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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.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

27162 results found.

  1. Swift Trigger 650221 / IGR J00291+5934: MASTER-IAC OT observations
  2. Fermi GBM trigger 150725291 is not a GRB
  3. Trigger 650221: Swift detection of a IGR J00291+5934
  4. GRB 150724A: Swift-XRT refined Analysis
  5. Swift IGR J00291+5934: MASTER Optical flare detection
  6. GRB 150724A: Swift/UVOT Upper Limits
  7. IGR J00291+5934: Swift-BAT refined analysis
  8. GRB 150724A: Swift-BAT refined analysis
  9. SGR 1E 1841-045 (Swift trigger 649113): Terskol upper limit
  10. Trigger 650140: Swift detection of IGR J00291+5934
  11. GRB 150724A: Swift detection of a burst
  12. GRB 150722A: LCOGT-Sutherland observations
  13. GRB 150722A: Swift-BAT refined analysis
  14. GRB 150722A: Swift-XRT refined Analysis
  15. GRB 150722A: Swift/UVOT Upper Limits
  16. GRB 150720A: Swift/UVOT Upper Limits
  17. GRB 150722A: Swift-XRT observations
  18. GRB 150722A: Swift detection of a burst
  19. GRB 150721A: Fermi GBM detection
  20. GRB 150720A: Swift-XRT refined Analysis
  21. GRB 150720A: Swift-BAT refined analysis
  22. Swift Trigger 649706: a possible GRB or bright Galactic transient
  23. GRB 150716A: KAIT Optical Upper Limit
  24. GRB 150711A: Burakan-ISON optical observations
  25. GRB 150716A: Swift-BAT refined analysis
  26. GRB 150716A: Swift/UVOT Upper Limits
  27. GRB 150716A: Continued RATIR Optical Observations
  28. Swift trigger 649143 is not AX J1619.4-4945 or other astrophysical source
  29. GRB 150716A: Swift-XRT refined Analysis
  30. GRB 150716A: P60 Candidate Optical Afterglow
  31. GRB 150716A: RATIR Optical Observations
  32. GRB 150716A: Swift detection of a burst
  33. Fermi GBM triggers bn150715759 and bn150715817 are not due to GRBs
  34. Trigger 649143: Swift detection of AX J1619.4-4945
  35. Trigger 649113: Swift detection of SGR 1E 1841-045
  36. Fermi Gamma-ray Burst Monitor triggers that are not GRBs
  37. Fermi GBM trigger 458312518/150711543 is not a GRB
  38. GRB 150711A: Swift-BAT refined analysis
  39. GRB 150711A: Swift/UVOT Upper Limits
  40. GRB 150711A: Swift-XRT refined Analysis
  41. GRB 150711A: Fermi GBM detection
  42. GRB 150711A: Observations from the 2.5m NOT
  43. GRB 150711A: Swift detection of a burst
  44. GRB 150710A: Swift/UVOT Upper Limits
  45. MASTER OT Detection during Fermi Trigger 458235025 inspection
  46. Swift-XRT observations of GRB 150710A
  47. Confirmation that Swift trigger 648422 is not an astrophysical source
  48. Konus-Wind observation of GRB 150710A (Swift trigger 648437)
  49. GRB 150710A: Swift-BAT refined analysis
  50. GRB 150710A: RATIR Observations
  51. Swift trigger 648437: A GRB or a burst from 1RXS J125754.7+141850
  52. Swift Trigger 648422: Swift-XRT observations
  53. Trigger 648422: Swift possible detection of a source in NGC4552
  54. Fermi Gamma-ray Burst Monitor Trigger bn150705731 is not a GRB
  55. GRB 150702A: Fermi GBM detection
  56. IPN Triangulation of GRB 150702A
  57. GRB 150702A: MASTER-SAAO inspection
  58. GRB 150702A: Fermi-LAT detection
  59. Fermi GBM Observations is no longer triggerin on V404 Cyg
  60. Swift Trigger 647642 is probably not an astrophysical source
  61. Fermi Gamma-ray Burst Monitor Trigger 150626873 is not a GRB
  62. Fermi Gamma-ray Burst Monitor Trigger bn150628857 is not a GRB
  63. Fermi Gamma-ray Burst Monitor trigger bn150629779 is not a GRB
  64. GRB 150626B, Swift-BAT refined analysis
  65. V404 Cyg activity (Swift, Fermi, INTGRAL, KONUS, MAXI detection): optical observations in TSHAO, Khureltogot, and AAO
  66. GRB 150627A: corection to 17978
  67. GRB 150627A: MASTER-SAAO OT Detection
  68. GRB 150627A: Swift/UVOT Detection
  69. GRB 150627A: Fermi GBM observation
  70. GRB 150626B: Swift-XRT refined Analysis
  71. GRB 150626A: Swift-BAT refined analysis
  72. GRB 150627A: Fermi-LAT detection
  73. GRB 150626B: Swift/UVOT Upper Limits
  74. GRB 150626B: MASTER observations
  75. GRB 150626B: Swift detection of a burst
  76. GRB 150626A: Swift-XRT refined Analysis
  77. GRB 150626A: Swift/UVOT Upper Limits
  78. Trigger 646721: Swift detection of V 404 Cyg
  79. GRB 150626A: Swift detection of a burst
  80. Swift Trigger 646423 is GS 1354-645
  81. Trigger 645944: Swift detection of H1745-203
  82. Fermi Gamma-ray Burst Monitor triggers that are not GRBs
  83. V404 Cyg: MASTER Swift, Integral alert observations
  84. Fermi Gamma-ray Burst Monitor triggers bn150622899 and bn150623043 are not GRBs
  85. Swift Trigger 645340 was Sco X-1
  86. Swift Trigger 645340: a possible GRB
  87. Trigger 645176: Swift detection of V404 Cyg
  88. V404 Cyg: Fermi GBM observations
  89. GRB 150616A: Watcher optical upper limit
  90. Swift triggers again on V404 Cyg
  91. Swift Trigger 644596 is V404 Cyg
  92. Swift Trigger 644520 is V404 Cyg
  93. IBAS trigger 7015 is not a GRB
  94. GRB 150616A: Swift/UVOT Upper Limits
  95. GRB 150616A: Swift-BAT refined analysis
  96. V404 Cyg outburst (Swift trigger 643949 ): TSHAO optical observations
  97. GRB 150616A: Swift-XRT refined Analysis
  98. Konus-Wind observation of Galactic transient V404 Cyg in outburst
  99. GRB 150616A: Swift detection of a burst
  100. Fermi GBM trigger 150616734 is not a GRB

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