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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.

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

32551 results found.

  1. GRB 090530: RTT150 Optical Observation
  2. GRB 090529A: RTT150 Optical Observations
  3. GMRT observation of GRB 090424 afterglow
  4. GRB 090528: Suzaku WAM observation of the prompt emission
  5. GRB090529: Further NOT optical observations
  6. GRB 090531b, SMARTS optical/IR observations
  7. GRB 090531B: GROND observation
  8. GRB 090530: Early RAPTOR Optical Observations
  9. GRB090529B: ROVOR Upper Limits
  10. GRB 090531A: SARA upper limit
  11. GRB 090531B: Swift/BAT spectral lag results
  12. Corrections to GRB 090531B Swift/UVOT Upper Limits
  13. GRB 090531B, RIMOTS optical upper limits
  14. GRB 090531B: Swift/UVOT Upper Limits
  15. GRB 090528B: MASTER-II Kourovka optical limit
  16. GRB 090529: MITSuME optical observation
  17. GRB 090530: GRT Optical Observation
  18. GRB 090531B: Swift-BAT refined analysis
  19. Initial Swift/UVOT observations of GRB 090531B
  20. GRB 090531B: Swift-XRT candidate afterglow position
  21. GRB 090531B: ROTSE-III Optical Limits
  22. GRB 090531: Swift-BAT refined analysis
  23. GRB090530: R-band Observation
  24. GRB 090530: break in light curve
  25. GRB 090529: VLT spectroscopic redshift
  26. GRB 090531: GROND upper limits
  27. GRB 090531: P60 Observations
  28. GRB 090529: NOT optical observations
  29. GRB 090530: NOT optical observations
  30. GRB090530: Swift XRT refined analysis
  31. GRB090530: Swift/UVOT afterglow detection
  32. GRB 090529: Swift-XRT refined analysis
  33. GRB 090529: OSN optical observations
  34. Strong radio emission from SN 2007bg one year after the explosion - detection of spreading, off-axis GRB jet?
  35. GRB 090530: Swift-BAT refined analysis
  36. GRB 090530: GRAS002 refined OA analysis
  37. GRB 090530: GRAS002 optical observations
  38. GRB 090530: PAIRITEL NIR Detections
  39. GRB 090530A: ROTSE-III Detection of Optical Counterpart
  40. GRB 090529: optical observations
  41. GRB 090529: TLS Afterglow Observations
  42. GRB090529: UVOT/Swift detection of a brightening optical afterglow
  43. GRB 090529: Swift-BAT refined analysis
  44. GRB 090529: Preliminary Swift/UVOT Upper Limit
  45. GRB 090529: Xinglong TNT optical observation
  46. GRB 090520B: Fermi GBM detection
  47. GRB 090518 - NOT upper limit
  48. GRB 090516A: Konus-Wind and Swift/BAT joint spectral analysis
  49. GRB 090520: GROND upper limits
  50. GRB 090518: Fermi GBM detection
  51. GRB 090423: Fermi GBM T90 follow-up analysis results
  52. GRB 090516: Fermi GBM observation
  53. GRB 090519: Swift-XRT refined analysis
  54. GRB 090519: NOT refined analysis
  55. GRB 090519: VLT spectroscopic redshift
  56. GRB 090519: GROND observation
  57. GRB 090519: Swift/UVOT Upper Limits
  58. GRB 090519, Swift-BAT refined analysis
  59. GRB 090519: NOT afterglow candidate
  60. GRB 090518: Swift/UVOT Upper Limits
  61. GRB 090516: Observations from Stardome Observatory
  62. GRB090518: GROND upper limits
  63. GRB 090518: P60 Observations
  64. GRB 090518, Swift-BAT refined analysis
  65. GRB 090516, RIMOTS optical upper limits
  66. GRB090518 : Optical upper limit by MOA-II telescope
  67. GRB 090518: Swift-XRT refined analysis
  68. GRB 090515: Swift/BAT spectral lag results
  69. GRB 090516: Swift-BAT refined analysis
  70. GRB 090516: VLT spectrum (correction & update)
  71. GRB 090516: GROND OBSERVATIONS
  72. GRB 090516: VLT redshift
  73. GRB 090516 - Zadko Telescope observations
  74. GRB 090516: NOT optical observations
  75. GRB 090516: Swift XRT refined analysis
  76. GRB 090516: Swift/UVOT Observations
  77. GRB 090516: Faulkes Telescope South optical afterglow
  78. GRB 090515: Lick Upper Limits
  79. GRB 090515: ROVOR Upper Limit
  80. GRB 090515: MMT/MMIRS NIR Upper Limit
  81. GRB 090515: Swift/UVOT Observations
  82. GRB 090515: Swift-XRT refined analysis
  83. GRB 090509: Fermi GBM observation
  84. GRB 090515: Swift-BAT refined spectral analysis
  85. GRB 090515: Swift-BAT refined analysis
  86. GRB 090509 - Zadko Telescope observations
  87. GRB 090515: Gemini-N upper limit
  88. GRB 090515: WIYN NIR Upper Limit
  89. GRB 090515: Super-LOTIS Upper Limits
  90. GRB 090515: PAIRITEL Upper Limits
  91. GRB 090515: KAIT optical upper limits
  92. GRB 090515: ROTSE-III Optical Limits
  93. GRB 090510: Suzaku WAM observation of the prompt emission
  94. GRB 090510, Radio limits
  95. GRB090510: VLT/FORS2 spectroscopic redshift
  96. GRB 090510: GROND observations
  97. GRB 090510: Swift/UVOT host galaxy candidates
  98. GRB 090510: Fermi-LAT follow-up analysis
  99. GRB 090509, further Swift-BAT refined analysis
  100. GRB 090510: correction to GCN 9344

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