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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"

21126 results found.

  1. IceCube-200916A: Upper limits from Fermi-GBM Observations
  2. Fermi-LAT Gamma-ray Observations of IceCube-200916A
  3. IceCube Alert 200916.86: Global MASTER-Net observations report
  4. Swift-XRT observations of IceCube 200911A
  5. Fermi GRB 200916A: Global MASTER-Net observations report
  6. Fermi trigger No 621893860: Global MASTER-Net observations report
  7. Fermi trigger No 621833240: Global MASTER-Net observations report
  8. Integral GRB200914.53: Global MASTER-Net observations report
  9. Fermi GRB 200914A: Global MASTER-Net observations report
  10. GRB 200914A: Swift-XRT observations
  11. IceCube Alert 200914.00: Global MASTER-Net observations report
  12. Fermi-LAT Gamma-ray Observations of IceCube-200911A and detection of a new gamma-ray source, Fermi J0330.1+3743
  13. GRB 200914A: Swift ToO observations
  14. IceCube Alert 200911.60: Global MASTER-Net observations report
  15. GRB 200826A: uGMRT radio upper limit at 1.25 GHz
  16. Swift GRB200909.97: Global MASTER-Net observations report
  17. GRB 200829A: T100 observations
  18. Fermi GRB 200909A: Global MASTER-Net observations report
  19. GRB 200907B: Swift/UVOT Upper Limits
  20. Fermi GRB 200908A: Global MASTER-Net observations report
  21. Swift GRB 200907B: Global MASTER-Net observations report
  22. Fermi GRB 200907C: Global MASTER-Net observations report
  23. Fermi GRB 200906A: Global MASTER-Net observations report
  24. GRB 200906A: LBT near-infrared upper limit
  25. GRB 200906A: Swift/UVOT Upper Limits
  26. Baksan Neutrino Observatory Alert 200905.99: Global MASTER-Net observations report
  27. Fermi GRB 200904A: Global MASTER-Net observations report
  28. Fermi GRB 200903C: Global MASTER-Net observations report
  29. GRB 200829A: optical observations, a light curve in R-filter
  30. Fermi GRB 200903B: Global MASTER-Net observations report
  31. Swift GRB200903.03: Global MASTER-Net observations report
  32. GRB 200901B: Swift/UVOT Detection
  33. GRB 200901A: Swift/UVOT Detection
  34. GRB 200829A: Swift/UVOT-XRT photometric redshift
  35. GRB 200901A: Swift-XRT observations
  36. Swift GRB200901.16: Global MASTER-Net observations report
  37. GRB 200829A: Koshka Zeiss-1000 optical observations
  38. GRB 200829A: Liverpool Telescope observations
  39. GRB 200829A: Continued Nanshan/NEXT optical observations
  40. GRB 200829A: further SAO RAS optical observations
  41. Fermi GRB 200830A: Global MASTER-Net observations report
  42. GRB 200829A: Nanshan/NEXT optical observations
  43. GRB 200829A: SAO RAS optical observations
  44. GRB 200826A
  45. GRB 200829A: THO optical observatios
  46. GRB 200829A: Global MASTER-Net OT detection
  47. GRB 200826A: Lowell Discovery Telescope observations of ZTF20abwysqy
  48. GRB 200829A: Swift/UVOT Detection
  49. Fermi trigger No 620402299: Global MASTER-Net observations report
  50. Swift GRB 200829A: Global MASTER-Net observations report
  51. GRB 200829A: TSHAO optical observations
  52. GRB 200826A: Kitab optical observations
  53. GRB 200826A: VLA Detection at 6 GHz
  54. GRB 200826A: Swift-XRT afterglow detection
  55. Fermi GRB 200826B: Global MASTER-Net observations report
  56. Fermi GRB 200824A: Global MASTER-Net observations report
  57. GRB200826A: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi Short GRB (Trigger 620108997)
  58. GRB200826A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 620108997)
  59. GRB 200826A: Tiled Swift observations
  60. Fermi GRB 200826A: Global MASTER-Net observations report
  61. GRB 200819A: Swift/UVOT Upper Limits
  62. Swift GRB200821.55: Global MASTER-Net observations report
  63. GRB 200815A: MASTER optical observations
  64. GRB 200819A: Optical Observations from HCT
  65. GRB 200729A: Lowell Discovery Telescope observations
  66. Baksan Neutrino Observatory Alert 200819.88: Global MASTER-Net observations report
  67. GRB 200819A / Swift J0125.7+6303: Ondrejov Perek-2m optical limit
  68. Swift GRB 200819A: Global MASTER-Net observations report
  69. GRB 200819A: Swift detection of a burst
  70. Baksan Neutrino Observatory Alert 200819.09: Global MASTER-Net observations report
  71. Fermi trigger No 619487843: Global MASTER-Net observations report
  72. Fermi GRB 200817A: Global MASTER-Net observations report
  73. Swift GRB200816.17: Global MASTER-Net observations report
  74. Fermi trigger No 619270776: Global MASTER-Net observations report
  75. HAWC alert 200815.26: MASTER optical observations
  76. Alert from the HAWC Burst Monitor HAWC-200814A
  77. Fermi GRB 200809B: Global MASTER-Net observations report
  78. GRB 200809B: BOOTES-3/YA optical upper limit
  79. GRB 200809B: Swift-XRT afterglow detection
  80. GRB 200809B: Swift ToO observations
  81. GRB 200809B: Swift/BAT-GUANO detection and arcminute localization
  82. Fermi trigger No 618642276: Global MASTER-Net observations report
  83. Fermi GRB 200808A: Global MASTER-Net observations report
  84. GRB 200806A: VIRT optical observations
  85. GRB 200806A: Swift/UVOT Possible Detection
  86. Fermi-LAT Gamma-ray Observations of IceCube-200806A
  87. IceCube-200806A: Upper limits from Fermi-GBM Observations
  88. Swift GRB 200806A: Global MASTER-Net observations report
  89. IceCube Alert 200806.58: Global MASTER-Net observations report
  90. GRB 200803B: MASTER possibly OT discovery
  91. GRB 200803A: Swift-XRT afterglow detection
  92. Fermi GRB 200803B: Global MASTER-Net observations report
  93. GRB 200803A: MASTER optical counterpart discovery
  94. GRB 200803A: Tiled Swift observations
  95. LAT GRB200803.15: Global MASTER-Net observations report
  96. Fermi GRB 200803A: Global MASTER-Net observations report
  97. Fermi GRB 200801B: Global MASTER-Net observations report
  98. Fermi GRB 200802A: Global MASTER-Net observations report
  99. Fermi GRB 200801A: Global MASTER-Net observations report
  100. Swift Detection of an SGR-like flare from AX J1846.4-0258

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