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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"

28056 results found.

  1. GRB 070318, Swift-BAT refined analysis
  2. GRB 070318: Swift detection of a burst with an optical afterglow
  3. GRB 070311: Late Central Engine Activity Optical Flare??
  4. VLA observation of GRB 070311
  5. GRB 070311: Optical observation.
  6. GRB 070306: possible emission-line redshift
  7. GRB 070311: SARA upper limit
  8. GRB 070309: variability of the XRT afterglow candidate
  9. GRB070311: FRAM early follow-up limit
  10. GRB 070311: P60 Observations
  11. GRB 070311: Swift/UVOT Upper Limits
  12. GRB 070311: MITSuME Okayama Optical Observation
  13. GRB 070311: Swift-XRT refined analysis
  14. GRB 070311: PAIRITEL confirmation of variability of REM candidate
  15. GRB 070311: REM candidate afterglow
  16. GRB 070311: a long GRB detected by INTEGRAL
  17. GRB060901: Candidate optical afterglow
  18. GRB 070125: Chandra X-ray Confirmation of Jet Break
  19. GRB 070309: Swift/UVOT Upper Limits
  20. GRB 070306, optical observation
  21. Swift UVOT Finding Charts for GRB 070309
  22. GRB 070309: A long GRB detected by INTEGRAL
  23. GRB 070125: X-ray light curve analysis
  24. VLA observation of GRB 070306
  25. GRB 070306: NOT observations
  26. GRB 070306 Swift/UVOT refined analysis
  27. GRB 070306: IR observations and candidate afterglow
  28. GRB 070306, Swift-BAT refined analysis
  29. GRB 070306: XRT Team Refined Analysis
  30. GRB 070306: Optical and IR observations with KANATA
  31. GRB070306 - SDSS Pre-burst Observations
  32. GRB 070306: Swift detection of a burst
  33. GRB070227: Swift-XRT refined analysis
  34. GRB 060605 new redshift
  35. GRB 070125, deep late-time optical observation
  36. VLA observation of GRB 070224
  37. GRB 070227: Swift/UVOT Upper Limits
  38. GRB 070227: TAROT La Silla observatory optical observations
  39. GRB 070227, Swift-BAT refined analysis
  40. GRB 070227: Swift detection of a burst in ground analysis
  41. GRB 070224: Swift/UVOT Upper Limits
  42. VLA observation of GRB 070223
  43. VLA observation of GRB 070220
  44. GRB070224: Magellan Imaging Observations
  45. GRB 070224: WHT K-band imaging
  46. GRB 070224: MDM Observations
  47. GRB070224: Gemini Imaging Observations
  48. GRB 070224: SARA upper limit
  49. GRB070224: Swift-XRT Refined Analysis
  50. GRB 070224: optical afterglow candidate
  51. GRB 070224, Swift-BAT refined analysis
  52. GRB 070224: MASTER-Net refind analysis
  53. GRB 070224: MASTER-VWF-Kislovodsk observations
  54. GRB 070224: Swift detection of a burst
  55. GRB 070223: Optical observations
  56. GRB070223: Swift/UVOT refined analysis
  57. GRB 070223: Optical-IR observation with KANATA
  58. GRB 070223, Swift-BAT refined analysis
  59. GRB070223: MASTER-VWF-Kislovodsk observations
  60. GRB 070223: Swift-XRT Refined Analysis
  61. GRB070223 - SDSS Pre-Burst Observations
  62. GRB 070223: MDM Observations
  63. GRB070223: Swift burst
  64. GRB 070220: MITSuME Okayama Optical Observation
  65. GRB 070220 Swift-BAT Refined Analysis
  66. Swift/UVOT refined analysis of GRB070220
  67. GRB 070209: Swift XRT refined analysis
  68. GRB 070220: Swift-XRT Refined Analysis
  69. GRB 070220: Observation with the KANATA 1.5m telescope
  70. GRB 070219: Gemini Observations
  71. GRB 070220: Swift detection of a burst
  72. GRB070219: MASTER-VWF-Kislovodsk observations
  73. GRB 070219: Swift/UVOT Upper limits
  74. GRB 070219: I-band observations
  75. GRB 070219, Swift-BAT refined analysis
  76. GRB 070219: optical TNG observations
  77. GRB070219 - SDSS Pre-Burst Observations
  78. GRB 070219: Swift detection of a burst
  79. GRB 070125 observations with the GMRT
  80. GRB 070209: Redshift of a galaxy in the error circle of XRT source
  81. GRB 070129: MDM I-band Detection
  82. GRB 070125: Break in Optical Decay
  83. GRB 070209: Swift XRT analysis
  84. GRB 070201: clarification on localization and Konus-Wind spectra
  85. IPN localization of very bright long hard GRB 070207
  86. GRB 070209, Swift-BAT refined analysis of the short hard burst
  87. GRB 070208: Swift XRT refined analysis
  88. GRB 070208, Swift-BAT refined analysis
  89. GRB070208 - SDSS Pre-Burst Observations
  90. GRB 070208: Early IR detection and afterglow astrometry
  91. GRB 070208: Swift detection of a burst
  92. GRB 070125 detection with CARMA
  93. GRB 070125: Redshift z>~1.54 from Gemini Afterglow Spectrum
  94. GRB 070129: afterglow confirmation
  95. GRB070126: Swift-XRT Observation
  96. GRB 070129: Swift/UVOT Upper limits
  97. GRB 070125: optical observation
  98. GRB 070129, Swift-BAT refined analysis of a particularly long
  99. GRB 070129: Xinglong TNT optical Upper Limit
  100. GRB 070129: Swift-XRT Refined Analysis

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