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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"

25031 results found.

  1. GRB 070611: ROTSE-III Optical Limits
  2. GRB 070610: Swift-UVOT Upper Limits
  3. GRB 070610: OPTIMA-Burst high-time-resolution optical observations
  4. GRB 070610, Swift-BAT refined analysis
  5. GRB 070412: TAROT Calern observatory optical observations
  6. GRB 070411: TAROT Calern observatory optical observations
  7. GRB070520B: optical observations
  8. GRB070520: optical observation
  9. GRB070518: optical observation
  10. GRB070521: optical observation
  11. GRB 070531: NOT nIR observations
  12. GRB 070531: Swift-BAT refined analysis
  13. GRB 070531: I-band observations from IAC80
  14. GRB 070531: Liverpool Telescope Optical Observations
  15. GRB 070529: SARA upper limit
  16. Swift/UVOT refined analysis of GRB070529
  17. GRB 070529: Optical aterglow from MIRO
  18. GRB 070529: Swift-XRT refined analysis
  19. GRB 070529, Swift-BAT refined analysis
  20. GRB 070529: Xinglong TNT Optical Upper Limit
  21. GRB 070529: Swift detection of a burst with an optical aterglow
  22. GRB 070412: Deep Keck imaging
  23. Swift trigger 280447 is probably a Galactic transient
  24. GRB 070518, deep LBT photometry
  25. Konus-Wind observation of GRB 070521
  26. GRB070521: Second Epoch Gemini Imaging
  27. GRB 070521: Swift/UVOT Upper Limits
  28. GRB 070521, optical observation
  29. GRB 070521: Swift-XRT refined analysis
  30. GRB 070521: Keck imaging
  31. GRB070521: Gemini Observations
  32. GROND upper limits of GRB 070521
  33. GRB 070520B: SARA upper limit
  34. GRB 070520A: SARA upper limit
  35. GRB 070521: SARA upper limit
  36. GRB 070521: Subaru observations and possible host detection
  37. GRB 070520B: Swift/UVOT Upper Limits
  38. GRB 070520A: Subaru Observations
  39. GRB 070521, Swift-BAT refined analysis
  40. GRB 070520A: Swift UVOT Upper Limits
  41. GRB 070520B: Swift-XRT refined analysis
  42. GRB 070521: TAROT La Silla observatory optical observations
  43. GRB070521 - SDSS Pre-Burst Observations
  44. GRB 070521: Swift detection of a burst
  45. GRB 070520A: MITSuME Akeno optical upper limits
  46. GRB 070520B, Swift-BAT refined analysis
  47. GRB 070520A, Swift-BAT refined analysis
  48. GRB 070520A: Swift-XRT refined analysis
  49. GRB 070518: TNG observations
  50. GRB 070520B: Swift detection of a burst
  51. GRB 070520: Xinglong EST optical Upper Limit
  52. GRB 070520: Swift detection of a burst
  53. VLA observation of GRB 070518
  54. GRB 070518: Swift-XRT refined analysis
  55. GRB070518: UVOT refined analysis
  56. GRB 070518, Swift-BAT refined analysis
  57. GRB 070518: OT confirmed form Xinglong TNT observation
  58. GRB 070518: Swift detection of a burst with optical afterglow
  59. GRB070517: Swift-XRT Refined Analysis
  60. GRB 070517, Swift-BAT refined analysis
  61. GRB 070517: Optical search
  62. GRB 070517: Swift detection of a burst
  63. GRB 070509: objects inside XRT error circle
  64. GRB 070512: IPN localization and Konus spectrum of a bright burst
  65. GRB070419A: optical observations
  66. GRB 070509: Swift/UVOT Upper Limits
  67. Konus-Wind and Konus-A observation of GRB 070508
  68. GRB 070510: Swift detection of a possible burst
  69. GRB070509: Swift-XRT Refined Analysis
  70. GRB 070509, Swift-BAT refined analysis
  71. GRB 070508: Suzaku/WAM observation of the prompt emission
  72. GRB 070509: REM observations
  73. GRB070508: Swift/UVOT Observations
  74. GRB 070508, Swift-BAT refined analysis
  75. GRB 070508: REM observations
  76. GRB 070508: TAROT La Silla observatory optical observations
  77. GRB 070508: Swift detection of an intense burst with an optical counterpart
  78. GRB070506: Swift/UVOT Observations
  79. GRB070506: Swift XRT refined analysis
  80. GRB 070506, Swift-BAT Refined Analysis
  81. GRB 070506: Swift detection of a burst with optical afterglow
  82. GRB070429B: VLT observations
  83. GRB070429B: position correction
  84. GRB 070309: Swift-XRT afterglow confirmation
  85. VLA observation of GRB 070429B
  86. Swift/UVOT observations of GRB070429B
  87. GRB 070429B, Swift-BAT refined analysis
  88. Swift/UVOT observations of GRB070429A
  89. GRB 070429A, Swift-BAT refined analysis
  90. GRB 070429A: optical and NIR observations
  91. GRB 070429B: Swift XRT refined analysis
  92. GRB 070429B: ROTSE-III Optical Limits
  93. GRB 070429: ROTSE-III Optical Limits
  94. GRB 070429: Swift detection of a burst
  95. GRB 070427, Swift-BAT Refined Analysis
  96. LT monitoring of GRB070412
  97. GRB 070411: Late-time Keck imaging
  98. GRB070419B: Suzaku WAM observation of the prompt emission
  99. GRB 070420, SMARTS optical/IR afterglow observations
  100. GRB 070411, deep LBT photometry

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