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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"

25028 results found.

  1. GRB 070420: optical rebrightening observed at Mt. John
  2. GRB070420: Swift UVOT continuing observations
  3. GRB 070420: Faulkes Telescope South Observations
  4. GRB 070420: TAROT La Silla observatory optical observations
  5. GRB 070420: NIR and optical afterglow confirmed
  6. GRB 070420: Swift detection of a burst with optical afterglow
  7. GRB 070419A: MITSuME Okayama Observations
  8. GRB 070419A: Early Super-LOTIS Observations
  9. GRB 070419B, Swift-BAT refined analysis
  10. GRB 070419A Swift-BAT Refined Analysis
  11. GRB 070419A, Optical observations
  12. GRB070419 - SDSS Pre-Burst Observations
  13. GRB 070419A: SARA observations
  14. GRB 070419A: NAYUTA Optical Observation
  15. GRB 070419B optical afterglow candidate
  16. GRB 070419A: Optical and IR observations with KANATA
  17. GRB 070419B: optical afterglow candidate
  18. GRB070419A, optical observation
  19. Infrared detection of GRB070419A with UKIRT
  20. GRB 070419A: Kiso Optical observation
  21. GRB 070419: P60 Confirmation of Optical Afterglow
  22. GRB 070419B: Swift detection of a burst
  23. GRB 070419A: ROTSE-III Optical Limits
  24. GRB 070419: Swift detection of a burst
  25. GRB 070418: Optical and IR observations with KANATA
  26. Trigger 276045: Swift detection of a possible burst
  27. GRB 070406: Swift XRT refined analysis
  28. GRB070412: UKIRT-WFCAM JHK upper limits
  29. GRB070412: Swift UVOT observations
  30. GRB 070411: Swift/UVOT observations
  31. GRB 070412, Swift-BAT refined analysis
  32. GRB 070412 Liverpool Telescope optical limit
  33. GRB 070412: Optical observations at Crni Vrh
  34. GRB 070412: further NOT observations
  35. GRB 070412: Gemini/GMOS afterglow candidate
  36. GRB 070412: IAC80 optical afterglow candidate
  37. GRB 070412: NOT observations
  38. GRB 070411, Swift-BAT refined analysis
  39. GRB 070412: Swift detection of a burst
  40. GRB 070411: IAC80 optical observations
  41. GRB 070411 : Liverpool Telescope Observations
  42. GRB 070411: Swift detection of a burst with optical afterglow
  43. GRB 070406: Swift XRT team further analysis
  44. Suzaku ToO observation of SGR 1806-20
  45. GRB 070406: Astrometrically Refined XRT Position, Unfading Source
  46. GRB 070406, Swift-BAT refined analysis
  47. GRB 070406: Correction to the optical candidate in GCN6253
  48. GRB 070406: Gemini South Imaging and XRT analysis
  49. GRB070406: Swift UVOT observations
  50. GRB 070406: further analysis of NOT images.
  51. Short GRB 070406 - Possible Bright Host Galaxy
  52. GRB 070406: NOT observations
  53. GRB 070406: Optical candidate
  54. GRB 070406: SARA upper limit
  55. GRB 070406: Xinglong TNT optical Upper Limit
  56. GRB 070402: Suzaku WAM observation of the prompt emission
  57. GRB 070328: Suzaku WAM observation of the prompt emission
  58. UVOT observations of GRB070330
  59. GRB 070330, Swift-BAT refined analysis
  60. GRB 070330: TAROT La Silla observatory optical observations
  61. GRB 070330 - Watcher Observations
  62. GRB 070330: Swift detection of a burst
  63. GRB 070328: Swift/UVOT Upper Limits
  64. long burst from SGR 1806-20 detected on March 26
  65. GRB 070328: Swift/XRT Refined Analysis
  66. GRB 070328 : Suzaku ToO follow up starts
  67. GRB 070328, Swift-BAT refined analysis
  68. GRB 070328: Swift detection of a burst
  69. GRB 070311, deep optical photometry
  70. Short-Hard GRB 070209: PROMPT Observations
  71. GRB 070318: absorption-line redshift
  72. GRB070318: Swift UVOT continuing observations
  73. GRB 070318, Swift-BAT refined analysis
  74. GRB 070318: Swift detection of a burst with an optical afterglow
  75. GRB 070311: Late Central Engine Activity Optical Flare??
  76. VLA observation of GRB 070311
  77. GRB 070311: Optical observation.
  78. GRB 070306: possible emission-line redshift
  79. GRB 070311: SARA upper limit
  80. GRB 070309: variability of the XRT afterglow candidate
  81. GRB070311: FRAM early follow-up limit
  82. GRB 070311: P60 Observations
  83. GRB 070311: Swift/UVOT Upper Limits
  84. GRB 070311: MITSuME Okayama Optical Observation
  85. GRB 070311: Swift-XRT refined analysis
  86. GRB 070311: PAIRITEL confirmation of variability of REM candidate
  87. GRB 070311: REM candidate afterglow
  88. GRB 070311: a long GRB detected by INTEGRAL
  89. GRB060901: Candidate optical afterglow
  90. GRB 070125: Chandra X-ray Confirmation of Jet Break
  91. GRB 070309: Swift/UVOT Upper Limits
  92. GRB 070306, optical observation
  93. Swift UVOT Finding Charts for GRB 070309
  94. GRB 070309: A long GRB detected by INTEGRAL
  95. GRB 070125: X-ray light curve analysis
  96. VLA observation of GRB 070306
  97. GRB 070306: NOT observations
  98. GRB 070306 Swift/UVOT refined analysis
  99. GRB 070306: IR observations and candidate afterglow
  100. GRB 070306, Swift-BAT refined analysis

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