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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"

12407 results found.

  1. X-ray transient EP240315a: Montarrenti Observatory optical upper limit
  2. Fermi GRB 240317B: Global MASTER-Net observations report
  3. Fermi GRB 240317A: Global MASTER-Net observations report
  4. X-ray transient EP240315a: Kinder follow-up observations for AT 2024eju with Lulin observatory
  5. X-ray transient EP240315a: Nanshan/HMT optical upper limit
  6. Fermi trigger No 732299243: Global MASTER-Net observations report
  7. AT2024eju: followup observations with Liverpool Telescope suggest a fading transient
  8. Fermi GRB 240314A: Global MASTER-Net observations report
  9. GRB240204A: VIRT optical upper limit
  10. Fermi trigger No 731839490: Global MASTER-Net observations report
  11. Fermi-LAT gamma-ray observations of IceCube-240307A
  12. Fermi GRB 240310A: Global MASTER-Net observations report
  13. Swift GRB240309.61: Global MASTER-Net observations report
  14. GRB 240309A: MAXI/GSC detection
  15. IceCube-240307A: Upper limits from a search for additional neutrino events in IceCube
  16. Fermi trigger No 731571927: Global MASTER-Net observations report
  17. IceCube Alert 240307.32: Global MASTER-Net observations report
  18. Konus-Wind detection of GRB 231118A
  19. Fermi GRB 240306A: Global MASTER-Net observations report
  20. Fermi GRB 240305A: Global MASTER-Net observations report
  21. Fermi-LAT gamma-ray observations of IceCube-240229A
  22. Swift GRB240305.18: Global MASTER-Net observations report
  23. Swift GRB240305.16: Global MASTER-Net observations report
  24. Fermi GRB 240305C: Global MASTER-Net observations report
  25. Fermi trigger No 731303574: Global MASTER-Net observations report
  26. Transient EPW20240219aa: Optical observations with LDT
  27. Fermi trigger No 731161136: Global MASTER-Net observations report
  28. Swift GRB 240303A: Global MASTER-Net observations report
  29. IceCube-240229A: Upper limits from a search for additional neutrino events in IceCube
  30. GRB 240229A: DDOTI Upper Limits on the Afterglow
  31. GRB 240218A: NOEMA upper limit
  32. Fermi GRB 240229A: Global MASTER-Net observations report
  33. IceCube Alert 240229.66: Global MASTER-Net observations report
  34. GRB 240225B : MITSuME Akeno optical afterglow candidate detection
  35. GRB 240225B: WINTER near-IR observations and upper limits
  36. Fermi GRB 240227A: Global MASTER-Net observations report
  37. GRB 240218A: CMO SAI NIR upper limit
  38. Fermi GRB 240226A: Global MASTER-Net observations report
  39. GRB 240225B: Swift-XRT observations
  40. Transient EPW20240219aa: J-band upper limits from WINTER
  41. Transient EPW20240219aa: REM optical/NIR upper limits
  42. GRB 240222A: ATCA radio observations
  43. Fermi trigger No 730618809: Global MASTER-Net observations report
  44. GRB 240225B: MAXI/GSC detection
  45. Transient EPW20240219aa: Xinglong-2.16m optical upper limit
  46. Transient EPW20240219aa: GECKO: LOAO Optical Upper Limits
  47. Transient EPW20240219aa: 7DT Optical Upper Limits
  48. Transient EPW20240219aa: upper limit in gamma-ray range from SPI-ACS/INTEGRAL observations
  49. GRB 240222A: Swift/UVOT Upper Limits
  50. Swift GRB 240222A: Global MASTER-Net observations report
  51. Fermi GRB 240222A: Global MASTER-Net observations report
  52. GRB 240222A: REM optical and NIR early-time observations
  53. GRB 240222A: Swift detection of a burst
  54. Swift GRB240221.92: Global MASTER-Net observations report
  55. GRB 240218A: MeerLICHT upper limits
  56. Fermi GRB 240220A: Global MASTER-Net observations report
  57. Fermi trigger No 729914426: Global MASTER-Net observations report
  58. GRB 240218A : r-band upper limit from Observatoire de Haute-Provence
  59. GRB240218A: VLT/X-shooter upper limits
  60. GRB 240218A: Swift detection of a burst
  61. Swift GRB240218.08: Global MASTER-Net observations report
  62. Fermi GRB 240216A: Global MASTER-Net observations report
  63. Fermi trigger No 729719508: Global MASTER-Net observations report
  64. Fermi trigger No 729703985: Global MASTER-Net observations report
  65. Fermi trigger No 729650855: Global MASTER-Net observations report
  66. GRB 240128A: Further Swift-XRT observations
  67. GRB 240214A/1H 0451-560: MAXI/GSC detection
  68. Fermi GRB 240213A: Global MASTER-Net observations report
  69. Konus-Wind detection of GRB 240204A
  70. Fermi trigger No 729152364: Global MASTER-Net observations report
  71. Fermi-LAT gamma-ray observations of IceCube-240204A
  72. GRB240204A: Swift/UVOT Upper Limits
  73. Fermi trigger No 729012023: Global MASTER-Net observations report
  74. Konus-Wind detection of GRB 240205B (long / very soft)
  75. Fermi trigger No 728749569: Global MASTER-Net observations report
  76. GRB 240205B: MASTER OT J232550.14-550704.6 counterpart detection
  77. Swift GRB240205.93: Global MASTER-Net observations report
  78. GRB 240204A: Osservatorio Astronomico Nastro Verde upper limit
  79. IceCube-240204A: Upper limits from a search for additional neutrino events in IceCube
  80. Fermi trigger No 728796365: Global MASTER-Net observations report
  81. Fermi GRB 240204A: Global MASTER-Net observations report
  82. Fermi trigger No 728706420: Global MASTER-Net observations report
  83. IceCube Alert 240204.38: Global MASTER-Net observations report
  84. Konus-Wind detection of GRB 240124B
  85. Konus-Wind detection of GRB 240123C
  86. GRB 240128A: Swift-XRT observations
  87. GRB 240128A: MAXI/GSC detection
  88. Fermi GRB 240127A: Global MASTER-Net observations report
  89. GRB 240122A: ATCA detection of radio counterpart
  90. IceCube-240123A: Upper limits from a search for additional neutrino events in IceCube
  91. Fermi-LAT gamma-ray observations of IceCube-240123A
  92. IceCube Alert 240123.48: Global MASTER-Net observations report
  93. Fermi GRB 240123B: Global MASTER-Net observations report
  94. GRB 240122A: Swift/UVOT Upper Limits
  95. GRB 240122A: BOOTES-2/TELMA optical upper limit and 1.5m OSN detection
  96. GRB 240118A: Swift/UVOT Upper Limits
  97. Konus-Wind detection of GRB 240112A
  98. Swift GRB240123.46: Global MASTER-Net observations report
  99. GRB 240122A: Swift-XRT afterglow detection
  100. GRB 240122A: MAXI/GSC detection

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