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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"

3870 results found.

  1. GRB 050721A: Swift-BAT refined analysis
  2. GRB050721A: Swift-BAT detection of a weak burst
  3. GRB050716: Refined analysis of the Swift-BAT burst
  4. Konus-Wind observation of GRB 050713A
  5. GRB 050713A: RAPTOR detection of early optical emission
  6. Swift-BAT Trigger 145729 is not a GRB
  7. GRB 050713A: Swift/UVOT observation
  8. RBO RI observations of GRB 050713A
  9. GRB050713: Liverpool Telescope prompt observations
  10. GRB050713: possible I-band afterglow
  11. GRB 050713: Swift detection of Bright Burst
  12. GRB 050713A: ROTSE-III Optical Limits
  13. GRB050709: A Possible Short-Hard GRB Localized by HETE
  14. GRB 050626: Swift XRT observations
  15. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  16. Konus-Wind observation of an intermediate burst from SGR 1806-20
  17. GRB 050525a, Mid-Infrared Observations
  18. GRB050607: P60 Observations
  19. Konus-Wind observation of GRB 050603
  20. GRB 050603: Swift XRT Position
  21. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  22. GRB 050603: INTEGRAL shows it is not a short GRB
  23. Swift/BAT Detection of GRB050603
  24. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  25. GRB 050525a: SARA Observations
  26. XRF 050522: Swift XRT observation
  27. RBO Observations of GRB050520
  28. GRB 050509b: No Optical Variability in XRT Error Circle
  29. GRB050416: Afterglow detection at 188 nm with Swift UVOT
  30. GRB050509c (=H3751): An X-Ray Flash Localized By HETE
  31. Swift Detection of GRB050509b: A short duration burst
  32. GRB 050502a: Optical Observations
  33. Renewal of SGR 1806-20 activity
  34. GRB 050502A: WSRT Radio Observations
  35. GRB050502A: Optical Observations
  36. GRB 050502: Confirmed variability of the afterglow candidate +
  37. GRB050502 - Correction on the Optical Candidate from the Liverpool
  38. GRB 050502: ROTSE-III Detection of Possible Counterpart
  39. Swift-BAT Trigger 115881 is not a real GRB
  40. Swift/BAT possible detection of a weak burst GRB050430
  41. GRB 050421: IR Observations
  42. Swift Detection of GRB050421
  43. GRB050408: optical observation
  44. GRB050408: Radio Observations
  45. GRB 050408,optical observation
  46. GRB 050408, optical observations
  47. GRB 050319 : Confirmation of optical afterglow decay
  48. GRB050318: Swift XRT position
  49. GRB050309: CONCAM pre-trigger and trigger coincident optical
  50. GRB 050306: further TAROT optical data
  51. Ongoing activity of SGR 1806-20 after the giant flare
  52. GRB050215A: ROTSE-III Optical Observations
  53. GRB 050129: a weak long GRB detected with INTEGRAL
  54. SGR 1806-20: GMRT results at 240 MHz band.
  55. SGR 1806-20: low frequency GMRT results of 2005 Jan 16.
  56. GRB050117: Refined XRT position
  57. SGR 1806-20: RXTE/PCA pulse frequency during flare
  58. SGR 1806-20: Further VLA Observations
  59. SGR 1806-20: Further low frequency GMRT results
  60. SGR 1806-20: Further VLA Observations
  61. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  62. Further VLA observations of SGR 1806-20
  63. SGR 1806-20 and extragalactic short-duration GRBs
  64. Further ATCA observations of SGR 1806-20
  65. Fourth Epoch VLA observations of SGR 1806-20
  66. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  67. SGR 1806-20: Temporal and Spectral behavior of radio transient
  68. ATCA observations of SGR 1806-20
  69. SGR 1806-20, RHESSI observations of the 041227 giant flare
  70. Third epoch observations of SGR 1806-20 with VLA
  71. Second Epoch VLA observations of SGR 1806-20
  72. Second-epoch VLA observations of SGR 1806-20
  73. SGR1806: Detection of a Sudden Ionospheric Disturbance
  74. DETECTION OF POLARIZATION OF THE RADIO EMISSION FROM SGR 1806-20
  75. VLA observations of SGR 1806-20
  76. SGR1806 VLA Observations
  77. VLA observations of SGR 1806-20
  78. SGR1806-20: RXTE-PCA observation of the 041227 super-flare
  79. Detection of the SGR 1806-20 giant outburst back-scattered by the
  80. The giant outburst from SGR 1806-20
  81. Giant flare from SGR 1806-20 detected by INTEGRAL
  82. Very high activity of SGR 1806-20
  83. Summary of the recent bursts from SGR 1806-20
  84. IBAS GRB Alert # 2034
  85. Bright bursts from SGR1806-20
  86. GRB041006, submillimetre observations
  87. Konus-Wind observation of a series SGR 1806-20 bursts on 041005
  88. Bursts from SGR 1806-20: Preliminary INTEGRAL results
  89. Very strong outburst from SGR 1806-20 detected with INTEGRAL
  90. SGR 1806-20 still active
  91. GRB 040924: Second Epoch WSRT Radio Observations
  92. GRB040929,optical observation
  93. GRB040916: Optical observations
  94. ROTSE-IIIb Observations of GRB 040916 (HETE #3558)
  95. An intense burst from SGR1806-20
  96. Very bright burst detected from SGR 1806-20
  97. GRB 040827 : Planned XMM-Newton observation
  98. GRB 040827 - A long GRB detected by INTEGRAL
  99. Increase of SGR 1806-20 activity
  100. Bursting activity from SGR 1806-20 detected with IBAS

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