRT refined Analysis
  74. FERMI GRB111228.45: MASTER observations
  75. GRB 111228A: Gemini South Redshift
  76. GRB 111228A: PAIRITEL NIR Detection
  77. GRB 111228A: TAROT La Silla observatory observations
  78. GRB 111228A: GRAS017 optical observations
  79. GRB 111228A: Swift/UVOT Detection
  80. GRB 111228A: NOT optical observation
  81. GRB 111228A, Swift-BAT refined analysis
  82. GRB 111228A: optical observations
  83. GRB 111228A: TAROT Calern observatory. OT decay stopped
  84. GRB 111228A: Fermi GBM observation
  85. GRB 111228A: TAROT Calern observatory. OT seems still bright
  86. GRB 111225A, optical observations
  87. GRB 111228A: Swift detection of a burst with an optical counterpart
  88. GRB 111225A: Swift/UVOT Observations
  89. GRB 111215A: Keck/LRIS Imaging
  90. GRB 111225A: Keck/LRIS Afterglow Photometry
  91. GRB 111222A : Suzaku WAM observation of the prompt emission
  92. GRB 111225A: PAIRITEL NIR Upper Limits
  93. GRB 111225A: GRT Optical Observation
  94. GRB 111225A: Swift-XRT refined Analysis
  95. GRB 111225A, Swift-BAT refined analysis
  96. GRB 111225A: Super-LOTIS early detection
  97. GRB 111225A: TAROT Calern observatory optical detection
  98. GRB 111225A: TAROT Calern observatory optical observations
  99. GRB 111225A: Swift detection of a burst with an optical counterpart
  100. GRB 111222A: Swift/UVOT Observations

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