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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').
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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"

19565 results found.

  1. GRB 090515: WIYN NIR Upper Limit
  2. GRB 090515: PAIRITEL Upper Limits
  3. GRB 090515: Swift detection of a short burst
  4. GRB 090510, Radio limits
  5. GRB090510: VLT/FORS2 spectroscopic redshift
  6. GRB 090510: GROND observations
  7. GRB 090509, further Swift-BAT refined analysis
  8. GRB 090510B: Fermi GBM detection
  9. GRB 090502: Fermi GBM detection
  10. AGILE detection of GRB 090510
  11. GRB 090510: UVOT refined analysis
  12. GRB 090510: Enhanced Swift-XRT position
  13. GRB 090510: NOT afterglow confirmation
  14. GRB 090510: Fermi GBM detection
  15. GRB 090509, SMARTS optical/IR afterglow observations
  16. GRB 090510: Swift detection of a short hard burst
  17. GRB 090408: optical upper limit
  18. GRB 090509: GROND further analysis and redshift limit
  19. GRB 090509: REM NIR afterglow
  20. GRB 090509: GROND afterglow candidate
  21. GRB 090423: optical limit
  22. GRB 090423: 250 GHz upper limit for a z=8.2 GRB with MAMBO-2 at the IRAM 30m
  23. GRB 080913: 250 GHz upper limit for a z=6.7 GRB with MAMBO-2 at the IRAM 30m
  24. GRB 090427: GROND observations
  25. GRB 090429A: ROVOR magnitude limit
  26. GRB 090424, SMARTS optical/IR afterglow monitoring
  27. GRB 090429D: Fermi GBM detection
  28. GRB 090429C: Fermi GBM detection
  29. GRB 090429B: Swift/UVOT Upper Limits
  30. GRB 090429A: Swift/UVOT Upper Limits
  31. GRB 090429B: Gemini-N further nIR observations
  32. GRB 090429A: GROND upper limits
  33. GRB 090427C: Fermi GBM detection
  34. GRB 090427B: Fermi GBM detection
  35. GRB 090426C: Fermi GBM detection
  36. GRB 090426B: Fermi GBM detection/observation
  37. GRB 090429A: Enhanced Swift-XRT position
  38. Konus-Wind observation of very bright GRB 090427
  39. GRB 090428B: Fermi GBM detection
  40. GRB 090428: Fermi GBM detection
  41. GRB 090418A BVRcIc field calibration
  42. GRB 090429B: RIMOTS optical upper limits
  43. GRB 090429B: Enhanced Swift-XRT position
  44. GRB090429B: Gemini-N infrared IR candidate
  45. GRB 090429B: VLT upper limits
  46. GRB 090429B: GROND Observations
  47. GRB 090429B: Super-LOTIS early observations
  48. GRB 090429B: Swift detection of a burst
  49. GRB 090429: Swift detection of a burst
  50. GRB 090423: pseudo burst at z=1 and its relation to GRB 080913
  51. GRB 090424 : Multiband Optical observation from Nainital
  52. IPN triangulation of very bright GRB 090427
  53. GRB 090423: CARMA mm observations
  54. GRB 090423: millimeter detection
  55. GRB 090425: Fermi GBM detection
  56. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  57. GRB 090423: GROND second epoch imaging and refined SED
  58. Detection of bright radio afterglow of GRB 090424 with the VLA
  59. GRB 090426: Enhanced Swift-XRT position
  60. GRB090426: Observation for Optical counterpart from MIRO
  61. GRB 090426, RIMOTS optical upper limits
  62. GRB 090426: Swift detection of a burst with an optical counterpart
  63. GRB 090424: MASTER-Net prompt optical limit
  64. GRB 090423: Fermi GBM observation (correction of isotropic equivalent energy)
  65. GRB 090424: WHT ISIS spectroscopy
  66. VLA radio observation of high-z GRB 090423
  67. GRB 090424: THO optical observations
  68. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  69. GRB 090423: Y-band field calibration update/correction
  70. GRB 090423: Swift/BAT spectral lag results
  71. GRB 090424 : TAOS optical detection
  72. GRB 090424: Liverpool Telescope observations
  73. GRB 090424: Swift-XRT refined analysis
  74. GRB 090424: Optical observations from 1.23m CAHA
  75. GRB 090423: energetic, luminosity and jet break
  76. GRB 090424: MASTER-Net prompt optical observations
  77. GRB 090424: Enhanced Swift-XRT position
  78. GRB 090424: Fermi GBM Observation
  79. GRB 090423: Fermi GBM observation
  80. GRB 090422: Fermi GBM observation
  81. GRB 090423: Ep,i - Eiso correlation
  82. GRB 090424: Swift detection of a burst with an optical counterpart
  83. GRB090423: Y-band field calibration
  84. GRB 090423 limiting magnitudes
  85. GRB 090423: Near infrared observation at Okayama Observatory
  86. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  87. GRB 090423: GROND detection and preliminary photo-z
  88. GRB 090423: NOT z-band limit
  89. GRB090418A Rc-band photometry
  90. GRB 090423: NIR photometry and evidence for spectral break
  91. GRB090423, RIMOTS optical upper limits
  92. GRB 090423: Enhanced Swift-XRT position
  93. GRB 090422: Swift/UVOT Upper Limits
  94. GRB 090423: UKIRT K-band observations
  95. GRB 090423: P60 Observations
  96. GRB 090418A: R and I band observation
  97. GRB 090423: Swift detection of a burst
  98. GRB 090422: Swift-BAT refined analysis
  99. GRB 090422: Enhanced Swift-XRT position
  100. GRB 090418B: RTT150 optical observations

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