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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.

Advanced Search Examples (click to copy):

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

23687 results found.

  1. GRB 050318: SWIFT-UVOT refined analysis
  2. GRB 050319 : Confirmation of optical afterglow decay
  3. GRB 050319: Swift-BAT refined analysis
  4. GRB050319,optical observation
  5. Swift Detection of GRB 050319
  6. GRB 050318: Swift/UVOT detection of afterglow emission
  7. Swift-BAT detection of GRB 050318
  8. GRB 050315, SMARTS optical afterglow decay
  9. GRB050223: analysis of the XMM-Newton observation
  10. GRB050316: MASTER before, simultanious and follow up optical
  11. GRB050316: MASTER optical observations
  12. GRB 050315: Swift-BAT further refined analysis
  13. GRB 050315 I-band observations
  14. GRB050315: Radio afterglow
  15. GRB050315: Swift-BAT Refined analysis
  16. GRB 050219b: Gemini/GNIRS near-infrared spectroscopy
  17. Swift-BAT detection of GRB 050315
  18. GRB050309: CONCAM pre-trigger and trigger coincident optical
  19. GRB 050306: optical afterglow
  20. Swift-BAT trigger 107873: No Swift XRT counterpart
  21. GRB 050306: Confirmation of X-ray afterglow
  22. GRB 050309, Early optical limits from RAPTOR
  23. GRB050309: Early optical limit from P60
  24. Swift-BAT trigger 107873 (GRB050309): possible X-ray counterparts
  25. GRB 050306: CORRECTION to date of observation
  26. GRB 050306: No Swift UVOT Optical Counterpart Detected
  27. GRB 050306: REM optical-infrared observations
  28. GRB 050306: Possible X-ray Afterglow Position from the Swift
  29. GRB 050306,optical observation
  30. GRB 050306: Swift-BAT detection of a long burst
  31. Ongoing activity of SGR 1806-20 after the giant flare
  32. GRB050215B: Late-Time Swift UVOT Observations
  33. PROMPT VRcIc Observations of GRB 050223
  34. IBAS GRB Alert #2321
  35. INTEGRAL detection of GRB 050223
  36. GRB 050223 Swift/BAT detection of a burst
  37. GRB 050223: Swift XRT Position
  38. GRB050219b: CORRECTION to time of UVOT observations
  39. GRB050219b: No Swift UVOT Detection of Afterglow Emission
  40. GRB 050219b: Swift-BAT detection of a burst
  41. GRB 050219: Swift-BAT detection of a burst
  42. GRB050215b: Swift UVOT Detection of Afterglow Emission
  43. GRB050215b: P60 Optical Observations
  44. GRB 050215b: Swift XRT Observations
  45. Swift-BAT detects two bursts: GRB050215a and GRB050215b
  46. GRB 050215b, BOOTES-1B optical limit
  47. GRB050209: REM optical observations
  48. GRB 050209 Optical observations
  49. GRB050209: P60 Optical Observations
  50. Further analysis of the short Swift-BAT GRB 050202
  51. GRB 050129: Optical observations
  52. GRB 050202: Optical observations with LCO40
  53. GRB 050128 Optical observation with REM
  54. GRB 050129: a weak long GRB detected with INTEGRAL
  55. GRB050128: Faulkes Telescope South observations
  56. GRB050128,optical observations
  57. GRB050126: Updated Swift XRT Position
  58. GRB050126: MASTER optical limit for KECK OT
  59. GRB050126: MASTER optical observations
  60. GRB 050126: Prompt XRT detection and localization
  61. GRB 050124 I-band observation
  62. GRB050124,optical observation
  63. GRB 050124: Swift XRT Detection of X-ray Afterglow Emission
  64. GRB050123,optical observation
  65. GRB050123: P60 Observations
  66. GRB 050123(=H3666): A GRB Localized in Real Time by HETE
  67. Unusual optical transient (GRB ???)
  68. GRB050117a: Refined analysis
  69. GRB050117: Palomar WIRC Ks-band observations
  70. GRB050117: Refined XRT position
  71. GRB050117: MASTER optical observations
  72. MASTER:GRB050117 SWIFT
  73. GRB050117: Swift-BAT detection of a long multi-peaked burst
  74. Triangulation of Short Hard GRB050112 (large error box)
  75. SGR1806: Optical Transient Candidates in SOHO/LASCO Images
  76. Further ATCA observations of SGR 1806-20
  77. SGR 1806-20: Low frequency GMRT results; submission to GCN circulars
  78. SGR 1806-20, RHESSI observations of the 041227 giant flare
  79. Third epoch observations of SGR 1806-20 with VLA
  80. Second-epoch VLA observations of SGR 1806-20
  81. SGR1806 VLA Observations
  82. GRB041219, early time observations
  83. Detection of the SGR 1806-20 giant outburst back-scattered by the
  84. The giant outburst from SGR 1806-20
  85. IPN localization of giant flare from SGR1806-20
  86. Giant flare from SGR 1806-20 detected by INTEGRAL
  87. GRB041219; RXTE ASM Observations
  88. Swift-BAT Time History of GRB041219
  89. GRB 041219c: PROMPT Observations
  90. GRB 041218: optical observations
  91. Very high activity of SGR 1806-20
  92. GRB 041219 : optical follow-up observations
  93. GRB 041218 Optical Observations
  94. GRB 041219 Optical Observations
  95. GRB041219: Continued NIR Observations
  96. GRB 041219 ,optical observation
  97. GRB 041218: R-band optical observations
  98. GRB041218: Liverpool Telescope optical observations
  99. GRB041218: Continued P60 Optical Observations
  100. GRB 041219: Infrared Afterglow Candidate

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