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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"

18659 results found.

  1. GRB 070318: Swift/UVOT Continued Observations
  2. GRB 070318, Swift-BAT refined analysis
  3. GRB 070318: Swift detection of a burst with an optical afterglow
  4. GRB 070311: Late Central Engine Activity Optical Flare??
  5. VLA observation of GRB 070311
  6. GRB 070309: variability of the XRT afterglow candidate
  7. GRB 070311: Swift/UVOT Upper Limits
  8. GRB 070311: Swift-XRT refined analysis
  9. GRB070309: Swift/XRT possible afterglow detection
  10. GRB 070125: Chandra X-ray Confirmation of Jet Break
  11. GRB 070309: Swift/UVOT Upper Limits
  12. Swift UVOT Finding Charts for GRB 070309
  13. GRB 070125: X-ray light curve analysis
  14. VLA observation of GRB 070306
  15. GRB 070306: NOT observations
  16. GRB 070306 Swift/UVOT refined analysis
  17. GRB 070306, Swift-BAT refined analysis
  18. GRB 070306: XRT Team Refined Analysis
  19. GRB070306 - SDSS Pre-burst Observations
  20. GRB 070306: Swift detection of a burst
  21. GRB070227: Swift-XRT refined analysis
  22. GRB 070125, deep late-time optical observation
  23. VLA observation of GRB 070224
  24. GRB 070227: optical observations
  25. GRB 070223: Optical Observations
  26. GRB 070227: optical observations
  27. GRB 070227: Swift/UVOT Upper Limits
  28. GRB 070227: TAROT La Silla observatory optical observations
  29. GRB 070227, Swift-BAT refined analysis
  30. GRB070227: possible X-ray afterglow detection
  31. GRB 070227: Swift detection of a burst in ground analysis
  32. GRB 070224: Optical afterglow confirmation
  33. GRB 070224: Swift/UVOT Upper Limits
  34. GRB070224: Swift-XRT Astrometrically Corrected Position
  35. VLA observation of GRB 070223
  36. VLA observation of GRB 070220
  37. GRB070224: Magellan Imaging Observations
  38. GRB070224: Gemini Imaging Observations
  39. GRB 070224: SARA upper limit
  40. GRB070224: Swift-XRT Refined Analysis
  41. GRB 070224, Swift-BAT refined analysis
  42. GRB 070224: MASTER-Net refind analysis
  43. GRB 070224: MASTER-VWF-Kislovodsk observations
  44. GRB 070224: Swift detection of a burst
  45. GRB070223: Swift/UVOT refined analysis
  46. GRB 070223, Swift-BAT refined analysis
  47. GRB070223: MASTER-VWF-Kislovodsk observations
  48. GRB 070223: Swift-XRT Refined Analysis
  49. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  50. GRB 070223: MDM Observations
  51. GRB070223: Swift burst
  52. Konus-Wind and Konus-A observations of GRB 070220
  53. GRB 070220 Swift-BAT Refined Analysis
  54. Swift/UVOT refined analysis of GRB070220
  55. GRB 070209: Swift XRT refined analysis
  56. GRB 070220: Swift-XRT Refined Analysis
  57. GRB 070220: Swift detection of a burst
  58. GRB070219: MASTER-VWF-Kislovodsk observations
  59. GRB 070219: XRT Refined Analysis
  60. GRB 070219: Swift/UVOT Upper limits
  61. GRB 070219, Swift-BAT refined analysis
  62. GRB 070219: ROTSE-III Optical Limits
  63. GRB070219 - SDSS Pre-Burst Observations
  64. GRB 070219: Swift detection of a burst
  65. Swift-BAT trigger 260304 is NOT a burst or transient
  66. GRB 070209: Swift XRT analysis
  67. GRB 070208: MARGE Optical Observations
  68. IPN localization of very bright long hard GRB 070207
  69. IPN localization of very intense short GRB 070201
  70. GRB 070209, Swift-BAT refined analysis of the short hard burst
  71. GRB 070209: Swift detection of a short hard burst
  72. GRB 070208: Swift XRT refined analysis
  73. GRB 070208: RAPTOR detection of early afterglow onset
  74. GRB 070208: MDM Optical Decay
  75. GRB 070208, Swift-BAT refined analysis
  76. GRB070208: Faulkes Telescope North Afterglow Identification
  77. GRB 070208: ROTSE-III Optical Limits
  78. GRB 070208: MDM Observations
  79. GRB 070208: Swift detection of a burst
  80. Swift-BAT trigger 259527 is a Cosmic Ray Shower
  81. GRB070124: Swift-XRT Follow-up Observation
  82. GRB070126: Swift-XRT Observation
  83. GRB 070129: Swift/UVOT Upper limits
  84. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  85. GRB061217: MAGIC telescope GeV observation
  86. GRB 070129, Swift-BAT refined analysis of a particularly long
  87. GRB 070129: Swift-XRT Refined Analysis
  88. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  89. GRB 070129: Swift detection of a burst
  90. GRB 070126: Swift/UVOT refined analysis
  91. GRB070126: Swift-XRT possible detection of an afterglow
  92. GRB 070125: UVOT Detection in Ultraviolet Filters
  93. GRB 070126, Swift-BAT refined analysis of a very faint burst
  94. GRB070124: Swift-XRT Observation
  95. Possible GRB 070126: Swift/UVOT Upper Limit
  96. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  97. GRB 070125: pseudo-z~1.5 from spectral parameters of the prompt emission
  98. GRB070125: Swift-XRT Refined Analysis
  99. GRB 070126?: Swift detection of a possible burst
  100. IPN-BAT localization of GRB070125 (very long duration, intense)

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