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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"

37514 results found.

  1. GRB 091208B: Swift-XRT refined analysis
  2. GRB091208B: Swift/UVOT refined analysis
  3. GRB 091208B: Fermi GBM observation
  4. GRB 091208B, Swift-BAT refined analysis
  5. GRB 091208A Swift-BAT refined analysis
  6. GRB 091208B: Gemini-North redshift
  7. GRB 091208B: Faulkes Telescope North and South Optical Afterglow
  8. GRB 091208A, RIMOTS optical upper limits
  9. GRB 091208B: MITSuME Akeno Optical Observation
  10. GRB 091208B: Enhanced Swift-XRT position
  11. GRB 091208B: MITSuME Okayama Optical Observation
  12. GRB 091208B, RIMOTS optical upper limits
  13. GRB 091208B: Swift detection of a burst with an optical afterglow
  14. GRB 091208B: BOOTES-3 optical afterglow
  15. GRB 091208: ROTSE-III Optical Limits
  16. GRB 091208: Swift detection of a burst
  17. A small revision to the GRB-naming convention
  18. GRB 091123: Suzaku WAM observation of the prompt emission
  19. GRB 091127: Skynet/PROMPT Observations of Possible Host Galaxy
  20. GRB 091127: GAO 150cm telescope Optical Observation
  21. GRB 091202: GTC & CAHA optical/nIR afterglow candidate
  22. GRB 091109A: GROND confirmation of redshift z = 3.5
  23. GRB091127: Continuing Swift/UVOT Observations
  24. GRB 091127, SMARTS optical/IR afterglow observations
  25. GRB091202: Swift-XRT refined analysis
  26. GRB 091202: Swift/UVOT Upper Limits
  27. GRB 091202: Liverpool Telescope observations
  28. GRB 091202: Optical and NIR observations
  29. GRB 091202 - UVOT-enhanced XRT position
  30. GRB 091127: Zadko Telescope Observations
  31. GRB 091126A: Suzaku WAM observation of the prompt emission
  32. GRB 091202: TAROT Calern observatory optical observations
  33. GRB 091202: Liverpool Telescope Observations
  34. GRB 091202: a long GRB detected by INTEGRAL
  35. GRB 091127: redshift confirmation with X-shooter
  36. GRB 091117: Chandra Observations
  37. GRB 091020: MASTER-Net optical polarization observations
  38. GRB 091127: Skynet/PROMPT Continued Observations of Fading
  39. Short X-ray Transient Detection by MAXI/GSC
  40. Konus-Wind observation of very long GRB 091123
  41. GRB 091130A: Xinglong TNT upper limit
  42. GRB 091123: Fermi GBM detection of a very long burst
  43. GRB 091126B: Fermi GBM detection
  44. GRB 091127: Suzaku WAM observation of the prompt emission
  45. GRB 091126: Fermi GBM detection
  46. GRB 091130B: Swift-XRT team refined analysis
  47. GRB 091130B: Swift-BAT refined analysis
  48. GRB 091130B: Swift/UVOT Upper Limits
  49. GRB 091127: Skynet/PROMPT Observations of Fading
  50. GRB 091130B: Enhanced Swift-XRT position
  51. Swift trigger 377436 (possible GRB 091130A) is not a burst
  52. GRB 091130B: MASTER observations
  53. GRB 091130B: SDSS galaxy at XRT location
  54. GRB 091130B: Swift detection of a burst
  55. GRB 091130: MASTER observations
  56. GRB 091130: Swift detection of a possible burst
  57. GRB 091127: Radio observations
  58. GRB 091128: Fermi GBM detection
  59. Konus-Wind observation of GRB 091127
  60. GRB 091127: TAROT La Silla observatory optical observations
  61. GRB 091127: optical observations
  62. GRB 091127: LABOCA/APEX submm observations
  63. GRB 091127: Further NOT optical observations
  64. GRB 091127: Fermi GBM detection
  65. GRB 091127: MASTER early optical transient polarimetry
  66. GRB 091127: Gemini-N redshift
  67. GRB 091127: Swift-XRT afterglow detection and analysis
  68. GRB 091127: TAROT La Silla observatory optical decay
  69. GRB 091127: Swift/UVOT observations
  70. GRB 091127: CAHA 1.23m I-band observations
  71. GRB 091127: Swift-BAT refined analysis
  72. GRB 091127: NOT observations
  73. GRB 091127 : GROND observations
  74. GRB 091127: REM NIR afterglow detection
  75. GRB 091127: Swift/UVOT Detection of an Optical Afterglow
  76. GRB 091127: Liverpool Telescope afterglow candidate
  77. GRB 091127: Swift detection of a burst
  78. IPN Triangulation of GRB091120
  79. Konus-Wind observation of GRB 091120
  80. GRB 091120: MAXI GSC detection
  81. GRB 091120: Fermi GBM observation
  82. GRB 091117A: Suzaku WAM observation of the prompt emission
  83. GRB 091117: TNG optical observations
  84. GRB 091117A: Swift/UVOT followup observations
  85. GRB 091117: 2nd epoch of Magellan optical observations
  86. GRB 091117: VLA radio observations
  87. GRB 091117: Swift-XRT observations
  88. GRB 091117 BAT refined analysis
  89. GRB 091117: Evidence for Variability of XRT Source #1
  90. GRB 091117: Swift XRT refined analysis
  91. GRB 091117: Gemini-North spectroscopy of DSS galaxy
  92. Konus-Wind observations of GRB 091117A
  93. GRB 091117: Magellan optical observations
  94. GRB 091117: XRT source coincident with a DSS galaxy
  95. GRB 091117: OSN I-band observations
  96. GRB 091117A Detected in ground analysis of BAT data and IPN triangulation
  97. GRB 091112: Suzaku WAM observation of the prompt emission
  98. GRB 091102A: Suzaku WAM observation of the prompt emission
  99. GRB 091109B: Suzaku WAM observation of the prompt emission
  100. GRB091111: Swift XRT refined analysis

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