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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"

21138 results found.

  1. Fermi-LAT Gamma-ray Observations of IceCube-201221A
  2. IceCube-201222A: not observable by Fermi-GBM
  3. GRB 201221D: Archival PS1 Imaging of the Putative Host Galaxy
  4. GRB 201221D: Swift/UVOT Upper Limits
  5. GRB 201221D: Lowell Discovery Telescope afterglow observations
  6. IceCube Alert 201222.04: Global MASTER-Net observations report
  7. Swift GRB 201221D: Global MASTER-Net observations report
  8. Fermi GRB 201221E: Global MASTER-Net observations report
  9. GRB 201221D: Nanshan/NEXT early optical upper limit
  10. GRB 201221D: candidate optical counterpart from the NOT
  11. GRB 201221A: Swift/UVOT Upper Limits
  12. GRB 201221C: MASTER optical observtion
  13. IceCube-201221A: not observable by Fermi-GBM
  14. Swift GRB 201221A: Global MASTER-Net observations report
  15. GRB 201209A: Mondy optical observations, afterglow confirmation
  16. GRB 201214A: Swift-XRT afterglow detection
  17. Fermi GRB 201218B: Global MASTER-Net observations report
  18. Fermi GRB 201218A: Global MASTER-Net observations report
  19. GRB 201216C: Liverpool Telescope First Hour Observations
  20. Fermi GRB 201217A: Global MASTER-Net observations report
  21. GRB 201216C: VLT X-shooter spectroscopy and potential high redshift of a VHE-emitting GRB
  22. GRB 201216C: MAGIC detection in very high energy gamma rays
  23. GRB 201216C: Swift/UVOT Upper Limits
  24. GRB 201216C: FRAM-ORM afterglow confirmation
  25. GRB 201216A: Swift-XRT observations
  26. Baksan Neutrino Observatory Alert 201216.94: Global MASTER-Net observations report
  27. GRB 201216C: VLT afterglow candidate discovery
  28. GRB 201216A: Swift ToO observations
  29. GRB 201216C: Swift-XRT observations
  30. Swift GRB201216.96: Global MASTER-Net observations report
  31. Fermi GRB 201216A: Global MASTER-Net observations report
  32. GRB 201216A: Swift/BAT-GUANO detection and arcminute localization
  33. Chandra observations of GW170817 at ~3.3 years since merger (Full report)
  34. GRB 201214B: Lowell Discovery Telescope optical observations
  35. VLA observations of GW170817 at ~3.3 years post-merger
  36. GRB 201214B: Swift-XRT observations
  37. Fermi GRB 201215A: Global MASTER-Net observations report
  38. IceCube-201209A: Upper limits from Insight-HXMT/HE observations
  39. GRB 201214A: Swift-XRT observations
  40. GRB 201214B: Swift BAT location of short burst
  41. Fermi GRB 201214B: Global MASTER-Net observations report
  42. GRB 201214B: Swift ToO observations
  43. Potential X-ray KN afterglow from Chandra observations of GW170817 ~3.3 years since merger (3 Epochs of 4)
  44. Long-lasting X-ray emission from GW170817 detected by Chandra
  45. GRB 201214A: Swift ToO observations
  46. Integral GRB201214.26: Global MASTER-Net observations report
  47. GRB 201015A: optical observations and supernova identification
  48. GRB 201203A: Zeiss-1000 (Koshka observatory) optical upper limit
  49. IceCube-201209A: No Candidate Counterparts from the Zwicky Transient Facility
  50. GRB 200826A: GMOS-N detected source magnitude (Correction)
  51. GRB 201209A: Swift/UVOT Upper Limits
  52. IceCube-201209A: Upper limits from Fermi-GBM Observations
  53. Fermi-LAT Gamma-ray Observations of IceCube-201209A
  54. IceCube Alert 201209.43: Global MASTER-Net observations report
  55. Chandra observations of GW170817 at ~3.3 years since merger (Observation 1 of 4)
  56. GRB 201208A: Swift-XRT afterglow detection
  57. GRB 201208A: LCO observations
  58. GRB 201209A: Xinglong-2.16m likely optical afterglow detection
  59. IceCube-201130A: Optical and NIR Imaging Follow-up by Kanata Telescope
  60. GRB 201209A: KAIT Optical Upper Limit
  61. Swift GRB201209.24: Global MASTER-Net observations report
  62. GRB 201208A: Swift ToO observations
  63. Fermi GRB 201208A: Global MASTER-Net observations report
  64. Fermi GRB 201207A: Global MASTER-Net observations report
  65. Swift follow-up observations of the flat spectrum radio quasar PMN J0206-1150 in the error region of IceCube-201130A
  66. Swift GRB 201203A: Global MASTER-Net observations report
  67. GRB 201203A: Swift-XRT afterglow detection
  68. IceCube-201130A: No Candidate Counterparts from the Zwicky Transient Facility
  69. GRB 201203A: KAIT Optical Upper Limit
  70. GRB 201203A: DDOTI Observations
  71. GRB 201128B: Swift-XRT observations
  72. Swift observations of the Fermi-LAT source 4FGL J0206.4-1151 in the error region of IceCube-201130A
  73. Fermi-LAT Gamma-ray Observations of IceCube-201130A
  74. IceCube-201130A: Not observable by Fermi-GBM
  75. GRB 201201A: DDOTI Observations
  76. Fermi GRB 201201A: Global MASTER-Net observations report
  77. GRB 201128B: Swift ToO observations
  78. Swift-XRT observations of IceCube 201130A
  79. GRB 201128B: Swift/BAT-GUANO detection and arcminute localization
  80. GRB 201128A: Swift/UVOT Upper Limits
  81. IceCube Alert 201130.85: Global MASTER-Net observations report
  82. GRB 201130A: DDOTI Observations
  83. Fermi GRB 201130A: Global MASTER-Net observations report
  84. Baksan Neutrino Observatory Alert 201128.90: Global MASTER-Net observations report
  85. Fermi trigger No 628278856: Global MASTER-Net observations report
  86. GRB 201128A: DDOTI Observations
  87. Fermi trigger No 628140709: DDOTI/OAN optical observations report
  88. Fermi trigger No 628140709: Global MASTER-Net observations report
  89. IceCube-201114A: Updated photometry for three DECam candidate optical counterparts
  90. IceCube Alert 201124.34: Global MASTER-Net observations report
  91. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-201124A
  92. GRB 200826A: TNG and LBT constraints on a supernova bump
  93. IceCube-201114A: DECam observations and candidate optical counterpart
  94. GRB 201015A L-band observations with e-MERLIN
  95. Fermi-LAT Gamma-ray Observations of IceCube-201120A
  96. Fermi trigger No 627645769: Global MASTER-Net observations report
  97. GRB 201015A radio afterglow with e-MERLIN
  98. Fermi GRB 201121A: Global MASTER-Net observations report
  99. Fermi GRB 201120B: Global MASTER-Net observations report
  100. IceCube-201120A: Upper limits from Fermi-GBM Observations

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