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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"

43169 results found.

  1. GRB 131014A: XRT position information
  2. GRB131018A, optical observations
  3. GRB 131018A: Swift detection of a burst
  4. GRB 131014A: Suzaku WAM observation of the prompt emission
  5. GRB 131014A: GROND observations
  6. GRB 131014A: RATIR Optical/NIR Afterglow Confirmation
  7. Fermi GBM data availability during U.S. government shutdown
  8. GRB 131011A: Swift/UVOT Upper Limits
  9. GRB 131014A: Swift/UVOT Upper Limits
  10. GRB 131014A: RATIR Optical and NIR Observations
  11. GRB 131014A: Enhanced XRT position
  12. Konus-Wind observation of GRB 131014A
  13. GRB 131014A: NOT afterglow candidate
  14. GRB 131014A: Nanshan optical observations
  15. GRB 131014A: Swift detection of a possible X-ray afterglow
  16. GRB 131014A Tiled Swift observations
  17. GRB 131014A: Fermi-LAT detection
  18. GRB 131014A: Fermi GBM detection
  19. GRB 131011A: Fermi GBM detection
  20. iPTF 13dsw/Fermi403206457: X-Shooter redshift
  21. Swift-XRT detection of iPTF 13dsw/Fermi403206457
  22. GRB 131011A: GROND afterglow observations
  23. Fermi403206457: continued P60 observations and fading behavior
  24. Fermi403206457: NOT optical observations
  25. Fermi403206457: iPTF detection of a possible optical afterglow
  26. Trigger 574266 is not a Swift detection of a known source
  27. GRB 130925A: Possible signatures of binary nature in the afterglow - Request for observations
  28. GRB 130831A: Continued RATIR Optical and NIR Observations
  29. GRB 130831A: VLT/FORS2 spectroscopic detection of a supernova
  30. GRB 131004A: MOSFIRE NIR imaging
  31. GRB 131004A: Correction to XRT refined analysis
  32. GRB 131004A: Skynet PROMPT/DSO-14 upper limits
  33. GRB 131004A, Swift-BAT refined analysis
  34. GRB 131004A: Fermi GBM observation
  35. GRB 131004A: CARMA 93 GHz upper limit
  36. GRB 131004A: Swift/UVOT Detection
  37. GRB 131004A: RATIR Optical and NIR Upper Limits
  38. GRB 131004A: Swift-XRT refined Analysis
  39. GRB131004A: TNG Redshift confirmation
  40. GRB 131004A: GROND observations of the afterglow
  41. GRB 131004A: Enhanced Swift-XRT position
  42. GRB131004A: Magellan Redshift
  43. GRB 131004A: Liverpool Telescope optical afterglow observations
  44. GRB 131004A: optical afterglow from the NOT
  45. GRB 131004A: Swift detection of a burst (may be short)
  46. GRB 131002A, Swift-BAT refined analysis
  47. GRB 130925A: 3mm observations with CARMA
  48. GRB 131002A: Fermi GBM observation
  49. GRB 130925A/Sw J0244-2609: mm observations at PdBI
  50. GRB 131002B, Swift-BAT refined analysis
  51. GRB 131002B: GROND upper limits
  52. GRB 131002B: Swift-XRT Refined Analysis
  53. GRB 131002B: Swift/UVOT Upper Limits
  54. GRB 131002A: Swift/UVOT Detection
  55. GRB 131001A, Swift-BAT refined analysis
  56. GRB 131002A: Swift-XRT refined Analysis
  57. GRB 131002B: Enhanced Swift-XRT position
  58. Swift J1242.9-3530, Swift-BAT refined analysis
  59. GRB 131001A: Swift UVOT and XRT Upper Limits
  60. GRB 131002A: Enhanced Swift-XRT position
  61. NuSTAR observations of GRB 130925A
  62. GRB 131002B: Swift detection of a burst
  63. GRB 131002A: Swift detection of a burst
  64. GRB 131001A detected in ground analysis of Swift-BAT data
  65. GRB 130925A: continuing Swift/XRT monitoring
  66. Swift Operations in the event of a US Government shutdown
  67. IPN Observations of GRB 130925A
  68. US Government shutdown may impact GRB operation of GCN
  69. GRB 130930A: Swift detection of a burst
  70. GRB 130929A: Swift/UVOT Upper Limits
  71. GRB 130831A: Continued RATIR Optical and NIR Observations
  72. GRB 130929A: Swift-XRT refined Analysis
  73. GRB 130929A: Enhanced Swift-XRT position
  74. GRB 130929A: TAROT La Silla observatory optical observations
  75. GRB 130929A: Swift detection of a burst
  76. Fermi LAT Upper Limits on GRB 130925A
  77. GRB 130925A: Swift/UVOT Detection of the Host Galaxy
  78. GRB 130925A: Swift/UVOT Upper Limits
  79. GRB 130925A: sub-mm non-detection with SMA
  80. GRB 130925A: Continued RATIR Optical and NIR Observations
  81. GRB 130925A: Fermi GBM Detection
  82. Konus-Wind observation of GRB 130925A
  83. Observation of possible GRB/TDE 130925A by INTEGRAL/SPI-ACS: three activity episodes
  84. GRB 130925A: RATIR Optical and NIR Observations
  85. GRB 130925A Swift-BAT refined analysis
  86. GRB 130925A: Historical non-detection from Rosat-HRI
  87. Fermi GBM detection of GRB 130925A and a possible precursor
  88. GRB 130925A: Swift-XRT refined Analysis
  89. GRB 130925A: Initial Similarities to Swift J1644+57
  90. GRB 130925A: TAROT La Silla observatory optical observations
  91. GRB 130925A: Enhanced Swift-XRT position
  92. GRB 130925A: VLT/X-shooter redshift
  93. GRB 130925A: VLT/UVES observations
  94. GRB 130925A: MAXI/GSC detection
  95. GRB 130925A: GROND afterglow candidate
  96. GRB 130925A: Swift detection of a burst
  97. IPN Triangulation of SGR-like burst 130913 - probable association with SGR/AXP 1E1841-045
  98. GRB 130702A: RTT150 optical observations
  99. GRB 130831A: RATIR Confirmation of NIR/Optical Afterglow Flattening
  100. GRB 130903A: optical observations

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