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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"

45719 results found.

  1. GRB050803, optical observations
  2. Swift-BAT trigger 149118 is very likely not a GRB
  3. Retraction of Swift Trigger 149131 (GRB 050805B)
  4. GRB 050805b: OHP optical limits
  5. GRB 050805b: TAROT optical limits
  6. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  7. Swift-BAT trigger 149118 is probably not a GRB
  8. GRB050802: TNG optical observations
  9. GRB050803: Radio Observation
  10. GRB 050803: RTT150 optical observations
  11. GRB050801: Radio Observation
  12. GRB050730: Radio Detection
  13. GRB050803: CrAO optical observations, possible OT candidate
  14. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  15. GRB 050803: Keck Observations
  16. GRB 050803: Swift-BAT refined analysis
  17. GRB 050802.422: Fading of the afterglow and detection of the host
  18. GRB050803: MASTER further analys
  19. GRB 050803, optical observations
  20. GRB 050803: Magellan Observations
  21. GRB 050803: early Swift XRT analysis results
  22. GRB 050803: TAROT optical limits
  23. GRB050803: MASTER optical observations
  24. GRB050802: Tentative absorption redshift
  25. GRB050803: Swift-BAT detection of a very long burst
  26. GCN GRB observation 050713A
  27. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  28. GRB 050802: Swift/UVOT optical and UV detections
  29. GRB050802: CrAO optical observations
  30. GRB050801: Unchanged decay slope
  31. GRB050802 radio non-detection
  32. GRB 050730: OHP optical observations
  33. GRB 050802: early Swift XRT analysis results
  34. GRB 050802: Swift/UVOT observations
  35. GRB 050802 : Lulin Optical follow-up observation
  36. GRB 050802: Swift-BAT refined analysis
  37. GRB050801: Optical photometry and decay index
  38. GRB 050802: XRT position
  39. GRB 050802: Swift Gamma-ray Burst
  40. GRB050801: Swift/UVOT Optical and UV detections
  41. GRB 050730: Preliminary Analysis of MIKE Spectrum
  42. GCN 050801: early Swift XRT analysis results
  43. GRB 050801: Swift-BAT refined analysis
  44. GRB 050801, SMARTS optical/IR afterglow observations
  45. GRB 050801, afterglow observations
  46. GRB 050730, corrected photometry and break?
  47. GRB 050801: ROTSE-III Early Afterglow Break
  48. GRB050801: Swift-BAT detection of a burst
  49. GRB 050801: ROTSE-III Detection of Possible Counterpart
  50. GRB 050730: XRT refined analysis
  51. Correction to GCN Circ 3476 on GRB050525A
  52. GRB 050730: early TAROT optical observations
  53. GRB 050726: PROMPT Rc Observations
  54. GRB 050730: RTT150 optical observations
  55. Swift/UVOT photometry of GRB050730
  56. GRB 050730, spectra and optical photometry
  57. GRB050730: Refined BAT analysis of the Swift-BAT burst
  58. GRB 050730: Swift XRT afterglow observations
  59. GRB 050730 XMM-Newton observation
  60. GRB 050730: PROMPT VRcIc Observations
  61. GRB050730, afterglow observations
  62. GRB050730: confirmation of redshift
  63. GRB 050730: Redshift Measurement based on Magellan/MIKE Observations
  64. GRB 050730, SMARTS optical/IR afterglow observations
  65. GRB 050730 : Planned XMM-Newton observation
  66. GRB050730: Liverpool Telescope optical observations
  67. GRB 050730, optical candidate
  68. GRB050730: Swift-BAT detection of a weak burst
  69. GRB 050713A: Swift XRT extended light curve
  70. GRB 050709: PROMPT Rc Observations
  71. GRB050713b: Maidanak optical observations
  72. GRB 050724: Secure Host Redshift from Keck
  73. GRB 050724: WHT optical observations
  74. GRB050726: Swift UVOT observations
  75. GRB 050724: Chandra Observations of the X-ray Afterglow
  76. GRB050724: Refined Radio Position
  77. GRB050713: analysis of the XMM-Newton observation
  78. GRB 050724, SMARTS optical/IR afterglow observations
  79. GRB 050726, SMARTS optical/IR observations
  80. Swift-BAT trigger 147918 is not a real GRB
  81. GRB 050727: RTT150 optical observations
  82. GRB050724: VLT observations of the variable source
  83. GRB050727: KAIT optical limit
  84. GRB050709: Second Epoch Chandra Observation
  85. GRB 050726: PROMPT Rc Observations
  86. GRB050709: Second Epoch Chandra Observation
  87. GRB 050724: dust-scattered X-ray halo detected in SWIFT/XRT observation
  88. GRB050724: Further Radio Observations
  89. GRB 050726: early Swift XRT analysis results
  90. GRB050726: Swift-BAT detection of a weak burst
  91. GRB 050724: Optical Variability in Nearby Galaxy
  92. GRB 050724: J-band observations
  93. GRB 050724: GMOS Imaging and Spectroscopy
  94. GRB 050724: SWIFT XRT refined position
  95. RXTE ASM Detection of GRB050724
  96. GRB050724: Radio Observation
  97. GRB 050724: spectroscopy of object in the XRT error circle
  98. GRB 050724: Optical limit
  99. GRB 050724: optical and near-IR observations
  100. GRB 050724: Optical imaging/astrometry

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