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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"

21133 results found.

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

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