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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"

28062 results found.

  1. GRB 100427A: Swift XRT and UVOT Upper Limits
  2. GRB 100427A: Fermi GBM detection
  3. GRB 100414A : EVLA Radio Detection
  4. GRB 100414A : WSRT Radio Detection
  5. GRB 100423A: CrAO optical observations
  6. GRB 100418A: Terskol optical observations
  7. GRB 100424A: CrAO optical observations
  8. GRB 100424A: NIR Afterglow Confirmation
  9. GRB 100425A: Swift XRT refined analysis
  10. GRB 100424A: Gemini/NIRI H-band observations
  11. GRB100425A: Swift/UVOT Upper Limits
  12. GRB 100424A: Swift/UVOT Upper Limits
  13. GRB 100424A: Liverpool Telescope Upper Limits
  14. GRB 100425A: Enhanced Swift-XRT position
  15. GRB 100425A: Swift-BAT refined analysis
  16. GRB 100425A: GROND afterglow observation
  17. GRB 100424A: Gemini/NIRI Candidate Afterglow
  18. GRB 100424A: D50 optical limits
  19. GRB 100425A: candidate optical afterglow from the VLT
  20. GRB100424A: MITSuME optical upper limits
  21. GRB100423A: MITSuME optical upper limits
  22. GRB 100424A : Lulin early z'-band upper limit
  23. GRB 100424A: GROND Upper Limits
  24. GRB 100424A: PAIRITEL NIR Upper Limits
  25. GRB 100424A: Swift-XRT refined analysis
  26. GRB 100425A: Swift detection of a burst
  27. GRB 100424A: NOT optical observations
  28. GRB 100424A, Swift-BAT refined analysis
  29. GRB 100424A: Enhanced Swift-XRT position
  30. GRB 100424A: Prompt enhanced Swift-XRT position.
  31. GRB 100424A: Swift detection of a burst
  32. GRB 100420A: GRT Optical Observation
  33. Swift Trigger 420256: D50 optical limits
  34. GRB 100423B: Fermi GBM detection
  35. GRB 100423A: Swift-BAT refined analysis
  36. Swift Trigger 420256: IAC80 R-band observations
  37. Swift Trigger 420256: BOOTES-2 observations
  38. Trigger 420256: Swift detection of a possible GRB
  39. GRB 100423A: GROND discovery of afterglow
  40. GRB 100418A: Continued PAIRITEL NIR Observations
  41. GRB100418A: REM possible afterglow detection
  42. GRB 100418A: Continuing Swift/UVOT Observations
  43. GRB100420A: MITSuME optical upper limits
  44. GRB 100414A: CFHT optical observations
  45. GRB 100420A: Swift/UVOT Upper Limits
  46. GRB 100420A: XRT refined analysis
  47. GRB 100420A: Enhanced Swift-XRT position
  48. GRB 100418A: SARA second epoch
  49. GRB 100420A: SARA Upper Limits
  50. GRB 100418A: optical observations
  51. GRB 100414A: Confirmation of the X-ray afterglow
  52. GRB 100418A: SMA submm detection
  53. GRB 100420A: Swift detection of a burst
  54. GRB 100418A PAIRITEL NIR Observations
  55. GRB 100418A: Swift/UVOT Observations
  56. GRB 100418A: Gemini-N redshift confirmation
  57. GRB 100418A: Swift-XRT Refined Analysis
  58. GRB100418A: VLT/X-shooter redshift and photometry
  59. GRB 100418A: SARA observations
  60. GRB 100418A: GROND observations; missing author list added
  61. GRB 100418A: GROND observations
  62. GRB 100418A: Swift-BAT refined analysis
  63. GRB 100418A: Enhanced Swift-XRT position
  64. GRB 100418A: Swift detection of a burst with a possible optical afterglow
  65. GRB 100413A: Radio Afterglow Detection with the EVLA
  66. GRB 100414A: Suzaku WAM observation of the prompt emission
  67. GRB 100414A: Swift/UVOT Observations
  68. GRB 100414A: GROND Detection of the Optical Afterglow
  69. GRB 100414A: Gemini-N candidate and redshift
  70. GRB 100414A: Enhanced Swift-XRT position of candidate afterglow
  71. GRB 100413A: Suzaku WAM observation of the prompt emission
  72. GRB 100414A: Palomar Transient Factory Observations
  73. GRB 100413B: Swift Confirmation of Burst
  74. GRB 100414A: Swift-XRT detection of a possible X-ray afterglow
  75. GRB 100413A: Swift-BAT final refined analysis
  76. GRB 100414A: Fermi GBM detection
  77. GRB100414A: Fermi LAT detection
  78. GRB 100413A: GROND Upper limits
  79. GRB 100413A: Swift/UVOT Upper Limits
  80. Konus-Wind observation of GRB 100413A
  81. GRB 100413A: Faulkes Telescope South observations
  82. GRB 100413A: SARA upper limit
  83. GRB 100413A: Swift-XRT Refined Analysis
  84. GRB 100413A: Swift-BAT initial refined analysis
  85. GRB 100413A: Enhanced Swift-XRT position
  86. GRB 100413A: Swift detection of a burst
  87. Spin down rate and inferred dipole magnetic field of the new soft gamma-ray repeater SGR 1833-0832
  88. Trigger 419015 is probably not a GRB
  89. GRB100401A: GROND Upper Limits
  90. INTEGRAL Alert n. 5995: MASTER-Net optical observations
  91. GRB 100331B: GROND Upper limits
  92. GRB 100401A: Fermi GBM detection
  93. GRB 100401A Burst, possibly short, detected in ground analysis of BAT data
  94. GRB 100331B: BOOTES-3 observations
  95. GRB 100324B: Suzaku WAM observation of the prompt emission
  96. GRB 100331B: Swift/UVOT Upper Limits
  97. GRB 100331B: Swift/XRT possible afterglow candidate
  98. Swift detection of LS V +44 17
  99. GRB 100331B: SuperAGILE Localization of a Long GRB
  100. INTEGRAL trigger 5994 / GRB 100331A: GROND detection of a variable source

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