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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"

28263 results found.

  1. GRB 180618A: Swift detection of a burst with an optical counterpart
  2. GRB 180614A: AbAO optical observations
  3. GRB 180614A: Swift/UVOT Upper Limits
  4. GRB 180614A: Swift-BAT refined analysis
  5. GRB 180614A: NOT optical upper limits
  6. GRB 180614A: Swift-XRT refined Analysis
  7. GRB 180614A: Enhanced Swift-XRT position
  8. GRB 180614A: Swift detection of a burst
  9. GRB 180613A: Swift/UVOT Upper Limits
  10. GRB 180613A GROND observations
  11. GRB 180613A: Possible IR afterglow
  12. GRB 180613A: Swift-XRT refined Analysis
  13. GRB 180613A: Enhanced Swift-XRT position
  14. GRB 180613A: Possible host galaxy at XRT position, or star
  15. GRB 180613A: Swift detection of a burst
  16. GRB 180611A: Fermi GBM observation
  17. GRB 180605A: Fermi GBM observation
  18. GW170817/GRB170817A: LBT optical detection
  19. GRB 180602B: Fermi GBM detection
  20. GRB 180602A: Swift/UVOT Upper Limits
  21. GRB 180602A: MITSuME Akeno optical upper limits
  22. GRB 180602A: Swift-XRT refined Analysis
  23. GRB 180602A: Swift-BAT refined analysis
  24. GRB 180602A: MITSuME Okayama optical upper limits
  25. GRB 180602A: Enhanced Swift-XRT position
  26. GRB 180602A: Swift detection of a burst
  27. IPN Triangulation of GRB 180529A (short/hard)
  28. Swift Trigger 834937 is not a GRB
  29. IPN Triangulation of GRB 180526A (long)
  30. IPN Triangulation of GRB 180523A
  31. GRB180523B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 548793993)
  32. GRB 180514A: CrAO/ZTSH optical observations and afterglow candidate
  33. GRB 180514A: Swift/UVOT Upper Limits
  34. GRB 180514A: Detection limits from 2.5m NOT
  35. GRB 180510A: MITSuME Ishigakijima optical upper limits
  36. GRB 180514A: 1.5m OSN optical observations
  37. GRB 180514A: GOTO Optical Observations
  38. GRB 180514A: Swift-BAT refined analysis
  39. GRB 180514A: Swift-XRT refined Analysis
  40. GRB 180514A: Enhanced Swift-XRT position
  41. GRB 180512A: VLT/HAWK-I NIR Observations
  42. GRB 180514A: Swift detection of a burst
  43. Konus-Wind observation of GRB 180510A
  44. GRB 180512A: Swift-XRT refined Analysis
  45. GRB 180512A: Swift-BAT refined analysis
  46. GRB 180512A: RATIR Optical Observations
  47. GRB 180512A: LBT optical detection
  48. GRB 180512A: Swift/UVOT Upper Limits
  49. GRB 180512A: Enhanced Swift-XRT position
  50. GRB 180512A: GROND upper limits
  51. GRB 180512A: NOT upper limits
  52. GRB 180512A: OASDG optical observations
  53. GRB 180512A: Upper limits from OSN
  54. GRB 180512A: Swift detection of a burst
  55. GRB 180510A: Swift/UVOT followup observations
  56. GRB 180510B: Swift-XRT refined Analysis
  57. GRB 180510A: Swift-XRT refined Analysis
  58. Swift trigger 831888: misidentification of 4U 1416-62
  59. GRB 180510B: Swift-BAT refined analysis
  60. GRB 180510B: VLT/X-shooter observations
  61. GRB 180510B: GROND detection in all bands
  62. GRB 180510B: TAROT La Silla observatory optical observations
  63. Swift Trigger 831888: a possible GRB or Galactic transient
  64. GRB 180510B: Enhanced Swift-XRT position
  65. GRB 180418A: 15 GHz upper limits from AMI
  66. GRB 180510B: Swift detection of a burst with an optical counterpart
  67. GRB 180510A: Swift detection of a burst
  68. Chandra observations of GW170817 reveal a fading afterglow
  69. Chandra observations of GW170817 260 days since merger: first statistically significant evidence for an X-ray decay
  70. GRB 180504A: Swift/UVOT Upper Limits
  71. GRB 180504A: Swift-BAT refined analysis
  72. GRB 180505A: Fermi GBM detection
  73. GRB 180504A: ePESSTO NTT NIR observations
  74. Correction to Swift-XRT light curve fit for GRB 180504A in GCN 22685
  75. GRB 180504A: Swift-XRT refined Analysis
  76. GRB 180504A: NOT afterglow candidate
  77. GRB 180504A: Swift detection of a burst
  78. IPN Triangulation of GRB 180427A
  79. GRB 180427A: Fermi GBM detection
  80. GRB 180425A: Swift-XRT refined Analysis
  81. GRB 180425A: Swift-BAT refined analysis
  82. GRB 180425A: Swift/UVOT Upper Limits
  83. GRB 180425A: Enhanced Swift-XRT position
  84. GRB 180425A: Swift detection of a burst
  85. GRB 180418A: TAROT La Silla observatory early optical observations
  86. GRB 180418A: MITSuME Ishigakijima Optical Observation
  87. GRB 180418A : SQUEAN observations
  88. GRB 180418A: Further GROND observations
  89. GRB 180418A: Swift/UVOT Detection
  90. GRB 180418A: Continued RATIR Optical Observations
  91. GRB 180418A: Imaging of the optical afterglow with the 1.3 m DFOT and 3.6 m DOT in ARIES, India
  92. GRB 180418A GROND observations
  93. GRB 180418A: Gemini-North imaging and spectroscopy
  94. GRB 180418A: Swift-BAT refined analysis
  95. GRB 180418A: Swift-XRT refined Analysis
  96. GRB 180418A: RATIR Optical Observations
  97. LIGO/Virgo G299232: LOFAR follow-up
  98. GRB 180418A: Enhanced Swift-XRT position
  99. GRB 180418A: Swift-XRT observations
  100. GRB 180416A: Fermi GBM detection

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