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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

15685 results found.

  1. GRB060203: WHT Z-band observations
  2. GRB060204C: optical observation
  3. GRB 060204B: BVRi-band detections of optical afterglow
  4. GRB 060204A: FRAM optical observations
  5. GRB 060204C: optical observations
  6. GRB 060204B: ART early limit
  7. GRB060204B: Swift XRT Team Refined Analysis
  8. GRB 060204C: BOOTES-IR optical limits
  9. GRB 060204C: Liverpool Telescopes optical limit
  10. GRB 060204C: ROTSE-III Optical Limits
  11. GRB 060124: Radio Observations
  12. GRB 060204B: ART optical limit
  13. GRB060204B, optical observation
  14. GRB 060203: RTT150 optical observations
  15. GRB060203: Swift XRT Team Refined Analysis
  16. GRB060203 - Swift UVOT observation
  17. GRB 060203: P60 Confirmation of Optical Afterglow
  18. Possible GRB 060203: candidate optical counterpart
  19. Possible GRB 060203: optical observations at Asiago
  20. GRB 060202: Optical Afterglow Candidate from Keck/LRIS
  21. GRB060202, optical observation
  22. GRB060202: Faulkes North observation
  23. GRB 051211A: MDM Observations
  24. GRB060130: Optical imaging
  25. GRB 060130, SMARTS optical observations
  26. GRB 060130: FRAM optical observations
  27. Possible GRB 051221B: MDM Correction
  28. GRB050121: optical observation
  29. GRB050121b: optical observation
  30. GRB060124: optical observation
  31. GRB060124: optical observations
  32. GRB060124, BVRcIc field calibration
  33. GRB060124 optical observations
  34. GRB 060121: Probable Detection of NIR Afterglow
  35. GRB060124: optical observation
  36. GRB 060116 HST observations
  37. GRB 060124: HETE detection and spectrum of the main peak
  38. Refined XRT Position for GRB 060123
  39. GRB060124: detailed XRT analysis
  40. GRB 060124 Optical Observations
  41. GRB 060124: ART optical limits during the burst
  42. GRB060123: Optical and IR Imaging
  43. GRB 060124: Keck optical spectrum
  44. GRB 060124: MDM Optical Spectrum
  45. GRB 060124 : Optical observation at Xinglong and Kiso
  46. GRB060124: optical observations at Asiago
  47. GRB 060116: Further analysis of VLT photometry and optical spectroscopy
  48. GRB 060121: OHP optical limits
  49. GRB 060124: TAROT optical limits
  50. GRB 060124: Swift/UVOT Observation
  51. GRB 060124: Confirmation of the Afterglow
  52. GRB 060124: XRT position
  53. GRB 060124: Optical Afterglow Candidate from Tautenburg
  54. GRB060124, optical observation
  55. GRB 050124 : Kiso Optical limit
  56. GRB 060124: Optical Observations at Tautenburg
  57. GRB060124:MASTER optical observation
  58. GRB 060116: MARGE optical observations
  59. GRB 060121: Liverpool Telescopes optical limits
  60. GRB 060121: I-band Limits
  61. GRB 060121: Confirmation of Afterglow
  62. GRB 060121: candidate optical counterpart
  63. GRB 060121: optical observations
  64. GRB 060121: optical observations
  65. GRB 060121: Optical imaging
  66. GRB 060121 (=H4010): Results of preliminary spectral analysis
  67. GRB 060121: A bright short/hard GRB localized by HETE-2 SXC
  68. GRB 060121: A bright short/hard GRB localized by HETE-2 WXM
  69. HETE Alert 4006: MASTER promt optical limit
  70. GRB060108: photometric redshift determination
  71. GRB 060117: FRAM refined analysis
  72. GRB 060117: FRAM optical afterglow candidate
  73. GRB 060116: VLT optical observations
  74. GRB060115: REM observations
  75. GRB 060116 : Lulin optical limit
  76. GRB 060116: ROTSE-III Optical Limits
  77. GRB 060115: absorption redshift
  78. GRB 060114: REM observations
  79. GRB 060115: Swift XRT refined analysis
  80. GRB 060115: OT finding chart
  81. GRB060115, optical observation
  82. GRB 060115: MITSuME optical afterglow candidate
  83. GRB060114, optical observation
  84. GRB 060108: IR observations of afterglow
  85. GRB 060108: Evidence for an XRT Position Offset
  86. GRB 060111B: Swift XRT refined analysis
  87. GRB 060111B: MITSuME detection of optical afterglow
  88. GRB 060111B: TAROT optical observation
  89. GRB060111A: RTT150 optical observations
  90. GRB060111B: RTT150, possible host galaxy
  91. GRB 060111B: ROTSE-III Detection of Optical Counterpart Flare
  92. GRB060111.2:_MASTER optical limit
  93. GRB 060111: TAROT optical observation
  94. GRB 060111: ROTSE-III Optical Limits
  95. GRB 060110: Mitsume optical observations
  96. GRB 060110a: RAPTOR detection of early optical emission.
  97. GRB 060110: ROTSE-III Confirmation of Optical Counterpart
  98. GRB060110, optical observation
  99. GRB 060110: Optical observation
  100. GRB 060110: Optical limit

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