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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"

21129 results found.

  1. Swift-XRT observations of IceCube 200916A
  2. Swift GRB 200917A: Global MASTER-Net observations report
  3. IceCube-200916A: Two Candidate Counterparts from the Zwicky Transient Facility
  4. IceCube-200916A: Upper limits from Fermi-GBM Observations
  5. Fermi-LAT Gamma-ray Observations of IceCube-200916A
  6. IceCube Alert 200916.86: Global MASTER-Net observations report
  7. Swift-XRT observations of IceCube 200911A
  8. Fermi GRB 200916A: Global MASTER-Net observations report
  9. Fermi trigger No 621893860: Global MASTER-Net observations report
  10. Fermi trigger No 621833240: Global MASTER-Net observations report
  11. Integral GRB200914.53: Global MASTER-Net observations report
  12. Fermi GRB 200914A: Global MASTER-Net observations report
  13. GRB 200914A: Swift-XRT observations
  14. IceCube Alert 200914.00: Global MASTER-Net observations report
  15. Fermi-LAT Gamma-ray Observations of IceCube-200911A and detection of a new gamma-ray source, Fermi J0330.1+3743
  16. GRB 200914A: Swift ToO observations
  17. IceCube Alert 200911.60: Global MASTER-Net observations report
  18. GRB 200826A: uGMRT radio upper limit at 1.25 GHz
  19. Swift GRB200909.97: Global MASTER-Net observations report
  20. GRB 200829A: T100 observations
  21. Fermi GRB 200909A: Global MASTER-Net observations report
  22. GRB 200907B: Swift/UVOT Upper Limits
  23. Fermi GRB 200908A: Global MASTER-Net observations report
  24. Swift GRB 200907B: Global MASTER-Net observations report
  25. Fermi GRB 200907C: Global MASTER-Net observations report
  26. Fermi GRB 200906A: Global MASTER-Net observations report
  27. GRB 200906A: LBT near-infrared upper limit
  28. GRB 200906A: Swift/UVOT Upper Limits
  29. Baksan Neutrino Observatory Alert 200905.99: Global MASTER-Net observations report
  30. Fermi GRB 200904A: Global MASTER-Net observations report
  31. Fermi GRB 200903C: Global MASTER-Net observations report
  32. GRB 200829A: optical observations, a light curve in R-filter
  33. Fermi GRB 200903B: Global MASTER-Net observations report
  34. Swift GRB200903.03: Global MASTER-Net observations report
  35. GRB 200901B: Swift/UVOT Detection
  36. GRB 200901A: Swift/UVOT Detection
  37. GRB 200829A: Swift/UVOT-XRT photometric redshift
  38. GRB 200901A: Swift-XRT observations
  39. Swift GRB200901.16: Global MASTER-Net observations report
  40. GRB 200829A: Koshka Zeiss-1000 optical observations
  41. GRB 200829A: Liverpool Telescope observations
  42. GRB 200829A: Continued Nanshan/NEXT optical observations
  43. GRB 200829A: further SAO RAS optical observations
  44. Fermi GRB 200830A: Global MASTER-Net observations report
  45. GRB 200829A: Nanshan/NEXT optical observations
  46. GRB 200829A: SAO RAS optical observations
  47. GRB 200826A
  48. GRB 200829A: THO optical observatios
  49. GRB 200829A: Global MASTER-Net OT detection
  50. GRB 200826A: Lowell Discovery Telescope observations of ZTF20abwysqy
  51. GRB 200829A: Swift/UVOT Detection
  52. Fermi trigger No 620402299: Global MASTER-Net observations report
  53. Swift GRB 200829A: Global MASTER-Net observations report
  54. GRB 200829A: TSHAO optical observations
  55. GRB 200826A: Kitab optical observations
  56. GRB 200826A: VLA Detection at 6 GHz
  57. GRB 200826A: Swift-XRT afterglow detection
  58. Fermi GRB 200826B: Global MASTER-Net observations report
  59. Fermi GRB 200824A: Global MASTER-Net observations report
  60. GRB200826A: Zwicky Transient Facility Identifies Optical Afterglow Candidate of a Fermi Short GRB (Trigger 620108997)
  61. GRB200826A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 620108997)
  62. GRB 200826A: Tiled Swift observations
  63. Fermi GRB 200826A: Global MASTER-Net observations report
  64. GRB 200819A: Swift/UVOT Upper Limits
  65. Swift GRB200821.55: Global MASTER-Net observations report
  66. GRB 200815A: MASTER optical observations
  67. GRB 200819A: Optical Observations from HCT
  68. GRB 200729A: Lowell Discovery Telescope observations
  69. Baksan Neutrino Observatory Alert 200819.88: Global MASTER-Net observations report
  70. GRB 200819A / Swift J0125.7+6303: Ondrejov Perek-2m optical limit
  71. Swift GRB 200819A: Global MASTER-Net observations report
  72. GRB 200819A: Swift detection of a burst
  73. Baksan Neutrino Observatory Alert 200819.09: Global MASTER-Net observations report
  74. Fermi trigger No 619487843: Global MASTER-Net observations report
  75. Fermi GRB 200817A: Global MASTER-Net observations report
  76. Swift GRB200816.17: Global MASTER-Net observations report
  77. Fermi trigger No 619270776: Global MASTER-Net observations report
  78. HAWC alert 200815.26: MASTER optical observations
  79. Alert from the HAWC Burst Monitor HAWC-200814A
  80. Fermi GRB 200809B: Global MASTER-Net observations report
  81. GRB 200809B: BOOTES-3/YA optical upper limit
  82. GRB 200809B: Swift-XRT afterglow detection
  83. GRB 200809B: Swift ToO observations
  84. GRB 200809B: Swift/BAT-GUANO detection and arcminute localization
  85. Fermi trigger No 618642276: Global MASTER-Net observations report
  86. Fermi GRB 200808A: Global MASTER-Net observations report
  87. GRB 200806A: VIRT optical observations
  88. GRB 200806A: Swift/UVOT Possible Detection
  89. Fermi-LAT Gamma-ray Observations of IceCube-200806A
  90. IceCube-200806A: Upper limits from Fermi-GBM Observations
  91. Swift GRB 200806A: Global MASTER-Net observations report
  92. IceCube Alert 200806.58: Global MASTER-Net observations report
  93. GRB 200803B: MASTER possibly OT discovery
  94. GRB 200803A: Swift-XRT afterglow detection
  95. Fermi GRB 200803B: Global MASTER-Net observations report
  96. GRB 200803A: MASTER optical counterpart discovery
  97. GRB 200803A: Tiled Swift observations
  98. LAT GRB200803.15: Global MASTER-Net observations report
  99. Fermi GRB 200803A: Global MASTER-Net observations report
  100. Fermi GRB 200801B: Global MASTER-Net observations report

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