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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"
  1. GRB 101225A: revised analysis of narrow band imaging
  2. GRB 110319B BAT refined analysis
  3. GRB 110319B: Swift/UVOT Upper Limits
  4. GRB 110318B: Swift/UVOT Upper Limits
  5. GRB 110319B: GROND upper limits
  6. GRB 110319B: Swift-XRT afterglow candidate.
  7. GRB 110319B found in ground analysis of Swift-BAT data
  8. GRB 110319A: Swift/UVOT Detection
  9. GRB 110319A: Swift-BAT refined analysis
  10. GRB 110319A: Swift-XRT refined Analysis
  11. GRB 110318B: GROND upper limits
  12. GRB 110319A: Enhanced Swift-XRT position
  13. GRB 110319A: Swift detection of a burst
  14. GRB 110318B: Swift-XRT refined Analysis
  15. GRB 110318A: Fermi GBM detection
  16. GRB 110318B: Swift-BAT refined analysis
  17. GRB 110318B: Enhanced Swift-XRT position
  18. GRB 110318A: Swift-BAT refined analysis
  19. GRB 110318B: Swift/UVOT Non-Detection of an Afterglow
  20. GRB 110318B: Swift detection of a burst
  21. GRB 110318A: Swift detection of a burst
  22. Fermi GBM trigger 321944155 (110316205) is not a GRB
  23. GRB 110315A: RTT150 optical observations
  24. GRB 110315A: Swift/UVOT Upper Limits
  25. GRB 110315A: Swift-XRT refined Analysis
  26. GRB 110315A: Swift-BAT refined analysis
  27. GRB 110315A: Enhanced Swift-XRT position
  28. GRB 110315A: MASTER early optical observations
  29. GRB 110315A: Swift detection of a burst
  30. GRB110312A: MITSuME Okayama Optical upper limits
  31. GRB 110312A: RTT150 optical observations
  32. GRB 110312A: Swift/UVOT Upper Limits
  33. GRB 110312A: Swift-XRT refined Analysis
  34. GRB 110312A: GROND Upper Limits
  35. GRB 110312A: Enhanced Swift-XRT position
  36. GRB 110312A: Swift-BAT refined analysis
  37. GRB 110312A: Swift detection of a burst
  38. GRB 110305A: REM detection of a possible NIR afterglow
  39. GRB110305A: MITSuME Ishigakijima Optical upper limits
  40. GRB 110305A: Swift/UVOT Upper Limits
  41. GRB 110305A: Swift-XRT refined Analysis
  42. GRB 110305A: Enhanced Swift-XRT position
  43. GRB 110305A: Swift-BAT refined analysis
  44. IBAS trigger n. 6138 is not a GRB
  45. GRB 110305A: GROND Detection of Optical Afterglow
  46. GRB 110305A: Swift detection of a burst
  47. GRB 110223A: optical upper limits
  48. GRB 110301A: Fermi GBM detection
  49. GRB101225A: early EVLA Observations of Christmas Burst
  50. Swift/UVOT observations of GRB110223A
  51. No IPN GRB detected in conjunction with candidate GRB 110215
  52. GRB GRB 110223A: MASTER VWF early optical observations
  53. IBAS distribution of coordinates for low significance INTEGRAL GRB triggers
  54. Swift/UVOT observations of GRB110223b
  55. GRB 110223A: Swift-BAT refined analysis
  56. GRB 110223A : early optical limit by "Pi of the Sky"
  57. GRB 110223A: Liverpool Telescope observations
  58. GRB 110223A: Swift-XRT refined Analysis
  59. GRB 110223B: Swift-XRT refined Analysis
  60. GRB 110223A: Enhanced Swift-XRT position
  61. GRB 110223B: Enhanced Swift-XRT position
  62. GRB 110223B: Swift-BAT refined analysis
  63. GRB 110223B: GROND Detection of Optical Afterglow Candidate
  64. GRB 110223A: Observations from BOOTES-2
  65. GRB 110223B: Swift detection of a burst
  66. GRB 110223A: Swift detection of a burst
  67. GRB 101225A, the review of the sky area in plate archives
  68. OT 110215: Further NIR observations from NOT of the GRB candidate
  69. GRB 110213B: Swift/UVOT observations
  70. GRB110213B: X-ray afterglow confirmation
  71. Fermi GBM detection of an SGR-like burst
  72. Swift XRT and UVOT Observations of OT 110215
  73. OT 110215: NIR observations from NOT of GRB candidate
  74. GRB 110213A: optical observations in CrAO
  75. GRB 110213B: GROND observations of the optical/NIR afterglow
  76. GRB 110213A: optical observations in Mondy
  77. Fermi GBM trigger 319534757 (110216319) is not a GRB
  78. GRB110205A: EVLA Observations
  79. OT 110215: possible GRB from 2MASS J00264184+8324093
  80. Swift/UVOT observations of GRB110210a.
  81. GRB 110210A: optical upper limit
  82. GRB 110213B: Gemini South Redshift
  83. GRB 110213B: Possible Host Galaxy in SDSS Stripe 82 Imaging
  84. GRB 110210A: ROVOR Upper Limit
  85. GRB 110213A: YNAO-GMG Observations
  86. GRB 110213B: P60 Optical Afterglow Candidate
  87. GRB 110213A: TNT optical observations
  88. GRB110213A: RAPTOR Early Optical Peak and Plateau Measurements
  89. GRB 110212A: Swift XRT and UVOT observations
  90. Swift GRB110213A: interesting behaviour
  91. GRB 110213A: Fermi GBM observation
  92. GRB 110205A: Konkoly optical observations
  93. GRB 110213B: Swift XRT observation
  94. GRB 110213A: MITSuME Akeno Optical Observation
  95. Konus-Wind observation of GRB 110213A
  96. Konus-Wind observation of GRB 110213B
  97. GRB 110213A: Swift-XRT refined Analysis
  98. GRB 110213B: MAXI/GSC refined analysis
  99. GRB110213A: MITSuME Okayama Optical Observation
  100. GRB 110213A: Swift/UVOT refined analysis

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