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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

22211 results found.

  1. Ongoing activity of SGR 1806-20 after the giant flare
  2. GRB050215B: Late-Time Swift UVOT Observations
  3. GRB 050126: Confirmation of the NIR afterglow candidate
  4. PROMPT VRcIc Observations of GRB 050223
  5. XRF/GRB 050215B: Radio Observations
  6. GRB 050219b: candidate NIR afterglow
  7. GRB 050223: optical observations
  8. GRB050223: No Swift UVOT Detection of Afterglow Emission
  9. GRB050223: ROTSE-III Optical Observations
  10. GRB 050223: Swift XRT Position
  11. HETE-2 Observations of GRB 050215b (=U11570): A Likely X-Ray Flash
  12. GRB050219b: CORRECTION to time of UVOT observations
  13. GRB050215b: Faulkes North and SDSS limits on UKIRT candidate
  14. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  15. GRB 050219a: Optical observations from LCO
  16. GRB 050219b: Optical and near-IR observations from LCO
  17. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  18. GRB 050219b: CORRECTION: Swift XRT Position
  19. GRB 050219b: Swift XRT Position
  20. GRB 050219a, optical observations
  21. GRB 050219a: Refined XRT position
  22. GRB050219a: No Swift UVOT Detection of Afterglow Emission
  23. GRB050215b: Swift UVOT Detection of Afterglow Emission
  24. GRB 050215B: Radio Observations
  25. GRB 050215b: XRT confirmation of IR afterglow candidate
  26. GRB050215b: P60 Optical Observations
  27. GRB 050215b: Swift XRT Source Variability
  28. GRB 050215B: candidate afterglow
  29. GRB 050215b : Lulin follow-up observation
  30. GRB 050215b, BOOTES-2 simultaneous optical observations
  31. GRB 050215b: Swift XRT Observations
  32. GRB050215b: No Swift UVOT Detection of Afterglow Emission
  33. GRB050215a: No Swift UVOT Detection of Afterglow Emission
  34. Swift-BAT detects two bursts: GRB050215a and GRB050215b
  35. GRB050215B: ROTSE-III optical observations
  36. GRB050215A: ROTSE-III Optical Observations
  37. GRB050209: TAROT optical observations
  38. GRB 050209(=U11568): Duration and spectrum
  39. short/hard GRB 050202, optical observations
  40. GRB050209: REM optical observations
  41. GRB 050209 Optical observations
  42. GRB050209: P60 Optical Observations
  43. GRB 050128: Radio observations
  44. GRB 050202: Second epoch radio observations
  45. GRB 050129: Optical observations
  46. GRB050202: Radio Observations
  47. GRB 050202: Optical observations with LCO40
  48. GRB 050128 Optical observation with REM
  49. GRB050128: Faulkes Telescope South observations
  50. GRB 050124: Radio Observations
  51. GRB 050128: near-infrared observations with REM
  52. GRB050128,optical observations
  53. GRB 050126: A NIR afterglow candidate in the revised XRT error circle
  54. GRB 050126: Radio Observations
  55. GRB050128 Swift-BAT observations
  56. GRB 050128: Swift XRT prompt afterglow position
  57. HETE #3667: P60 Observations
  58. GRB 050124: K-band afterglow observations
  59. GRB050126: MASTER optical observations
  60. GRB 050126: Prompt XRT detection and localization
  61. GRB050124: No Swift UVOT Detection of Afterglow Emission
  62. GRB 050124, SMARTS optical/IR observations
  63. GRB 050117a: Radio Observations
  64. GRB 050124: NIR Candidates from Keck/NIRC
  65. GRB 050124 : Lulin R-band follow-up observation
  66. GRB050124: Updated Swift XRT Position and Fluxes
  67. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  68. GRB 050123 : I-band follow-up observation
  69. GRB 050123: KAIT observations
  70. GRB050123: P60 Observations
  71. CFHTLS optical transient unlikely to be a GRB
  72. GRB050117a: Radio Observations
  73. GRB 041224 and GRB 041226: BOOTES-2 simultaneous observations
  74. GRB050117: Palomar WIRC Ks-band observations
  75. GRB 050117, I-band observations
  76. GRB050117: Refined XRT position
  77. GRB050117: MASTER optical observations
  78. MASTER:GRB050117 SWIFT
  79. GRB050117: Swift-BAT detection of a long multi-peaked burst
  80. SGR 1806-20: Further VLA Observations
  81. SGR 1806-20: Further low frequency GMRT results
  82. SGR 1806-20: Further VLA Observations
  83. SGR1806-20: Swift-BAT observations of two additional bursts
  84. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  85. Further VLA observations of SGR 1806-20
  86. Further ATCA observations of SGR 1806-20
  87. Fourth Epoch VLA observations of SGR 1806-20
  88. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  89. ATCA observations of SGR 1806-20
  90. SGR 1806-20, RHESSI observations of the 041227 giant flare
  91. Third epoch observations of SGR 1806-20 with VLA
  92. Second Epoch VLA observations of SGR 1806-20
  93. Second-epoch VLA observations of SGR 1806-20
  94. SGR1806: Detection of a Sudden Ionospheric Disturbance
  95. VLA observations of SGR 1806-20
  96. SGR1806 VLA Observations
  97. VLA observations of SGR 1806-20
  98. GRB 041217: Optical observations
  99. GRB041219, early time observations
  100. The giant outburst from SGR 1806-20

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