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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').

18341 results found.

  1. GRB 070306: Swift detection of a burst
  2. GRB070227: Swift-XRT refined analysis
  3. GRB 070125, deep late-time optical observation
  4. VLA observation of GRB 070224
  5. GRB 070227: optical observations
  6. GRB 070223: Optical Observations
  7. GRB 070227: optical observations
  8. GRB 070227: Swift/UVOT Upper Limits
  9. GRB 070227: TAROT La Silla observatory optical observations
  10. GRB 070227, Swift-BAT refined analysis
  11. GRB070227: possible X-ray afterglow detection
  12. GRB 070227: Swift detection of a burst in ground analysis
  13. GRB 070224: Optical afterglow confirmation
  14. GRB 070224: Swift/UVOT Upper Limits
  15. GRB070224: Swift-XRT Astrometrically Corrected Position
  16. VLA observation of GRB 070223
  17. VLA observation of GRB 070220
  18. GRB070224: Magellan Imaging Observations
  19. GRB070224: Gemini Imaging Observations
  20. GRB 070224: SARA upper limit
  21. GRB070224: Swift-XRT Refined Analysis
  22. GRB 070224, Swift-BAT refined analysis
  23. GRB 070224: MASTER-Net refind analysis
  24. GRB 070224: MASTER-VWF-Kislovodsk observations
  25. GRB 070224: Swift detection of a burst
  26. GRB070223: Swift/UVOT refined analysis
  27. GRB 070223, Swift-BAT refined analysis
  28. GRB070223: MASTER-VWF-Kislovodsk observations
  29. GRB 070223: Swift-XRT Refined Analysis
  30. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  31. GRB 070223: MDM Observations
  32. GRB070223: Swift burst
  33. Konus-Wind and Konus-A observations of GRB 070220
  34. GRB 070220 Swift-BAT Refined Analysis
  35. Swift/UVOT refined analysis of GRB070220
  36. GRB 070209: Swift XRT refined analysis
  37. GRB 070220: Swift-XRT Refined Analysis
  38. GRB 070220: Swift detection of a burst
  39. GRB070219: MASTER-VWF-Kislovodsk observations
  40. GRB 070219: XRT Refined Analysis
  41. GRB 070219: Swift/UVOT Upper limits
  42. GRB 070219, Swift-BAT refined analysis
  43. GRB 070219: ROTSE-III Optical Limits
  44. GRB070219 - SDSS Pre-Burst Observations
  45. GRB 070219: Swift detection of a burst
  46. Swift-BAT trigger 260304 is NOT a burst or transient
  47. GRB 070209: Swift XRT analysis
  48. GRB 070208: MARGE Optical Observations
  49. IPN localization of very bright long hard GRB 070207
  50. IPN localization of very intense short GRB 070201
  51. GRB 070209, Swift-BAT refined analysis of the short hard burst
  52. GRB 070209: Swift detection of a short hard burst
  53. GRB 070208: Swift XRT refined analysis
  54. GRB 070208: RAPTOR detection of early afterglow onset
  55. GRB 070208: MDM Optical Decay
  56. GRB 070208, Swift-BAT refined analysis
  57. GRB070208: Faulkes Telescope North Afterglow Identification
  58. GRB 070208: ROTSE-III Optical Limits
  59. GRB 070208: MDM Observations
  60. GRB 070208: Swift detection of a burst
  61. Swift-BAT trigger 259527 is a Cosmic Ray Shower
  62. GRB070124: Swift-XRT Follow-up Observation
  63. GRB070126: Swift-XRT Observation
  64. GRB 070129: Swift/UVOT Upper limits
  65. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  66. GRB061217: MAGIC telescope GeV observation
  67. GRB 070129, Swift-BAT refined analysis of a particularly long
  68. GRB 070129: Swift-XRT Refined Analysis
  69. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  70. GRB 070129: Swift detection of a burst
  71. GRB 070126: Swift/UVOT refined analysis
  72. GRB070126: Swift-XRT possible detection of an afterglow
  73. GRB 070125: UVOT Detection in Ultraviolet Filters
  74. GRB 070126, Swift-BAT refined analysis of a very faint burst
  75. GRB070124: Swift-XRT Observation
  76. Possible GRB 070126: Swift/UVOT Upper Limit
  77. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  78. GRB 070125: pseudo-z~1.5 from spectral parameters of the prompt emission
  79. GRB070125: Swift-XRT Refined Analysis
  80. GRB 070126?: Swift detection of a possible burst
  81. IPN-BAT localization of GRB070125 (very long duration, intense)
  82. IPN localization of GRB070124 (short duration, hard spectrum)
  83. Swift-BAT trigger 257213 is a Galactic Center transient
  84. GRB 070110: Continued Detection and Request for Ground Followup
  85. GRB 070110: Ep,i - Eiso correlation
  86. GRB 070110 declared a "Burst of Interest" by Swift team
  87. Further Retractions of previous Swift-BAT triggers
  88. Swift-BAT Trigger 255685 is not a GRB
  89. Trigger 255685: Swift detection of a possible burst
  90. GRB 070110: UVOT Observations of a Candidate Afterglow
  91. GRB070110: Swift XRT Team refined analysis
  92. GRB 070110, Swift-BAT refined analysis
  93. GRB070107 Swift/UVOT Observations of a Fading Optical Afterglow
  94. GRB 070110: Swift detection of a burst with a possible optical afterglow
  95. GRB070107: Swift/XRT refined analysis
  96. GRB 070107: Possible UVOT Afterglow
  97. GRB 070107, Swift-BAT refined analysis
  98. GRB 070107: Swift/XRT position
  99. GRB 070107: Swift detection of a burst
  100. GRB070103: APO SPIcam i' and z' limits

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