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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"

38654 results found.

  1. Swift Trigger 150823 is HETE J1900.1-2455
  2. GRB 050815: Radio Observation
  3. GRB050814: Radio Observation
  4. GRB050817: Negative Optical Observations
  5. GRB050817: Swift-BAT Detection of a burst
  6. GRB 050814: continued fading
  7. GRB050815: Optical afterglow detection by Swift UVOT
  8. GRB050815: XRT refined analysis
  9. GRB 050813: Radio Observations
  10. GRB050815: Refined analysis of the Swift-BAT burst
  11. GRB 050815: ROTSE-III Optical Limits
  12. GRB050815: Swift XRT afterglow localization
  13. GRB050815: Swift-BAT detection of a burst
  14. GRB 050730: Third Epoch WSRT Radio Observations
  15. GRB050814: Fading red source
  16. GRB 050813: Gemini Spectra Revisited
  17. GRB050814: P60 Optical Afterglow Candidate
  18. GRB 050813: Non-fading of afterglow candidate
  19. GRB 050814: XRT refined analysis
  20. GRB050814: SWIFT/UVOT observation
  21. GRB050814: Refined analysis of the Swift-BAT burst
  22. GRB050813: Gemini Imaging
  23. GRB 050813: Gemini spectroscopy and redshifts of galaxies B and C
  24. GRB 050814: Swift XRT Afterglow Localization
  25. GRB 050814: Swift detection of a burst
  26. GRB 050813: Magellan detection of a high redshift galaxy cluster
  27. GRB050813, SDSS pre-burst observations
  28. GRB 050813: KAIT optical limit
  29. GRB 050813: Swift-BAT refined analysis
  30. GRB 050813: Photometry of object in XRT error circle
  31. GRB050813: SWIFT/UVOT observation
  32. GRB 050813: Swift XRT afterglow localization
  33. RBO GRB 050714A and GRB 050716 observations
  34. GRB 050813: Possible Short Swift-BAT GRB
  35. GRB050813 (Swift 150139): P60 Observations
  36. Swift-BAT trigger 150131 is not a GRB
  37. GRB050807(=H3889): An X-Ray Rich GRB Localized by HETE
  38. Ongoing activity of SGR 1806-20: an intermediate burst 050811
  39. GRB050803: CrAO optical observations, no OT candidate
  40. Detection of an intermediate burst from SGR 1806-20 on August 8
  41. GRB 050730: WSRT Radio Observations
  42. GRB 050803: PROMPT BVRcIc Observations
  43. GRB 050807: ROTSE-III Optical Limits
  44. GRB 050730, optical observation
  45. GRB050805b: CrAO optical limit
  46. GRB050730, optical observations
  47. GRB050803, optical observations
  48. Swift-BAT trigger 149118 is very likely not a GRB
  49. Retraction of Swift Trigger 149131 (GRB 050805B)
  50. GRB050805b: MASTER optical observations
  51. Possible GRB 050805B: Swift-BAT trigger 149131 may be a burst
  52. GRB050805a: MASTER optical candidat
  53. Swift-BAT trigger 149118 is probably not a GRB
  54. GRB050802: TNG optical observations
  55. GRB050803: Radio Observation
  56. GRB050801: Radio Observation
  57. GRB050730: Radio Detection
  58. GRB050803: CrAO optical observations, possible OT candidate
  59. GRB050803: Optical/UV Upper Limits from Swift-UVOT
  60. GRB 050803: Swift-BAT refined analysis
  61. GRB 050802.422: Fading of the afterglow and detection of the host
  62. GRB050803: MASTER further analys
  63. GRB 050803: Magellan Observations
  64. GRB 050803: early Swift XRT analysis results
  65. GRB050803: MASTER optical observations
  66. GRB050802: Tentative absorption redshift
  67. GRB050803: Swift-BAT detection of a very long burst
  68. GCN GRB observation 050713A
  69. GRB050730: FORS1 and UVES/VLT low- and high-resolution spectroscopy
  70. GRB 050802: Swift/UVOT optical and UV detections
  71. GRB050802: CrAO optical observations
  72. GRB050801: Unchanged decay slope
  73. GRB050802 radio non-detection
  74. GRB 050802: early Swift XRT analysis results
  75. GRB 050802: Swift/UVOT observations
  76. GRB 050802 : Lulin Optical follow-up observation
  77. GRB 050802: Swift-BAT refined analysis
  78. GRB050801: Optical photometry and decay index
  79. GRB 050802: XRT position
  80. GRB 050802: Swift Gamma-ray Burst
  81. GRB050801: Swift/UVOT Optical and UV detections
  82. GRB 050730: Preliminary Analysis of MIKE Spectrum
  83. GCN 050801: early Swift XRT analysis results
  84. GRB 050801: Swift-BAT refined analysis
  85. GRB 050801, SMARTS optical/IR afterglow observations
  86. GRB 050801, afterglow observations
  87. GRB 050730, corrected photometry and break?
  88. GRB 050801: ROTSE-III Early Afterglow Break
  89. GRB050801: Swift-BAT detection of a burst
  90. GRB050801: GCN XRT position is incorrect
  91. GRB 050801: ROTSE-III Detection of Possible Counterpart
  92. GRB 050730: XRT refined analysis
  93. Correction to GCN Circ 3476 on GRB050525A
  94. GRB 050730: early TAROT optical observations
  95. GRB 050726: PROMPT Rc Observations
  96. Swift/UVOT photometry of GRB050730
  97. GRB050730: Refined BAT analysis of the Swift-BAT burst
  98. GRB 050730: Swift XRT afterglow observations
  99. GRB 050730 XMM-Newton observation
  100. GRB 050730: PROMPT VRcIc Observations

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