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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

42568 results found.

  1. GRB 090117 - Fermi GBM Observations
  2. GRB 090117: GROND Upper Limits
  3. GRB090117 Swift/UVOT upper limits
  4. GRB090117: Swift-XRT detection of a possible candidate afterglow
  5. GRB 090117 - SuperAGILE Localization of a long GRB
  6. GRB090102: MAGIC telescope GeV observation
  7. GRB 090112B: Suzaku WAM observation of the prompt emission
  8. GRB 090113: GROND Upper Limits
  9. GRB 090113: Swift-XRT refined analysis
  10. GRB 090113: Observations from NOT
  11. GRB 090113: Enhanced Swift-XRT position
  12. GRB 090113: Swift-BAT refined analysis
  13. GRB 090113: ROTSE-III Optical Limits
  14. GRB090113: XRT position
  15. GRB 090112B: Fermi GBM Detection
  16. GRB 090113: Swift detection of a burst
  17. GRB 090112: Fermi GBM detection
  18. GRB 090109: Fermi GBM detection
  19. GRB 090108B: Fermi GBM detection
  20. GRB 090111, Swift-BAT refined analysis
  21. GRB 090111: Swift UVOT Upper Limits
  22. GRB 090108: Fermi GBM Detection
  23. GRB 090111: Swift-XRT refined analysis
  24. GRB 090111: Enhanced Swift-XRT position
  25. GRB 090111: Swift detection of a burst
  26. GRB 090107B: Suzaku WAM observation of the prompt emission
  27. GRB090107B: Fermi GBM Detection
  28. GRB 090102: WSRT Radio Observations
  29. GRB 090107B: Swift XRT afterglow confirmation
  30. GRB 090107B: Swift/UVOT Observations
  31. GRB 090107B: Swift-XRT detection of possible afterglow
  32. GRB 090107B optical observations
  33. GRB 090107B: a long GRB localized by INTEGRAL
  34. Fermi/GBM detection of GRB 081226A
  35. Fermi/GBM detection of GRB 081225
  36. GRB 090107: Swift-BAT refined analysis
  37. GRB 090107: Swift detection of a burst
  38. GRB 081231: Fermi GBM Detection
  39. GRB 090102: optical decay
  40. VLA radio upper limit on GRB 090102
  41. Swift triggered on the HMXB 1A 1118-61
  42. Konus-Wind observation of GRB 090102
  43. GRB 081229: Fermi GBM detection
  44. GRB 090102: Hobby-Eberly Telescope Spectroscopy
  45. GRB 090102: P60 Imaging and P200 Spectroscopy
  46. GRB 090102 Observations from IAC80
  47. GRB 090102: GROND observations of the optical afterglow
  48. Swift UVOT observations of GRB 090102
  49. GRB 090102: Swift-BAT refined analysis
  50. GRB 090102: Swift burst of interest
  51. GRB 090102: Swift XRT refined analysis
  52. GRB 090102: NOT redshift
  53. GRB 090102: Enhanced Swift-XRT position
  54. GRB 090102: TAROT Calern observatory optical light curve
  55. GRB 090102: REM observations of a bright afterglow
  56. GRB 090102: Swift detection of a burst with an optical counterpart
  57. GRB 090102: TAROT Calern observatory optical observations
  58. GRB 081230: GROND confirmation of the afterglow
  59. GRB 081230, Swift-BAT refined analysis
  60. GRB081230: Swift-XRT refined analysis
  61. GRB 081230 Swift/UVOT Observations
  62. GRB 081230: Enhanced Swift-XRT position
  63. GRB 081230: Swift/UVOT Detection of an Optical Afterglow
  64. GRB 081230: ROTSE-III Detection of Optical Counterpart
  65. GRB 081230: Swift detection of a burst
  66. GRB 081228: GROND confirmation of the optical/NIR afterglow
  67. GRB 081226B: Fermi GBM observation
  68. GRB 081226C: Fermi GBM detection
  69. GRB 081228, Swift-BAT refined analysis
  70. VLA radio detection of GRB 081221
  71. GRB 081228: Swift/UVOT Upper Limits
  72. GRB 081228: Swift-XRT Team refined analysis
  73. GRB 081228: detection by GROND
  74. GRB 081228: Enhanced Swift-XRT position
  75. GRB 081228: TAROT Calern observatory optical observations
  76. GRB 081228: Swift detection of a burst
  77. VLA radio observation of GRB 081221
  78. GRB 081226B: Swift XRT and UVOT upper limits
  79. GRB 081224: Suzaku WAM observation of the prompt emission
  80. GRB 081226: Swift-XRT refined analysis
  81. GRB 081226A: Swift UVOT Upper Limits
  82. GRB 081226: Second epoch of Gemini-South imaging
  83. GRB 081226A: Swift-BAT refined analysis
  84. GRB 081226B: a short-hard GRB detected by INTEGRAL
  85. GRB 081226: Gemini-South spectrum of possible afterglow
  86. GRB 081226: Gemini-South imaging
  87. GRB 081226: GROND afterglow candidate
  88. GRB 081226: Swift detection of a possible short-hard burst
  89. GRB 080810: optical observations
  90. GRB 081211B: optical observations
  91. GRB081224: LAT retraction
  92. GRB 081224: Swift-XRT observation
  93. GRB 081222: MITSuME optical observation
  94. GRB 081224: Fermi GBM Detection & LAT Localization
  95. GRB 080810: optical observations
  96. Konus-Wind observation of GRB 081222
  97. GRB 081223: Fermi GBM detection
  98. GRB 081221: GROND observations
  99. GRB 081222: Gemini-N confirmation of redshift z=2.77
  100. GRB 081222:Optical afterglow observation

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