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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

21980 results found.

  1. GRB 070920B: TAROT La Silla observatory optical observations
  2. INTEGRAL ToO observations of SGR1806-20
  3. GRB 070917: Confirmation of the X-ray afterglow
  4. GRB 070920b: LCO optical observations
  5. GRB 070920B: NOT optical observations
  6. GRB 070920B: Swift detection of a burst
  7. GRB 070920: TAROT Calern observatory optical observations
  8. GRB 070920: Swift detection of a burst
  9. GRB070917: Confirmation of optical afterglow
  10. GRB920925C: search for host galaxy
  11. GRB070917: optical observations
  12. GRB 070917: P60 Observations
  13. Swift Status and XRT Calibration Uncertainties
  14. GRB 070917: Swift-XRT observations
  15. GRB 070917: R band observations
  16. GRB 070917: Swift detection of a bright burst
  17. GRB 070913: SMARTS optical/IR observations
  18. GRB 070913: TAROT La Silla observatory optical observations
  19. GRB 070913: Swift detection of a burst
  20. GRB 070911: PAIRITEL IR Observations
  21. GRB 070809: Confirmation of optical transient
  22. Observations of possible TAROT GRB transient near IC 4779
  23. Candidate Orphan GRB Optical Transient in IC 4779
  24. GRB 070810b: Image Subtraction of Multiple Keck Observations
  25. Las Campanas observations of possible TAROT GRB transient near IC
  26. Orphan GRB candidate in IC 4779 at TAROT La Silla observatory
  27. GRB 070731: Swift/UVOT Upper Limit
  28. GRB 070805: UVOT afterglow candidate retraction
  29. GRB070810b: optical candidate
  30. GRB 070810B : Faulkes Telescope South Observations
  31. GRB 070810A: Continued Keck Imaging
  32. GRB 070810B: Keck spectroscopy of possible host galaxies
  33. GRB070810B: Swift/UVOT Upper Limits
  34. GRB 070810B: XRT refined analysis
  35. GRB070810B: Optical observations with KANATA
  36. GRB 070809: Swift/UVOT Upper Limits
  37. GRB 070810B: Swift detection of a short burst
  38. GRB 070809: Keck Imaging
  39. GRB 070810: ROTSE-III Detection of Optical Counterpart
  40. GRB 070808: Swift/UVOT upper limits
  41. GRB 070808 : Faulkes Telescope South Observations
  42. GRB070808: Optical observations with KANATA
  43. GRB070808 - SDSS Pre-Burst Observations
  44. GRB061121A: PROMPT Observations
  45. GRB070805 XRT and UVOT afterglow candidate
  46. Swift/UVOT observations of GRB070805
  47. UVOT observations of SAXJ1810.8-2609
  48. GRB 070802: REM optical observations
  49. GRB 070724B: Swift-XRT afterglow confirmation
  50. GRB070802: Swift/UVOT upper limits
  51. GRB 070802: Confirmation of the optical afterglow
  52. GRB 070802: GROND J band candidate
  53. GRB 070802: LCO optical observations
  54. GRB 070729: LCO optical imaging
  55. GRB070729: Swift/UVOT upper limits
  56. GRB 070729: Magellan NIR Observations
  57. GRB 070724B: P60 Observations
  58. GRB 070724B: Swift/UVOT Upper limits
  59. GRB070721A: Swift/UVOT Detection of a Weak Afterglow
  60. GRB 070724B: Swift-XRT afterglow likely candidate
  61. GRB 070721A: optical observations
  62. GRB 070724A: further VLT observations
  63. Four radio sources in Swift-XRT error box of GRB 070724
  64. GRB 070724: optical observations
  65. GRB070724: Host galaxy redshift
  66. GRB 070724: P60 and Gemini Observations
  67. GRB 060814 - Keck host detection and redshift
  68. GRB 070724: IR observations
  69. GRB 070724: Closer association with DSS source
  70. GRB 070724: Pre-Imaging Shows a Source in the XRT Error Circle
  71. Short-Hard GRB070714B: PROMPT Observations
  72. GRB 070721B: further observations and analysis
  73. GRB 070714B: Keck observations
  74. GRB 070721B: optical observations and proposed redshift
  75. Swift/UVOT observations of GRB070721B optical afterglow.
  76. Swift/UVOT Observations of GRB070721A
  77. GRB 070721B : Faulkes Telescope South observations
  78. GRB070714B: TNG NIR observations
  79. GRB 070714A: Swift/UVOT Upper limits
  80. GRB 070714B: Swift/UVOT Upper Limits
  81. GRB 070714B: confirmation of optical afterglow
  82. GRB 070707: Swift-XRT follow-up observations
  83. SN 2007bg - off-axis GRB?
  84. GRB 070704: RTT150 optical observations
  85. GRB 070707: optical afterglow
  86. GRB 070707: object inside XRT error circle
  87. Swift/UVOT Observations of GRB070707
  88. GRB 070707: VLT observations
  89. GRB 070429B: NIR Observations
  90. GRB070704: FAVOR optical observations
  91. GRB 070704 : Liverpool Telescope Observations
  92. GRB 070611: VLT observations
  93. Swift/UVOT Observations of GRB070704
  94. GRB 070628 Swift-UVOT Refined Analysis
  95. GRB 070628: NIR detection of afterglow
  96. GRB 070628: TAROT La Silla observatory optical observations
  97. GRB 070628: Watcher Observations
  98. Swift UVOT Observations of GRB 070628
  99. GRB 070628: Swift detection of a possible burst
  100. GRB 070612A: Allen Telescope Array Observations

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