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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"

32714 results found.

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

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