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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"

19349 results found.

  1. GRB 070309: Swift/UVOT Upper Limits
  2. Swift UVOT Finding Charts for GRB 070309
  3. GRB 070125: X-ray light curve analysis
  4. VLA observation of GRB 070306
  5. GRB 070306: NOT observations
  6. GRB 070306 Swift/UVOT refined analysis
  7. GRB 070306, Swift-BAT refined analysis
  8. GRB 070306: XRT Team Refined Analysis
  9. GRB070306 - SDSS Pre-burst Observations
  10. GRB 070306: Swift detection of a burst
  11. GRB070227: Swift-XRT refined analysis
  12. GRB 070125, deep late-time optical observation
  13. VLA observation of GRB 070224
  14. GRB 070227: optical observations
  15. GRB 070223: Optical Observations
  16. GRB 070227: optical observations
  17. GRB 070227: Swift/UVOT Upper Limits
  18. GRB 070227: TAROT La Silla observatory optical observations
  19. GRB 070227, Swift-BAT refined analysis
  20. GRB070227: possible X-ray afterglow detection
  21. GRB 070227: Swift detection of a burst in ground analysis
  22. GRB 070224: Optical afterglow confirmation
  23. GRB 070224: Swift/UVOT Upper Limits
  24. GRB070224: Swift-XRT Astrometrically Corrected Position
  25. VLA observation of GRB 070223
  26. VLA observation of GRB 070220
  27. GRB070224: Magellan Imaging Observations
  28. GRB070224: Gemini Imaging Observations
  29. GRB 070224: SARA upper limit
  30. GRB070224: Swift-XRT Refined Analysis
  31. GRB 070224, Swift-BAT refined analysis
  32. GRB 070224: MASTER-Net refind analysis
  33. GRB 070224: MASTER-VWF-Kislovodsk observations
  34. GRB 070224: Swift detection of a burst
  35. GRB070223: Swift/UVOT refined analysis
  36. GRB 070223, Swift-BAT refined analysis
  37. GRB070223: MASTER-VWF-Kislovodsk observations
  38. GRB 070223: Swift-XRT Refined Analysis
  39. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  40. GRB 070223: MDM Observations
  41. GRB070223: Swift burst
  42. Konus-Wind and Konus-A observations of GRB 070220
  43. GRB 070220 Swift-BAT Refined Analysis
  44. Swift/UVOT refined analysis of GRB070220
  45. GRB 070209: Swift XRT refined analysis
  46. GRB 070220: Swift-XRT Refined Analysis
  47. GRB 070220: Swift detection of a burst
  48. GRB070219: MASTER-VWF-Kislovodsk observations
  49. GRB 070219: XRT Refined Analysis
  50. GRB 070219: Swift/UVOT Upper limits
  51. GRB 070219, Swift-BAT refined analysis
  52. GRB 070219: ROTSE-III Optical Limits
  53. GRB070219 - SDSS Pre-Burst Observations
  54. GRB 070219: Swift detection of a burst
  55. Swift-BAT trigger 260304 is NOT a burst or transient
  56. GRB 070209: Swift XRT analysis
  57. GRB 070208: MARGE Optical Observations
  58. IPN localization of very bright long hard GRB 070207
  59. IPN localization of very intense short GRB 070201
  60. GRB 070209, Swift-BAT refined analysis of the short hard burst
  61. GRB 070209: Swift detection of a short hard burst
  62. GRB 070208: Swift XRT refined analysis
  63. GRB 070208: RAPTOR detection of early afterglow onset
  64. GRB 070208: MDM Optical Decay
  65. GRB 070208, Swift-BAT refined analysis
  66. GRB070208: Faulkes Telescope North Afterglow Identification
  67. GRB 070208: ROTSE-III Optical Limits
  68. GRB 070208: MDM Observations
  69. GRB 070208: Swift detection of a burst
  70. Swift-BAT trigger 259527 is a Cosmic Ray Shower
  71. GRB070124: Swift-XRT Follow-up Observation
  72. GRB070126: Swift-XRT Observation
  73. GRB 070129: Swift/UVOT Upper limits
  74. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  75. GRB061217: MAGIC telescope GeV observation
  76. GRB 070129, Swift-BAT refined analysis of a particularly long
  77. GRB 070129: Swift-XRT Refined Analysis
  78. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  79. GRB 070129: Swift detection of a burst
  80. GRB 070126: Swift/UVOT refined analysis
  81. GRB070126: Swift-XRT possible detection of an afterglow
  82. GRB 070125: UVOT Detection in Ultraviolet Filters
  83. GRB 070126, Swift-BAT refined analysis of a very faint burst
  84. GRB070124: Swift-XRT Observation
  85. Possible GRB 070126: Swift/UVOT Upper Limit
  86. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  87. GRB 070125: pseudo-z~1.5 from spectral parameters of the prompt emission
  88. GRB070125: Swift-XRT Refined Analysis
  89. GRB 070126?: Swift detection of a possible burst
  90. IPN-BAT localization of GRB070125 (very long duration, intense)
  91. IPN localization of GRB070124 (short duration, hard spectrum)
  92. Swift-BAT trigger 257213 is a Galactic Center transient
  93. GRB 070110: Continued Detection and Request for Ground Followup
  94. GRB 070110: Ep,i - Eiso correlation
  95. GRB 070110 declared a "Burst of Interest" by Swift team
  96. Further Retractions of previous Swift-BAT triggers
  97. Swift-BAT Trigger 255685 is not a GRB
  98. Trigger 255685: Swift detection of a possible burst
  99. GRB 070110: UVOT Observations of a Candidate Afterglow
  100. GRB070110: Swift XRT Team refined analysis

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