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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"

32510 results found.

  1. GRB 070805: UVOT afterglow candidate retraction
  2. GRB070810b: optical candidate
  3. GRB 070810A: ROTSE-III Refined Analysis
  4. GRB 061110A: redshift confirmed
  5. GRB 070810B : Faulkes Telescope South Observations
  6. GRB 070810A: Continued Keck Imaging
  7. GRB 070810B: Keck spectroscopy of possible host galaxies
  8. GRB070810B: Swift/UVOT Upper Limits
  9. GRB 070810B: XRT refined analysis
  10. GRB 070810B, Swift-BAT refined analysis
  11. GRB 070809: Swift/UVOT Corrected Photometry
  12. Swift Trigger 287421: False trigger due to star tracker loss
  13. GRB 070810A: Swift-BAT refined analysis
  14. GRB 070810B: Xinglong TNT optical Upper Limit
  15. GRB070810B: Optical observations with KANATA
  16. GRB 070809: Swift/UVOT Upper Limits
  17. VLA upper limit on the short hard burst GRB 070729
  18. GRB 070810: Keck redshift and photometry
  19. No radio detection in superAGILE burst 070724B
  20. GRB 070809: Keck Imaging
  21. GRB 070810: Swift-XRT Team Refined Analysis
  22. GRB 070809: Swift-XRT refined analysis
  23. GRB 070810: Swift/UVOT Optical Counterpart
  24. GRB 070809, Swift-BAT refined analysis
  25. GRB 070809: Optical Pre-imaging from Palomar
  26. GRB 070808: Swift/UVOT upper limits
  27. GRB 070809: ROTSE-III Optical Limits
  28. GRB 070808 : Faulkes Telescope South Observations
  29. GCN Swift XRT update position notices and enhanced position circulars
  30. GRB 070808: Swift XRT refined analysis
  31. GRB 070808, Swift-BAT refined analysis
  32. GRB 070808: OPTIMA-Burst optical upper limit
  33. GRB 070808: Xinglong TNT optical Upper Limit
  34. GRB070808: Optical observations with KANATA
  35. GRB 070808: ROTSE-III Optical Limits
  36. GRB061121A: PROMPT Observations
  37. GRB070805 XRT and UVOT afterglow candidate
  38. GRB070612A: Radio upper limit from GMRT
  39. GRB 070721B: correct afterglow position
  40. Swift/UVOT observations of GRB070805
  41. GRB 070805, Swift-BAT refined analysis
  42. GRB 070805: Swift XRT initial analysis.
  43. UVOT observations of SAXJ1810.8-2609
  44. VLA non-detection of GRB 070721B
  45. GRB 070802: REM optical observations
  46. GRB 070724B: Swift-XRT afterglow confirmation
  47. GRB 070802: Swift-XRT refined analysis
  48. GRB070802: Swift/UVOT upper limits
  49. GRB 070802: Confirmation of the optical afterglow
  50. GRB 070802, Swift-BAT refined analysis
  51. GRB 070802: VLT redshift
  52. GRB 070802: refined Swift XRT position
  53. GRB 070802: V-band detection of the candidate afterglow
  54. GRB 070802: LCO I-band candidate
  55. GRB 070802: GROND J band candidate
  56. GRB 070802: LCO optical observations
  57. GRB 070802: Swift detection of a burst
  58. Konus-A observation of GRB 070729
  59. Swift/UVOT detection of GRB070714B
  60. AGILE-ACS position for the SGR 1806-20 July 27 burst
  61. GRB 070729: LCO optical imaging
  62. VLA upper limit on short hard burst GRB 070714B
  63. Intense burst from SGR 1806-20 detected on July 27
  64. GRB070729: Swift/UVOT upper limits
  65. GRB 070729: Swift-XRT refined analysis
  66. GRB 070729, Swift-BAT refined analysis
  67. GRB 070729: Magellan NIR Observations
  68. GRB 070724B: P60 Observations
  69. GRB 070724B: Swift/UVOT Upper limits
  70. GRB070721A: Swift/UVOT Detection of a Weak Afterglow
  71. GRB 070724B: Swift-XRT afterglow likely candidate
  72. GRB 070721A: optical observations
  73. GRB 070724A: further VLT observations
  74. GRB 070724B: Suzaku WAM observation of the prompt emission
  75. Konus-Wind observation of GRB 070724B
  76. GRB 070724B: Analysis of AGILE gamma-ray data
  77. GRB 070724B: Swift-XRT afterglow candidates
  78. Four radio sources in Swift-XRT error box of GRB 070724
  79. GRB 070724: optical observations
  80. GRB070724: Host galaxy redshift
  81. GRB 070724: P60 and Gemini Observations
  82. GRB 060814 - Keck host detection and redshift
  83. GRB 070724: Closer association with DSS source
  84. Swift/UVOT refined analysis of GRB070724
  85. GRB 070724: Swift-XRT Team refined analysis
  86. GRB 070724: Pre-Imaging Shows a Source in the XRT Error Circle
  87. Short-Hard GRB070714B: PROMPT Observations
  88. GRB 070724, Swift-BAT refined analysis of a short burst
  89. GRB 070721B: further observations and analysis
  90. GRB 070714B: Keck observations
  91. GRB 070721B: optical observations and proposed redshift
  92. Swift/UVOT observations of GRB070721B optical afterglow.
  93. GRB 070721B, Further Swift-BAT refined analysis
  94. Swift/UVOT Observations of GRB070721A
  95. GRB 070721B : Faulkes Telescope South observations
  96. GRB 070721B: Swift-XRT refined analysis
  97. GRB 070721A : Faulkes Telescope South optical limit
  98. GRB 070721A: Swift/XRT refined analysis
  99. GRB 070721B, Swift-BAT refined analysis
  100. GRB 070721A, Swift-BAT refined analysis

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