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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"

25995 results found.

  1. GRB051211B: Liverpool Telescope observation
  2. GRB051211b: P60 Observations
  3. GRB 051211A and GRB051211B: BOOTES simultaneous observations
  4. GRB 051210: Swift/UVOT upper limits
  5. GRB 051210: Magellan Imaging
  6. GRB 051211: TAROT optical limits
  7. GRB 051211B: a possible optical detection by TAROT
  8. GRB 051211:IAC80 optical observations
  9. GRB 051210: SALT detection limit
  10. GRB 051210: Swift XRT refined analysis
  11. GRB 051210: FRAM early limit
  12. GRB 051210: Swift-BAT refined analysis of a short burst
  13. GRB051210: Swift UVOT Observation
  14. GRB 051210: Swift detection of a burst
  15. An extraordinary long burst on December 3 from SGR1806-20
  16. Possible resuming of the SGR 1806-20 activity
  17. GRB051117B: Swift XRT refined analysis
  18. GRB051117b: No Swift/UVOT Detection
  19. GRB 051117A: Swift/UVOT Detection of an Afterglow: Correction
  20. GRB 051117A: Swift/UVOT Detection of an Afterglow
  21. GRB051111: Suzaku WAM observation of the prompt emission
  22. GRB051008: Suzaku WAM observation of the prompt emission
  23. GRB 051117B: R and I observations of possible host galaxy
  24. GRB 051117A: Refined analysis of the Swift-BAT burst
  25. GRB 051117B: Refined analysis of the Swift-BAT burst
  26. GRB 051117B,optical observation
  27. GRB 051117B: Lulin R and I band observation
  28. GRB051114: results of the Swift-XRT observation
  29. GRB 051109B : Nainital upper limits
  30. GRB 051114: Radio Observations
  31. GRB 051114: Swift-BAT refined analysis
  32. GRB050925: analysis of the XMM-Newton observation
  33. GRB 051114: Swift-BAT detection of a short burst
  34. GRB 051111: Further spectroscopic analysis
  35. GRB 051111: Radio afterglow
  36. GRB 051113: Swift-BAT refined analysis
  37. GRB051103: Radio Observations
  38. GRB/SGR 050925: XMM-Newton ToO observation
  39. GRB051111: Swift/UVOT Observations
  40. GRB051111: XRT preliminary analysis
  41. GRB 051111: Swift-BAT refined analysis
  42. GRB 051109A Optical Observations
  43. GRB 051111A : Lulin BVRI multi band afterglow observation
  44. GRB051111a: SARA Observations
  45. GRB 051111a: IR photometry
  46. GRB 051109B. Radio Observations
  47. GRB 051109A
  48. GRB051109A - radio observations
  49. GRB 051109B: Swift-BAT refined analysis
  50. GRB 051109A: Swift-UVOT Observations
  51. IPN triangulation and Konus spectrum of the short/soft GRB051107 (large
  52. GRB051109B: no UVOT source detected
  53. GRB051109B: XRT refined analysis
  54. GRB 051109B : Lulin Optical Observations
  55. GRB 051109A : Lulin BVRI Optical afterglow observation
  56. GRB051109A: further steepening in the X-ray light curve
  57. GRB051109A: XRT refined analysis
  58. GRB 051109B: Super-LOTIS Observations
  59. GRB051105B: REM Optical observation
  60. GRB 051109B: Swift detection of a burst
  61. GRB 051109: Rc and Ic observations
  62. GRB 051109: Swift-BAT refined analysis
  63. GRB 051109a: IR Photometry and Astrometry
  64. GRB051109: Swift detection of a burst
  65. GRB 051109a: IR Detections
  66. GRB051105B: Swift/XRT upper limit
  67. GRB051105B: Swift/UVOT upper limit
  68. GRB051103: MASTER: OT limit and host galaxy candidates
  69. GRB051028: Swift-XRT refined analysis
  70. GRB 051105a, observation from Naini Tal and OSN
  71. GRB 051105a: MDM Observations
  72. GRB 051105A: TNG optical observations
  73. GRB051105A: Swift/UVOT Observations
  74. GRB 051105A, radio observations
  75. GRB051103:_MASTER_optical_observations
  76. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  77. GRB 051105A, optical observations
  78. XRT observations of GRB 051105A
  79. GRB 051105b: ART optical limits
  80. GRB 051105B (INTEGRAL 2701): Optical observation
  81. GRB 051105: Swift detection of a short burst
  82. Recent GRB UBVRcIc field photometry
  83. GRB051028 SARA Observation
  84. GRB051028: optical observations
  85. GRB051028: Swift/UVOT upper limits
  86. GRB051028: Swift XRT Position
  87. GRB051028:MASTER observations
  88. GRB051021B: Swift/UVOT Upper limits
  89. GRB 051021, Optical Observations
  90. GRB 051022: XRT Refined Spectral and Temporal Analysis
  91. GRB051012: Swift-XRT analysis
  92. GRB051021B: Swift XRT refined analysis
  93. GRB 051022, mm counterpart
  94. GRB 051022: Swift/UVOT Upper Limits
  95. GRB051022: Radio Counterpart
  96. GRB051022: IR observations
  97. GRB051021A: Swift XRT refined analysis
  98. GRB051022: Optical Observations
  99. GRB051021b: Magellan IR Imaging
  100. GRB 051021, SMARTS optical/IR observations

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