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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"

21135 results found.

  1. GRB 210514A: Swift/UVOT Upper Limits
  2. Swift GRB210515.83: Global MASTER-Net observations report
  3. Fermi GRB 210515B: Global MASTER-Net observations report
  4. GRB 210514A: Swift-BAT refined analysis
  5. Fermi GRB 210515A: Global MASTER-Net observations report
  6. Swift GRB210514.71: Global MASTER-Net observations report
  7. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEM-210515A and 210515B
  8. GRB210510A: Optical afterglow candidate from the Zwicky Transient Facility
  9. Fermi trigger No 642538568: Global MASTER-Net observations report
  10. IceCube-210510A: not observable by Fermi-GBM
  11. Short GRB 210323A: likely host galaxy detection
  12. IceCube-210510A: No candidate counterparts from the Zwicky Transient Facility
  13. Fermi-LAT Gamma-ray Observations of IceCube-210510A
  14. Fermi GRB 210511A: Global MASTER-Net observations report
  15. Fermi GRB 210511B: Global MASTER-Net observations report
  16. Fermi GRB 210510A: Global MASTER-Net observations report
  17. IceCube Alert 210510.20: Global MASTER-Net observations report
  18. GRB 210509A: Swift/UVOT Upper Limits
  19. Swift GRB 210509A: Global MASTER-Net observations report
  20. GRB 210509A: BOOTES-4/MET optical upper limit
  21. GRB 210509A: Swift-XRT observations
  22. Fermi GRB 210507A: Global MASTER-Net observations report
  23. Fermi-LAT Gamma-ray Observations of IceCube-210503A and detection of a new gamma-ray source, Fermi J0931.9+3633
  24. ZTF21aayokph (AT2021lfa): continued Mondy optical observations
  25. Integral GRB210507.04: Global MASTER-Net observations report
  26. Integral GRB210506.78: Global MASTER-Net observations report
  27. GRB 210506A: Swift-XRT observations
  28. ZTF21aayokph (AT2021lfa): MASTER OT detection 3h befor ZTF
  29. Alert from the HAWC Burst Monitor HAWC-210507A
  30. GRB 210506A: TNG NIR upper limits
  31. ZTF21aayokph (AT2021lfa): Mondy and Koshka observatory optical observations
  32. ZTF21aayokph (AT2021lfa): X-ray Detection with Swift/XRT
  33. Lowell Discovery Telescope Observations of ZTF21aayokph (AT2021lfa)
  34. ZTF21aayokph (AT2021lfa): Assy optical observations
  35. GRB 210506A: Swift ToO observations
  36. GRB 210506A: Swift/BAT-GUANO detection and possible arcminute localization of a short hard burst
  37. GRB 210504A: Lowell Discovery Telescope optical observations
  38. ZTF21aayokph (AT2021lfa): Redshift from Gemini South
  39. RATIR Observations of ZTF21aayokph (AT2021lfa)
  40. DDOTI Observations of ZTF21aayokph (AT2021lfa)
  41. ZTF and LT observations of ZTF21aayokph (AT2021lfa), a fast-fading red transient
  42. GRB 210504A: NOT optical afterglow detection
  43. GRB 210504A: Swift/UVOT Detection
  44. Swift GRB210504.58: Global MASTER-Net observations report
  45. Fermi GRB 210503A: Global MASTER-Net observations report
  46. Swift GRB210502.74: Global MASTER-Net observations report
  47. MAXI GRB210501.83: Global MASTER-Net observations report
  48. Fermi GRB 210501A: Global MASTER-Net observations report
  49. Fermi trigger No 641601187: Global MASTER-Net observations report
  50. Fermi GRB 210430B: Global MASTER-Net observations report
  51. Swift GRB210430.45: Global MASTER-Net observations report
  52. GRB 210413B: Swift/UVOT Observations
  53. Delayed GRB GCN Notices from Swift
  54. GRB 210323B: Swift-XRT observations
  55. Fermi GRB 210427A: Global MASTER-Net observations report
  56. GRB 210420B: Assy optical observations
  57. Fermi trigger No 640975205: Global MASTER-Net observations report
  58. GRB 210420B: Zeiss-1000 of Koshka optical observations
  59. GRB 210421B: Swift-XRT observations
  60. GRB 210420B: continued Tautenburg observations
  61. Swift GRB210422.74: Global MASTER-Net observations report
  62. GRB 210421A: Swift/UVOT Upper Limits
  63. GRB 210421B: Swift ToO observations
  64. GRB 210421B: Swift/BAT-GUANO detection and arcminute localization
  65. Fermi GRB 210421C: Global MASTER-Net observations report
  66. GRB 210420B: Montarrenti Observatory follow-up observations
  67. Fermi trigger No 640695289: Global MASTER-Net observations report
  68. GRB 210419C: Swift/UVOT Upper Limits
  69. GRB 210420B: Ondrejov D50 optical afterglow detection
  70. GRB 210420B: RATIR Optical and NIR Observations
  71. GRB 210420B: Tautenburg observations
  72. GRB 210420B: Swift/UVOT Detection
  73. GRB 210420B: KAIT Optical Observations
  74. Fermi GRB 210420A: Global MASTER-Net observations report
  75. GRB 210420B: Redshift from GTC
  76. GRB 210420B: Montarrenti Observatory optical afterglow detection
  77. Swift GRB 210421A: Global MASTER-Net observations report
  78. GRB 210420B: BOOTES-4/MET optical afterglow detection
  79. GRB 210420B: Optical observations
  80. GRB 210419C: Montarrenti Observatory Upper Limit
  81. GRB 210419A: Swift/UVOT Upper Limits
  82. Swift GRB210419.98: Global MASTER-Net observations report
  83. Fermi GRB 210419B: Global MASTER-Net observations report
  84. Swift GRB 210419A: Global MASTER-Net observations report
  85. GRB 210413B: Swift-XRT observations
  86. IceCube Alert 210416.09: Global MASTER-Net observations report
  87. GRB 210413B: Swift ToO observations
  88. GRB 210413B: Swift/BAT detection and probable localization of a short burst
  89. GRB 210410A: A twin of short GRB 090510 with complementary observations
  90. Fermi GRB 210415A: Global MASTER-Net observations report
  91. GRB 210411C: Swift/UVOT Detection
  92. GRB 210411C: Chilescope optical observations
  93. GRB 210411C: ePESSTO+ NTT optical observations
  94. Swift GRB 210411C: Global MASTER-Net observations report
  95. GRB 210411C: BOOTES-4/MET optical upper limit
  96. Fermi GRB 210411B: Global MASTER-Net observations report
  97. GRB 210406A: 10.4m GTC follow-up observation
  98. Fermi GRB 210411A: Global MASTER-Net observations report
  99. GRB 210410A: Swift/UVOT Upper Limits
  100. GRB 210406A: Swift-XRT observations

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