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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"

12321 results found.

  1. GRB 090429B: Swift/UVOT Upper Limits
  2. GRB 090429A: Swift/UVOT Upper Limits
  3. GRB 090429A: GROND upper limits
  4. Konus-Wind observation of very bright GRB 090427
  5. GRB 090429B: RIMOTS optical upper limits
  6. GRB 090429B: VLT upper limits
  7. GRB 090429B: GROND Observations
  8. GRB 090429B: Swift detection of a burst
  9. GRB 090429: Swift detection of a burst
  10. GRB 090426: R-band limit
  11. GRB 090423: CARMA mm observations
  12. GRB090426 Swift/UVOT observations
  13. GRB 090426: Swift-XRT refined analysis
  14. GRB 090423: GROND second epoch imaging and refined SED
  15. GRB 090426, RIMOTS optical upper limits
  16. GRB 090424: WHT ISIS spectroscopy
  17. VLA radio observation of high-z GRB 090423
  18. GRB 090424: THO optical observations
  19. GRB090423: Y-band limit
  20. Swift/UVOT observations of GRB 090424
  21. GRB 090423: Deep z-band upper limit and confirmation of photo-z
  22. GRB 090423: GROND detection and preliminary photo-z
  23. GRB090423 - Swift/UVOT upper limits.
  24. GRB090423, RIMOTS optical upper limits
  25. GRB 090422: Swift/UVOT Upper Limits
  26. GRB 090418A: R and I band observation
  27. GRB 090423: Swift detection of a burst
  28. GRB 090418B: RTT150 optical observations
  29. GRB 090422: Swift detection of a burst
  30. GRB 090418B: GRAS002 observatios
  31. GRB 090417B: Optical observation
  32. GRB 090418B: GROND observations
  33. GRB 090419: Swift/UVOT Observations
  34. GRB 090418A: Swift/UVOT Observations
  35. GRB 090417B: Swift/UVOT Upper Limits
  36. Konus-Wind observation of GRB 090418B
  37. GRB 090419: GROND detection of afterglow candidate
  38. GRB 090418: Optical observations with MITSuME Okayama and Ishigaki 1m telescope
  39. VLA radio upper limit on GRB 090417B
  40. GRB 090419: Swift detection of a burst
  41. GRB 090417B: MITSuME Okayama optical upper limits
  42. GRB090417B: Xinglong TNT optical upper limit
  43. GRB 090417B: Swift detection of a burst
  44. GRB 090410: GROND upper limits
  45. GRB 090410: MITSuME optical upper limits
  46. GRB090408, RIMOTS optical upper limits
  47. GRB 090408: Xinglong TNT optical Upper Limit
  48. Swift-BAT trigger 348781: almost certainly not a burst
  49. GRB 090407: GROND upper limits
  50. GRB 090407: Swift UVOT Upper Limits
  51. GRB 090407: Swift detection of a burst
  52. GRB 090404: GROND upper limits
  53. Swift/UVOT observations of GRB090404
  54. GRB 090404: Xinglong TNT optical Upper Limit
  55. GRB 090404: Swift detection of a burst
  56. GRB 090401B: Xinglong TNT optical Upper Limit
  57. GRB 090401B: VLA radio upper limit
  58. GRB 090401B: Upper limits of MITSuME optical observation
  59. GRB090401B, RIMOTS optical upper limits
  60. Swift/UVOT observations of GRB090401B
  61. Swift/UVOT observations of GRB090401B
  62. Konus-Wind observation of GRB 090401A
  63. GRB 090401B: Swift detection of a burst
  64. GRB 090323: UVOT Detection of Afterglow
  65. GRB 090323: Swift-XRT refined analysis
  66. Further Swift/UVOT observations of GRB 090313
  67. GRB 090313: Swift/UVOT upper limits
  68. GRB 090306B: Confirmation of the X-ray afterglow
  69. GRB 090309A: GROND upper limits
  70. GRB 090309: Swift/UVOT Upper Limits
  71. GRB 090306B: INTEGRAL SPI-ACS light curve
  72. GRB 090309: Swift detection of a burst
  73. GRB 090308: Swift/UVOT Upper Limits
  74. GRB 090307: GROND Upper Limits
  75. GRB 090306B: GROND Upper Limits
  76. Swift Trigger 345551 is probably not a GRB
  77. GRB 090305: Swift/UVOT Upper Limits
  78. GRB 090305: Swift-XRT refined analysis
  79. SGR J1550-5418
  80. GRB 090217: Suzaku WAM observation of the prompt emission
  81. VLA radio upper limit on GRB 090205
  82. GRB 090205: Swift/UVOT Upper Limits
  83. GRB 090205: Swift-XRT refined analysis
  84. GRB 080319B: IceCube upper limit on high-energy neutrino flux
  85. ICSP VLF observation of the signatures of SGR/AXP 1E1547.0-5408 bursts
  86. GRB090201: Swift UVOT upper limits
  87. GRB 090201: VLT NIR observations
  88. GRB090113: MAGIC telescope GeV observation
  89. GRB 090126A: Swift/UVOT Upper Limits
  90. GRB 090118: no afterglow candidate
  91. GRB 090123: GROND detection
  92. AXP 1E1547.0-5408: INTEGRAL SPI-ACS confirms activity increase
  93. Trigger 340734: Swift detection of a possible short burst
  94. GRB 090118 (BATSS): GRT Optical Observation
  95. GRB 090118: Swift-XRT observations
  96. GRB090118 Swift/UVOT upper limits
  97. GRB 090118: GROND Upper Limits
  98. GRB 090117: GROND Upper Limits
  99. GRB090117 Swift/UVOT upper limits
  100. GRB090102: MAGIC telescope GeV observation

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