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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"

25014 results found.

  1. GRB060210: Swift/UVOT Upper Limits
  2. GRB 060211B: Swift-XRT Team refined analysis
  3. GRB 060210: Optical Observations
  4. GRB 060211: Swift detection of a long burst
  5. GRB 060210: Refined analysis of the Swift-BAT burst
  6. GRB060210: Swift XRT Refined Analysis
  7. GRB 060210 : Xinglong and Lulin optical limit
  8. GRB 060210: optical evolution
  9. GRB 060210: Swift detection of a burst
  10. GRB060210: Optical afterglow
  11. GRB 060209 : TAROT optical observation
  12. GRB 060203: Swift/UVOT upper limits
  13. GRB 060121 : WIDGET Pre-trigger limit
  14. GRB060204a: Swift XRT Source is not GRB Afterglow
  15. GRB 060206: optical observations at Asiago
  16. GRB 060206: IR Detection of the Afterglow
  17. GRB 060206: Super-LOTIS observations
  18. GRB060204A: Swift/UVOT observations
  19. GRB 060206: Swift-BAT refined analysis
  20. GRB060206: SDSS Pre-Burst Observations
  21. GRB060206 - Swift UVOT Confirmation of Optical Afterglow
  22. GRB060206: Swift-BAT detection of a burst
  23. GRB 060204C: XRT analysis of Swift J061223.0+701243.9
  24. GRB060204C: optical observation
  25. GRB 060204A: Swift XRT upper limit
  26. GRB 060204A: FRAM optical observations
  27. GRB060204B: Swift/UVOT refined analysis
  28. GRB 060204C: optical observations
  29. Swift XRT Observation of GRB 060204C
  30. GRB 060204B: Swift-BAT refined analysis
  31. GRB 060204B: ART early limit
  32. GRB 060204b: Keck/LRIS Afterglow Confirmation
  33. GRB 060204C: Liverpool Telescopes optical limit
  34. GRB 060204C: Swift-BAT detection of a burst
  35. GRB 060204A: further INTEGRAL results
  36. GRB060204B, optical observation
  37. GRB060204B - SDSS pre-burst observations
  38. GRB 060203: Swift-BAT refined analysis
  39. GRB 060204B: Swift detection of a burst
  40. GRB 060202: UKIRT/WFCAM K-band and KeckI/LRIS I-band Observation
  41. GRB 060203: RTT150 optical observations
  42. GRB 060203: IR Counterpart
  43. Possible GRB 060203: optical observations at Asiago
  44. GRB 060202: PROMPT Observations
  45. GRB 060202: GETS observation
  46. GRB 060202: Gemini-N J, H, K_s observations
  47. GRB 060202: Near-IR Observation with UKIRT/WFCAM
  48. GRB 060202: Optical Afterglow Candidate from Keck/LRIS
  49. GRB 060202: Refined analysis of the Swift-BAT burst
  50. GRB060202, optical observation
  51. GRB 060202: Swift/UVOT upper limits
  52. GRB 060121: Gemini Late-time Observations
  53. GRB 060130: PROMPT Observations
  54. GRB060130: Further R-band imaging
  55. GRB 060130: Swift/XRT observation
  56. GRB 060123: Gemini spectroscopy of the putative host galaxy
  57. GRB060130: Optical imaging
  58. GRB060130: REM infrared observations
  59. GRB 060130, SMARTS optical observations
  60. GRB 060130: FRAM optical observations
  61. GRB 060130: further INTEGRAL IBIS results
  62. GRB 060121: Confirmation of NIR Afterglow
  63. GRB 060123: Swift refined analysis of an unusual GRB
  64. GRB060124, BVRcIc field calibration
  65. GRB 060121: Probable Detection of NIR Afterglow
  66. GRB 060116 HST observations
  67. GRB 060124: HETE detection and spectrum of the main peak
  68. GRB060124: detailed XRT analysis
  69. GRB 060124: ART optical limits during the burst
  70. GRB060123: Optical and IR Imaging
  71. GRB 060123: P200 Observations
  72. GRB 060124: XRT refined analysis
  73. GRB 060124: R band Observations
  74. GRB 060124 : Optical observation at Xinglong and Kiso
  75. GRB060124: optical observations at Asiago
  76. GRB060123: SDSS pre-burst observations
  77. GRB 060116: Further analysis of VLT photometry and optical spectroscopy
  78. GRB 060121: OHP optical limits
  79. GRB 060124: TAROT optical limits
  80. GRB060124, optical observation
  81. GRB 060124: Optical Observations at Tautenburg
  82. GRB 060117: Suzaku WAM observation of the prompt emission
  83. GRB 060111B: Suzaku WAM observation of the prompt emission
  84. GRB 060124: Swift-BAT detection of a burst
  85. GRB 060121: Liverpool Telescopes optical limits
  86. GRB 060121: Swift XRT refined analysis
  87. Konus-Wind observation of GRB 060121
  88. GRB 060121: candidate optical counterpart
  89. GRB 060121: Infrared Observations
  90. GRB 060121: optical observations
  91. GRB 060121: Optical imaging
  92. GRB060121 - SDSS pre-burst observations
  93. HETE Alert 4006: MASTER promt optical limit
  94. GRB060117 - ATCA 3/6cm radio limits - correction
  95. GRB060117 - ATCA 3/6cm radio limits
  96. GRB 060116: photometric redshift - the farthest GRB?
  97. Konus-Wind observation of GRB 060117
  98. GRB 060116: UKIRT IR Observations
  99. GRB 060117: Refined analysis of the Swift-BAT burst
  100. GRB 060117: FRAM optical afterglow candidate

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