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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"

20258 results found.

  1. GRB 050805b: OHP optical limits
  2. GRB 050805b: TAROT optical limits
  3. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  4. GRB050802: TNG optical observations
  5. GRB050803: Radio Observation
  6. GRB 050803: RTT150 optical observations
  7. GRB050801: Radio Observation
  8. GRB050730: Radio Detection
  9. GRB 050803: Keck Observations
  10. GRB 050803: Swift-BAT refined analysis
  11. GRB 050802.422: Fading of the afterglow and detection of the host
  12. GRB 050803: TAROT optical limits
  13. GRB050802 radio non-detection
  14. GRB 050730: OHP optical observations
  15. GRB 050802: Swift-BAT refined analysis
  16. GRB050801: Optical photometry and decay index
  17. GRB 050802: Swift Gamma-ray Burst
  18. GCN 050801: early Swift XRT analysis results
  19. GRB 050730: early TAROT optical observations
  20. GRB 050726: PROMPT Rc Observations
  21. GRB 050730, spectra and optical photometry
  22. GRB 050730 XMM-Newton observation
  23. GRB050730: Swift-BAT detection of a weak burst
  24. GRB 050709: PROMPT Rc Observations
  25. GRB 050724: WHT optical observations
  26. GRB050713: analysis of the XMM-Newton observation
  27. GRB050709: Second Epoch Chandra Observation
  28. GRB 050724: Optical Variability in Nearby Galaxy
  29. GRB 050724: J-band observations
  30. GRB 050724: GMOS Imaging and Spectroscopy
  31. RXTE ASM Detection of GRB050724
  32. GRB050724: Radio Observation
  33. GRB 050724: Swift/UVOT Upper Limit
  34. GRB 050724: possible host galaxy in DSS
  35. GRB 050721A: Swift-BAT refined analysis
  36. Correction to GCN Circ 3474 on GRB050525A
  37. GRB050721A: optical decay
  38. GRB 050721: optical afterglow confirmed
  39. GRB050721A: Swift-BAT detection of a weak burst
  40. GRB 050717: PROMPT RcIc Observations
  41. GRB050714b: Radio Observation
  42. GRB050712: Radio Observations
  43. GRB050713a: Radio Observation
  44. GRB 050712, Tautenburg optical afterglow observations
  45. Swift-BAT detection of a possible GRB
  46. GRB 050714B: VLT R-band observations
  47. GRB 050717: Additional LCO observations
  48. GRB050717
  49. GRB 050716; J-band observations
  50. Konus-Wind observation of GRB 050717
  51. GRB 050717: LCO near-IR observations
  52. Swift/UVOT Observations of GRB 050717
  53. GRB 050717: Swift-BAT refined analysis
  54. GRB050717: Swift XRT position
  55. Swift detection of GRB 050717
  56. Swift UVOT Observations of GRB 050716
  57. GRB 050716: Lulin B and R band optical observations
  58. GRB050716, optical observation
  59. GRB050716: Faulkes North Telescope observation
  60. Konus-Wind observation of GRB 050713A
  61. GRB 050714B: refined XRT analysis
  62. GRB 050713b: RTT150 optical observations
  63. GRB 050714B: optical afterglow
  64. GRB 050714, R-band candidate
  65. GRB 050714, optical observations
  66. GRB 050714A: ROTSE-III Optical Limits
  67. GRB 050713A: RAPTOR detection of early optical emission
  68. GRB050713B :Swift/UVOT observations
  69. GRB050712: TNG R-band observations
  70. GRB 050713A: Swift/UVOT observation
  71. GRB050712: Swift UVOT Observation of Afterglow Emission
  72. GRB 050713A : Lulin R-band observation
  73. GRB 050713A XMM-Newton observation
  74. GRB050713B: Faulkes North Telescope observation
  75. RBO RI observations of GRB 050713A
  76. GRB050709 : Chandra source optical counterpart
  77. GRB 050712, optical observations
  78. GRB050709: Candidate X-ray Afterglow from Chandra
  79. GRB050713: possible I-band afterglow
  80. GRB 050713A: ROTSE-III Optical Limits
  81. GRB050709: Radio Observations
  82. GRB 050709: Swift UVOT and XRT observations
  83. GRB050712: UVOT candidate optical counterpart
  84. GRB 050712: Swift detection of a weak burst
  85. GRB 050709: LCO40 Observations
  86. PROMPT Rc Observations of GRB 050709
  87. GRB 050525a: PROMPT VRcIc Detections
  88. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  89. GRB 050525a: ARC 3.5-Meter SPIcam Field Calibration
  90. GRB 050408: ARC 3.5-meter NIR Observations
  91. Swift UVOT observations of GRB 050701
  92. GRB 050607, radio observations
  93. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  94. GRB050525a: HST Observations
  95. XRF 050509c: Optical monitoring
  96. XRF050509c: Radio Detection
  97. GRB 050607 optical decay
  98. GRB050607: refined analysis of prompt REM observations
  99. GRB 050607: PROMPT VRcIc Observations
  100. GRB 050607: Optical decay and spectral slope

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