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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"

18467 results found.

  1. GRB 090530: Swift detection of a burst with an optical counterpart
  2. GRB090529: UVOT/Swift detection of a brightening optical afterglow
  3. GRB 090529: Swift-BAT refined analysis
  4. GRB 090529: Enhanced Swift-XRT position
  5. GRB 090529: Preliminary Swift/UVOT Upper Limit
  6. GRB 090529: Swift detection of a burst
  7. GRB 090518 - NOT upper limit
  8. GRB 090520: GROND upper limits
  9. GRB 090518: Fermi GBM detection
  10. GRB 090519: NOT refined analysis
  11. GRB 090519: GROND observation
  12. GRB 090519: Swift/UVOT Upper Limits
  13. GRB 090519: Enhanced Swift-XRT position
  14. GRB 090519: NOT afterglow candidate
  15. GRB 090519: FARO Chante Perdrix Observatory optical observations
  16. GRB 090519: TAROT Calern observatory optical observations
  17. GRB 090519: Swift detection of a burst
  18. GRB 090518: Swift/UVOT Upper Limits
  19. GRB 090516: Observations from Stardome Observatory
  20. GRB090518: GROND upper limits
  21. GRB 090518: P60 Observations
  22. GRB 090516, RIMOTS optical upper limits
  23. GRB 090518: Enhanced Swift-XRT position
  24. GRB 090518: Swift detection of a burst
  25. GRB 090516: Swift-BAT refined analysis
  26. GRB 090516: GROND OBSERVATIONS
  27. GRB 090516 - Zadko Telescope observations
  28. GRB 090516: NOT optical observations
  29. GRB 090516: Swift/UVOT Observations
  30. GRB 090516: Enhanced Swift-XRT position
  31. GRB 090516: Swift detection of a burst
  32. GRB 090515: VLA observations
  33. GRB 090515: Lick Upper Limits
  34. GRB 090515: ROVOR Upper Limit
  35. GRB 090515: MMT/MMIRS NIR Upper Limit
  36. GRB 090515: Swift/UVOT Observations
  37. GRB 090515: Enhanced Swift-XRT position
  38. GRB 090509 - Zadko Telescope observations
  39. GRB 090515: Gemini-N upper limit
  40. GRB 090515: WIYN NIR Upper Limit
  41. GRB 090515: PAIRITEL Upper Limits
  42. GRB 090515: Swift detection of a short burst
  43. GRB 090510, Radio limits
  44. GRB090510: VLT/FORS2 spectroscopic redshift
  45. GRB 090510: GROND observations
  46. GRB 090509, further Swift-BAT refined analysis
  47. AGILE detection of GRB 090510
  48. GRB 090510: UVOT refined analysis
  49. GRB 090510: Enhanced Swift-XRT position
  50. GRB 090510: NOT afterglow confirmation
  51. GRB 090509, SMARTS optical/IR afterglow observations
  52. GRB 090510: Swift detection of a short hard burst
  53. GRB 090509: GROND further analysis and redshift limit
  54. GRB 090509: REM NIR afterglow
  55. GRB 090509: GROND afterglow candidate
  56. GRB 090423: 250 GHz upper limit for a z=8.2 GRB with MAMBO-2 at the IRAM 30m
  57. GRB 080913: 250 GHz upper limit for a z=6.7 GRB with MAMBO-2 at the IRAM 30m
  58. GRB 090427: GROND observations
  59. GRB 090429A: ROVOR magnitude limit
  60. GRB 090424, SMARTS optical/IR afterglow monitoring
  61. GRB 090429B: Swift/UVOT Upper Limits
  62. GRB 090429A: Swift/UVOT Upper Limits
  63. GRB 090429B: Gemini-N further nIR observations
  64. GRB 090429A: GROND upper limits
  65. GRB 090429A: Enhanced Swift-XRT position
  66. GRB 090418A BVRcIc field calibration
  67. GRB 090429B: RIMOTS optical upper limits
  68. GRB 090429B: Enhanced Swift-XRT position
  69. GRB090429B: Gemini-N infrared IR candidate
  70. GRB 090429B: VLT upper limits
  71. GRB 090429B: GROND Observations
  72. GRB 090429B: Super-LOTIS early observations
  73. GRB 090429B: Swift detection of a burst
  74. GRB 090429: Swift detection of a burst
  75. GRB 090424 : Multiband Optical observation from Nainital
  76. IPN triangulation of very bright GRB 090427
  77. GRB 090423: CARMA mm observations
  78. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  79. GRB 090423: GROND second epoch imaging and refined SED
  80. Detection of bright radio afterglow of GRB 090424 with the VLA
  81. GRB 090426: Enhanced Swift-XRT position
  82. GRB090426: Observation for Optical counterpart from MIRO
  83. GRB 090426, RIMOTS optical upper limits
  84. GRB 090426: Swift detection of a burst with an optical counterpart
  85. GRB 090424: MASTER-Net prompt optical limit
  86. VLA radio observation of high-z GRB 090423
  87. GRB 090424: THO optical observations
  88. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  89. GRB 090423: Y-band field calibration update/correction
  90. GRB 090424 : TAOS optical detection
  91. GRB 090424: Liverpool Telescope observations
  92. GRB 090424: Optical observations from 1.23m CAHA
  93. GRB 090424: MASTER-Net prompt optical observations
  94. GRB 090424: Enhanced Swift-XRT position
  95. GRB 090424: Swift detection of a burst with an optical counterpart
  96. GRB090423: Y-band field calibration
  97. GRB 090423 limiting magnitudes
  98. GRB 090423: Near infrared observation at Okayama Observatory
  99. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  100. GRB 090423: GROND detection and preliminary photo-z

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