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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"

21131 results found.

  1. Swift GRB 201020A: Global MASTER-Net observations report
  2. GRB 201014A: SAO RAS optical observations
  3. GRB 201017A: SAO RAS optical observations
  4. GRB 201014A: 3.6m DOT Optical Observations
  5. GRB 201015A: 6 GHz VLA radio afterglow candidate detection
  6. GRB 201013A: 3.6m DOT Optical Observations
  7. GRB 201014A: MMT afterglow detection
  8. GRB 201015A: HCT optical photometric follow-up
  9. GRB 201017A: Assy and Mondy optical observations, possible afterglow detection
  10. GRB 201015A: Xinglong-2.16m optical observations
  11. GRB 201015A: MMT afterglow imaging
  12. GRB 201015A: Assy and Mondy optical observations
  13. GRB 201015A: classification as long GRB
  14. Swift GRB 201017A: Global MASTER-Net observations report
  15. GRB 201015A: Swift/UVOT Detection
  16. GRB 201015A: redshift confirmation
  17. MAGIC observations of GRB 201015A: hint of very high energy gamma-ray signal
  18. GRB 201015A: Swift-BAT refined analysis (a soft short pulse with a tail emission)
  19. GRB 201015A: CrAO/ZTSH optical observations
  20. GRB 201014A: Nanshan/NEXT optical observations
  21. GRB 201014A: Lowell Discovery Telescope afterglow imaging
  22. GRB201015A: Nanshan/NEXT early optical observations
  23. GRB 201008A: Swift-XRT afterglow detection
  24. GRB 201014A: Swift/UVOT Upper Limits
  25. Fermi GRB 201016B: Global MASTER-Net observations report
  26. GRB 201015A: GOTO confirmation of afterglow detection
  27. GRB 201015A: Swift-XRT observations
  28. Swift GRB 201015A: Global MASTER-Net observations report
  29. IceCube Alert 201014.09: Global MASTER-Net observations report
  30. Fermi-LAT Gamma-ray Observations of IceCube-201014A
  31. GRB 201013A: TSHAO and AbAO optical observations, afterglow confirmation
  32. IceCube-201014A: Not observable by GBM
  33. GRB 201013A: Swift/UVOT Upper Limits
  34. Swift GRB 201013A: Global MASTER-Net observations report
  35. SGR 1830-0645: Swift/UVOT Upper Limits
  36. IceCube-201007A: No candidate counterparts from the Zwicky Transient Facility
  37. Fermi trigger No 624139481: Global MASTER-Net observations report
  38. Fermi trigger No 624121589: Global MASTER-Net observations report
  39. GRB 201006A: Chandra upper limit on the X-ray afterglow
  40. Swift GRB201010.62: Global MASTER-Net observations report
  41. IceCube-200929A: JCMT/SCUBA2 observations
  42. GRB 201008A: Swift-XRT observations
  43. IceCube-200926A: Upper limits from Insight-HXMT Observations
  44. GRB 201008A: Swift ToO observations
  45. IceCube-201007A: Upper limits from Fermi-GBM Observations
  46. GRB 201008A: Swift/BAT-GUANO detection and possible arcminute localization
  47. Fermi-LAT Gamma-ray Observations of IceCube-201007A
  48. Fermi trigger No 623846261: Global MASTER-Net observations report
  49. Fermi trigger No 623873165: Global MASTER-Net observations report
  50. Swift-XRT observations of IceCube 201007A
  51. Baksan Neutrino Observatory Alert 201008.47: Global MASTER-Net observations report
  52. IceCube Alert 201007.92: Global MASTER-Net observations report
  53. GRB 201006A: GROWTH-India Telescope optical upper limit
  54. GRB 201006A: Lowell Discovery Telescope upper limits
  55. Fermi GRB 201007A: Global MASTER-Net observations report
  56. Baksan Neutrino Observatory Alert 201006.88: Global MASTER-Net observations report
  57. GRB 201006A: Swift/UVOT Upper Limits
  58. Swift GRB201006.05: Global MASTER-Net observations report
  59. Fermi trigger No 623470566: Global MASTER-Net observations report
  60. Fermi trigger No 623493962: Global MASTER-Net observations report
  61. GRB 201001A: Swift/UVOT Upper Limits
  62. IceCube-200926A: No candidate counterparts from the Zwicky Transient Facility
  63. GRB 201001A: TSHAO optical upper limit
  64. GRB 201001A: Xinglong-2.16m optical upper limit
  65. IceCube-200926A: JCMT/SCUBA2 observations
  66. Swift-XRT observations of IceCube 200929A
  67. Fermi-LAT Gamma-ray Observations of IceCube-200929A
  68. IceCube-200929A: Upper limits from Fermi-GBM Observations
  69. IceCube-200926B: Upper limits from Fermi-GBM Observations
  70. IceCube-200926A: Upper limits from Fermi-GBM Observations
  71. IceCube Alert 200929.74: Global MASTER-Net observations report
  72. Fermi GRB 200929A: Global MASTER-Net observations report
  73. IceCube-200926A: No Candidate Counterparts from the Zwicky Transient Facility
  74. Fermi-LAT Gamma-ray Observations of IceCube-200926B
  75. IceCube Alert 200926.94: Global MASTER-Net observations report
  76. Swift-XRT observations of IceCube 200926A
  77. Fermi-LAT Gamma-ray Observations of IceCube-200926A
  78. IceCube Alert 200926.33: Global MASTER-Net observations report
  79. GRB 200925B: Swift/UVOT Detection
  80. GRB 200922A: Chilescope optical observations
  81. Swift GRB 200925B: Global MASTER-Net OT detection
  82. Swift GRB200925.91: Global MASTER-Net observations report
  83. Fermi GRB 200925A: Global MASTER-Net observations report
  84. Fermi GRB 200924A: Global MASTER-Net observations report
  85. GRB 200922A: chance superposition between optical afterglow and archival star
  86. Fermi trigger No 622618714: Global MASTER-Net observations report
  87. Fermi GRB 200923A: Global MASTER-Net observations report
  88. IceCube Alert 200921.80: Global MASTER-Net observations report
  89. GRB 200922A: Swift/UVOT Detection
  90. Fermi-LAT Gamma-ray Observations of IceCube-200921A and detection of a new gamma-ray source, Fermi J1256.9+2630
  91. IceCube-200921A: no significant detection in HAWC observations
  92. Fermi GRB 200922B: Global MASTER-Net observations report
  93. GRB 200922A: LCO observations
  94. Swift GRB 200922A: Global MASTER-Net observations report
  95. GRB 200917A: Swift/UVOT Upper Limits
  96. IceCube-200921A: Upper limits from Fermi-GBM Observations
  97. GRB 200914A: Swift-XRT further observations
  98. Fermi GRB 200919C: Global MASTER-Net observations report
  99. Fermi GRB 200919B: Global MASTER-Net observations report
  100. GRB 200916B: MASTER optical observation

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