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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"

25043 results found.

  1. GRB 070311: PAIRITEL confirmation of variability of REM candidate
  2. GRB 070311: REM candidate afterglow
  3. GRB 070311: a long GRB detected by INTEGRAL
  4. GRB060901: Candidate optical afterglow
  5. GRB 070125: Chandra X-ray Confirmation of Jet Break
  6. GRB 070309: Swift/UVOT Upper Limits
  7. GRB 070306, optical observation
  8. Swift UVOT Finding Charts for GRB 070309
  9. GRB 070309: A long GRB detected by INTEGRAL
  10. GRB 070125: X-ray light curve analysis
  11. VLA observation of GRB 070306
  12. GRB 070306: NOT observations
  13. GRB 070306 Swift/UVOT refined analysis
  14. GRB 070306: IR observations and candidate afterglow
  15. GRB 070306, Swift-BAT refined analysis
  16. GRB 070306: XRT Team Refined Analysis
  17. GRB 070306: Optical and IR observations with KANATA
  18. GRB070306 - SDSS Pre-burst Observations
  19. GRB 070306: Swift detection of a burst
  20. GRB070227: Swift-XRT refined analysis
  21. GRB 060605 new redshift
  22. GRB 070125, deep late-time optical observation
  23. VLA observation of GRB 070224
  24. GRB 070227: Swift/UVOT Upper Limits
  25. GRB 070227: TAROT La Silla observatory optical observations
  26. GRB 070227, Swift-BAT refined analysis
  27. GRB 070227: Swift detection of a burst in ground analysis
  28. GRB 070224: Swift/UVOT Upper Limits
  29. VLA observation of GRB 070223
  30. VLA observation of GRB 070220
  31. GRB070224: Magellan Imaging Observations
  32. GRB 070224: WHT K-band imaging
  33. GRB 070224: MDM Observations
  34. GRB070224: Gemini Imaging Observations
  35. GRB 070224: SARA upper limit
  36. GRB070224: Swift-XRT Refined Analysis
  37. GRB 070224: optical afterglow candidate
  38. GRB 070224, Swift-BAT refined analysis
  39. GRB 070224: MASTER-Net refind analysis
  40. GRB 070224: MASTER-VWF-Kislovodsk observations
  41. GRB 070224: Swift detection of a burst
  42. GRB 070223: Optical observations
  43. GRB070223: Swift/UVOT refined analysis
  44. GRB 070223: Optical-IR observation with KANATA
  45. GRB 070223, Swift-BAT refined analysis
  46. GRB070223: MASTER-VWF-Kislovodsk observations
  47. GRB 070223: Swift-XRT Refined Analysis
  48. GRB070223 - SDSS Pre-Burst Observations
  49. GRB 070223: MDM Observations
  50. GRB070223: Swift burst
  51. GRB 070220: MITSuME Okayama Optical Observation
  52. GRB 070220 Swift-BAT Refined Analysis
  53. Swift/UVOT refined analysis of GRB070220
  54. GRB 070209: Swift XRT refined analysis
  55. GRB 070220: Swift-XRT Refined Analysis
  56. GRB 070220: Observation with the KANATA 1.5m telescope
  57. GRB 070219: Gemini Observations
  58. GRB 070220: Swift detection of a burst
  59. GRB070219: MASTER-VWF-Kislovodsk observations
  60. GRB 070219: Swift/UVOT Upper limits
  61. GRB 070219: I-band observations
  62. GRB 070219, Swift-BAT refined analysis
  63. GRB 070219: optical TNG observations
  64. GRB070219 - SDSS Pre-Burst Observations
  65. GRB 070219: Swift detection of a burst
  66. GRB 070125 observations with the GMRT
  67. GRB 070209: Redshift of a galaxy in the error circle of XRT source
  68. GRB 070129: MDM I-band Detection
  69. GRB 070125: Break in Optical Decay
  70. GRB 070209: Swift XRT analysis
  71. GRB 070201: clarification on localization and Konus-Wind spectra
  72. IPN localization of very bright long hard GRB 070207
  73. GRB 070209, Swift-BAT refined analysis of the short hard burst
  74. GRB 070208: Swift XRT refined analysis
  75. GRB 070208, Swift-BAT refined analysis
  76. GRB070208 - SDSS Pre-Burst Observations
  77. GRB 070208: Early IR detection and afterglow astrometry
  78. GRB 070208: Swift detection of a burst
  79. GRB 070125 detection with CARMA
  80. GRB 070125: Redshift z>~1.54 from Gemini Afterglow Spectrum
  81. GRB 070129: afterglow confirmation
  82. GRB070126: Swift-XRT Observation
  83. GRB 070129: Swift/UVOT Upper limits
  84. GRB 070125: optical observation
  85. GRB 070129, Swift-BAT refined analysis of a particularly long
  86. GRB 070129: Xinglong TNT optical Upper Limit
  87. GRB 070129: Swift-XRT Refined Analysis
  88. GRB 070129: VLT observations
  89. GRB 070125: An IR Point Source and an Apparent Host Galaxy
  90. GRB 070129: Swift detection of a burst
  91. GRB 070126: Swift/UVOT refined analysis
  92. GRB 070125: MITSuME Okayama optical observation
  93. GRB 070125: optical observations
  94. GRB 070126: VLT observations
  95. GRB 070124: Suzaku WAM observation of the prompt emissions
  96. GRB 070125: UVOT Detection in Ultraviolet Filters
  97. GRB 070126, Swift-BAT refined analysis of a very faint burst
  98. GRB070125: Optical observation by Kanata
  99. GRB070124: Swift-XRT Observation
  100. Possible GRB 070126: Swift/UVOT Upper Limit

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