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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"

21112 results found.

  1. GRB 220611A: Continued Gemini Infrared Observations
  2. GRB 220617A: TNG optical observations
  3. Fermi trigger No 677307509: Global MASTER-Net observations report
  4. Fermi trigger No 677236224: Global MASTER-Net observations report
  5. GRB 220611A optical counterpart
  6. GRB 220618A: Swift/UVOT Upper Limits
  7. GRB220611A: Gemini Optical Afterglow Confirmation
  8. GRB 220617A: Swift-XRT observations
  9. Swift GRB220618.38: Global MASTER-Net observations report
  10. GRB 220617B: Swift ToO observations
  11. Fermi GRB 220617A: Global MASTER-Net observations report
  12. GRB 220611A: Gemini Ks counterpart detection
  13. Fermi trigger No 677174940: Global MASTER-Net observations report
  14. GRB 220611A: Gemini South Infrared Detection
  15. GRB 220611A: Swift/UVOT Upper Limits
  16. Fermi trigger No 676909037: Global MASTER-Net observations report
  17. Swift GRB 220611A: Global MASTER-Net observations report
  18. Fermi GRB 220610A: Global MASTER-Net observations report
  19. Fermi trigger No 676537486: Global MASTER-Net observations report
  20. Fermi trigger No 676366592: Global MASTER-Net observations report
  21. Fermi GRB 220608A: Global MASTER-Net observations report
  22. GRB 220606B: Gemini South Optical Observations
  23. MAXI GRB220607.31: Global MASTER-Net observations report
  24. MAXI GRB220607.41: Global MASTER-Net observations report
  25. GRB 220606B: Swift follow-up observations
  26. GRB 220527A: A BdHN I with a clear UPE phase
  27. GRB 220606B: Swift ToO observations
  28. GRB 220606B: Swift/BAT-GUANO candidate arcminute localization of a short burst
  29. Fermi GRB 220606B: Global MASTER-Net observations report
  30. Fermi trigger No 675992935: Global MASTER-Net observations report
  31. GRB 220527A: MITSuME Akeno continued optical observation
  32. GRB 220527A: Lick 3m Optical Observations
  33. Fermi GRB 220530A: Global MASTER-Net observations report
  34. GRB 220527A: REM optical/NIR observations
  35. GRB 220527A: VLT/X-shooter spectroscopic redshift
  36. GRB 220527A: MeerLICHT afterglow observations
  37. Fermi trigger No 675411172: Global MASTER-Net observations report
  38. LAT GRB220527.39: Global MASTER-Net observations report
  39. GRB 220527A: Swift/UVOT detection
  40. GRB 220527A: Swift-XRT afterglow detection
  41. GRB 220527A: Swift ToO observations
  42. Swift GRB220526.48: Global MASTER-Net observations report
  43. Fermi GRB 220525A: Global MASTER-Net observations report
  44. Fermi-LAT Gamma-ray Observations of IceCube-220524A
  45. GRB 220521A: ATCA detection
  46. GRB 220521A: ALMA detection
  47. GRB 220521A: ISON-Castelgrande observatory optical observations
  48. Fermi GRB 220523B: Global MASTER-Net observations report
  49. GRB 220521A: Gemini Observations
  50. GRB 220521A: MMT Afterglow Imaging
  51. GRB 220521A: REM optical/NIR upper limits
  52. VLA observations of GW170817 at ~4.8 years after the merger
  53. Fermi GRB 220523A: Global MASTER-Net observations report
  54. GRB 220521A: RATIR Optical and NIR Observations
  55. GRB 220521A: Swift/UVOT Upper Limits
  56. Fermi GRB 220522A: Global MASTER-Net observations report
  57. Fermi trigger No 674868783: Global MASTER-Net observations report
  58. GRB 220521A: SAO RAS optical observations
  59. Swift GRB220521.97: Global MASTER-Net observations report
  60. Swift GRB220519.84: Global MASTER-Net observations report
  61. Fermi GRB 220518B: Global MASTER-Net observations report
  62. Continued Chandra monitoring of GW170817 at ~4.8 yr post-merger
  63. GRB 220518A: Swift/UVOT Detection
  64. Swift GRB 220518A: Global MASTER-Net observations report
  65. GRB 220514A: GRANDMA Optical Afterglow Observations
  66. Fermi trigger No 674397342: Global MASTER-Net observations report
  67. GRB 220514B: Swift-XRT observations
  68. GRB 220511A: Swift-XRT afterglow detection
  69. GRB 220514A: KAIT Optical Afterglow Confirmation
  70. Fermi-LAT Gamma-ray Observations of IceCube-220513A
  71. GRB 220514B: Tiled Swift observations
  72. MAXI GRB220514.98: Global MASTER-Net observations report
  73. Integral GRB220514.52: Global MASTER-Net observations report
  74. Fermi GRB 220514A: Global MASTER-Net observations report
  75. IceCube-220513A: No Candidate Counterparts from the Zwicky Transient Facility
  76. IceCube Alert 220513.97: Global MASTER-Net observations report
  77. Fermi GRB 220513A: Global MASTER-Net observations report
  78. GRB 220427A: MeerLICHT afterglow observations
  79. GRB 220511A: Swift-XRT observations
  80. Fermi GRB 220512A: Global MASTER-Net observations report
  81. GRB 220511A: Swift ToO observations
  82. GRB 220511A: Swift/BAT-GUANO arcminute localization
  83. Fermi GRB 220511A: Global MASTER-Net observations report
  84. Fermi-LAT Gamma-ray Observations of IceCube-220509A
  85. Fermi trigger No 673846271: Global MASTER-Net observations report
  86. IceCube Alert 220509.76: Global MASTER-Net observations report
  87. Fermi trigger No 673610950: Global MASTER-Net observations report
  88. GRB 220506A: Swift-XRT afterglow detection
  89. GRB 220506A: Tiled Swift observations
  90. IceCube-220405B - ZTF19aavnpjv unrelated
  91. Swift-BAT triggers 1105560-1 are not GRBs
  92. Swift GRB220506.51: Global MASTER-Net observations report
  93. MAXI GRB220506.27: Global MASTER-Net observations report
  94. GRB 220430A: Nanshan/NEXT optical upper limit
  95. GRB 220430A: Nanshan/HMT optical upper limit
  96. GRB 220427A: LCO Optical Observations
  97. Fermi-LAT Gamma-ray Observations of IceCube-220501A
  98. GRB 220427A: GRANDMA Early Optical Afterglow Detection
  99. IceCube-220501A: No Candidate Counterparts from the Zwicky Transient Facility
  100. IceCube Alert 220501.95: Global MASTER-Net observations report

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