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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19093 results found.

  1. GRB 090511: Fermi GBM Detection
  2. GRB 090514: Fermi GBM detection
  3. GRB 090518: Swift/UVOT Upper Limits
  4. GRB 090516: Observations from Stardome Observatory
  5. GRB090518: GROND upper limits
  6. GRB 090518: P60 Observations
  7. GRB 090518B: Fermi GBM detection
  8. GRB 090516, RIMOTS optical upper limits
  9. GRB090513: Fermi GBM detection
  10. GRB 090518: Enhanced Swift-XRT position
  11. GRB 090518: Swift detection of a burst
  12. GRB 090516: GROND OBSERVATIONS
  13. GRB 090516 - Zadko Telescope observations
  14. GRB 090516: NOT optical observations
  15. GRB 090516: Swift/UVOT Observations
  16. GRB 090516: Enhanced Swift-XRT position
  17. GRB 090516: Swift detection of a burst
  18. GRB 090515: VLA observations
  19. GRB 090515: Lick Upper Limits
  20. GRB 090515: ROVOR Upper Limit
  21. GRB 090515: MMT/MMIRS NIR Upper Limit
  22. GRB 090515: Swift/UVOT Observations
  23. GRB 090515: Enhanced Swift-XRT position
  24. GRB 090509: Fermi GBM observation
  25. GRB 090515: Swift-BAT refined spectral analysis
  26. GRB 090515: Swift-BAT refined analysis
  27. GRB 090509 - Zadko Telescope observations
  28. GRB 090515: Gemini-N upper limit
  29. GRB 090515: WIYN NIR Upper Limit
  30. GRB 090515: PAIRITEL Upper Limits
  31. GRB 090515: Swift detection of a short burst
  32. GRB 090510, Radio limits
  33. GRB090510: VLT/FORS2 spectroscopic redshift
  34. GRB 090510: GROND observations
  35. GRB 090509, further Swift-BAT refined analysis
  36. GRB 090510B: Fermi GBM detection
  37. GRB 090502: Fermi GBM detection
  38. AGILE detection of GRB 090510
  39. GRB 090510: UVOT refined analysis
  40. GRB 090510: Enhanced Swift-XRT position
  41. GRB 090510: NOT afterglow confirmation
  42. GRB 090510: Fermi GBM detection
  43. GRB 090509, SMARTS optical/IR afterglow observations
  44. GRB 090510: Swift detection of a short hard burst
  45. GRB 090408: optical upper limit
  46. GRB 090509: GROND further analysis and redshift limit
  47. GRB 090509: REM NIR afterglow
  48. GRB 090509: GROND afterglow candidate
  49. GRB 090423: optical limit
  50. GRB 090423: 250 GHz upper limit for a z=8.2 GRB with MAMBO-2 at the IRAM 30m
  51. GRB 080913: 250 GHz upper limit for a z=6.7 GRB with MAMBO-2 at the IRAM 30m
  52. GRB 090427: GROND observations
  53. GRB 090429A: ROVOR magnitude limit
  54. GRB 090424, SMARTS optical/IR afterglow monitoring
  55. GRB 090429D: Fermi GBM detection
  56. GRB 090429C: Fermi GBM detection
  57. GRB 090429B: Swift/UVOT Upper Limits
  58. GRB 090429A: Swift/UVOT Upper Limits
  59. GRB 090429B: Gemini-N further nIR observations
  60. GRB 090429A: GROND upper limits
  61. GRB 090427C: Fermi GBM detection
  62. GRB 090427B: Fermi GBM detection
  63. GRB 090426C: Fermi GBM detection
  64. GRB 090426B: Fermi GBM detection/observation
  65. GRB 090429A: Enhanced Swift-XRT position
  66. Konus-Wind observation of very bright GRB 090427
  67. GRB 090428B: Fermi GBM detection
  68. GRB 090428: Fermi GBM detection
  69. GRB 090418A BVRcIc field calibration
  70. GRB 090429B: RIMOTS optical upper limits
  71. GRB 090429B: Enhanced Swift-XRT position
  72. GRB090429B: Gemini-N infrared IR candidate
  73. GRB 090429B: VLT upper limits
  74. GRB 090429B: GROND Observations
  75. GRB 090429B: Super-LOTIS early observations
  76. GRB 090429B: Swift detection of a burst
  77. GRB 090429: Swift detection of a burst
  78. GRB 090423: pseudo burst at z=1 and its relation to GRB 080913
  79. GRB 090424 : Multiband Optical observation from Nainital
  80. IPN triangulation of very bright GRB 090427
  81. GRB 090423: CARMA mm observations
  82. GRB 090423: millimeter detection
  83. GRB 090425: Fermi GBM detection
  84. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  85. GRB 090423: GROND second epoch imaging and refined SED
  86. Detection of bright radio afterglow of GRB 090424 with the VLA
  87. GRB 090426: Enhanced Swift-XRT position
  88. GRB090426: Observation for Optical counterpart from MIRO
  89. GRB 090426, RIMOTS optical upper limits
  90. GRB 090426: Swift detection of a burst with an optical counterpart
  91. GRB 090424: MASTER-Net prompt optical limit
  92. GRB 090423: Fermi GBM observation (correction of isotropic equivalent energy)
  93. GRB 090424: WHT ISIS spectroscopy
  94. VLA radio observation of high-z GRB 090423
  95. GRB 090424: THO optical observations
  96. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  97. GRB 090423: Y-band field calibration update/correction
  98. GRB 090423: Swift/BAT spectral lag results
  99. GRB 090424 : TAOS optical detection
  100. GRB 090424: Liverpool Telescope observations

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