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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"

28053 results found.

  1. GRB 100814A: NOT optical observations
  2. GRB 100816A: NOT optical observations
  3. GRB 100814A : Lulin optical observation
  4. GRB 100816A : Lulin r'-band observation
  5. GRB 100816A: Swift UVOT Observations
  6. GRB100816A Swift-XRT refined analysis
  7. GRB 100816A: Swift-BAT spectral lag results
  8. GRB 100816A: 1.23m CAHA optical observations
  9. GRB 100816A, Swift-BAT refined analysis
  10. GRB 100816A: Enhanced Swift-XRT position
  11. GRB 100816A: Gemini-N imaging
  12. GRB 100816A: TAROT Calern observatory optical detection
  13. GRB 100816A: MASTER Optical Limits
  14. GRB100816A: TNG optical afterglow confirmation.
  15. GRB 100816A: Swift detection of a possibly short burst with optical afterglow
  16. GRB 100814A: Fermi GBM observation
  17. GRB 100814A: Submm observations from APEX
  18. GRB 100814A: Swift-XRT refined analysis
  19. Swift/UVOT observations of GRB100814A
  20. GRB 100814A, Swift-BAT refined analysis
  21. GRB 100814A: Enhanced Swift-XRT position
  22. GRB 100814A: GROND Detection of the Optical/NIR Afterglow
  23. GRB 100814A: Swift UVOT observations of the optical afterglow
  24. GRB 100814A: Swift detection of a burst with an optical afterglow
  25. GRB 100814A: ROTSE-III Detection of Optical Counterpart
  26. GRB 100805A: the 4-th epoch of SAO RAS optical observations
  27. GRB 100805A: optical observation in CrAO (correction to the GCN 11077 and second epoch)
  28. GRB 100802A: further NOT observation
  29. GRB 100805A: Swift/UVOT Observations of a Possible Late-Time Brightening
  30. GRB 100807A: P200 Infrared Observations
  31. GRB 100805A: the 3-rd epoch of SAO RAS optical observations
  32. GRB100807A: optical observation in CrAO
  33. GRB 100805A: optical observation in CrAO
  34. GRB 100805A: 2-nd epoch of SAO RAS optical observations
  35. GRB100807A: MITSuME optical upper limits
  36. GRB 100807A: Swift XRT refined analysis
  37. GRB 100807A: P60 Optical Afterglow Discovery
  38. GRB 100807A: Swift/UVOT Upper Limits
  39. GRB 100805A: SAO RAS optical observations
  40. GRB 100807A: Enhanced Swift-XRT position
  41. GRB 100807A: Swift-BAT refined analysis
  42. GRB 100807A: Swift detection of a burst
  43. GRB 100805A: IAC80 and 1.5m OSN optical observations
  44. GRB 100805A: Early RAPTOR Observations
  45. GRB 100805A: Swift/UVOT Observations of the Optical Afterglow
  46. GRB 100802A: WIYN observations
  47. GRB 100805A: IAC80 BVR-band observations
  48. GRB 100805A: Swift-BAT refined analysis
  49. GRB 100805A: Swift-XRT Refined Analysis
  50. GRB 100805A: GRAS 002 optical observations
  51. Trigger 430975: Swift detection of a possible burst
  52. GRB 100805A: I-band detection from 1.23m CAHA telescope.
  53. GRB 100805A: Enhanced Swift-XRT position
  54. GRB 100805A: Further P60 Monitoring
  55. GRB 100805A: P60 Optical Afterglow Candidate
  56. GRB 100805A: Swift detection of a burst with an optical counterpart
  57. GRB 100802A: Fermi GBM observation
  58. GRB 100728B: optical photometry of ISON-NM
  59. GRB 100713A: second epoch Maidanak optical observation
  60. GRB 100713A: CrAO optical limits
  61. GRB 100802A: NOT optical observation
  62. GRB100802A: MITSuME optical upper limits
  63. GRB 100802A: P60 Observations
  64. GRB 100802A: XRT refined analysis
  65. GRB 100802A: Swift/UVOT Possible Optical Afterglow
  66. GRB 100728A: Suzaku WAM observation of the prompt emission
  67. GRB 100802A: Enhanced Swift-XRT position
  68. GRB 100802A: Swift-BAT refined analysis
  69. GRB 100802A: Possible Swift/UVOT Detection of Optical Afterglow
  70. GRB 100802A: Swift detection of a burst
  71. GRB 100728B - NOT optical observation
  72. GRB 100728B: Swift/UVOT Observations
  73. GRB 100728B: Continued KAIT observations
  74. GRB 100728B, Swift-BAT refined analysis
  75. GRB 100728B: Swift-XRT Refined Analysis
  76. GRB 100728A: GROND Detection of the NIR Afterglow Candidate
  77. GRB 100727A: Swift/UVOT Upper Limits
  78. GRB 100728A, Swift-BAT refined analysis
  79. GRB 100728B: Enhanced Swift-XRT position
  80. GRB 100728A: Swift/UVOT Upper Limits
  81. GRB 100728A: Swift-XRT refined analysis
  82. GRB 100728B: GROND Detection of the NIR Afterglow
  83. GRB 100728B: optical detection
  84. GRB 100728B: Swift detection of a burst with an optical counterpart
  85. GRB 100728A: Enhanced Swift-XRT position
  86. GRB 100728A: Swift detection of a burst
  87. GRB 100727A: Swift XRT refined analysis
  88. GRB 100727A, Swift-BAT refined analysis
  89. GRB 100727A: Enhanced Swift-XRT position
  90. GRB 100727A: Swift detection of a burst
  91. GRB100725B: MITSuME optical upper limits
  92. GRB 100724B: AGILE/GRID analysis
  93. GRB 100724B: Suzaku WAM observation of the prompt emission
  94. GRB 100724B: gamma-ray detection by AGILE
  95. GRB 100725B: Swift-BAT refined analysis
  96. GRB 100725B: refined XRT analysis
  97. GRB 100725A: GROND upper limits
  98. GRB 100725B: Swift/UVOT Upper Limits
  99. GRB 100725A: Swift/UVOT Upper Limits
  100. GRB 100725A: Swift-BAT refined analysis

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