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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 131002B: GROND upper limits
  2. GRB 130925A: Swift/UVOT Detection of the Host Galaxy
  3. GRB 130925A: Swift/UVOT Upper Limits
  4. GRB 130925A: VLT/UVES observations
  5. GRB 130925A: GROND afterglow candidate
  6. GRB 130912A: P60 Observations
  7. GRB 130912A: GROND observations
  8. GRB 130903A: Swift/UVOT Upper Limits
  9. GRB 130903A: GROND Afterglow Discovery
  10. GRB 130903A: GROND Upper Limits
  11. GRB 130831B: GROND upper limits
  12. GRB 130816B: Swift/UVOT Upper Limits
  13. GRB 130816B: GROND afterglow candidate
  14. GRB 130816A: GROND confirmation of afterglow
  15. GRB 130812A: GROND upper limits
  16. GRB 130623A: GROND detection of the optical/NIR afterglow
  17. GRB130803A: GROND observations
  18. GRB130803A: GROND detection of possible host
  19. GRB 130727A: GROND observations
  20. GRB 130725B: GROND Detection of the Optical/NIR Afterglow
  21. GRB 130615A: Skynet/PROMPT Observations
  22. GRB 130615A: GROND afterglow candidate
  23. GRB 130609B: GROND observations
  24. GRB 130606A: GROND Detection of the Optical/NIR Afterglow
  25. GRB 130605A: GROND afterglow candidate
  26. GRB 130529A: GROND upper limits
  27. GRB 130515A: IRSF NIR Observation
  28. GRB 130515A: Swift/UVOT Upper Limits
  29. GRB 130514B: GROND observations
  30. GRB 130515A: GROND Observations
  31. GRB 130514A: Skynet/PROMPT/DSO Detections
  32. GRB 130514A: Swift/UVOT Upper Limits
  33. GRB 130513A: GROND observations
  34. GRB 130514A: GROND optical-NIR afterglow discovery and photo-z
  35. GRB 100728A: GROND host detection and X-shooter redshift
  36. GRB 130418A: RATIR Optical and NIR Observations
  37. GRB 130418A: GROND detection of the optical-NIR afterglow
  38. GRB 130408A: GROND detection of the afterglow
  39. GRB 130211A: Retraction of afterglow candidate
  40. GRB 130315A: GROND afterglow candidate
  41. GRB 130215A: GROND Detection of the Optical/NIR Afterglow
  42. GRB 130211A: GROND detection of the afterglow
  43. GRB 130206A: GROND Observations
  44. GRB 130131B: GROND Upper limits
  45. GRB 121229A: GROND detection of the afterglow
  46. GRB 121217A: Swift/UVOT Detection
  47. GRB 121217A: GROND Detection of the Afterglow
  48. GRB 121209A: Keck observations
  49. GRB 121209A: CARMA 3mm Observations
  50. GRB 121209A: GROND optical afterglow candidate
  51. GRB 121201A: GROND afterglow observations and photometric redshift
  52. GRB 121123A: GROND observations
  53. GRB 121117A: GROND confirmation of the UVOT afterglow candidate
  54. GRB 121027A: GROND Confirmation of Rebrightening
  55. GRB 121024A: GROND Detection of the Optical/NIR Afterglow
  56. GRB 121017A: GROND Observations
  57. GRB 121001A: GROND Afterglow Confirmation
  58. GRB 120927A: GROND upper limits
  59. GRB 120923A: GROND Upper limits
  60. GRB 120922A: GROND photometric redshift
  61. GRB 120922A: Swift/UVOT Detection
  62. GRB 120922A: GROND afterglow candidate
  63. GRB 120909A: GROND detection of the afterglow
  64. GRB 120821A: GROND upper limits
  65. GRB 120819A: GROND afterglow confirmation
  66. GRB 120815A: VLT/X-shooter redshift
  67. GRB 120815A: GROND afterglow candidate
  68. GRB 120714B: GROND/FORS2 detection of a supernova
  69. GRB 120804A: GROND upper limits
  70. GRB 120728A: GROND Afterglow discovery
  71. GRB 120728A: GROND observations
  72. GRB 120722A: GROND detection of the afterglow
  73. GRB 120716A: GROND confirmation of the optical/NIR afterglow
  74. GRB 120714A: GROND upper limits
  75. GRB 120714B: GROND confirmation of fading afterglow
  76. GRB 120712A: Swift/UVOT Detection
  77. GRB 120712A: GROND Detection of the Optical/NIR Afterglow Candidate and photo-z
  78. GRB 120711A: GROND photometric redshift
  79. GRB 120709A: optical afterglow limits
  80. GRB 120701A: Swift/UVOT Detection
  81. GRB 120701A: GROND detection of the afterglow
  82. Watcher follow-up observations of IGR J17062-6143 (Swift trigger 525148)
  83. GRB 120624B: GROND upper limits
  84. GRB 120521A: GROND Upper limits
  85. GRB 120521B: GROND Upper limits
  86. GRB 120514A: GROND upper limits
  87. GRB 120422A GROND observations
  88. GRB120404A: GROND observations show steeply decaying afterglow
  89. GRB 120401A: GROND Detection of an optical/NIR afterglow candidate
  90. GRB 120327A: X-shooter redshift
  91. GROND observations of GRB 120327A
  92. GRB 120324A: GROND observations
  93. GROND observations of GRB 120311A
  94. GRB 120302A: RTT150 optical observations
  95. GRB 120302A: Swift-BAT refined position and a possible XRT and UVOT counterpart
  96. GRB 120302A: GROND detection of an afterglow candidate
  97. GRB 120224A: GROND detection of the afterglow candidate
  98. GRB 120211A: GROND Upper limits
  99. GRB 120202A: GROND observations
  100. GRB 120119A: GROND Detection of the Optical/NIR Afterglow

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