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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"

23578 results found.

  1. GRB 090515: Swift-BAT refined analysis
  2. GRB 090509 - Zadko Telescope observations
  3. GRB 090515: Gemini-N upper limit
  4. GRB 090515: Super-LOTIS Upper Limits
  5. GRB 090515: PAIRITEL Upper Limits
  6. GRB 090515: Swift detection of a short burst
  7. GRB 090510: Suzaku WAM observation of the prompt emission
  8. GRB 090510: GROND observations
  9. GRB 090510: Swift/UVOT host galaxy candidates
  10. GRB 090509, further Swift-BAT refined analysis
  11. Konus-Wind observation of GRB 090510
  12. AGILE detection of GRB 090510
  13. GRB 090510: UVOT refined analysis
  14. GRB 090510: NOT afterglow confirmation
  15. GRB 090510: Swift-BAT refined analysis
  16. GRB 090510: Fermi GBM detection
  17. GRB 090509: Swift-BAT refined analysis
  18. GRB 090510: Swift detection of a short hard burst
  19. GRB 090509: GROND afterglow candidate
  20. GRB 090509: Swift detection of a burst
  21. GRB 090423: 250 GHz upper limit for a z=8.2 GRB with MAMBO-2 at the IRAM 30m
  22. GRB 080913: 250 GHz upper limit for a z=6.7 GRB with MAMBO-2 at the IRAM 30m
  23. GRB 090428B: Suzaku WAM observation of the prompt emission
  24. GRB 090429D: Fermi GBM detection
  25. GRB 090429C: Fermi GBM detection
  26. GRB 090429B: Swift/UVOT Upper Limits
  27. GRB 090429A: Swift/UVOT Upper Limits
  28. GRB 090424: YNAO-GMG observations
  29. GRB 090429A: Swift-XRT refined analysis
  30. GRB 090427C: Fermi GBM detection
  31. GRB 090427B: Fermi GBM detection
  32. GRB 090426C: Fermi GBM detection
  33. GRB 090426B: Fermi GBM detection/observation
  34. Konus-Wind observation of very bright GRB 090427
  35. GRB 090429B: RIMOTS optical upper limits
  36. GRB 090429B: Swift-BAT refined analysis
  37. GRB 090429A: Swift-BAT refined analysis
  38. GRB 090426: YNAO-GMG observations
  39. GRB 090429B: GROND Observations
  40. GRB 090429B: Swift detection of a burst
  41. GRB 090429: Swift detection of a burst
  42. GRB 090424 : Multiband Optical observation from Nainital
  43. IPN triangulation of very bright GRB 090427
  44. GRB 090426: R-band limit
  45. GRB 090424: Continued R-band monitoring
  46. GRB 090423: millimeter detection
  47. GRB 090426: Swift/BAT spectral lag results
  48. GRB 090424: Suzaku WAM observation of the prompt emission
  49. GRB 090426: VLT spectroscopy
  50. GRB 090426: GROND Observations of the Optical/NIR Afterglow
  51. GRB 090426: Near infrared observation with ISLE at OAO
  52. GRB 090426: Okayama MITSuME optical observation
  53. GRB 090426 Keck LRIS redshift
  54. GRB 090426: Swift-BAT refined analysis
  55. GRB 090423: GROND second epoch imaging and refined SED
  56. GRB 090426: Swift detection of a burst with an optical counterpart
  57. GRB090424: R-band detection (37.5 hrs post-burst), jet break?
  58. GRB 090424: MASTER-Net prompt optical limit
  59. GRB090424: BVRI/R-band detection after 15 hrs burst
  60. GRB 090424: GROND Observations of the Optical/NIR Afterglow
  61. GRB090423: Y-band limit
  62. GRB 090423: Y-band field calibration update/correction
  63. GRB 090423: Swift/BAT spectral lag results
  64. GRB 090424: Liverpool Telescope observations
  65. GRB 090424: Optical observations from 1.23m CAHA
  66. GRB 090423: energetic, luminosity and jet break
  67. GRB 090424: MASTER-Net prompt optical observations
  68. GRB 090424: Swift-BAT refined analysis
  69. GRB 090424: Fermi GBM Observation
  70. GRB 090422: Fermi GBM observation
  71. GRB 090424: ROTSE-III Confimation of Optical Counterpart
  72. GRB 090424: Swift detection of a burst with an optical counterpart
  73. GRB 090423: Refined TNG analysis
  74. GRB090423: Y-band field calibration
  75. GRB 090423: Near infrared observation at Okayama Observatory
  76. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  77. GRB 090423: TNG Amici spectrum
  78. GRB 090423: Swift-XRT refined analysis
  79. GRB090423 - Swift/UVOT upper limits.
  80. GRB 090422: Swift-XRT refined analysis
  81. GRB090423, RIMOTS optical upper limits
  82. GRB 090423: Swift-BAT refined analysis
  83. GRB 090423: Faulkes Telescope South observations
  84. GRB 090423: Swift detection of a burst
  85. GRB 090418A: Konus-Wind and Swift/BAT joint spectral analysis
  86. GRB 090422: Swift-BAT refined analysis
  87. GRB 090418B: RTT150 optical observations
  88. GRB 090418A: RTT150 optical observations
  89. GRB 090422: Liverpool Telescope observations
  90. GRB 090418B: Suzaku WAM observation of the prompt emission
  91. GRB 090422: Swift detection of a burst
  92. GRB 090418C: Fermi GBM Detection
  93. Swift-BAT trigger 349718 is not a burst
  94. GRB 090419: Swift/UVOT Observations
  95. GRB 090418B: Faulkes Telescope North observations
  96. GRB 090419: Swift-XRT refined analysis
  97. Konus-Wind observation of GRB 090418B
  98. GRB 090418: Erratum in GCN 9168
  99. GRB 090418: Optical observations with MITSuME Okayama and Ishigaki 1m telescope
  100. GRB 090419: Swift-BAT refined analysis

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