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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"

35341 results found.

  1. GRB 070810b: Image Subtraction of Multiple Keck Observations
  2. Las Campanas observations of possible TAROT GRB transient near IC
  3. Orphan GRB candidate in IC 4779 at TAROT La Silla observatory
  4. Konus-Wind observation of GRB 070824
  5. GRB 070824 - Combined SuperAGILE/IPN Localization
  6. Konus-Wind observation of very bright GRB 070821
  7. GRB 070731: Swift/UVOT Upper Limit
  8. IPN Localization of GRB 070821 (long, very bright)
  9. GRB 070805: UVOT afterglow candidate retraction
  10. GRB070810b: optical candidate
  11. GRB 070810A: ROTSE-III Refined Analysis
  12. GRB 061110A: redshift confirmed
  13. GRB 070810B : Faulkes Telescope South Observations
  14. GRB 070810A: Continued Keck Imaging
  15. GRB 070810B: Keck spectroscopy of possible host galaxies
  16. GRB070810B: Swift/UVOT Upper Limits
  17. GRB 070810B: XRT refined analysis
  18. GRB 070810B, Swift-BAT refined analysis
  19. GRB 070810: MASTER optical observation
  20. GRB 070809: Swift/UVOT Corrected Photometry
  21. Swift Alert 070810.8: MASTER optical observation
  22. Swift Trigger 287421: False trigger due to star tracker loss
  23. GRB 070810A: Swift-BAT refined analysis
  24. GRB 070810B: Xinglong TNT optical Upper Limit
  25. GRB070810B: Optical observations with KANATA
  26. GRB 070809: Swift/UVOT Upper Limits
  27. GRB 070810B: Swift detection of a short burst
  28. VLA upper limit on the short hard burst GRB 070729
  29. GRB 070810: Keck redshift and photometry
  30. No radio detection in superAGILE burst 070724B
  31. GRB 070809: Keck Imaging
  32. GRB 070810: Swift-XRT Team Refined Analysis
  33. GRB 070809: Swift-XRT refined analysis
  34. GRB 070810: enhanced Swift-XRT position
  35. GRB 070810: Swift/UVOT Optical Counterpart
  36. GRB 070810: ROTSE-III Detection of Optical Counterpart
  37. GRB 070810: Swift detection of a burst
  38. GRB 070809, Swift-BAT refined analysis
  39. GRB 070809: Optical Pre-imaging from Palomar
  40. GRB 070808: Swift/UVOT upper limits
  41. GRB 070809: ROTSE-III Optical Limits
  42. GRB 070809: Swift detection of a short burst
  43. GRB 070808 : Faulkes Telescope South Observations
  44. GRB 070808: Swift XRT refined analysis
  45. GRB 070808, Swift-BAT refined analysis
  46. GRB 070808: OPTIMA-Burst optical upper limit
  47. GRB 070808: Xinglong TNT optical Upper Limit
  48. GRB070808: Optical observations with KANATA
  49. GRB070808 - SDSS Pre-Burst Observations
  50. GRB 070808: ROTSE-III Optical Limits
  51. GRB 070808: Swift detection of a burst
  52. GRB061121A: PROMPT Observations
  53. GRB070805 XRT and UVOT afterglow candidate
  54. Swift trigger on 4U 1700-377 while star tracker loss-of-lock
  55. GRB070612A: Radio upper limit from GMRT
  56. GRB 070721B: correct afterglow position
  57. GRB 070805, Swift-BAT refined analysis
  58. GRB 070805: Swift XRT initial analysis.
  59. GRB 070805: Swift/UVOT initial analysis
  60. GRB 070805: Swift detection of a burst
  61. VLA non-detection of GRB 070721B
  62. GRB 070802: REM optical observations
  63. GRB 070724B: Swift-XRT afterglow confirmation
  64. GRB 070802: Swift-XRT refined analysis
  65. GRB 070802: Confirmation of the optical afterglow
  66. GRB 070802, Swift-BAT refined analysis
  67. GRB 070802: VLT redshift
  68. GRB 070802: refined Swift XRT position
  69. GRB 070802: V-band detection of the candidate afterglow
  70. GRB 070802: LCO I-band candidate
  71. GRB 070802: GROND J band candidate
  72. GRB 070802: LCO optical observations
  73. GRB 070802: Swift detection of a burst
  74. GRB 070731, Swift-BAT refined analysis
  75. Konus-A observation of GRB 070729
  76. Swift/UVOT detection of GRB070714B
  77. GRB 070724B: pseudo-z ~ 1.10 from prompt emission spectrum
  78. GRB 070729: LCO optical imaging
  79. VLA upper limit on short hard burst GRB 070714B
  80. Intense burst from SGR 1806-20 detected on July 27
  81. GRB 070729: Swift-XRT refined analysis
  82. GRB 070729, Swift-BAT refined analysis
  83. GRB 070729: Magellan NIR Observations
  84. GRB 070724B: P60 Observations
  85. GRB 070729: Swift detection of a short hard burst
  86. GRB 070724B: Swift/UVOT Upper limits
  87. GRB 070724B: Swift-XRT afterglow likely candidate
  88. GRB 070721A: optical observations
  89. GRB 070724A: further VLT observations
  90. GRB 070724B: Suzaku WAM observation of the prompt emission
  91. Konus-Wind observation of GRB 070724B
  92. GRB 070724B: Analysis of AGILE gamma-ray data
  93. GRB 070724B: Swift-XRT afterglow candidates
  94. GRB 070724b: First Gamma Ray Burst Localization by SuperAGILE onboard
  95. Four radio sources in Swift-XRT error box of GRB 070724
  96. GRB 070724: optical observations
  97. GRB 070724: P60 and Gemini Observations
  98. GRB 060814 - Keck host detection and redshift
  99. GRB 070724: IR observations
  100. GRB 070724: Closer association with DSS source

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