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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').

17956 results found.

  1. VLA observation of GRB 070311
  2. GRB 070309: variability of the XRT afterglow candidate
  3. GRB 070311: Swift/UVOT Upper Limits
  4. GRB 070311: Swift-XRT refined analysis
  5. GRB070309: Swift/XRT possible afterglow detection
  6. GRB 070125: Chandra X-ray Confirmation of Jet Break
  7. GRB 070309: Swift/UVOT Upper Limits
  8. Swift UVOT Finding Charts for GRB 070309
  9. GRB 070125: X-ray light curve analysis
  10. VLA observation of GRB 070306
  11. GRB 070306: NOT observations
  12. GRB 070306 Swift/UVOT refined analysis
  13. GRB 070306, Swift-BAT refined analysis
  14. GRB 070306: XRT Team Refined Analysis
  15. GRB070306 - SDSS Pre-burst Observations
  16. GRB 070306: Swift detection of a burst
  17. GRB070227: Swift-XRT refined analysis
  18. GRB 070125, deep late-time optical observation
  19. VLA observation of GRB 070224
  20. GRB 070227: optical observations
  21. GRB 070223: Optical Observations
  22. GRB 070227: optical observations
  23. GRB 070227: Swift/UVOT Upper Limits
  24. GRB 070227: TAROT La Silla observatory optical observations
  25. GRB 070227, Swift-BAT refined analysis
  26. GRB070227: possible X-ray afterglow detection
  27. GRB 070227: Swift detection of a burst in ground analysis
  28. GRB 070224: Optical afterglow confirmation
  29. GRB 070224: Swift/UVOT Upper Limits
  30. GRB070224: Swift-XRT Astrometrically Corrected Position
  31. VLA observation of GRB 070223
  32. VLA observation of GRB 070220
  33. GRB070224: Magellan Imaging Observations
  34. GRB070224: Gemini Imaging Observations
  35. GRB 070224: SARA upper limit
  36. GRB070224: Swift-XRT Refined Analysis
  37. GRB 070224, Swift-BAT refined analysis
  38. GRB 070224: MASTER-Net refind analysis
  39. GRB 070224: MASTER-VWF-Kislovodsk observations
  40. GRB 070224: Swift detection of a burst
  41. GRB070223: Swift/UVOT refined analysis
  42. GRB 070223, Swift-BAT refined analysis
  43. GRB070223: MASTER-VWF-Kislovodsk observations
  44. GRB 070223: Swift-XRT Refined Analysis
  45. GRB 070220: pseudo-z~2.15 from spectral parameters of the prompt
  46. GRB 070223: MDM Observations
  47. GRB070223: Swift burst
  48. Konus-Wind and Konus-A observations of GRB 070220
  49. GRB 070220 Swift-BAT Refined Analysis
  50. Swift/UVOT refined analysis of GRB070220
  51. GRB 070209: Swift XRT refined analysis
  52. GRB 070220: Swift-XRT Refined Analysis
  53. GRB 070220: Swift detection of a burst
  54. GRB070219: MASTER-VWF-Kislovodsk observations
  55. GRB 070219: XRT Refined Analysis
  56. GRB 070219: Swift/UVOT Upper limits
  57. GRB 070219, Swift-BAT refined analysis
  58. GRB 070219: ROTSE-III Optical Limits
  59. GRB070219 - SDSS Pre-Burst Observations
  60. GRB 070219: Swift detection of a burst
  61. Swift-BAT trigger 260304 is NOT a burst or transient
  62. GRB 070209: Swift XRT analysis
  63. GRB 070208: MARGE Optical Observations
  64. IPN localization of very bright long hard GRB 070207
  65. IPN localization of very intense short GRB 070201
  66. GRB 070209, Swift-BAT refined analysis of the short hard burst
  67. GRB 070209: Swift detection of a short hard burst
  68. GRB 070208: Swift XRT refined analysis
  69. GRB 070208: RAPTOR detection of early afterglow onset
  70. GRB 070208: MDM Optical Decay
  71. GRB 070208, Swift-BAT refined analysis
  72. GRB070208: Faulkes Telescope North Afterglow Identification
  73. GRB 070208: ROTSE-III Optical Limits
  74. GRB 070208: MDM Observations
  75. GRB 070208: Swift detection of a burst
  76. Swift-BAT trigger 259527 is a Cosmic Ray Shower
  77. GRB070124: Swift-XRT Follow-up Observation
  78. GRB070126: Swift-XRT Observation
  79. GRB 070129: Swift/UVOT Upper limits
  80. GRB 070129: dust-scattered X-ray halo detected by Swift/XRT
  81. GRB061217: MAGIC telescope GeV observation
  82. GRB 070129, Swift-BAT refined analysis of a particularly long
  83. GRB 070129: Swift-XRT Refined Analysis
  84. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  85. GRB 070129: Swift detection of a burst
  86. GRB 070126: Swift/UVOT refined analysis
  87. GRB070126: Swift-XRT possible detection of an afterglow
  88. GRB 070125: UVOT Detection in Ultraviolet Filters
  89. GRB 070126, Swift-BAT refined analysis of a very faint burst
  90. GRB070124: Swift-XRT Observation
  91. Possible GRB 070126: Swift/UVOT Upper Limit
  92. GRB 070125: UVOT Observations of a Fading Optical Afterglow
  93. GRB 070125: pseudo-z~1.5 from spectral parameters of the prompt emission
  94. GRB070125: Swift-XRT Refined Analysis
  95. GRB 070126?: Swift detection of a possible burst
  96. IPN-BAT localization of GRB070125 (very long duration, intense)
  97. IPN localization of GRB070124 (short duration, hard spectrum)
  98. Swift-BAT trigger 257213 is a Galactic Center transient
  99. GRB 070110: Continued Detection and Request for Ground Followup
  100. GRB 070110: Ep,i - Eiso correlation

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