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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').
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"

675 results found.

  1. GRB 111229A: Swift/UVOT Detection
  2. GRB 111229A: Faulkes Telescope South observations
  3. GRB 111229A: GROND afterglow candidate
  4. GRB 111228A: GROND observations
  5. GRB 111212A: GROND observations
  6. GRB 111211A: VLT/X-shooter redshift
  7. GRB 111211A: Swift/XRT target of opportunity observation
  8. GRB 111211A: GROND afterglow candidate
  9. GRB 111210A: GROND observations
  10. GRB 111209A: Rebrightening seen by GROND
  11. GRB 111209A: GROND Afterglow observations
  12. GRB 111205A: GROND observations
  13. GRB 111117A: Refined GMG observation
  14. GRB 111204A: GROND Observations
  15. GRB 111129A, GROND afterglow observations
  16. GRB 111123A, GROND observations
  17. GRB 111117A: GROND observations
  18. GRB 111107A: GROND observations
  19. GRB 111018A: GROND Upper Limits
  20. GRB 111008A, GROND observations
  21. GRB 111005A: GROND NIR observations
  22. GRB 110825A: GROND Observations
  23. GRB 110918A: GROND detection of the afterglow candidate
  24. GRB 110915B: GROND Observations of the Optical/NIR Afterglow Candidate
  25. GRB 110915A: GROND Upper limits
  26. GRB 110721A: Swift observations of afterglow candidate
  27. GRB 110721A: Preliminary Swift/UVOT Upper Limits
  28. GRB 110721A: Gemini-South spectroscopy of the potential optical counterpart
  29. GRB 110721A: potential counterpart candidate
  30. GRB110715A: GROND Detection of the Optical/NIR Afterglow
  31. GRB 110709B: Swift/UVOT Detection of Possible Optical Flaring
  32. GRB 110709B: Gemini-South additional analysis and photometry
  33. GRB 110709B: GROND Detection of an Afterglow Candidate
  34. GRB 110625A: GROND detection of a source inside the XRT error circle
  35. GRB110420A: GROND detection of the Optical/NIR Afterglow Candidate
  36. GRB 110420B, GROND observations
  37. GRB 110414A: GROND upper limits
  38. GRB110407A: UVOT Upper Limits
  39. GRB 110407A: GROND Detection of the Optical Afterglow
  40. GRB 110319B: GROND upper limits
  41. GRB 110318B: GROND upper limits
  42. GRB 110312A: GROND Upper Limits
  43. GRB 110305A: Swift/UVOT Upper Limits
  44. GRB 110305A: GROND Detection of Optical Afterglow
  45. Swift/UVOT observations of GRB110223b
  46. GRB 110223B: GROND Detection of Optical Afterglow Candidate
  47. GRB 110213B: Swift/UVOT observations
  48. GRB 110213B: GROND observations of the optical/NIR afterglow
  49. GRB 110206A: Decay of afterglow candidate
  50. GRB 110206A: GROND detection of afterglow candidate
  51. GRB 101219B: tentative redshift and spectroscopic supernova detection
  52. GRB 101219B: GROND detection of a SN signature
  53. GRB 101219B: GROND Detection of the Optical/NIR Afterglow
  54. GRB 101219A: GROND Upper limits
  55. GRB101204A GROND Detection of the Optical/NIR Afterglow
  56. GRB 101201A: GROND Detection of the Optical/NIR Afterglow
  57. GRB 101117B: GROND Upper limits
  58. GRB 101114A: GROND Upper limits
  59. GRB 101030A: GROND optical/NIR afterglow candidate
  60. GRB 101024A: GROND optical/NIR observations
  61. Swift/UVOT observations of GRB101023A
  62. GGRB 101023A: GROND detection of the optical-NIR afterglow
  63. GRB 101011A, GROND upper limits
  64. GRB101008A, GROND detection of a fading afterglow
  65. GRB 100924A: GROND detection of an optical/NIR afterglow
  66. GRB 100902A : Confirmation of afterglow and re-brightening with CFHT r’-band imaging
  67. GRB 100902A: GROND observations; afterglow candidate
  68. GRB 100814A: GROND Detection of the Optical/NIR Afterglow
  69. GRB 100728A: GROND Detection of the NIR Afterglow Candidate
  70. GRB 100728B: GROND Detection of the NIR Afterglow
  71. GRB 100725A: GROND upper limits
  72. GRB 100724A: Swift/UVOT observations
  73. GRB 100724A: fading afterglow seen with GROND
  74. GRB 100724A, GROND detection of an afterglow candidate
  75. GRB 100713A: GROND upper limits
  76. GRB 100628A: GROND optical/NIR observations of the host candidate
  77. GRB100625A: GROND confirmation of constant source
  78. GRB 100621A: IRSF/SIRIUS NIR Observation
  79. GRB 100621A: Swift/UVOT observations
  80. GRB 100621A: VLT/X-shooter redshift
  81. GRB 100621A: GROND observation of bright NIR afterglow
  82. GRB 100615A: GROND observations, upper limits
  83. GRB 100606A: GROND observations
  84. GRB 100528A: GROND detection in all bands
  85. GRB100526B: GROND Upper limits
  86. GRB 100522A: GROND observations, upper limits
  87. GRB 100518A: GROND afterglow observation and photo-z
  88. GRB 100508A: GROND Detection of the optical afterglow
  89. GRB 100504A: GROND Upper limits
  90. GRB 100414A : EVLA Radio Detection
  91. GRB 100414A : WSRT Radio Detection
  92. GRB100425A: Swift/UVOT Upper Limits
  93. GRB 100425A: GROND afterglow observation
  94. GRB 100424A: GROND Upper Limits
  95. GRB 100423A: GROND discovery of afterglow
  96. Radio afterglow detection of GRB 100418A with the EVLA
  97. GRB100418A: REM possible afterglow detection
  98. GRB 100418A: further GROND observations and light curve fit
  99. GRB 100418A PAIRITEL NIR Observations
  100. GRB 100418A: GROND observations; missing author list added

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