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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"

21041 results found.

  1. GRB 180624A: LCO Haleakala observations
  2. GRB 180626A: Swift/UVOT Detection
  3. GRB 180626A: LCO Haleakala observations
  4. GRB 180626A: ISON-MN optical observations
  5. GRB 180624A: RATIR Optical Observations
  6. GRB 180624A: LBT/MODS redshift measurement
  7. GRB 180613A: LCO Afterglow detection
  8. GRB 180624A: GROND observations
  9. GRB 180624A: Swift/UVOT Upper Limits
  10. GRB 180623A: Swift/UVOT Detection
  11. GRB 180620B: Swift/UVOT Detection
  12. GRB 180620B: VLT/X-shooter redshift
  13. GRB 180613A: Afterglow confirmation and added photometry
  14. GROND observations of GRB 180620B
  15. GROND observations of GRB 180620A
  16. GRB 180620A: KAIT Optical Observations
  17. GRB 180620A: Xinglong-2.16m optical observations
  18. GRB 180618A: Swift/UVOT Detection
  19. GRB 180620A: Swift/UVOT Detection
  20. GRB 180620A: LCO McDonald observations
  21. GRB 180620A: MASTER OT observation
  22. GRB 180620A: RATIR Optical Afterglow Detection
  23. GRB 180618A: MASTER OT observation (a short GRB with extended emission)
  24. GRB 180618A: LT prompt observations
  25. GRB 180614A: AbAO optical observations
  26. GRB 180614A: Swift/UVOT Upper Limits
  27. GRB 180614A: NOT optical upper limits
  28. GRB 180614A: MASTER observation
  29. GRB 180613A: Swift/UVOT Upper Limits
  30. GRB 180613A GROND observations: correction
  31. GRB 180613A GROND observations
  32. GRB 180613A: Possible IR afterglow
  33. GW170817/GRB170817A: LBT optical detection
  34. GRB 180602A: Swift/UVOT Upper Limits
  35. GRB180523B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 548793993)
  36. GRB 180514A: CrAO/ZTSH optical observations and afterglow candidate
  37. GRB 180514A: Swift/UVOT Upper Limits
  38. GRB 180514A: 1.5m OSN optical observations
  39. GRB 180514A: GOTO Optical Observations
  40. GRB 180512A: VLT/HAWK-I NIR Observations
  41. GRB 180512A: RATIR Optical Observations
  42. GRB 180512A: LBT optical detection
  43. GRB 180512A: Swift/UVOT Upper Limits
  44. GRB 180512A: LT prompt observations
  45. GRB 180512A: GROND upper limits
  46. GRB 180512A: NOT upper limits
  47. GRB 180512A: OASDG optical observations
  48. GRB 180512A: Upper limits from OSN
  49. GRB 180510A: Swift/UVOT followup observations
  50. GRB 180510B: VLT/X-shooter observations
  51. GRB 180510B: GROND detection in all bands
  52. GRB 180510B: TAROT La Silla observatory optical observations
  53. GRB 180418A: 15 GHz upper limits from AMI
  54. Chandra observations of GW170817 reveal a fading afterglow
  55. Chandra observations of GW170817 260 days since merger: first statistically significant evidence for an X-ray decay
  56. GRB 180504A: Swift/UVOT Upper Limits
  57. GRB 180504A: ePESSTO NTT NIR observations
  58. GRB 180504A: NOT afterglow candidate
  59. GRB 180425A: Swift/UVOT Upper Limits
  60. GRB 180418A: TAROT La Silla observatory early optical observations
  61. GRB 180418A : SQUEAN observations
  62. GRB 180418A: Further GROND observations
  63. GRB 180418A: Swift/UVOT Detection
  64. GRB 180418A: Continued RATIR Optical Observations
  65. GRB 180418A: Imaging of the optical afterglow with the 1.3 m DFOT and 3.6 m DOT in ARIES, India
  66. GRB 180418A GROND observations
  67. GRB 180418A: NOT optical observations
  68. GRB 180418A: Gemini-North imaging and spectroscopy
  69. GRB 180418A: 1.5m OSN optical observations
  70. GRB 180418A: RATIR Optical Observations
  71. LIGO/Virgo G299232: LOFAR follow-up
  72. GRB 180418A: Swift-XRT observations
  73. GRB 180418A: KAIT Optical Afterglow Candidate
  74. GRB 180409A: Swift-XRT afterglow detection
  75. GRB 180411A: Swift/UVOT Upper Limit
  76. GRB 180411A: Tautenburg observations
  77. GRB 180410A: RATIR Optical Observations
  78. GRB 180410A: Swift/UVOT Upper Limits
  79. GRB 180409A: Swift-XRT observations
  80. GRB 180409A: Tiled Swift observations
  81. Swift Trigger 823014: TAROT Calern observatory optical observations
  82. GRB 180404B: Swift/UVOT Detection
  83. Chandra observations of GRB161219B 400 days after the explosion
  84. GRB 180404A: Swift/UVOT Detection
  85. GRB 180404A: LCO FTS observations
  86. GRB 180404B: MASTER-OAFA OT observation
  87. GRB 180404A: MASTER-OAFA OT observation
  88. GRB 180404A: VLT/X-shooter redshift
  89. GRB 180402A: Swift/UVOT Upper Limits
  90. GRB 180402A: KAIT Optical Upper Limit
  91. GRB 180402A: LCO McDonald observations
  92. GRB 180331B: Swift/UVOT Upper Limits
  93. GRB 180331B: AbAO optical observations
  94. GRB 180329B: LCO FTS observations
  95. GRB 180331A: Swift/UVOT Upper Limits
  96. GRB 180329B: VLT/X-shooter spectroscopic observations
  97. GRB 180329B: Swift/UVOT Detection
  98. GRB 180329B: RATIR Optical Observations
  99. GRB 180329B: NOT optical afterglow detection
  100. GRB 180329A: Swift-BAT refined analysis

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