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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"

18634 results found.

  1. GRB 070227: optical observations
  2. GRB 070227: Swift/UVOT Upper Limits
  3. GRB 070227: TAROT La Silla observatory optical observations
  4. GRB 070227, Swift-BAT refined analysis
  5. GRB070227: possible X-ray afterglow detection
  6. GRB 070227: Swift detection of a burst in ground analysis
  7. GRB 070224: Optical afterglow confirmation
  8. GRB 070224: Swift/UVOT Upper Limits
  9. GRB070224: Swift-XRT Astrometrically Corrected Position
  10. VLA observation of GRB 070223
  11. VLA observation of GRB 070220
  12. GRB070224: Magellan Imaging Observations
  13. GRB070224: Gemini Imaging Observations
  14. GRB 070224: SARA upper limit
  15. GRB070224: Swift-XRT Refined Analysis
  16. GRB 070224, Swift-BAT refined analysis
  17. GRB 070224: MASTER-Net refind analysis
  18. GRB 070224: MASTER-VWF-Kislovodsk observations
  19. GRB 070224: Swift detection of a burst
  20. GRB070223: Swift/UVOT refined analysis
  21. GRB 070223, Swift-BAT refined analysis
  22. GRB070223: MASTER-VWF-Kislovodsk observations
  23. GRB 070223: Swift-XRT Refined Analysis
  24. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  25. GRB 070223: MDM Observations
  26. GRB070223: Swift burst
  27. Konus-Wind and Konus-A observations of GRB 070220
  28. GRB 070220 Swift-BAT Refined Analysis
  29. Swift/UVOT refined analysis of GRB070220
  30. GRB 070209: Swift XRT refined analysis
  31. GRB 070220: Swift-XRT Refined Analysis
  32. GRB 070220: Swift detection of a burst
  33. GRB070219: MASTER-VWF-Kislovodsk observations
  34. GRB 070219: XRT Refined Analysis
  35. GRB 070219: Swift/UVOT Upper limits
  36. GRB 070219, Swift-BAT refined analysis
  37. GRB 070219: ROTSE-III Optical Limits
  38. GRB070219 - SDSS Pre-Burst Observations
  39. GRB 070219: Swift detection of a burst
  40. Swift-BAT trigger 260304 is NOT a burst or transient
  41. GRB 070209: Swift XRT analysis
  42. GRB 070208: MARGE Optical Observations
  43. IPN localization of very bright long hard GRB 070207
  44. IPN localization of very intense short GRB 070201
  45. GRB 070209, Swift-BAT refined analysis of the short hard burst
  46. GRB 070209: Swift detection of a short hard burst
  47. GRB 070208: Swift XRT refined analysis
  48. GRB 070208: RAPTOR detection of early afterglow onset
  49. GRB 070208: MDM Optical Decay
  50. GRB 070208, Swift-BAT refined analysis
  51. GRB070208: Faulkes Telescope North Afterglow Identification
  52. GRB 070208: ROTSE-III Optical Limits
  53. GRB 070208: MDM Observations
  54. GRB 070208: Swift detection of a burst
  55. Swift-BAT trigger 259527 is a Cosmic Ray Shower
  56. GRB070124: Swift-XRT Follow-up Observation
  57. GRB070126: Swift-XRT Observation
  58. GRB 070129: Swift/UVOT Upper limits
  59. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  60. GRB061217: MAGIC telescope GeV observation
  61. GRB 070129, Swift-BAT refined analysis of a particularly long
  62. GRB 070129: Swift-XRT Refined Analysis
  63. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  64. GRB 070129: Swift detection of a burst
  65. GRB 070126: Swift/UVOT refined analysis
  66. GRB070126: Swift-XRT possible detection of an afterglow
  67. GRB 070125: UVOT Detection in Ultraviolet Filters
  68. GRB 070126, Swift-BAT refined analysis of a very faint burst
  69. GRB070124: Swift-XRT Observation
  70. Possible GRB 070126: Swift/UVOT Upper Limit
  71. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  72. GRB 070125: pseudo-z~1.5 from spectral parameters of the prompt emission
  73. GRB070125: Swift-XRT Refined Analysis
  74. GRB 070126?: Swift detection of a possible burst
  75. IPN-BAT localization of GRB070125 (very long duration, intense)
  76. IPN localization of GRB070124 (short duration, hard spectrum)
  77. Swift-BAT trigger 257213 is a Galactic Center transient
  78. GRB 070110: Continued Detection and Request for Ground Followup
  79. GRB 070110: Ep,i - Eiso correlation
  80. GRB 070110 declared a "Burst of Interest" by Swift team
  81. Further Retractions of previous Swift-BAT triggers
  82. Swift-BAT Trigger 255685 is not a GRB
  83. Trigger 255685: Swift detection of a possible burst
  84. GRB 070110: UVOT Observations of a Candidate Afterglow
  85. GRB070110: Swift XRT Team refined analysis
  86. GRB 070110, Swift-BAT refined analysis
  87. GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
  88. GRB 070110: Swift detection of a burst with a possible optical afterglow
  89. GRB070107: Swift/XRT refined analysis
  90. GRB 070107: Possible UVOT Afterglow
  91. GRB 070107, Swift-BAT refined analysis
  92. GRB 070107: Swift/XRT position
  93. GRB 070107: Swift detection of a burst
  94. GRB070103: APO SPIcam i' and z' limits
  95. GRB 070103: Swift/UVOT Upper limits
  96. GRB070103: Swift XRT refined analysis
  97. GRB 070103, Swift-BAT refined analysis
  98. GRB 070103: TAROT Calern observatory optical observations
  99. GRB 070103: Swift detection of a burst
  100. Retractions of previous Swift-BAT triggers

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