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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"

32740 results found.

  1. GRB 050803: RTT150 optical observations
  2. GRB050801: Radio Observation
  3. GRB050730: Radio Detection
  4. GRB050803: CrAO optical observations, possible OT candidate
  5. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  6. GRB 050803: Keck Observations
  7. GRB 050803: Swift-BAT refined analysis
  8. GRB 050802.422: Fading of the afterglow and detection of the host
  9. GRB050803: MASTER further analys
  10. GRB 050803, optical observations
  11. GRB 050803: Magellan Observations
  12. GRB 050803: early Swift XRT analysis results
  13. GRB050802: Tentative absorption redshift
  14. GCN GRB observation 050713A
  15. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  16. GRB 050802: Swift/UVOT optical and UV detections
  17. GRB050802: CrAO optical observations
  18. GRB050801: Unchanged decay slope
  19. GRB050802 radio non-detection
  20. GRB 050802: early Swift XRT analysis results
  21. GRB 050802: Swift/UVOT observations
  22. GRB 050802: Swift-BAT refined analysis
  23. GRB050801: Optical photometry and decay index
  24. GRB 050802: XRT position
  25. GRB 050802: Swift Gamma-ray Burst
  26. GRB050801: Swift/UVOT Optical and UV detections
  27. GCN 050801: early Swift XRT analysis results
  28. GRB 050801: Swift-BAT refined analysis
  29. GRB 050801, SMARTS optical/IR afterglow observations
  30. GRB 050801, afterglow observations
  31. GRB 050730, corrected photometry and break?
  32. GRB 050801: ROTSE-III Early Afterglow Break
  33. GRB050801: Swift-BAT detection of a burst
  34. GRB050801: GCN XRT position is incorrect
  35. GRB 050801: ROTSE-III Detection of Possible Counterpart
  36. GRB 050730: XRT refined analysis
  37. Correction to GCN Circ 3476 on GRB050525A
  38. GRB 050730: early TAROT optical observations
  39. GRB 050726: PROMPT Rc Observations
  40. GRB 050730: RTT150 optical observations
  41. Swift/UVOT photometry of GRB050730
  42. GRB 050730, spectra and optical photometry
  43. GRB050730: Refined BAT analysis of the Swift-BAT burst
  44. GRB 050730: Swift XRT afterglow observations
  45. GRB 050730 XMM-Newton observation
  46. GRB 050730: PROMPT VRcIc Observations
  47. GRB050730, afterglow observations
  48. GRB050730: confirmation of redshift
  49. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  50. GRB 050730, SMARTS optical/IR afterglow observations
  51. GRB050730: Liverpool Telescope optical observations
  52. GRB 050709: PROMPT Rc Observations
  53. GRB050713b: Maidanak optical observations
  54. GRB 050724: Secure Host Redshift from Keck
  55. GRB 050724: WHT optical observations
  56. GRB050726: Swift UVOT observations
  57. GRB 050724: Chandra Observations of the X-ray Afterglow
  58. GRB050724: Refined Radio Position
  59. GRB050713: analysis of the XMM-Newton observation
  60. GRB 050724, SMARTS optical/IR afterglow observations
  61. GRB 050726, SMARTS optical/IR observations
  62. Swift-BAT trigger 147918 is not a real GRB
  63. GRB050724: VLT observations of the variable source
  64. GRB050709: Second Epoch Chandra Observation
  65. GRB 050726: PROMPT Rc Observations
  66. GRB050709: Second Epoch Chandra Observation
  67. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  68. GRB050724: Further Radio Observations
  69. GRB 050726: early Swift XRT analysis results
  70. GRB050726: Swift-BAT detection of a weak burst
  71. GRB 050724: Optical Variability in Nearby Galaxy
  72. GRB 050724: J-band observations
  73. GRB 050724: GMOS Imaging and Spectroscopy
  74. GRB 050724: SWIFT XRT refined position
  75. RXTE ASM Detection of GRB050724
  76. GRB050724: Radio Observation
  77. GRB 050724: spectroscopy of object in the XRT error circle
  78. GRB 050724: Optical limit
  79. GRB 050724: optical and near-IR observations
  80. GRB 050724: Optical imaging/astrometry
  81. GRB 050724: RTT150 optical observations
  82. GRB 050724: Swift/UVOT Upper Limit
  83. GRB 050724: early Swift XRT analysis results
  84. GRB 050724 : Lulin early R-band monitoring observations
  85. GRB050724: Refined analysis of the Swift-BAT possible short burst
  86. GRB 050724: possible host galaxy in DSS
  87. Swift-BAT trigger 147325 is not due to a real GRB
  88. GRB050723: XRT distributed coordinates are not related to the burst
  89. GRB 050721: early afterglow light curve
  90. GRB 050721A: Swift-BAT refined analysis
  91. Correction to GCN Circ 3474 on GRB050525A
  92. GRB 050721A: Early Swift XRT analysis results
  93. GRB050721A: optical decay
  94. GRB 050721: optical afterglow confirmed
  95. Swift BAT Trigger 146986 is SWIFT J1753.5-0127
  96. GRB 050721a: Optical Observations
  97. GRB 050709: Refined Spectral and Temporal Properties
  98. GRB 050717: PROMPT RcIc Observations
  99. GRB050714b: Radio Observation
  100. GRB050712: Radio Observations

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