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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').
Advanced Search

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"

12403 results found.

  1. LIGO/Virgo G275404: REM optical/NIR observations
  2. LIGO/Virgo G275404: Fermi-LAT search for a high-energy gamma-ray counterpart
  3. LIGO/Virgo G275404: INTEGRAL search for a prompt gamma-ray counterpart
  4. LIGO/Virgo G275404 ANTARES search
  5. LIGO/Virgo G275404: Swift/BAT data search
  6. LIGO/Virgo G274296: Swift/BAT data search
  7. LIGO/Virgo G275404: AGILE-GRID preliminary analysis
  8. LIGO/Virgo G275404: Fermi GBM Observations
  9. LIGO/Virgo G275404: MASTER automatic follow up observations
  10. Konus-Wind observation of GRB 170222A
  11. LIGO/Virgo G274296: Asiago 1.82m Optical Observations
  12. LIGO/Virgo G274296: AstroSat CZTI upper limits
  13. LIGO/Virgo G274296 ANTARES search
  14. LIGO/Virgo G274296: INTEGRAL search for a prompt gamma-ray counterpart
  15. LIGO/VIRGO G274296: Fermi GBM Observations
  16. LIGO/VIRGO G274296: AGILE-GRID preliminary analysis
  17. Trigger 738728: Swift triggered on noise near NGC 4096
  18. GRB 170214A: Mondy optical upper limit
  19. GRB 170214A: Swift/UVOT Upper Limits
  20. GRB 170214A: Swift-XRT observations
  21. GRB 170208B: IRSF upper limits
  22. GRB 170208A: IRSF upper limits
  23. GRB 170203A: 15 GHz upper limits from AMI
  24. GRB 170202A: 15 GHz upper limits from AMI
  25. GRB 170209A: Swift-XRT observations
  26. Konus-Wind observation of GRB 170209A
  27. GRB 170208B: Swift/UVOT Upper Limits
  28. GRB 170208B: RATIR Optical and NIR Observations
  29. Fermi Trigger 508295323: MASTER-OAFA possible OT detection
  30. LIGO/Virgo G270580: AstroSat CZTI upper limits
  31. GRB 170208A: Swift/UVOT Upper Limits
  32. Konus-Wind observation of GRB 170208B
  33. Konus-Wind observation of GRB 170208A
  34. GRB 170208B: GROND observations
  35. GRB 170208B: NOT upper limits
  36. GRB 170208B: Etelman observatory optical observations
  37. GRB 170208B: Swift detection of a burst
  38. GRB 170206B: Swift/UVOT Upper Limits
  39. LIGO/Virgo G270580: ANTARES upper limits
  40. GRB 170205A: Swift/UVOT Detection of a Fading Afterglow
  41. Konus-Wind observation of GRB 170205A
  42. GRB 170202A: Swift/UVOT Detection
  43. GRB 170202A: Kanata optical and infrared observations
  44. GRB 170202A: Mini-MegaTORTORA upper limits
  45. GRB 170131A: Swift/UVOT Upper Limits
  46. GRB 170131A: Swift-XRT observations
  47. GRB 170127C: Swift-XRT observations
  48. GRB 170127A: GROND Upper limits
  49. GRB 170127B: Swift/UVOT Upper Limits
  50. GRB 170127A: Swift/UVOT Upper Limits
  51. GRB 170127B: NOT r-band upper limits
  52. Konus-Wind observation of GRB 170126A
  53. GRB 170127B: MASTER-Kislovodsk early optical observations
  54. GRB 170127A: Swift detection of a burst
  55. GRB 170126A: Swift/UVOT Detection of a Fading Afterglow
  56. LIGO/Virgo G270580: Fermi GBM Observations
  57. GRB 170115A: 15 GHz upper limits from AMI
  58. LIGO/Virgo G270580: MAXI/GSC observations
  59. LIGO/Virgo G270580: Swift-XRT follow-up of PS17yt
  60. LIGO/Virgo G268556: ANTARES upper limits
  61. GRB 170121B: Swift-XRT and UVOT observations
  62. LIGO/Virgo G268556/GW170104: MAXI/GSC observations
  63. LIGO/Virgo G270580: INTEGRAL search of temporally coincident prompt hard X-ray
  64. LIGO/Virgo G270580: Swift-XRT sources
  65. LIGO/Virgo G270580: Swift/BAT data search
  66. LIGO/Virgo G270580: AGILE MCAL and Super-AGILE Observations
  67. LIGO/Virgo G270580 ANTARES search
  68. GRB 170117A: Swift/UVOT Upper Limits
  69. GRB 170117A: Swift-XRT observations
  70. GRB 170115A : AbAO optical upper limit
  71. GRB 170115A: Swift/UVOT Upper Limits
  72. GRB 170115B: Swift-XRT observations
  73. LIGO/Virgo G268556: Swift-XRT observations of iPTF17cw
  74. GRB 170115A: Swift detection of a burst
  75. GRB 170113A: GROND afterglow observations
  76. GRB 170113A: Swift/UVOT Observations
  77. GRB 161214B: 15 GHz upper limits from AMI
  78. GRB 170112A: Swift/UVOT Upper Limits
  79. GRB 170101A: 15 GHz upper limits from AMI
  80. GRB 161217A: 15 GHz upper limits from AMI
  81. GRB 170111A: Swift/UVOT Upper Limits
  82. GRB 170112A: Swift-XRT observations
  83. GRB 170112A: MASTER-OAFA (Argentina) early optical observations
  84. GRB 170112A: Swift detection of a short burst
  85. LIGO/Virgo G268556: Early SWASP limits of ATLAS17aeu
  86. LIGO/Virgo G268556: Additional GROWTH follow up observation of iPTF Optical Transient Candidates
  87. GRB 170111A: MASTER-OAFA (Argentina) prompt OT observations
  88. GRB 170111A: Swift detection of a burst
  89. LIGO/Virgo G268556: Swift/BAT data search
  90. LIGO/Virgo G268556: Lijiang Observatory GMG Telescope Upper Limit on ATLAS17aeu
  91. LIGO/Virgo G268556: NOWT of EWE, Xinglong 0.6/0.9m, Xuyi 1m optical upper limits of ATLAS17aeu and a reminder of GCN 20394
  92. LIGO/Virgo G268556/GW170104: Lomonosov BDRG observations
  93. LIGO/Virgo G268556: Swift/UVOT observations of ATLAS17aeu
  94. LIGO/Virgo G268556: AGILE-GRID preliminary analysis
  95. Swift Trigger 730874 is not astrophysical
  96. LIGO/Virgo G268556: Swift-XRT detection of ATLAS17aeu
  97. LIGO/Virgo G268556/GW170104: Asiago Observations
  98. Swift Trigger 730513 is not an astrophysical event
  99. LIGO/Virgo G268556: AGILE MCAL and Super-AGILE Observations
  100. LIGO/Virgo G268556: Swift-XRT sources

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