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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"

11856 results found.

  1. GRB 210512.786: DDOTI Upper Limits on the Afterglow
  2. Fermi trigger No 642538568: Global MASTER-Net observations report
  3. Fermi-LAT Gamma-ray Observations of IceCube-210510A
  4. Fermi GRB 210511A: Global MASTER-Net observations report
  5. Fermi GRB 210511B: Global MASTER-Net observations report
  6. GRB 210511B: AGILE detection
  7. Fermi GRB 210510A: Global MASTER-Net observations report
  8. IceCube Alert 210510.20: Global MASTER-Net observations report
  9. GRB 210510A: Fermi GBM Final Real-time Localization
  10. GRB 210509A: Swift-XRT refined Analysis
  11. Swift GRB 210509A: Global MASTER-Net observations report
  12. GRB 210509A: Swift-XRT observations
  13. GRB 210509A: Swift detection of a burst
  14. Fermi GRB 210507A: Global MASTER-Net observations report
  15. Fermi-LAT Gamma-ray Observations of IceCube-210503A and detection of a new gamma-ray source, Fermi J0931.9+3633
  16. ZTF21aayokph (AT2021lfa): Assy optical observations
  17. GRB 210424B: AstroSat CZTI detection
  18. GRB 210504A: Swift/UVOT Detection
  19. Fermi GRB 210503A: Global MASTER-Net observations report
  20. Fermi GRB 210501A: Global MASTER-Net observations report
  21. Fermi trigger No 641601187: Global MASTER-Net observations report
  22. GRB 210430A: BOOTES-1 optical limit
  23. Konus-Wind detection of GRB 210424B
  24. IPN triangulation of GRB 210424B (short/hard)
  25. Fermi GRB 210427A: Global MASTER-Net observations report
  26. GRB 210420B: Assy optical observations
  27. Fermi trigger No 640975205: Global MASTER-Net observations report
  28. GRB 210424.694: DDOTI Upper Limits on the Afterglow
  29. GRB 210420B: follow-up photometry of optical afterglow at INASAN/Simeiz
  30. GRB 210420B: Zeiss-1000 of Koshka optical observations
  31. GRB 210421B: AstroSat CZTI detection
  32. GRB 210421A: GECAM detection
  33. GRB 210421B: AstroSat CZTI detection
  34. Swift GRB210422.74: Global MASTER-Net observations report
  35. Fermi Gamma-ray Burst Monitor trigger 210421C is not a GRB
  36. GRB 210420B: Swift-XRT refined Analysis
  37. GRB 210421C: Fermi GBM Final Real-time Localization
  38. GRB 210420B: Tautenburg observations
  39. GRB 210420B: Swift/UVOT Detection
  40. GRB 210419C: MITSuME Akeno optical upper limits
  41. GRB 210420B: Montarrenti Observatory optical afterglow detection
  42. Swift GRB 210421A: Global MASTER-Net observations report
  43. GRB 210420B: BOOTES-4/MET optical afterglow detection
  44. GRB 210420B: MASTER optical counterpart detection
  45. GRB 210420B: Swift detection of a burst
  46. GRB 210419C: Montarrenti Observatory Upper Limit
  47. GRB 210420A: Fermi GBM Final Real-time Localization
  48. Swift GRB210419.98: Global MASTER-Net observations report
  49. GRB 210419A: Swift-XRT refined Analysis
  50. GRB 210419A: Swift detection of a burst
  51. GRB 210411B: AstroSat CZTI detection
  52. GRB 210410A: AstroSat CZTI detection
  53. GRB 210415A: Fermi GBM Final Real-time Localization
  54. GRB 210411C: Swift/UVOT Detection
  55. GRB 210411C: Swift-XRT refined Analysis
  56. GRB 210411C: BOOTES-4/MET optical upper limit
  57. Fermi GRB 210411B: Global MASTER-Net observations report
  58. GRB 210406A: 10.4m GTC follow-up observation
  59. Konus-Wind detection of GRB 210410A
  60. GRB 210411C: Swift detection of a burst with an optical counterpart
  61. Fermi GRB 210411A: Global MASTER-Net observations report
  62. GRB 210410A: Swift-XRT refined Analysis
  63. GRB 210409A: GECAM detection
  64. GRB 210410A: AGILE detection of a burst
  65. GRB 210410A: Fermi-LAT detection
  66. Fermi GRB 210410A: Global MASTER-Net observations report
  67. GRB 210406A: Mondy optical afterglow candidate
  68. GRB 210406B: Fermi GBM detection
  69. Konus-Wind detection of GRB 210406A
  70. GRB 210406A: A long GRB detected by INTEGRAL
  71. Integral GRB210406.72: Global MASTER-Net observations report
  72. GRB 210404.141: DDOTI Upper Limits
  73. GRB 210402A: Swift-XRT refined Analysis
  74. GRB 210330A: AstroSat CZTI detection
  75. GRB 210328A: AstroSat CZTI detection
  76. Konus-Wind detection of GRB 210401A
  77. GRB 210402A: Swift detection of a burst
  78. Fermi GRB 210401A: Global MASTER-Net observations report
  79. GRB 210328A: GECAM detection
  80. GRB 210330A: GECAM detection
  81. GRB 210324A: AstroSat CZTI detection
  82. GRB 210324C: AstroSat CZTI detection
  83. GRB 210328A: BALROG localization (Fermi Trigger / GRB 210328865)
  84. GRB 210328A: Fermi GBM Final Real-time Localization
  85. Konus-Wind detection of GRB 210324C
  86. Fermi GRB 210324C: Global MASTER-Net observations report
  87. Fermi GRB 210324B: Global MASTER-Net observations report
  88. Konus-Wind detection of GRB 210323A (short)
  89. Fermi GBM trigger 637977270/210320996 is not a GRB
  90. Konus-Wind detection of GRB 210321A
  91. IceCube Alert 210322.11: Global MASTER-Net observations report
  92. GRB 210321A: Mondy optical observations
  93. GRB 210321A: Redshift from OSIRIS/GTC
  94. GRB 210321A: NOT optical afterglow detection and redshift limit
  95. GRB 210320A: MAXI/GSC detection
  96. GRB 210318A: Swift-XRT refined Analysis
  97. Konus-Wind detection of GRB 210318B
  98. GRB210318B: Swift detection of a burst
  99. GRB 210318A: Swift detection of a burst
  100. Fermi trigger No 637521056: Global MASTER-Net observations report

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