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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"

21459 results found.

  1. GRB070621: RTT150 optical observations
  2. GRB 070621: VLT optical observations
  3. GRB 070621: Swift/UVOT Upper Limits
  4. Keck Laser Guide Star Adaptive Optics Imaging of GRB 070621
  5. GRB 070621: Swift-BAT refined analysis
  6. WHT observations of GRB070621
  7. GRB070621: Swift XRT refined analysis
  8. GRB 070621: Gemini South optical imaging
  9. GRB 070621: UVOT-enhanced XRT position
  10. GRB 070621: NOT observations
  11. GRB070621: OPTIMA-Burst optical upper limit
  12. GRB 070621: TAROT Calern observatory optical observations
  13. GRB 070621: Watcher Observations
  14. GRB 070621: ROTSE-III Prompt Optical Limits
  15. GRB 070621: Swift detection of a burst
  16. GMRT upper limit of GRB 070610/SWIFT J195509.6+261406 in 610 MHz
  17. Swift/UVOT detection of GRB070616 optical afterglow.
  18. GRB070616: Optical Observation by MITSuME Akeno
  19. GRB 070612B: Optical Observation by MITSuME Akeno
  20. GRB 070616, Swift-BAT further refined analysis
  21. GRB 070616: Swift XRT refined circular
  22. GRB 070616: BTA optical observations
  23. Swift/UVOT observations of GRB070616
  24. GRB 070616: TLS observation
  25. Swift XRT observations of the INTEGRAL burst GRB070615: Possible
  26. GRB 070616, Swift-BAT partial refined analysis
  27. GRB 070616: Swift detection of a burst
  28. GRB 070612B: optical observations
  29. UVOT Observations of INTEGRAL burst GRB070615
  30. SWIFT J195509.6+261406 (GRB 070610): further observations
  31. GRB 070612A: Rapid Decay
  32. GRB 070612A: Suzaku/WAM observation of the prompt emission
  33. SWIFT J195509.6+261406 / GRB 070610: OPTIMA-Burst observations
  34. GRB 070611: Watcher Observations
  35. Swift Trigger 282176 is Cygnus X-1
  36. GRB 070612A: MDM Observations
  37. GRB 070612B: SARA upper limit
  38. GRB 070612B, Swift-BAT refined analysis
  39. GRB 070612A, Swift-BAT refined analysis
  40. GRB 070612B: Swift-XRT refined analysis
  41. SWIFT J195509.6+261406 / GRB 070610: SWIFT continued observations
  42. GRB 070612B: Swift/UVOT upper limits
  43. GRB 070612B: FRAM limit
  44. GRB070612B: P60 Observations
  45. GRB 070612B: KAIT limits
  46. GRB 070612B: Swift XRT position from downlink data
  47. GRB 070610: TAROT Calern observatory optical observations
  48. GRB 070610: MITSuME OAO optical upper limit
  49. GRB 070612B: Swift detection of a burst
  50. GRB 070612: Swift detection of a burst
  51. GRB 070610: Swift-XRT refined analysis
  52. GRB 070610: TLS RRM sees flaring behaviour - Galactic transient?
  53. GRB 070611: Swift/UVOT Observations
  54. GRB 070611: Swift-XRT refined analysis
  55. GRB 070611, Swift-BAT refined analysis
  56. GRB 070610: Optical observations from OSN
  57. GRB 070610: Watcher Observations
  58. GRB 070611: ROTSE-III Detection of Late Rising Optical Counterpart
  59. GRB 070611; Swift-XRT position
  60. GRB 070611: ROTSE-III Optical Limits
  61. GRB 070611: Swift detection of a burst
  62. GRB 070610: Swift-UVOT Upper Limits
  63. GRB 070610: OPTIMA-Burst high-time-resolution optical observations
  64. GRB 070610, Swift-BAT refined analysis
  65. GRB 070610; Swift-XRT position
  66. GRB 070610: Swift detection of a burst
  67. GRB 070412: TAROT Calern observatory optical observations
  68. GRB 070411: TAROT Calern observatory optical observations
  69. GRB070520B: optical observations
  70. GRB070520: optical observation
  71. GRB070521: optical observation
  72. Swift/UVOT refined analysis of GRB070531
  73. GRB 070531: NOT nIR observations
  74. GRB 070531: Swift-BAT refined analysis
  75. GRB 070531: I-band observations from IAC80
  76. GRB 070531: Swift-XRT position
  77. GRB 070531: Liverpool Telescope Optical Observations
  78. GRB 070531: Swift detection of a burst
  79. Swift/UVOT refined analysis of GRB070529
  80. GRB 070529: MARGE Observations
  81. GRB 070529: Optical aterglow from MIRO
  82. GRB 070529: Swift-XRT refined analysis
  83. GRB 070529, Swift-BAT refined analysis
  84. GRB 070529: Swift detection of a burst with an optical aterglow
  85. GRB 070412: Deep Keck imaging
  86. Swift Triggers 280447, 280450 and 280451 are invalid
  87. Swift trigger 280447 is probably a Galactic transient
  88. GRB 070518: MARGE Observations
  89. GRB 070521: pseudo-z ~ 2.28 from prompt emission spectrum
  90. Konus-Wind observation of GRB 070521
  91. GRB070521: Second Epoch Gemini Imaging
  92. GRB070521: NIR observations
  93. GRB070520B: NIR observations
  94. GRB 070521: Swift/UVOT Upper Limits
  95. GRB 070521: Swift-XRT refined analysis
  96. GRB 070521: Keck imaging
  97. GROND upper limits of GRB 070521
  98. GRB 070521 Milagro GeV/TeV Observations
  99. GRB 070521: SARA upper limit
  100. GRB 070521: Subaru observations and possible host detection

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