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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

38612 results found.

  1. GRB 090618: Correction to GCN 9568
  2. GRB 090617: Suzaku WAM observation of the prompt emission
  3. GRB 090618: Suzaku WAM observation of the prompt emission
  4. GRB 090621A: Enhanced Swift-XRT position
  5. GRB 090623: Fermi GBM detection
  6. GRB 090621B: GRT Optical Observation
  7. GRB 090621A: GRT Optical Observation
  8. PAIRITEL observations of GRB 090618
  9. GRB 090621B: Fermi GBM detection
  10. GRB 090621B: I-band observations from 1.23m CAHA
  11. GRB 090621D: Fermi GBM detection
  12. GRB 090621B: Gemini spectrum of afterglow candidate
  13. GRB 090621C: Fermi GBM detection
  14. GRB 090621B: P60 Observations
  15. GRB 090621: Fermi GBM observation
  16. GRB 090621B: VLA observations
  17. GRB 090620: Fermi GBM detecion
  18. Konus-Wind and Konus-RF observations of GRB 090618
  19. GRB 090621B: Swift/UVOT Upper Limits
  20. GRB 090621B: Swift-XRT refined analysis
  21. GRB 090621B: RTT150 optical observations
  22. GRB 090621B: Swift detection of a short hard burst
  23. GRB 090621: Swift/UVOT Upper Limits
  24. GRB 090621: Swift-XRT Team refined analysis
  25. GRB090618: Spectrum and photometry from 6.0m BTA
  26. GRB 090621: Swift detection of a burst
  27. GRB 090618: ZTSh optical observations
  28. GRB 090618 : WSRT radio detection
  29. GRB090618, underlying supernova search
  30. GRB090618: OAA-OAUV Optical observations
  31. GRB 090618: Fermi GBM observation
  32. VLA radio detection of GRB 090618
  33. GRB 090618 15GHz radio detection
  34. GRB090618 - Continued optical monitoring and light curve break
  35. GRB090618: Swift-XRT team refined analysis
  36. GRB090618: Swift/UVOT bright afterglow detection
  37. Swift XRT observations of GRB 090531A
  38. GRB 090618: AGILE observations
  39. GRB 090617: Fermi GBM detection
  40. GRB 090618: LOAO R-band Observation
  41. GRB 090618: Enhanced Swift-XRT position
  42. GRB 090618 Faulkes Telescope North observations
  43. GRB 090618: Lick/KAST Spectroscopy
  44. GRB 090618: OA behavior from KAIT
  45. GRB 090618: planned XMM-Newton observation
  46. GRB 090618: ROTSE-III Detection of Optical Counterpart
  47. GRB 090618: KAIT optical afterglow
  48. GRB090618: P60 Optical Afterglow
  49. GRB 090618: Swift detection of a bright burst with optical afterglow
  50. GRB 090616: Fermi GBM detection
  51. GRB 090612: Fermi GBM detection
  52. GRB 090610C: Fermi GBM detection
  53. GRB 090610B: Fermi GBM detection
  54. GRB 090610: Fermi GBM detection
  55. GRB 090602: Suzaku WAM observation of the prompt emission
  56. GRB 090424: WSRT Radio Observations
  57. GRB 090423: WSRT Radio Observations
  58. RXTE Discovery of Pulsations from SGR 0418+5729
  59. GRB 090531B: Fermi GBM detection
  60. Konus-RF observation of SGR burst 090605A
  61. Discovery of a new soft gamma repeater source, SGR 0418+5729
  62. GRB 090608: Fermi GBM detection
  63. GRB 090606: Fermi GBM detection
  64. GRB 090607: XRT Team Refined Analysis
  65. GRB 090607: Swift/UVOT Upper Limits
  66. GRB 090607: Swift-BAT refined analysis of the SHB
  67. GRB 090607: GRAS001 optical observations
  68. GRB 090607: Faulkes Telescope North observations
  69. GRB 090607: Swift detection of a burst
  70. GRB 090530B: Suzaku WAM observation of the prompt emission
  71. GRB 090530: Further NOT optical observations
  72. GRB 090530: RTT150 Optical Observation
  73. GRB 090602: Fermi GBM detection
  74. GRB 090529A: RTT150 Optical Observations
  75. GMRT observation of GRB 090424 afterglow
  76. GRB 090528: Suzaku WAM observation of the prompt emission
  77. GRB090529: Further NOT optical observations
  78. GRB 090531b, SMARTS optical/IR observations
  79. GRB 090531B: GROND observation
  80. GRB 090528B: Suzaku WAM observation of the prompt emission
  81. GRB090529B: ROVOR Upper Limits
  82. GRB 090529C: Fermi GBM detection
  83. GRB 090529B: Fermi GBM detection
  84. GRB 090530B: Fermi GBM detection
  85. Corrections to GRB 090531B Swift/UVOT Upper Limits
  86. GRB 090531B, RIMOTS optical upper limits
  87. GRB 090531B: Swift/UVOT Upper Limits
  88. GRB 090529: MITSuME optical observation
  89. GRB 090530: GRT Optical Observation
  90. Initial Swift/UVOT observations of GRB 090531B
  91. GRB 090531B: Swift-XRT candidate afterglow position
  92. GRB 090531B: ROTSE-III Optical Limits
  93. GRB 090531B: Swift detection of a burst
  94. GRB090530: R-band Observation
  95. GRB 090530: break in light curve
  96. GRB 090529: VLT spectroscopic redshift
  97. GRB 090531: GROND upper limits
  98. GRB 090531: P60 Observations
  99. GRB 090531: Swift detection of a burst
  100. GRB 090529: NOT optical observations

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