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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"

32710 results found.

  1. GRB 050730, corrected photometry and break?
  2. GRB 050801: ROTSE-III Early Afterglow Break
  3. GRB050801: Swift-BAT detection of a burst
  4. GRB050801: GCN XRT position is incorrect
  5. GRB 050801: ROTSE-III Detection of Possible Counterpart
  6. GRB 050730: XRT refined analysis
  7. Correction to GCN Circ 3476 on GRB050525A
  8. GRB 050730: early TAROT optical observations
  9. GRB 050726: PROMPT Rc Observations
  10. GRB 050730: RTT150 optical observations
  11. Swift/UVOT photometry of GRB050730
  12. GRB 050730, spectra and optical photometry
  13. GRB050730: Refined BAT analysis of the Swift-BAT burst
  14. GRB 050730: Swift XRT afterglow observations
  15. GRB 050730 XMM-Newton observation
  16. GRB 050730: PROMPT VRcIc Observations
  17. GRB050730, afterglow observations
  18. GRB050730: confirmation of redshift
  19. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  20. GRB 050730, SMARTS optical/IR afterglow observations
  21. GRB050730: Liverpool Telescope optical observations
  22. GRB 050709: PROMPT Rc Observations
  23. GRB050713b: Maidanak optical observations
  24. GRB 050724: Secure Host Redshift from Keck
  25. GRB 050724: WHT optical observations
  26. GRB050726: Swift UVOT observations
  27. GRB 050724: Chandra Observations of the X-ray Afterglow
  28. GRB050724: Refined Radio Position
  29. GRB050713: analysis of the XMM-Newton observation
  30. GRB 050724, SMARTS optical/IR afterglow observations
  31. GRB 050726, SMARTS optical/IR observations
  32. Swift-BAT trigger 147918 is not a real GRB
  33. GRB050724: VLT observations of the variable source
  34. GRB050709: Second Epoch Chandra Observation
  35. GRB 050726: PROMPT Rc Observations
  36. GRB050709: Second Epoch Chandra Observation
  37. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  38. GRB050724: Further Radio Observations
  39. GRB 050726: early Swift XRT analysis results
  40. GRB050726: Swift-BAT detection of a weak burst
  41. GRB 050724: Optical Variability in Nearby Galaxy
  42. GRB 050724: J-band observations
  43. GRB 050724: GMOS Imaging and Spectroscopy
  44. GRB 050724: SWIFT XRT refined position
  45. RXTE ASM Detection of GRB050724
  46. GRB050724: Radio Observation
  47. GRB 050724: spectroscopy of object in the XRT error circle
  48. GRB 050724: Optical limit
  49. GRB 050724: optical and near-IR observations
  50. GRB 050724: Optical imaging/astrometry
  51. GRB 050724: RTT150 optical observations
  52. GRB 050724: Swift/UVOT Upper Limit
  53. GRB 050724: early Swift XRT analysis results
  54. GRB 050724 : Lulin early R-band monitoring observations
  55. GRB050724: Refined analysis of the Swift-BAT possible short burst
  56. GRB 050724: possible host galaxy in DSS
  57. Swift-BAT trigger 147325 is not due to a real GRB
  58. GRB050723: XRT distributed coordinates are not related to the burst
  59. GRB 050721: early afterglow light curve
  60. GRB 050721A: Swift-BAT refined analysis
  61. Correction to GCN Circ 3474 on GRB050525A
  62. GRB 050721A: Early Swift XRT analysis results
  63. GRB050721A: optical decay
  64. GRB 050721: optical afterglow confirmed
  65. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  66. GRB 050721a: Optical Observations
  67. GRB 050709: Refined Spectral and Temporal Properties
  68. GRB 050717: PROMPT RcIc Observations
  69. GRB050714b: Radio Observation
  70. GRB050712: Radio Observations
  71. GRB 050714a: Refined XRT analysis and afterglow confirmation
  72. GRB050713a: Radio Observation
  73. Swift-BAT trigger 146731 is not a real GRB
  74. GRB 050712, Tautenburg optical afterglow observations
  75. GRB 050714B: VLT R-band observations
  76. GRB 050717: Additional LCO observations
  77. GRB050717
  78. GRB 050716; J-band observations
  79. Konus-Wind observation of GRB 050717
  80. GRB 050717: LCO near-IR observations
  81. Swift/UVOT Observations of GRB 050717
  82. GRB 050717: Swift-BAT refined analysis
  83. GRB 050717: Refined XRT analysis.
  84. GRB050712: optical limits
  85. GRB050717: Swift XRT position
  86. GRB 050716 - UKIRT identification of candidate afterglow
  87. Swift UVOT Observations of GRB 050716
  88. GRB 050716: Refined XRT analysis.
  89. GRB050716: Refined analysis of the Swift-BAT burst
  90. GRB 050716: Lulin B and R band optical observations
  91. GRB050716, optical observation
  92. GRB 050716: Optical Observations
  93. GRB050716: Faulkes North Telescope observation
  94. GRB050716: Correction to sign in XRT coordinate
  95. GRB050715: Refined analysis of the Swift-BAT burst
  96. Swift UVOT Observations of GRB 050714B
  97. Konus-Wind observation of GRB 050713A
  98. GRB 050714B: refined XRT analysis
  99. GRB 050713b: RTT150 optical observations
  100. GRB 050714B: candidate afterglow does not fade

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