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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').

19138 results found.

  1. GRB 160223B: Khureltogot optical observations
  2. GRB 160223B: Swift-XRT observations
  3. GRB 160223B: LCOGT-FTN optical observations
  4. GRB 160223B: Swift ToO observations
  5. GRB 160223A: GROND optical/NIR afterglow
  6. LVC GW 150914: TAROT/TZAC Final analysis correction
  7. GRB 160221A: GROND upper limits
  8. Correction to the title of Swift GCN 19051
  9. GRB 160220B: Further GROND Observations
  10. Further Swift/UVOT observations of GRB 160220B
  11. GRB 160221A: Swift-XRT observations
  12. GRB 160221A: MASTER-SAAO early observations
  13. GRB 160221A: Swift ToO observations
  14. GRB 160220B: GROND Observations
  15. GRB 160220A: nIR observations at AAT
  16. GRB160220B: Swift/UVOT observations
  17. LIGO/Virgo GW150914
  18. GRB160220A: Swift/UVOT observations
  19. Swift Trigger 674752 is likely a noise fluctuation in the direction of IGR17488-3253
  20. GRB 160220A: TAROT Calern and TAROT La Silla observatory optical observations
  21. GRB 160220A: MASTER-Amur observations
  22. GRB 160220A: GROND Optical/NIR Upper Limits
  23. GRB 160220A: Swift-XRT observations
  24. LIGO/Virgo G184098: Correction for GCN Circular 18361
  25. GRB 160216A: Swift/UVOT Upper Limits
  26. GRB 160131A: second epoch observations with the GMRT
  27. Low frequency GMRT observations of GRB 160131A
  28. GRB 160206A: Kiso/KWFC optical observations
  29. LIGO/Virgo G211117: LOFAR follow-up
  30. GRB 160131A: TSHAO optical observations
  31. Swift Trigger 672897 is probably not an astrophysical event
  32. GRB 151215A: TAROT Calern observatory very early optical detection
  33. GRB 160206A: Swift/UVOT observations
  34. GRB 160203A: Zadko observatory - Gingin optical detection
  35. GRB 160206A: GROND Observations
  36. GRB 160206A: Swift-XRT observations
  37. GRB 160206B: iPTF P48 Observations and Optical Transient Candidates
  38. GRB 160206A: Tiled Swift observations
  39. GRB 160131A: TSHAO optical observations
  40. GRB 160131A: Mondy optcial observations
  41. GRB 160203A: TSHAO optical observations
  42. GRB 160203A: RATIR Optical Observations
  43. GRB 160131A: RATIR Optical Observations
  44. GRB 160203A: Skynet PROMPT-CTIO observations of the optical afterglow
  45. GRB 160203A: TAROT La Silla - TAROT Calern - Zadko observations
  46. GRB 160203A: Swift/UVOT Detection
  47. The bright GRB160203A: X-shooter spectroscopy and redshift
  48. GRB 160203A: LCOGT-Cerro Tololo optical afterglow confirmation
  49. GRB 160203A: GROND Afterglow Candidate
  50. GRB 160131A: VLA detection
  51. GRB160131A: NOEMA detection of the millimetre afterglow
  52. GRB 160131A: Optical observations from T150 OSN
  53. GRB 160131A: AbAO optical observations
  54. GRB 160131A: Mondy optical observations
  55. GRB 160131A Swift/UVOT Detection
  56. GRB 160131A: GROND Detection of the Optical/NIR Afterglow
  57. GRB 160131A: GTC spectroscopy of the afterglow
  58. GRB 160131A: TNG spectroscopic observations and redshift
  59. GRB 160131A: Bassano Bresciano Observatory optical observations
  60. GRB 160131A: Khureltogot optical observations
  61. GRB 160131A: TNG optical observations
  62. GRB 160131A: iTelescope optical observations
  63. GRB 160131A: LCOGT-SSO optical observations
  64. GRB 160131A: RATIR Optical Observations
  65. GRB 160131A: Xinglong 60cm WFT optical observation
  66. GRB 160131A: LCOGT-FTN optical afterglow observations
  67. GRB 160127A: RATIR Optical Observations
  68. GRB 160127A: Khureltogot optical observations
  69. GRB 160127A: VLA Detection
  70. GRB 160127A: LCOGT-Sutherland optical upper limit
  71. GRB 160127A: Swift/UVOT Detection
  72. GRB 160123A: TAROT La Silla observatory optical observations
  73. GRB 160127A: RATIR Optical Observations
  74. GRB 160127A: TAROT La Silla observatory optical light curve
  75. LIGO Virgo G211117: MWA Observations
  76. GRB 160123A: GROND Upper limits
  77. GRB 160121A: RATIR Optical Observations
  78. GRB 160123A: NOT J-band observations
  79. GRB 160123A: Swift/UVOT Upper Limits
  80. GRB 160121A: redshift from the 10.4m GTC
  81. GRB 160121A: RATIR Optical Observations
  82. GRB 160121A: Swift/UVOT Upper Limits
  83. GRB 160121A: GROND Afterglow observations
  84. GRB 160117B: RATIR continued observations
  85. LIGO/VIRGO G184098: Summary of VLA results for iPTF15cyk
  86. GRB 160121A: MASTER-Amur observations
  87. GRB 160117A: Swift-XRT afterglow detection
  88. GRB 160119A: VLA Detection
  89. GRB 160117B: VLA Detection
  90. GRB 160117B: further RATIR observations
  91. GRB 160119A: afterglow confirmation from the NOT
  92. GRB 160119A: Swift/UVOT Upper Limits
  93. LIGO/Virgo G184098: MASTER final result
  94. GRB 160119A: GROND optical/NIR afterglow observations
  95. GRB 160119A: RATIR Optical and NIR Observations
  96. GRB 160117B: RATIR Optical and NIR Observations
  97. GRB 160117B: further NOT optical observations of the afterglow
  98. GRB 160119A: NOT and GTC afterglow candidate
  99. GRB 160117A: Swift/UVOT Upper Limits
  100. GRB 160104A: ISON-Ussuriysk optical observations

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