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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

19663 results found.

  1. GRB 090516: Enhanced Swift-XRT position
  2. GRB 090516: Faulkes Telescope South optical afterglow
  3. GRB 090516: Swift detection of a burst
  4. GRB 090515: ROVOR Upper Limit
  5. GRB 090515: MMT/MMIRS NIR Upper Limit
  6. GRB 090515: Swift/UVOT Observations
  7. GRB 090515: Swift-XRT refined analysis
  8. GRB 090515: Enhanced Swift-XRT position
  9. GRB 090509: Fermi GBM observation
  10. GRB 090515: Swift-BAT refined spectral analysis
  11. GRB 090515: Swift-BAT refined analysis
  12. GRB 090509 - Zadko Telescope observations
  13. GRB 090515: Super-LOTIS Upper Limits
  14. GRB 090515: PAIRITEL Upper Limits
  15. GRB 090515: KAIT optical upper limits
  16. GRB 090515: ROTSE-III Optical Limits
  17. GRB 090515: Swift detection of a short burst
  18. GRB 090510: Suzaku WAM observation of the prompt emission
  19. GRB090510: VLT/FORS2 spectroscopic redshift
  20. GRB 090510: GROND observations
  21. GRB 090510: Swift/UVOT host galaxy candidates
  22. GRB 090510: Fermi-LAT follow-up analysis
  23. GRB 090509, further Swift-BAT refined analysis
  24. Konus-Wind observation of GRB 090510
  25. GRB 090510: UVOT refined analysis
  26. GRB 090510: Swift XRT refined analysis
  27. GRB 090510: Enhanced Swift-XRT position
  28. GRB 090510: NOT afterglow confirmation
  29. GRB 090510: Swift-BAT refined analysis
  30. GRB 090510: Fermi GBM detection
  31. GRB 090509: Swift-BAT refined analysis
  32. Fermi LAT detection of GRB 090510
  33. GRB 090510: Swift/UVOT Detection of a Candidate Optical Afterglow
  34. GRB 090510: Swift detection of a short hard burst
  35. GRB 090408: optical upper limit
  36. GRB 090418A: optical observation
  37. GRB 090509: GROND afterglow candidate
  38. GRB 090509: Swift detection of a burst
  39. GRB 090423: optical limit
  40. GRB 090424: optical observations
  41. GRB 090429A: ROVOR magnitude limit
  42. GRB 090426: optical observations
  43. GRB 090429D: Fermi GBM detection
  44. GRB 090429B: Swift/UVOT Upper Limits
  45. GRB 090429A: Swift/UVOT Upper Limits
  46. GRB 090429A: Swift-XRT refined analysis
  47. GRB 090429A: GROND upper limits
  48. GRB 090429B: Swift XRT refined analysis
  49. GRB 090429A: Enhanced Swift-XRT position
  50. GRB 090429B: RIMOTS optical upper limits
  51. GRB 090429B: Swift-BAT refined analysis
  52. GRB 090429A: Swift-BAT refined analysis
  53. GRB 090429B: Enhanced Swift-XRT position
  54. GRB 090429A - Correction to XRT position
  55. GRB090429B: Gemini-N infrared IR candidate
  56. GRB 090429B: GROND Observations
  57. GRB 090429B: Swift detection of a burst
  58. GRB 090429: Swift detection of a burst
  59. GRB 090424 : Multiband Optical observation from Nainital
  60. GRB 090423: CARMA mm observations
  61. GRB 090423: millimeter detection
  62. GRB 090426: Swift/BAT spectral lag results
  63. GRB 090424: Suzaku WAM observation of the prompt emission
  64. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  65. GRB090426 Swift/UVOT observations
  66. GRB 090426: Swift-BAT refined analysis
  67. GRB 090426: Swift-XRT refined analysis
  68. GRB 090423: GROND second epoch imaging and refined SED
  69. GRB 090426: Enhanced Swift-XRT position
  70. GRB 090426, RIMOTS optical upper limits
  71. GRB 090426: TNT confimation of optical counterpart
  72. GRB 090426: Swift detection of a burst with an optical counterpart
  73. GRB 090424: MASTER-Net prompt optical limit
  74. VLA radio observation of high-z GRB 090423
  75. GRB 090424: THO optical observations
  76. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  77. GRB 090423: Swift/BAT spectral lag results
  78. GRB 090424: Swift-XRT refined analysis
  79. GRB 090423: energetic, luminosity and jet break
  80. Swift/UVOT observations of GRB 090424
  81. GRB 090424: Enhanced Swift-XRT position
  82. GRB 090424: Swift-BAT refined analysis
  83. GRB 090424: Fermi GBM Observation
  84. GRB 090423: Fermi GBM observation
  85. GRB 090422: Fermi GBM observation
  86. GRB 090423: Ep,i - Eiso correlation
  87. GRB 090424: SDSS Galaxy at the Swift position
  88. GRB 090424: TNT optical observations
  89. GRB 090424: ROTSE-III Confimation of Optical Counterpart
  90. GRB 090424: Swift detection of a burst with an optical counterpart
  91. GRB 090423: GROND detection and preliminary photo-z
  92. GRB 090423: Swift-XRT refined analysis
  93. GRB090423 - Swift/UVOT upper limits.
  94. GRB 090423: NIR photometry and evidence for spectral break
  95. GRB 090422: Swift-XRT refined analysis
  96. GRB090423, RIMOTS optical upper limits
  97. GRB 090423: Enhanced Swift-XRT position
  98. GRB 090423: Swift-BAT refined analysis
  99. GRB 090422: Swift/UVOT Upper Limits
  100. GRB 090423: Faulkes Telescope South observations

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