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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"

42862 results found.

  1. GRB 050820: Early RAPTOR detections
  2. GRB 050820 Swift-BAT refined analysis
  3. GRB 050820: P60 Temporal Decay Index
  4. GRB 050820: High Resolution Spectroscopy from Keck
  5. GRB050819: refined XRT analysis
  6. GRB050819: RTT150 optical observations
  7. GRB 050820: Swift detection of a GRB
  8. GRB050820: Optical afterglow from P60
  9. GRB 050819 Swift-BAT refined analysis
  10. GRB050819: Swift XRT position
  11. GRB050819: Swift-BAT detection of a weak burst
  12. Swift-BAT trigger 150993 is not a GRB
  13. Swift Trigger 150823 is HETE J1900.1-2455
  14. GRB 050817: Optical observations
  15. GRB 050815: Radio Observation
  16. GRB050814: Radio Observation
  17. GRB050817: Negative Optical Observations
  18. GRB050817: Swift-BAT Detection of a burst
  19. GRB050815: Optical afterglow detection by Swift UVOT
  20. GRB050815: XRT refined analysis
  21. GRB 050813: Radio Observations
  22. GRB050815: Refined analysis of the Swift-BAT burst
  23. GRB050815: Swift XRT afterglow localization
  24. GRB050815: Swift-BAT detection of a burst
  25. GRB 050730: Third Epoch WSRT Radio Observations
  26. GRB050814: Fading red source
  27. GRB 050813: Gemini Spectra Revisited
  28. GRB050814: P60 Optical Afterglow Candidate
  29. GRB 050813: Non-fading of afterglow candidate
  30. GRB 050814: XRT refined analysis
  31. GRB050814: SWIFT/UVOT observation
  32. GRB050814: Refined analysis of the Swift-BAT burst
  33. GRB050813: Gemini Imaging
  34. GRB 050813: Gemini spectroscopy and redshifts of galaxies B and C
  35. GRB 050814: Swift XRT Afterglow Localization
  36. GRB 050814: Swift detection of a burst
  37. GRB 050813: Magellan detection of a high redshift galaxy cluster
  38. GRB050813: RTT150 optical observations
  39. GRB 050813: I-band observations
  40. GRB050813, SDSS pre-burst observations
  41. GRB 050813: KAIT optical limit
  42. GRB 050813: Swift-BAT refined analysis
  43. GRB 050813: Photometry of object in XRT error circle
  44. GRB050813: SWIFT/UVOT observation
  45. GRB 050813: Swift XRT afterglow localization
  46. RBO GRB 050714A and GRB 050716 observations
  47. GRB 050813: Possible Short Swift-BAT GRB
  48. GRB050813 (Swift 150139): P60 Observations
  49. Swift-BAT trigger 150131 is not a GRB
  50. GRB050807(=H3889): An X-Ray Rich GRB Localized by HETE
  51. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  52. GRB050803: CrAO optical observations, no OT candidate
  53. Detection of an intermediate burst from SGR 1806-20 on August 8
  54. GRB 050730: WSRT Radio Observations
  55. GRB 050803: PROMPT BVRcIc Observations
  56. GRB 050730, optical observation
  57. GRB050805b: CrAO optical limit
  58. GRB050805a : Null detection report
  59. GRB050730, optical observations
  60. GRB050803, optical observations
  61. Swift-BAT trigger 149118 is very likely not a GRB
  62. Retraction of Swift Trigger 149131 (GRB 050805B)
  63. GRB 050805b: OHP optical limits
  64. GRB 050805b: TAROT optical limits
  65. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  66. Swift-BAT trigger 149118 is probably not a GRB
  67. GRB050803: Radio Observation
  68. GRB 050803: RTT150 optical observations
  69. GRB050801: Radio Observation
  70. GRB050730: Radio Detection
  71. GRB050803: CrAO optical observations, possible OT candidate
  72. GRB 050803: Keck Observations
  73. GRB 050803: Swift-BAT refined analysis
  74. GRB 050802.422: Fading of the afterglow and detection of the host
  75. GRB 050803: Magellan Observations
  76. GRB 050803: early Swift XRT analysis results
  77. GRB 050803: TAROT optical limits
  78. GRB050802: Tentative absorption redshift
  79. GRB050803: Swift-BAT detection of a very long burst
  80. GCN GRB observation 050713A
  81. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  82. GRB 050802: Swift/UVOT optical and UV detections
  83. GRB050802: CrAO optical observations
  84. GRB050801: Unchanged decay slope
  85. GRB 050730: OHP optical observations
  86. GRB 050802: early Swift XRT analysis results
  87. GRB 050802: Swift/UVOT observations
  88. GRB 050802: Swift-BAT refined analysis
  89. GRB050801: Optical photometry and decay index
  90. GRB 050802: XRT position
  91. GRB 050802: Swift Gamma-ray Burst
  92. GRB050801: Swift/UVOT Optical and UV detections
  93. GRB 050730: Preliminary Analysis of MIKE Spectrum
  94. GCN 050801: early Swift XRT analysis results
  95. GRB 050801: Swift-BAT refined analysis
  96. GRB 050801, SMARTS optical/IR afterglow observations
  97. GRB 050801, afterglow observations
  98. GRB 050730, corrected photometry and break?
  99. GRB 050801: ROTSE-III Early Afterglow Break
  100. GRB050801: Swift-BAT detection of a burst

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