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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"
  1. GRB110731A: MITSuME Ishigakijima Optical Upper Limits
  2. GRB 110731A Gemini-N redshift
  3. GRB 110731A: Swift-XRT refined Analysis
  4. Konus-Wind observation of GRB 110731A
  5. GRB110731A: Swift/UVOT Observations
  6. GRB 110731A: Fermi GBM observation
  7. GRB 110731A: NOT photometry
  8. GRB 110731A: Enhanced Swift-XRT position
  9. Fermi-LAT Detection of GRB110731A
  10. GRB 110731A: Swift-BAT refined analysis
  11. GRB 110731A: FTN+FTS afterglow observations
  12. GRB 110731A: Swift detection of a burst with an optical counterpart
  13. Sw J1644+57 (GRB 110328A): Continued VLBA Observations
  14. INTEGRAL Weak trigger #6331: GRT Optical Observation
  15. GRB 110721A: Swift observations of afterglow candidate
  16. AXP 4U 0142+61: Swift-BAT refined analysis
  17. GRB 110726A: optical upper limit in CrAO
  18. Swift detection of a SGR-like burst from the AXP 4U 0142+61
  19. Swift triggers 458268 and 458269 are not astrophysical
  20. GRB 110726A: EVLA observations
  21. GRB 110726A: IAC80 R-band observations
  22. GRB 110726A: ROTSE-III refined analysis, fast decay in early phase
  23. GRB110726A: MITSuME Ishigakijima Optical Observation
  24. GRB 110726A: Further Swift/UVOT Observations
  25. GRB110726A: Gemini-N tentative redshift
  26. GRB 110726A: Swift-BAT refined analysis
  27. GRB 110726A: Enhanced Swift-XRT position
  28. GRB 110726A: Swift/UVOT Detection
  29. GRB 110726A: Liverpool Telescope observations
  30. GRB 110726: ROTSE-III Detection of Optical Counterpart
  31. GRB 110726A: Swift detection of a burst
  32. IPN triangulation of GRB 110721A
  33. GRB 110721A: Preliminary Swift/UVOT Upper Limits
  34. GRB 110721A: Gemini-South spectroscopy of the potential optical counterpart
  35. GRB 110721A: potential counterpart candidate
  36. Konus-Wind observation of GRB 110721A
  37. GRB 110709B / EVLA detection of radio counterpart
  38. GRB 110719A / SMA 345 GHz upper limits
  39. GRB 110721A: Fermi-LAT detection
  40. GRB 110721A: Fermi GBM detection
  41. Recent GCN/Swift-BAT Slew Burst Position notices are due to playback debugging
  42. GRB110715A: spectral lag analysis
  43. GRB 110715A : Suzaku WAM observation of the prompt emission
  44. GRB 110719A: GRT Optical Observation
  45. GRB 110719A: optical limit by "Pi of the Sky"
  46. GRB 110719A: z-band upper limit
  47. Swift/UVOT observations of GRB110719A
  48. Swift J1822.3-1606 : Fermi GBM observation
  49. GRB 110719A: Swift-XRT refined Analysis
  50. GRB 110719A: optical upper limit
  51. GRB 110719A: Enhanced Swift-XRT position
  52. GRB 110719A: Swift-BAT refined analysis
  53. GRB 110715A optical observations
  54. GRB 110719A: Swift detection of a burst
  55. GRB 110709B : Suzaku WAM observation of the prompt emission
  56. GRB 110715A: ATCA detection of the radio counterpart
  57. Swift J1822.3-1606: Transient Magnetar or Be X-ray Binary?
  58. GRB110715A: GROND Detection of the Optical/NIR Afterglow
  59. GRB 110715A: APEX detection of the submm counterpart
  60. Swift J1822.3-1606
  61. Konus-Wind observation of GRB 110715A
  62. GRB 110715A: Swift-XRT refined Analysis
  63. GRB110715A: VLT redshift
  64. Swift J1822.3-1606: Swift-XRT detection of the X-ray counterpart
  65. GRB 110715A: Swift/UVOT Detection
  66. GRB 110715A: Enhanced Swift-XRT position
  67. GRB 110715A: Swift-BAT refined analysis
  68. Swift J1822.3-1606: A Probable New SGR in Ground Analysis of BAT Data
  69. GRB 110715A: Swift detection of a bright burst with an optical counterpart
  70. GRB 110709B: Swift/UVOT Observations
  71. GRB 110709A / EVLA upper limits
  72. GRB 110709B: Additional Gemini observations and deep limits on an optical afterglow
  73. Swift trigger 457076 is not a GRB
  74. Konus-Wind observation of GRB 110708B
  75. GRB 110709A: Suzaku WAM observation of the prompt emission
  76. GRB 110709B: Submm observations from APEX
  77. IPN triangulation of GRB 110708B (long duration, extremely intense)
  78. Swift Trigger 457076: a possible GRB
  79. GRB 110709A: Swift/UVOT Upper Limits
  80. Fermi Gamma-ray Burst Monitor trigger 332078586 is not a GRB
  81. GRB 110709A: Konkoly observations
  82. GRB 110708A: Konkoly observations
  83. GRB 110709B BAT refined analysis
  84. GRB 110709B: burst detection from Swift-BAT slew data
  85. GRB 110709B: Swift-XRT refined Analysis
  86. GRB 110709A: Swift-XRT refined Analysis
  87. GRB 110709B: Swift/UVOT Detection of Possible Optical Flaring
  88. GRB110709A: MITSuME Ishigakijima Optical upper limits
  89. Konus-Wind observation of GRB 110709A
  90. GRB 110709B: correction to GCN 12135 (Konus-Wind peak flux)
  91. GRB 110709B: Enhanced Swift-XRT position
  92. Konus-Wind observation of GRB 110709B
  93. GRB110709A: upper limits from CAHA 1.23m and OSN 1.5m
  94. GRB 110709A: Fermi GBM observation
  95. GRB 110709B: Gemini-South additional analysis and photometry
  96. GRB 110709B : A possible source in USNO B 1.0
  97. GRB 110709B: Preliminary Swift-BAT refined analysis
  98. GRB 110709B: GROND Detection of an Afterglow Candidate
  99. GRB 110709B: Gemini-South optical observations
  100. GRB 110709A: Swift-BAT refined analysis

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