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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"

27399 results found.

  1. GRB 051211B, optical observation
  2. GRB 051211A: Swift/UVOT upper limits
  3. GRB 051211B: Swift/UVOT upper limits
  4. GRB 051211A,optical observation
  5. GRB051211B: Liverpool Telescope observation
  6. GRB051211b: P60 Observations
  7. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  8. GRB 051210: Swift/UVOT upper limits
  9. GRB 051210: Magellan Imaging
  10. GRB 051211: TAROT optical limits
  11. GRB 051211B: a possible optical detection by TAROT
  12. GRB 051211:IAC80 optical observations
  13. GRB 051210: SALT detection limit
  14. GRB 051210: Swift XRT refined analysis
  15. GRB 051210: FRAM early limit
  16. GRB 051210: Swift-BAT refined analysis of a short burst
  17. GRB051210: Swift UVOT Observation
  18. GRB 051210: Swift detection of a burst
  19. An extraordinary long burst on December 3 from SGR1806-20
  20. Possible resuming of the SGR 1806-20 activity
  21. GRB051117B: Swift XRT refined analysis
  22. GRB051117b: No Swift/UVOT Detection
  23. GRB 051117A: Swift/UVOT Detection of an Afterglow: Correction
  24. GRB 051117A: Swift/UVOT Detection of an Afterglow
  25. GRB051111: Suzaku WAM observation of the prompt emission
  26. GRB051008: Suzaku WAM observation of the prompt emission
  27. GRB 051117B: R and I observations of possible host galaxy
  28. GRB 051117A: Refined analysis of the Swift-BAT burst
  29. GRB 051117B: Refined analysis of the Swift-BAT burst
  30. GRB 051117B,optical observation
  31. GRB 051117B: Lulin R and I band observation
  32. GRB051114: results of the Swift-XRT observation
  33. GRB 051109B : Nainital upper limits
  34. GRB 051114: Radio Observations
  35. GRB 051114: Swift-BAT refined analysis
  36. GRB050925: analysis of the XMM-Newton observation
  37. GRB 051114: Swift-BAT detection of a short burst
  38. GRB 051111: Further spectroscopic analysis
  39. GRB 051111: Radio afterglow
  40. GRB 051113: Swift-BAT refined analysis
  41. GRB051103: Radio Observations
  42. GRB/SGR 050925: XMM-Newton ToO observation
  43. GRB051111: Swift/UVOT Observations
  44. GRB051111: XRT preliminary analysis
  45. GRB 051111: Swift-BAT refined analysis
  46. GRB 051109A Optical Observations
  47. GRB 051111A : Lulin BVRI multi band afterglow observation
  48. GRB051111a: SARA Observations
  49. GRB 051111a: IR photometry
  50. GRB 051109B. Radio Observations
  51. GRB 051109A
  52. GRB051109A - radio observations
  53. GRB 051109B: Swift-BAT refined analysis
  54. GRB 051109A: Swift-UVOT Observations
  55. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  56. GRB051109B: no UVOT source detected
  57. GRB051109B: XRT refined analysis
  58. GRB 051109B : Lulin Optical Observations
  59. GRB 051109A : Lulin BVRI Optical afterglow observation
  60. GRB051109A: further steepening in the X-ray light curve
  61. GRB051109A: XRT refined analysis
  62. GRB 051109B: Super-LOTIS Observations
  63. GRB051105B: REM Optical observation
  64. GRB 051109B: Swift detection of a burst
  65. GRB 051109: Rc and Ic observations
  66. GRB 051109: Swift-BAT refined analysis
  67. GRB 051109a: IR Photometry and Astrometry
  68. GRB051109: Swift detection of a burst
  69. GRB 051109a: IR Detections
  70. GRB051105B: Swift/XRT upper limit
  71. GRB051105B: Swift/UVOT upper limit
  72. GRB051103: MASTER: OT limit and host galaxy candidates
  73. GRB051028: Swift-XRT refined analysis
  74. GRB 051105a, observation from Naini Tal and OSN
  75. GRB 051105a: MDM Observations
  76. GRB 051105A: TNG optical observations
  77. GRB051105A: Swift/UVOT Observations
  78. GRB 051105A, radio observations
  79. GRB051103:_MASTER_optical_observations
  80. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  81. GRB 051105A, optical observations
  82. XRT observations of GRB 051105A
  83. GRB 051105b: ART optical limits
  84. GRB 051105B (INTEGRAL 2701): Optical observation
  85. GRB 051105: Swift detection of a short burst
  86. Recent GRB UBVRcIc field photometry
  87. GRB051028 SARA Observation
  88. GRB051028: optical observations
  89. GRB051028: Swift/UVOT upper limits
  90. GRB051028: Swift XRT Position
  91. GRB051028:MASTER observations
  92. GRB051021B: Swift/UVOT Upper limits
  93. GRB 051021, Optical Observations
  94. GRB 051022: XRT Refined Spectral and Temporal Analysis
  95. GRB051012: Swift-XRT analysis
  96. GRB051021B: Swift XRT refined analysis
  97. GRB 051022, mm counterpart
  98. GRB 051022: Swift/UVOT Upper Limits
  99. GRB051022: Radio Counterpart
  100. GRB051022: IR observations

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