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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').
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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"

36143 results found.

  1. SGR1806: Detection of a Sudden Ionospheric Disturbance
  2. GRB 041217: Optical observations
  3. GRB041219, early time observations
  4. IPN localization of giant flare from SGR1806-20
  5. GRB041219; RXTE ASM Observations
  6. NIR Observations of GRB 041219
  7. GRB041223: decay of the afterglow
  8. GRB 041224: near-infrared observations with REM
  9. GRB 041223: XRT afterglow spectrum and light curve
  10. GRB 041223 Fluence measured by Swift-BAT
  11. GRB041223: optical and NIR observations with REM
  12. GRB 041219: TAROT optical observations
  13. GRB 041218: TAROT optical observations
  14. GRB 041223: J-band observations of the afterglow
  15. GRB 041223: Detection of Optical Transient with LCO40
  16. GRB 041219c: PROMPT Observations
  17. GRB 041218: optical observations
  18. GRB 041219: Second Epoch WSRT Radio Observations
  19. GRB 041219: WSRT Radio Afterglow Detection
  20. GRB 041219: Keck IR Observations and Astrometric Refinement of the
  21. GRB 041218: Optical observations
  22. GRB 041219 : optical follow-up observations
  23. Deep RAPTOR observations during GRB 041219
  24. GRB 041218 Optical Observations
  25. GRB 041219 Optical Observations
  26. GRB041219c: Third Burst in One Day from Swift-BAT
  27. GRB041219: Optical Afterglow Detection
  28. GRB041219: Continued NIR Observations
  29. GRB 041219 ,optical observation
  30. GRB 041219: Radio Afterglow Detection
  31. GRB 041218 : Radio Observations
  32. GRB 041218: R-band optical observations
  33. GRB041219: Confirmed NIR Afterglow
  34. GRB041218: Continued P60 Optical Observations
  35. GRB 041218: Optical Observation
  36. GRB 041219: Infrared Afterglow Candidate
  37. GRB041219, BVRcIc field calibration
  38. GRB 041219: Infrared Afterglow Candidate
  39. GRB041218, BVRcIc field calibration
  40. GRB041219: Prompt Optical Observations from ROTSE-IIIb
  41. GRB041219: P60 Optical Observations
  42. GRB 041219 - A long GRB detected by INTEGRAL
  43. GRB 041219: PAIRITEL IR Observations, < 3 minutes after trigger
  44. GRB 041217: PROMPT Observations
  45. GRB041218: optical observations
  46. GRB041217: optical limit 30 min after GRB
  47. GRB 041218; optical candidate
  48. GRB 041218: Optical observations
  49. GRB 041217: LCO40 Optical Observations and Possible Candidates
  50. GRB 041218 - A long GRB detected by integral
  51. GRB041217: Optical Observations
  52. GRB041217: P60 Optical Observations
  53. GRB041217: Infrared Observations
  54. GRB041217: The First GRB Located On-Board Swift
  55. GRB041211: Faulkes Telescope continued optical monitoring
  56. Optical Transient in Lynx not a GRB
  57. Optical transient (GRB?) in Lynx
  58. Optical transient (GRB?) in Lynx, UT Dec 11.4436
  59. GRB041211: Continued P60 Observations
  60. GRB041211: RAPTOR observations
  61. GRB041211: Ashra Prototype optical observation
  62. GRB041211, Faulkes Telescope optical observation
  63. GRB041211, BVRcIc field calibration
  64. GRB 041211: Infrared Observations
  65. GRB 041211: KAIT observations
  66. GRB 041211: Optical follow-up in East Asian region
  67. GRB 041211(=H3622): A Long GRB Localized by the HETE WXM and SXC
  68. GRB041211: P60 optical imaging
  69. GRB970815: Discovery of Optical Afterglow
  70. Distribution of IBAS Alerts for NON-GRB sources
  71. Triangulation of short GRB 041116 (large error box)
  72. GRB 040924: Afterglow Color
  73. GRB 041006: GETS Optical Afterglow Observation
  74. Summary of the recent bursts from SGR 1806-20
  75. GRB 041006: Optical Observations
  76. GRB041006, late-time optical photometry
  77. IBAS GRB Alert # 2034
  78. GRB041006: RTT150 Optical Observations
  79. Bright bursts from SGR1806-20
  80. GRB 041016: BOOTES-2 simultaneous observation
  81. GRB041006: RTT150 Optical Observations
  82. GRB 041016: Optical limits
  83. GRB 041016: Optical limits in V, R, I
  84. GRB 041016:Optical limit during first minute
  85. GRB041016: MASTER: Optical observations
  86. GRB 041015: Optical Observations at Rikubetsu
  87. GRB041006: Near Infrared observations
  88. GRB 041016: Optical limit
  89. GRB 041015 R band observations
  90. GRB040924, BVRcIc field calibration
  91. GRB041015: MASTER: Optical observations
  92. GRB041015,optical observation
  93. GRB 041015: Optical limit at Osaka University
  94. GRB041015 : Optical follow-up at Kiso
  95. GRB 041015 - A long GRB detected by INTEGRAL
  96. GRB 041006 R observations in Loiano
  97. GRB041006: VLT observations of the afterglow and host galaxy
  98. GRB041006: Optical observations and Potential host galaxy
  99. GRB041006, BVRcIc field calibration
  100. GRB 040924: VLT spectroscopy

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