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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').

675 results found.

  1. GRB 150428A: RATIR optical observations
  2. GRB 150428A: P60 observations
  3. GRB 150428A: GROND Dark Burst Host Candidate
  4. GRB 150424A: RATIR Observations
  5. GRB 150424A: GROND detects strong fading
  6. GRB 150423A: Continued RATIR optical afterglow monitoring
  7. GRB 150423A: RATIR optical afterglow monitoring
  8. GRB 150423A: GROND afterglow candidate
  9. GRB 150423A: GROND observation
  10. GRB 150318A : GROND upper limits
  11. GRB 150301B: GROND afterglow observations
  12. GRB 150301A: Swift/UVOT Upper Limits
  13. GRB 150301A: GROND Observations
  14. GRB 150222A: Further GROND Observations
  15. GRB 150222A: GROND optical afterglow candidate
  16. GRB 150204A: GROND observations
  17. GRB 150206A: GROND afterglow observations
  18. GRB 150203A: GROND Upper limits
  19. GRB 150202A: GROND Upper limits
  20. GRB 150201A: GROND upper limits
  21. GRB 150120B: RATIR Optical and NIR Observations
  22. GRB 150120B: GROND Afterglow Detection
  23. Christmas GRB 141225A: GROND Observations
  24. GRB141221A: GROND Afterglow Detection
  25. GRB 141121A: LCO-FTN observations
  26. GRB 141121A: GROND Afterglow candidate
  27. GRB 141109A: GROND afterglow observation
  28. GRB 141017A: Skynet PROMPT-CTIO/SSO Observations
  29. GRB 141022A: Skynet PROMPT-CTIO Observations
  30. GRB 141031A: Skynet PROMPT-CTIO Observations
  31. GRB 141031A: VLT/X-shooter optical observations
  32. GRB 141031A: GROND detection of a possible optical afterglow candidate
  33. GRB 140509A: GROND afterglow detection
  34. GRB 141028A: Swift/UVOT followup observations
  35. GRB 141028A: Swift-XRT observations
  36. GRB 141028A: LCOGTN observations
  37. GRB 141028A: Swift/UVOT Detection
  38. GRB 141028A: Swift/XRT detection of the X-ray afterglow
  39. GRB 141028A: GROND Afterglow confirmation (MASTER source)
  40. GRB 141026A: GTC spectroscopy
  41. GRB 141026A: GROND observations
  42. GRB 141022A: GROND Detection of a possible Optical Afterglow Candidate
  43. GRB 141004A: RATIR Late Time Optical and NIR Observations
  44. GRB 141017A: GROND Afterglow Confirmation
  45. GRB 141004A: GROND observations
  46. GRB 141005A: GROND observations
  47. GRB 140930B: GROND observations
  48. GRB 140928A: LCO-Cerro Tololo observations
  49. GRB 140928A: GROND Afterglow Candidate
  50. GRB 140919A: GROND afterglow candidate
  51. GRB 140818A: GROND confirmation of afterglow candidate
  52. GRB140819A: Deep GROND Upper Limits
  53. GRB 140818B : Correction to GCN 16713
  54. GRB 140818B: Swift/UVOT Upper Limits
  55. GRB140818B : GROND afterglow candidate
  56. GRB 140815A: GROND afterglow candidate
  57. GRB 140801A: GROND Afterglow detection, unbroken decay
  58. GRB 140730A: GROND Upper limits
  59. GRB 140716A: GROND confirmation of the afterglow
  60. GRB 140719A: FTS observations
  61. GRB 140719A: GROND Afterglow candidate
  62. GRB 140716A: Swift/UVOT Upper Limits
  63. GRB 140716A: GROND afterglow candidate
  64. GRB 140710A: P60 Confirmation of Afterglow
  65. GRB 140710A: GROND Detection of NIR Afterglow Candidate
  66. GRB140706A: GROND detection of the Optical/NIR afterglow
  67. GRB 140628A: GROND observation of the afterglow
  68. GRB 140626A: GROND Afterglow Candidate
  69. GRB 140622A: GROND Upper limits
  70. GRB 140614A: GROND afterglow candidate
  71. GRB 140408A: Withdrawal of afterglow candidate
  72. GRB 140515A: GROND observation of the afterglow
  73. GRB140512A : GROND observations
  74. GRB 140428A: GROND afterglow confirmation
  75. GRB 140428A: GROND observations
  76. GRB 140413A: GROND Afterglow Confirmation
  77. GRB 140413A: TAROT La Silla observatory optical observations
  78. GRB 140413A: GROND afterglow candidate
  79. GRB 140408A: RATIR Optical Upper Limits
  80. GRB 140408A: GROND Detection of an Afterglow Candidate
  81. GRB 140302A: GROND confirmation of the afterglow
  82. GRB 140301A: GROND Detection of the Optical/NIR Afterglow
  83. GRB 140302A: GROND afterglow candidate
  84. PTF14yb: GROND Transient Detection
  85. GRB 140213A: GROND Detection of the Optical/NIR Afterglow
  86. GRB 140102A: GROND observations
  87. GRB 131229A: GROND observations
  88. GRB 131227A: GROND Upper Limits
  89. GRB 131218A: GROND Upper Limits
  90. GRB 131205A: GROND confirmation of afterglow
  91. GRB131202A : GROND observations
  92. GRB131205A : GROND Observations
  93. GRB 131128A: GROND observations of the afterglow
  94. GRB 131117A: GROND confirmation of the afterglow and photo-z.
  95. GRB 131024A: GROND upper limits
  96. GRB 131014A: GROND observations
  97. iPTF 13dsw/Fermi403206457: X-Shooter redshift
  98. GRB 131011A: GROND afterglow observations
  99. GRB 131004A: RATIR Optical and NIR Upper Limits
  100. GRB 131004A: GROND observations of the afterglow

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