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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"

3821 results found.

  1. GRB 060202: Gemini-N J, H, K_s observations
  2. GRB 051211A: MDM Observations
  3. GRB060130: REM infrared observations
  4. GRB 060116: MARGE optical observations
  5. GRB060121: SARA Observations
  6. GRB 060121: optical observations
  7. GRB 060114: Swift/UVOT Observations
  8. GRB 060111B: Refined analysis of the Swift-BAT burst
  9. GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare
  10. GRB 051221: Swift/UVOT upper limits
  11. GRB 051211B: Swift XRT confirmation of the afterglow
  12. An extraordinary long burst on December 3 from SGR1806-20
  13. Possible resuming of the SGR 1806-20 activity
  14. GRB 051117A: Refined analysis of the Swift-BAT burst
  15. GRB050925: analysis of the XMM-Newton observation
  16. GRB/SGR 050925: XMM-Newton ToO observation
  17. GRB 051111a: IR photometry
  18. GRB 051008 Tautenburg Supernova Search
  19. GRB 051109: Rc and Ic observations
  20. GRB051103: MASTER: OT limit and host galaxy candidates
  21. IPN triangulation and Konus spectrum of the bright short/hard GRB051103
  22. GRB 051105b: ART optical limits
  23. GRB051028 SARA Observation
  24. SGR 1806-20: continued moderate activity seen with INTEGRAL
  25. GRB051021.63
  26. GRB 051016b: Optical limit
  27. GRB 051016B: Swift detection of a soft burst
  28. GRB050805A: Rc optical observations
  29. GRB/SGR 050925: IR Observations
  30. GRB050925: Swift-BAT detection of a short burst
  31. GRB 050915: Swift XRT refined analysis
  32. GRB 050915: ROTSE-III optical limits
  33. GRB050911: Upper limit on X-ray afterglow
  34. GRB 050906: Swift-BAT refined analysis
  35. GRB 050906: Bright galaxy in BAT error box
  36. GRB 050824: ROTSE-III Optical Limits
  37. GRB 050822: Swift detection of a long burst
  38. GRB050820: refined XRT analysis
  39. GRB 050820: P60 Temporal Decay Index
  40. GRB 050820: Swift detection of a GRB
  41. GRB050820: Optical afterglow from P60
  42. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  43. Detection of an intermediate burst from SGR 1806-20 on August 8
  44. GRB050805a: MASTER optical candidat
  45. GCN 050801: early Swift XRT analysis results
  46. GRB 050730, corrected photometry and break?
  47. GRB050801: Swift-BAT detection of a burst
  48. GRB 050730: early TAROT optical observations
  49. GRB 050730, spectra and optical photometry
  50. GRB 050724: Secure Host Redshift from Keck
  51. GRB050713: analysis of the XMM-Newton observation
  52. GRB 050721A: Swift-BAT refined analysis
  53. GRB050721A: Swift-BAT detection of a weak burst
  54. GRB050716: Refined analysis of the Swift-BAT burst
  55. Konus-Wind observation of GRB 050713A
  56. GRB 050713A: RAPTOR detection of early optical emission
  57. Swift-BAT Trigger 145729 is not a GRB
  58. GRB 050713A: Swift/UVOT observation
  59. RBO RI observations of GRB 050713A
  60. GRB050713: Liverpool Telescope prompt observations
  61. GRB050713: possible I-band afterglow
  62. GRB 050713: Swift detection of Bright Burst
  63. GRB 050713A: ROTSE-III Optical Limits
  64. GRB050709: A Possible Short-Hard GRB Localized by HETE
  65. GRB 050626: Swift XRT observations
  66. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  67. Konus-Wind observation of an intermediate burst from SGR 1806-20
  68. GRB 050525a, Mid-Infrared Observations
  69. GRB050607: P60 Observations
  70. Konus-Wind observation of GRB 050603
  71. GRB 050603: Swift XRT Position
  72. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  73. GRB 050603: INTEGRAL shows it is not a short GRB
  74. Swift/BAT Detection of GRB050603
  75. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  76. GRB 050525a: SARA Observations
  77. XRF 050522: Swift XRT observation
  78. RBO Observations of GRB050520
  79. GRB 050509b: No Optical Variability in XRT Error Circle
  80. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  81. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  82. Swift Detection of GRB050509b: A short duration burst
  83. GRB 050502a: Optical Observations
  84. Renewal of SGR 1806-20 activity
  85. GRB 050502A: WSRT Radio Observations
  86. GRB050502A: Optical Observations
  87. GRB 050502: Confirmed variability of the afterglow candidate +
  88. GRB050502 - Correction on the Optical Candidate from the Liverpool
  89. GRB 050502: ROTSE-III Detection of Possible Counterpart
  90. Swift-BAT Trigger 115881 is not a real GRB
  91. Swift/BAT possible detection of a weak burst GRB050430
  92. GRB 050421: IR Observations
  93. Swift Detection of GRB050421
  94. GRB050408: optical observation
  95. GRB050408: Radio Observations
  96. GRB 050408,optical observation
  97. GRB 050408, optical observations
  98. GRB 050319 : Confirmation of optical afterglow decay
  99. GRB050318: Swift XRT position
  100. GRB050309: CONCAM pre-trigger and trigger coincident optical

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