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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"

6094 results found.

  1. GRB 060121: Swift/UVOT upper limits
  2. GRB 060121: Swift XRT refined analysis
  3. GRB 060121: Swift XRT refined position
  4. GRB060121: SARA Observations
  5. GRB 060121: Infrared Observations
  6. GRB 060116: possible I-J dropout
  7. GRB 060117: Refined analysis of the Swift-BAT burst
  8. GRB 060110: XRT position and analysis
  9. GRB 060115: Refined analysis of the Swift-BAT burst
  10. GRB 060114: Swift XRT upper limit
  11. GRB 060108: further analysis of VLT images
  12. GRB 060111B: Swift XRT refined analysis
  13. GRB060111 : XRT refined analysis
  14. GRB 060110: IR Candidate Afterglow
  15. GRB 060108: ISAS early observations and near IR upper limit
  16. GRB060108: P200 Ks Observations
  17. GRB 060105: ISAS observations and near IR upper limit
  18. GRB 060105: BAT refined analysis
  19. Swift-BAT trigger 175653 is not an astrophysical source
  20. GRB051227: SARA Observations
  21. GRB 051221B: Optical Observations with Kuiper 1.54m
  22. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  23. GRB051016: analysis of the XMM-Newton observation
  24. GRB 051221A: Chandra Afterglow Position
  25. GRB 051221B: Refined analysis of the Swift-BAT burst
  26. GRB 051221: Swift XRT refined analysis
  27. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  28. GRB051211A (=H3979): Refined Analysis
  29. GRB 051215: near-infrared observations
  30. GRB 051213: Swift-BAT refined analysis
  31. GRB 051211B: Swift XRT confirmation of the afterglow
  32. GRB 051211B: Swift XRT Observations
  33. GRB 051210: Swift XRT refined analysis
  34. GRB 051117b: NIR observations
  35. GRB051117A : XRT refined analysis
  36. GRB 051117B: Lulin R and I band observation
  37. GRB051114: results of the Swift-XRT observation
  38. GRB051111: XRT preliminary analysis
  39. GRB 051111: Swift-BAT refined analysis
  40. GRB 051111a: IR photometry
  41. GRB 051109B: Swift-BAT refined analysis
  42. GRB051109B: XRT refined analysis
  43. GRB051109A: XRT refined analysis
  44. GRB 051109a: IR Photometry and Astrometry
  45. GRB 051109a: IR Detections
  46. GRB051028: Swift-XRT refined analysis
  47. XRT observations of GRB 051105A
  48. GRB 051021, Optical Observations
  49. Chandra Observations of GRB 051022
  50. GRB051012: Swift-XRT analysis
  51. GRB 051022 Chandra Observations scheduled
  52. GRB 051022: SOAR JKs Observations
  53. GRB051021b: Magellan IR Imaging
  54. GRB 051022, J & K-band observation
  55. GRB 051021: P200 Ks Observations
  56. GRB051021: Swift XRT analysis
  57. GRB 051016b: Gemini Near IR Observations
  58. GRB 051016: Swift-BAT refined analysis
  59. GRB051008: Swift XRT refined analysis
  60. GRB051008: Refined analysis of the Swift-BAT burst
  61. GRB 051006: optical observations at Sierra Nevada
  62. GRB 051001, optical observations at Mt. John
  63. GRB 051001: AAT infra-red observations
  64. GRB 051001: Swift-BAT refined analysis
  65. GRB050925: Swift/XRT limits
  66. GRB/SGR 050925: IR Observations
  67. Refined analysis of the Swift-BAT soft short burst
  68. GRB 050922B: Correction to BAT refined analysis, longer burst
  69. GRB050922C: TNG spectroscopic observations
  70. GRB050922B: refined XRT analysis
  71. GRB050922C: Optical Observations
  72. GRB 050922C: NOT optical observations
  73. GRB050820B: analysis of the XMM-Newton observation
  74. GRB 050916: Swift-BAT refined analysis
  75. Swift-BAT trigger 155764 is not a GRB
  76. GRB050916 : Swift-XRT refined analysis
  77. GRB 050915B: Swift-BAT refined analysis
  78. GRB 050915: Swift-BAT refined analysis
  79. GRB050911: Upper limit on X-ray afterglow
  80. Swift-BAT trigger 155072 ground analysis
  81. GRB 050908: Swift-BAT refined analysis
  82. GRB 050908: Optical observations
  83. GRB 050906: Swift XRT upper limit
  84. GRB 050904: Keck I-band Imaging
  85. GRB 050904: early Swift XRT analysis results
  86. GRB050904: Optical Observations
  87. GRB 050827: Swift XRT preliminary analysis results
  88. GRB 050827: P200 NIR Observations
  89. GRB 050827: Swift-BAT refined analysis
  90. GRB050824: decay of the XRT light curve and updated X-ray spectrum
  91. GRB050822: Swift/UVOT upper limits
  92. GRB 050730, optical observation
  93. GRB050805b: CrAO optical limit
  94. GRB050805a : Null detection report
  95. GRB 050805b: OHP optical limits
  96. GRB 050730: OHP optical observations
  97. GRB 050802 : Lulin Optical follow-up observation
  98. GRB 050730: XRT refined analysis
  99. Swift/UVOT photometry of GRB050730
  100. GRB 050730, optical candidate

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