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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"

27018 results found.

  1. GRB 120403B: Swift/UVOT Upper Limits
  2. GRB 120403B: Swift detection of a burst
  3. BAT trigger 519207 was a burst from Cyg X-1, was not GRB 120402A
  4. GRB 120402A: optical upper limit
  5. GRB 120320A: early optical upper limit
  6. GRB 120403A, Swift-BAT refined analysis
  7. GRB 120402B: Fermi GBM detection
  8. GRB 120326A: Bassano Bresciano Observatory - correction for GCN Cir 13178
  9. GRB 120403A: Swift detection of a burst
  10. GRB 120402A: Swift detection of a possible burst or noise
  11. GRB 120326A: Cima Rest and Bassano Brescia
  12. GRB 120401A: Swift-XRT refined Analysis
  13. GRB 120401A: Swift-BAT refined analysis
  14. GRB 120401A: Swift detection of a burst
  15. GRB 120326A: Bassano Bresciano Observatory lightcurve analisis
  16. GRB 120326A : Suzaku WAM observation of the prompt emission
  17. GRB 120326A: CARMA 3mm detection
  18. Swift trigger 518853 is most likely GX 301-2
  19. GRB 120326A: Bassano Bresciano Observatory optical observations
  20. Swift trigger 518853: MASTER-ICATE possible OT
  21. The Swift-XRT source associated with trigger 518853 is a cosmic ray
  22. Trigger 518853: Swift detection of a probable Galactic transient
  23. GRB 120328B: Fermi-LAT Observations
  24. GRB 120327A: Zadko optical observations
  25. GRB 120328B: Fermi GBM detection
  26. GRB 120328A: Swift/UVOT Upper Limits
  27. GRB 120328A: Swift-XRT refined Analysis
  28. IPN Triangulation of GRB 120328B (long/intense)
  29. GRB 120328A: Swift-BAT refined analysis
  30. GRB 120328A: TAROT La Silla observatory optical observations
  31. Skynet/PROMPT observations of GRB120328A
  32. GRB 120328A: Swift detection of a burst
  33. GRB 120326A: Fermi GBM Observation
  34. GRB 120327A afterglow detection
  35. GRB 120326A: PAIRITEL NIR Observations
  36. GRB 120326A: Bassano Bresciano Observatory optical observations
  37. GRB 120327A: Swift-XRT refined Analysis
  38. GRB 120327A: Swift/UVOT further analysis
  39. GRB 120327A: Swift-BAT refined analysis
  40. GRB 120327A: X-shooter redshift
  41. GRB 120327A: Gemini-South redshift
  42. GRB 120327A: TAROT La Silla observatory optical decay
  43. GROND observations of GRB 120327A
  44. GRB 120327A: Liverpool Telescope Observations
  45. GRB 120327A: TAROT La Silla observatory optical detection
  46. GRB 120327A: Swift detection of a burst with an optical counterpart
  47. GRB 120326A: Swift-BAT refined analysis
  48. GRB 120326A: T17 optical observations
  49. GRB 120326A: Swift-XRT refined Analysis
  50. GRB 120326A: Swift/UVOT Detection
  51. GRB 120326A: Liverpool Telescope observations
  52. Skynet/Dolomiti Observations of GRB120326A
  53. GRB 120326A: TAROT Calern observatory afterglow optical detection
  54. GRB 120326A: ROTSE-III Optical Limits
  55. GRB 120326A: Swift detection of a burst
  56. GRB 120323A: Fermi LAT observations
  57. IPN Triangulation of GRB 120323A (short/very intense)
  58. GRB 120324A: Swift-XRT refined Analysis
  59. Konus-Wind observation of GRB 120324A
  60. GRB 120323A: Fermi GBM detection
  61. GRB 120324A: GROND observations
  62. GRB 120324A: Swift-BAT refined analysis
  63. GRB 120324A: Swift/UVOT Upper Limits
  64. GRB 120324A: TAROT La Silla observatory optical observations
  65. GRB 120324A: Liverpool Telescope optical candidate
  66. GRB 120324A: UVOT Finding Chart Observation
  67. GRB 120324A: Swift detection of a burst
  68. GRB 120316A : Suzaku WAM observation of the prompt emission
  69. GRB 120320A: Zadko optical observations
  70. GRB 120316A: Fermi-GBM and Fermi-LAT Observations
  71. GRB 120320A: Swift/UVOT Upper Limits
  72. GRB 120320A , optical observations
  73. GRB 120320A: Swift-XRT refined Analysis
  74. GRB 120320A, Swift-BAT refined analysis
  75. Fermi GBM trigger 120319.237 is not a GRB
  76. Konus-Wind observation of GRB 120316A
  77. IPN Triangulation of GRB 120316A
  78. GRB 120320A: Swift detection of a burst
  79. GBM trigger 353549464 (GRB 120316A?) : High-energy photon emission in Fermi/LAT data
  80. Trigger 517876 is a Swift detection of GX 5-1
  81. Fermi GBM triggers 120309.265 and 120309.402 are not GRBs
  82. Fermi GBM triggers 120305.186, 120305.802 and 120306.823 are not GRBs
  83. GRB 120311A: Optical follow-up
  84. GRB 120311A: C88 optical limits
  85. GRB 120312A: Swift/UVOT Upper Limits
  86. GRB 120312A: Swift-XRT refined Analysis
  87. GRB 120312A: Swift-BAT refined analysis
  88. GRB 120311A: VLT/X-shooter observations
  89. GRB 120311B: C88 optical limits
  90. GRB 120312A: Swift detection of a burst
  91. GROND observations of GRB 120311A
  92. GRB 120311B: Swift/UVOT Upper Limits
  93. GRB 120311B: Faulkes Telescope North observations
  94. GRB 120311B: Swift-XRT refined Analysis
  95. GRB 120311A: Swift-XRT refined Analysis
  96. GRB 120311B: Swift-BAT refined analysis
  97. GRB 120311B: Swift-XRT observations
  98. GRB 120311A, Swift-BAT refined analysis
  99. GRB 120311B: Swift detection of a burst
  100. GRB 120311A: Swift/UVOT Upper Limits

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