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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36146 results found.

  1. GRB 180416B: AstroSat CZTI detection
  2. Konus-Wind observation of GRB 180427A
  3. IPN Triangulation of GRB 180427A
  4. GRB 180427A: Fermi GBM detection
  5. GRB 180425A: Swift-XRT refined Analysis
  6. GRB 180425A: Swift-BAT refined analysis
  7. GRB 180425A: Swift/UVOT Upper Limits
  8. GRB 180425A: Enhanced Swift-XRT position
  9. GRB 180425A: Swift detection of a burst
  10. GRB 180418A: TAROT La Silla observatory early optical observations
  11. GRB 180418A: MITSuME Ishigakijima Optical Observation
  12. GRB 180418A : SQUEAN observations
  13. Fermi GBM trigger 545979055/180421202 is not a GRB
  14. GRB 180418A: Further GROND observations
  15. GRB 180418A: Swift/UVOT Detection
  16. GRB 180418A: Continued RATIR Optical Observations
  17. GRB 180418A: Imaging of the optical afterglow with the 1.3 m DFOT and 3.6 m DOT in ARIES, India
  18. GRB 180418A GROND observations
  19. GRB 180418A: Xinglong TNT optical upper limit
  20. GRB 180418A: NOT optical observations
  21. GRB 180418A: Gemini-North imaging and spectroscopy
  22. GRB 180418A: Swift-BAT refined analysis
  23. GRB 180418A: 1.5m OSN optical observations
  24. GRB 180418A: Fermi GBM observation
  25. GRB 180418A: Swift-XRT refined Analysis
  26. GRB 180416B: CALET Gamma-Ray Burst Monitor detection
  27. GRB 180418A: RATIR Optical Observations
  28. GRB 180418A: Enhanced Swift-XRT position
  29. GRB 180418A: Swift-XRT observations
  30. GRB 180418A: LCO FTN afterglow confirmation
  31. GRB 180418A: KAIT Optical Afterglow Candidate
  32. GRB 180418A: Swift detection of a short burst
  33. GRB 180404B: AstroSat CZTI detection
  34. GRB 180416A: Fermi GBM detection
  35. GRB 180409A: Swift-XRT afterglow detection
  36. GRB 180411A: CALET Gamma-Ray Burst Monitor detection
  37. GRB 180411B: CALET Gamma-Ray Burst Monitor detection
  38. Konus-Wind observation of GRB 180411A
  39. GRB 180411A: Swift/UVOT Upper Limit
  40. GRB 180411A: Tautenburg observations
  41. GRB 180410A: Fermi GBM observation
  42. GRB 180409A CALET Gamma-Ray Burst Monitor detection
  43. GRB 180411A: Fermi GBM detection
  44. GRB 180411A: Swift-BAT refined analysis
  45. GRB 180411A: Swift-XRT refined Analysis
  46. GRB 180410A: RATIR Optical Observations
  47. GRB 180411A: Swift detection of a burst
  48. GRB 180410A: Swift-XRT refined Analysis
  49. GRB 180410A: Swift-BAT refined analysis
  50. GRB 180410A: Swift/UVOT Upper Limits
  51. GRB 180409A: Fermi GBM observation
  52. GRB 180409A: Swift-XRT observations
  53. Konus-Wind observation of GRB 180404C
  54. GRB 180410A: MITSuME Akeno optical upper limits
  55. GRB 180410A: Enhanced Swift-XRT position
  56. Konus-Wind observation of GRB 180409A
  57. GRB 180410A: Swift detection of a burst or a Galactic transient.
  58. IPN Triangulation of GRB 180409A
  59. GRB 180409A: Tiled Swift observations
  60. GRB 180402A: ISON-NM early optical limits
  61. GRB 180407A: Swift-BAT refined analysis
  62. Swift Trigger 823014: TAROT Calern observatory optical observations
  63. GRB 180407A: COATLI Upper Limits
  64. Swift Trigger 823014 is probably not a GRB
  65. GRB 180407A: Swift detection of a burst
  66. GRB 180404B: Swift/UVOT Detection
  67. IPN Triangulation of GRB 180404C (long)
  68. Konus-Wind observation of GRB 180404B
  69. GRB 180404C CALET Gamma-Ray Burst Monitor detection
  70. GRB 180404A: Swift/UVOT Detection
  71. GRB 180404A: LCO FTS observations
  72. GRB 180404A: Swift-XRT refined Analysis
  73. GRB 180404B: Swift-BAT refined analysis
  74. GRB 180402A: Fermi GBM refined spectral analysis
  75. GRB 180404A: Swift-BAT refined analysis
  76. GRB 180404B: Swift-XRT refined Analysis
  77. GRB 180404B: Fermi GBM observation
  78. GRB 180404B: MASTER-OAFA OT observation
  79. GRB 180404B: Enhanced Swift-XRT position
  80. GRB 180404A: MASTER-OAFA OT observation
  81. GRB 180404A: Enhanced Swift-XRT position
  82. GRB 180404A: VLT/X-shooter redshift
  83. GRB 180404B: Swift detection of a burst with an optical counterpart
  84. GRB 180404A: Swift detection of a burst with an optical afterglow
  85. Konus-Wind observation of GRB 180402A
  86. GRB 180402A: Swift/UVOT Upper Limits
  87. GRB 180402A: Swift-XRT refined Analysis
  88. GRB 180402A: Fermi GBM detection
  89. GRB 180402A, Swift-BAT refined analysis
  90. GRB 180402A: KAIT Optical Upper Limit
  91. GRB 180402A: RATIR Upper Limits
  92. GRB 180402A: LCO McDonald observations
  93. GRB 180402A: Swift detection of a possibly short burst
  94. GRB 180331B: Swift/UVOT Upper Limits
  95. GRB 180331B: Swift-XRT refined Analysis
  96. GRB 180331B: AbAO optical observations
  97. GRB 180331B: Swift-BAT refined analysis
  98. GRB 180331B: Enhanced Swift-XRT position
  99. GRB 180331A: Swift-BAT refined analysis
  100. GRB 180331B: Swift detection of a burst

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