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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"

12320 results found.

  1. GRB 131018A: KAIT Optical Upper Limit
  2. GRB 131018A: P60 Observations
  3. GRB 131018A: Swift detection of a burst
  4. GRB 131014A: GROND observations
  5. GRB 131014A: RATIR Optical/NIR Afterglow Confirmation
  6. GRB 131011A: Swift/UVOT Upper Limits
  7. GRB 131014A: Swift/UVOT Upper Limits
  8. Fermi403206457: Weihai optical upper limit
  9. Trigger 574266 is not a Swift detection of a known source
  10. GRB 130831A: Continued RATIR Optical and NIR Observations
  11. GRB 131004A: Skynet PROMPT/DSO-14 upper limits
  12. GRB 131004A: CARMA 93 GHz upper limit
  13. GRB 131004A: Swift/UVOT Detection
  14. GRB 131004A: RATIR Optical and NIR Upper Limits
  15. GRB 131002B: GROND upper limits
  16. GRB 131002B: Swift/UVOT Upper Limits
  17. GRB 131002A: Swift/UVOT Detection
  18. Swift J1242.9-3530, Swift-BAT refined analysis
  19. GRB 131001A: Swift UVOT and XRT Upper Limits
  20. GRB 131002B: Swift detection of a burst
  21. GRB 131002A: Swift detection of a burst
  22. GRB 130929A: Swift/UVOT Upper Limits
  23. GRB 130831A: Continued RATIR Optical and NIR Observations
  24. Fermi LAT Upper Limits on GRB 130925A
  25. GRB 130925A: Swift/UVOT Upper Limits
  26. GRB 130925A: optical upper limit
  27. GRB 130925A: Continued RATIR Optical and NIR Observations
  28. Observation of possible GRB/TDE 130925A by INTEGRAL/SPI-ACS: three activity episodes
  29. GRB 130925A: RATIR Optical and NIR Observations
  30. GRB 130925A: Historical non-detection from Rosat-HRI
  31. GRB 130925A: TAROT La Silla observatory optical observations
  32. GRB 130925A: MAXI/GSC detection
  33. GRB 130925A: Swift detection of a burst
  34. GRB 130831A: RATIR Confirmation of NIR/Optical Afterglow Flattening
  35. GRB 130912A: AAO optical upper limit
  36. Fermi Trigger 401326696: MASTER prompt optical observations
  37. GRB 130919A: Skynet PROMPT-CTIO optical upper limits
  38. GRB 130903A: Further Swift XRT observations.
  39. GRB 130912A: Swift/UVOT Upper Limits
  40. GRB 130912A: 5.8 GHz VLA upper limit
  41. GRB 130912A: RATIR Optical and NIR Upper Limits
  42. GRB 130907A: Continued RATIR Optical and NIR Observations
  43. GRB 130907A: MASTER refined analysis
  44. GRB 130912A: REM optical/NIR upper limits
  45. GRB 130912A: KAIT optical upper limit
  46. GRB 120419A: Swift XRT confirmation of the afterglow
  47. GRB 130907A: Continued RATIR Optical and NIR Observations
  48. GRB 130907A: RATIR Optical and NIR Observations
  49. GRB 130828A: Further Swift XRT observations
  50. GRB 130907A: INTEGRAL/SPI-ACS light curve
  51. GRB 130907A: Swift/UVOT Detection
  52. Swift follow-up results of the possible weak INTEGRAL GRB
  53. GRB 130903A: Swift/UVOT Upper Limits
  54. Swift follow-up of an INTEGRAL possible weak GRB
  55. GRB 130831A: RATIR Optical and NIR Upper Limits
  56. GRB 130903A: MASTER early optical limit
  57. GRB 130903A: Swift-XRT observations
  58. GRB 130903A: ISON-Kislovodsk optical Upper Limits
  59. GRB 130903A: GROND Upper Limits
  60. GRB 130831A: Swift/UVOT Observations
  61. GRB 130831A: VLA Observations
  62. GRB 130831B: Swift/UVOT Upper Limits
  63. GRB 130831A: CARMA mm upper limit
  64. GRB 130831B: GROND upper limits
  65. GRB 130831B: Swift detection of a burst
  66. GRB 130822A: optical upper limits
  67. GRB 130821A: Weihai optical upper limit
  68. GRB 130821A: Swift-XRT observation
  69. GRB 130822A: 5.8 GHz VLA upper limit
  70. GRB 130822A: Gemini Observations
  71. GRB 130822A: WHT ACAM observations
  72. GRB 130822A: Swift/UVOT Upper Limits
  73. GRB 130822A: Weihai optical upper limit
  74. GRB 130822A: Swift detection of a short burst
  75. GRB 130816A: Swift/UVOT Upper Limits
  76. GRB 130816B: Swift/UVOT Upper Limits
  77. GRB 130816B: Swift detection of a burst
  78. GRB 130816A: Swift detection of a burst
  79. GRB 130812A: Swift/UVOT Upper Limits
  80. GRB 130812A: GROND upper limits
  81. GRB 130812A: Swift detection of a burst
  82. GRB130807A: Swift/UVOT observations
  83. GRB 130806A: Swift/UVOT Upper Limits
  84. GRB 130807A: Swift detection of a GRB or Galactic transient
  85. GRB 130623A: GROND detection of the optical/NIR afterglow
  86. GRB 130806A: MITSuME Akeno Optical observation
  87. GRB 130806A: MITSuME Okayama upper limits
  88. GRB 130806A: Swift detection of a burst
  89. GRB 130803A: RATIR Optical and NIR Observations
  90. GRB 130803A: Swift/UVOT Upper Limits
  91. GRB 130803A: Faulkes Telescope South Observations
  92. GRB 130727A: Swift/UVOT Detection
  93. GRB 130725B: Swift/UVOT Observations
  94. GRB 130725A: Swift/UVOT Upper Limits
  95. GRB 130725A: MITSuME Ishigakijima Optical Observation
  96. Swift Trigger 563980 is GRB 130725A
  97. GRB 130702A in the Ep,i - Eiso plane
  98. GRB 130722A: Swift/UVOT Detection
  99. GRB 130722A: MITSuME Okayama upper limits
  100. GRB 130722A: Swift detection of a burst

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