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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"

42898 results found.

  1. GRB 060204C: Liverpool Telescopes optical limit
  2. GRB 060204C: Swift-BAT detection of a burst
  3. GRB 060124: Radio Observations
  4. GRB060204B: Faulkes OT candidate
  5. GRB 060204B: ART optical limit
  6. GRB 060204A: further INTEGRAL results
  7. GRB060204B - SDSS pre-burst observations
  8. GRB 060203: Swift-BAT refined analysis
  9. GRB 060204B: Swift detection of a burst
  10. GRB 060204: a long GRB detected by INTEGRAL
  11. GRB 060202: UKIRT/WFCAM K-band and KeckI/LRIS I-band Observation
  12. GRB 060203: RTT150 optical observations
  13. GRB060203: Swift XRT Team Refined Analysis
  14. GRB060203 - Swift UVOT observation
  15. Swift-BAT trigger is GRB 060203
  16. GRB 060203: IR Counterpart
  17. GRB060203: Observations with SARA
  18. GRB 060203: P60 Confirmation of Optical Afterglow
  19. Possible GRB 060203: candidate optical counterpart
  20. Swift BAT Trigger 180151: Swift XRT source detection
  21. Possible GRB 060203: optical observations at Asiago
  22. GRB 060202: PROMPT Observations
  23. Swift-BAT trigger 180151 is unknown origin at this time
  24. GRB 060202: GETS observation
  25. GRB 060202: Gemini-N J, H, K_s observations
  26. GRB 060202: Near-IR Observation with UKIRT/WFCAM
  27. GRB 060202: Optical Afterglow Candidate from Keck/LRIS
  28. GRB 060202: Refined analysis of the Swift-BAT burst
  29. GRB060202, optical observation
  30. GRB 060202: Swift/UVOT upper limits
  31. GRB 060202: Swift XRT Team Refined Analysis
  32. GRB 060202 : Lulin R and I band limit
  33. GRB060202: Faulkes North observation
  34. GRB 060202: Swift detection of a burst
  35. GRB 060121: Gemini Late-time Observations
  36. GRB 060130: PROMPT Observations
  37. GRB060130: Further R-band imaging
  38. GRB 060130: Swift/XRT observation
  39. GRB 051211A: MDM Observations
  40. GRB 060123: Gemini spectroscopy of the putative host galaxy
  41. GRB 060123: VLA Radio Observations
  42. GRB060130: Optical imaging
  43. GRB060130: REM infrared observations
  44. GRB 060130, SMARTS optical observations
  45. GRB 060130: further INTEGRAL IBIS results
  46. GRB 060130: a long GRB detected with INTEGRAL
  47. Possible GRB 051221B: MDM Correction
  48. GRB050121: optical observation
  49. GRB050121b: optical observation
  50. GRB 060121: Confirmation of NIR Afterglow
  51. GRB 060123: Swift refined analysis of an unusual GRB
  52. GRB060124, BVRcIc field calibration
  53. GRB060105: refined analysis of the Suzaku observation
  54. GRB060124 optical observations
  55. GRB 060121: Probable Detection of NIR Afterglow
  56. GRB 060116 HST observations
  57. GRB 060124: HETE detection and spectrum of the main peak
  58. Refined XRT Position for GRB 060123
  59. Konus-Wind observation of GRB 060124
  60. GRB060124: detailed XRT analysis
  61. GRB 060124 Optical Observations
  62. GRB 060124: ART optical limits during the burst
  63. GRB060123: Optical and IR Imaging
  64. GRB 060123: P200 Observations
  65. GRB 060124: Keck optical spectrum
  66. GRB 060124: Keck Absorption Redshift
  67. GRB 060124: MDM Optical Spectrum
  68. GRB 060124: XRT refined analysis
  69. GRB 060124: R band Observations
  70. GRB060124: optical observations at Asiago
  71. GRB 060124: Extremely long burst, Swift-BAT refined analysis
  72. GRB060123: SDSS pre-burst observations
  73. GRB 060123: Swift detection of a very long, faint burst
  74. GRB 060116: Further analysis of VLT photometry and optical spectroscopy
  75. GRB 060121: OHP optical limits
  76. GRB 060124: TAROT optical limits
  77. GRB 060124: Swift/UVOT Observation
  78. GRB 060124: Confirmation of the Afterglow
  79. GRB 060124: XRT position
  80. GRB 060124: Optical Afterglow Candidate from Tautenburg
  81. GRB060124, optical observation
  82. GRB 050124 : Kiso Optical limit
  83. GRB 060124: Optical Observations at Tautenburg
  84. GRB 060117: Suzaku WAM observation of the prompt emission
  85. GRB 060111B: Suzaku WAM observation of the prompt emission
  86. GRB 060124: Swift-BAT detection of a burst
  87. GRB 060116: Radio Detection
  88. GRB 060116: MARGE optical observations
  89. GRB 060121: Swift/UVOT upper limits
  90. GRB 060121: Liverpool Telescopes optical limits
  91. GRB 060121: Swift XRT refined analysis
  92. Konus-Wind observation of GRB 060121
  93. GRB 060121: I-band Limits
  94. GRB 060121: Confirmation of Afterglow
  95. GRB 060121: candidate optical counterpart
  96. GRB 060121: Swift XRT refined position
  97. GRB060121: SARA Observations
  98. GRB 060121: optical observations
  99. GRB 060121: Infrared Observations
  100. GRB 060121: optical observations

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