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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"

25808 results found.

  1. GRB 080725: REM prompt observations
  2. GRB 080723A: Swift/UVOT Upper Limits
  3. VLA radio upper limit on GRB 080721
  4. GRB 080723B - correction to flux conversion factor
  5. GRB 080723B - Swift-XRT refined analysis
  6. GRB 080723, Swift-BAT refined analysis
  7. GRB 080723B: AGILE GRID and MCAL results
  8. GRB 080723A: Swift-XRT refined analysis
  9. GRB 080723B: Detection and Localization by SuperAGILE
  10. GRB 080723: Enhanced Swift-XRT position
  11. GRB 080723: Swift detection of a burst
  12. GRB 080721 : Lulin 2nd optical follow-ups
  13. GRB 080721: Swift-XRT refined analysis
  14. GRB 080721: Enhanced Swift-XRT position
  15. GRB 080721, Swift-BAT refined analysis
  16. GRB 080721 : Lulin Optical follow-ups
  17. GRB 080721: Swift detection of a burst with a bright optical counterpart.
  18. Trigger 317393: Swift detection of a possible GRB
  19. Trigger 317205: Swift detection of an outburst from XTE J1701-407
  20. GRB 080714: GROND confirmation of the optical/NIR afterglow
  21. Konus-Wind observation of GRB 080714
  22. GRB 080714: Swift/UVOT Detection of an Optical Afterglow
  23. GRB 080714: Enhanced Swift-XRT position
  24. GRB 080714: Swift-BAT refined analysis
  25. GRB 080714: Swift detection of a burst
  26. GRB 080702A: optical upper limit
  27. GRB 080603A: CrAO optical observations
  28. GRB 080702B: Swift XRT confirmation of the afterglow
  29. GRB 080710: Lick IR detection
  30. GRB 080710, Swift-BAT refined analysis
  31. GRB 0800707: optical observations
  32. GRB 080710: Swift-XRT refined analysis
  33. GRB080710: Swift/UVOT observations
  34. GRB 080710: Enhanced Swift-XRT position
  35. UVOT white band observations of GRB080710
  36. GRB 080710: REM afterglow confirmation & brightening
  37. GRB 080710: Swift XRT position
  38. New Swift-XRT GRB products available online.
  39. GRB 080707: GROND Confirmation of the Optical Afterglow
  40. UVOT observations of GRB080707
  41. GRB 080707, Swift-BAT refined analysis
  42. GRB 080707: Swift XRT refined analysis
  43. GRB 080707: Enhanced Swift-XRT position
  44. GRB 080707: VLT redshift
  45. GRB 080707: GROND Detection of the Optical Afterglow Candidate
  46. GRB 080707: Swift detection of a burst
  47. Refined analysis of Swift Trigger 316063, is IGR J08408-4503
  48. Trigger 316063: Swift detection of a transient
  49. GRB 080703: GROND Upper Limits
  50. GRB 080702B: GROND Upper Limits
  51. GRB 080703: UVOT Follow-Up Observation
  52. GRB 080703: VLT observations of the afterglow
  53. GRB 080703: Enhanced Swift-XRT position
  54. GRB 080703, Swift-BAT refined analysis
  55. GRB 080702B Swift-BAT refined analysis
  56. GRB 080703: Swift detection of a burst with optical afterglow
  57. GRB 080703A: ROTSE-III Detection of Optical Counterpart
  58. No radio detection from the short GRB 080702A
  59. Swift/UVOT observation of GRB080702A
  60. GRB 080702B: Swift XRT and UVOT observations
  61. GRB 080625: Suzaku WAM observation of the prompt emission
  62. GRB 080701A: Early RAPTOR optical limits
  63. Swift Trigger 315630: Swift/UVOT Upper Limits
  64. GRB 080702A, Swift-BAT refined analysis
  65. GRB 080702A: Swift-XRT Team refined analysis
  66. GRB 080702B : Burst detected in BAT during Swift slew
  67. GRB 080702A: Enhanced Swift-XRT position
  68. Swift Trigger 315630: TLS R-band observation
  69. Swift Trigger 315630: Probably not a GRB
  70. GRB 080702: Swift detection of a short burst
  71. GRB 080701A, VATT optical upper limit
  72. TLS I-Band Observation of GRB 080701A
  73. GRB 080701A: Swift/UVOT Upper Limits
  74. GRB 080701: Enhanced Swift-XRT position
  75. GRB 080701A, Swift-BAT refined analysis
  76. Trigger 315630: Swift detection of a possible burst
  77. GRB 080701: Swift-XRT Prompt Analysis
  78. GRB 080701: Swift detection of a burst
  79. GRB 080623: Suzaku WAM observation of the prompt emission
  80. GRB 080625: Further observations from OSN
  81. GRB 080625:Swift-XRT detection of the afterglow
  82. GRB 080625: Swift/UVOT Detection of an Optical Afterglow
  83. GRB 080625: Observations at OSN
  84. GRB 080625: Gamma Ray Burst Localization by SuperAGILE
  85. GRB 080623: GROND upper limits
  86. GRB 080623: Swift-XRT refined analysis
  87. GRB 080623, Swift-BAT refined analysis
  88. GRB 080623: Enhanced Swift-XRT position
  89. GRB 080623: TAROT La Silla observatory optical observations
  90. GRB 080623: Swift XRT prompt analysis
  91. Swift trigger 314975 is not a GRB
  92. GRB080607: optical observation
  93. GRB 070809: Putative host galaxy and redshift
  94. VLA upper limit on INTEGRAL burst GRB 080613A
  95. GRB080613B: MITSuME upper limits
  96. GRB080613A: Optical upper limits with Okayama MITSuME telescope
  97. GRB 080603A: optical observations on June 04
  98. GRB 080613A: Swift-XRT detection of the afterglow
  99. GRB 080613A: GROND Confirmation of the Afterglow Candidate
  100. GRB 080613B: GROND Upper Limits

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