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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"

45816 results found.

  1. GRB 240114A: MAXI/GSC detection
  2. GRB 240112C: Swift/UVOT Detection
  3. GRB 240112C: Fermi GBM Detection
  4. Fermi trigger No 726773850: Global MASTER-Net observations report
  5. GRB 240112C: Swift-XRT refined Analysis
  6. GRB 240112C: SAO RAS optical observations
  7. GRB 240112E: Fermi GBM Final Localization
  8. Fermi GRB 240112D: Global MASTER-Net observations report
  9. GRB 240112D: Fermi GBM Final Real-time Localization
  10. Fermi trigger No 726774492: Global MASTER-Net observations report
  11. Swift GRB 240112C: Global MASTER-Net observations report
  12. Fermi GRB 240112B: Global MASTER-Net observations report
  13. GRB 240109A: Swift-BAT refined analysis
  14. GRB 240112C: Swift detection of a burst with an optical counterpart
  15. GRB 240112B: Fermi GBM Final Real-time Localization
  16. GRB 240112A: GECAM detection of a burst
  17. GRB 240109A: Fermi GBM Observation
  18. GRB 240110A: AstroSat CZTI detection
  19. Fermi-LAT detection of increased gamma-ray activity of blazar PKS 0446+11, located inside the IceCube-240105A error region
  20. GRB 240108A: Glowbug gamma-ray detection
  21. GRB 231214A: ATCA Radio Upper Limits
  22. GRB 240106B: Glowbug gamma-ray detection
  23. GRB 240106A: Glowbug gamma-ray detection
  24. IceCube-240105A: Upper limits from a search for additional neutrino events in IceCube
  25. GRB 240109B: Fermi GBM Final Real-time Localization
  26. IceCube-240105A: Three candidates from the Zwicky Transient Facility
  27. LIGO/Virgo/KAGRA S240109a: Updated Sky localization
  28. Konus-Wind detection of GRB 240101C
  29. GRB 231215A: radio detection with the VLA
  30. GRB 230818A: further radio observations with the VLA
  31. GRB 230812B: further radio observations with the VLA
  32. Swift GRB240109.17: Global MASTER-Net observations report
  33. GRB 240107A: AstroSat CZTI detection
  34. LIGO/Virgo/KAGRA S240109a: Identification of a GW compact binary merger candidate
  35. GRB 240109A: Swift detection of a short burst
  36. LIGO/Virgo/KAGRA S240104bl: Upper limits from Swift/BAT-GUANO
  37. IceCube-240105A: JCMT SCUBA2 Detection of Two Bright Submillimeter Sources
  38. Update of IceCube-240105A - Corrected errors
  39. GRB 240106A: GRBAlpha detection
  40. LIGO/Virgo/KAGRA S240107b: Updated Sky localization and Source Classification
  41. GRB 240107A: MAXI/GSC detection
  42. Fermi trigger No 726347794: Global MASTER-Net observations report
  43. LIGO/Virgo/KAGRA S240107b: Identification of a GW compact binary merger candidate
  44. GRB 240106B: Fermi GBM Final Real-time Localization
  45. Fermi trigger No 726194053: Global MASTER-Net observations report
  46. GRB 240106A: Fermi GBM Final Real-time Localization
  47. IPN triangulation of GRB 240101C (short)
  48. GRB GRB240101C: Fermi GBM observation
  49. IceCube Alert 240105.52: Global MASTER-Net observations report
  50. GRB 240101A: 1.3m DFOT optical observations
  51. IceCube-240105A - IceCube observation of a high-energy neutrino candidate track-like event
  52. GRB 240102A: 1.3m DFOT optical upper limit
  53. GRB 240101B: 1.3m DFOT optical upper limit
  54. GRB 240101C: Swift/BAT-GUANO detection of a short burst
  55. LIGO/Virgo/KAGRA S240104bl: Updated Sky localization
  56. LIGO/Virgo/KAGRA S240104bl: Identification of a GW compact binary merger candidate
  57. GRB 240102C: AstroSat CZTI detection
  58. GRB 240101C: AstroSat CZTI detection
  59. GRB 231220A: Swift-UVOT upper limit
  60. GRB 240102A: Swift-BAT refined analysis
  61. GRB 240102A: Swift/UVOT Upper Limits
  62. GRB 231230A: Swift-BAT refined analysis
  63. GRB 240101A: Swift-BAT refined analysis
  64. GRB 240101B: Swift-BAT refined analysis
  65. GRB 240102A: Enhanced Swift-XRT position
  66. GRB 240101B: Swift-XRT refined Analysis
  67. GRB 240102A: Swift-XRT refined Analysis
  68. GRB 240102B (Fermi GBM trigger 725926335/240102925) is not a GRB
  69. GRB 240102A: LCOGT Optical Upper Limits
  70. Fermi trigger No 725857207: Global MASTER-Net observations report
  71. GRB240102A: BOOTES-6/DPRT optical upper limit
  72. GRB 240102B: Fermi GBM Final Real-time Localization
  73. GRB 240101B: MarSEC Observatory, Vicenza, Italy, UPPER LIMIT
  74. IceCube-Cascade 231230A: Upper limits from a search for additional neutrino events in IceCube
  75. GRB 240102A: Swift detection of a burst
  76. GRB 240101A: Terskol Zeiss-2000 optical observations
  77. GRB 240101C: GRBAlpha detection
  78. GRB 240101B: Swift/UVOT Upper Limits
  79. GRB 240101A: Swift/UVOT Upper Limits
  80. GRB 240101A: Swift-XRT refined Analysis
  81. GRB 240101B: Enhanced Swift-XRT position
  82. GRB 240101B: KAIT Optical Upper Limit
  83. GRB 240101A: KAIT Optical Upper Limit
  84. GRB 240101A: Enhanced Swift-XRT position
  85. GRB 240101C: Fermi GBM Final Localization
  86. Swift GRB240101.85: Global MASTER-Net observations report
  87. GRB 240101B: Swift detection of a burst
  88. GRB 240101A: Swift detection of a burst
  89. Fermi trigger No 725806648: Global MASTER-Net observations report
  90. LIGO/Virgo/KAGRA S231231ag: Updated Sky localization and Source Classification
  91. LIGO/Virgo/KAGRA S231231ag: Identification of a GW compact binary merger candidate
  92. GRB231230A: Fermi GBM Observation
  93. GRB 231230A: Swift-XRT refined Analysis
  94. GRB 231230A: GOTO optical upper limits
  95. GRB 231230A: Enhanced Swift-XRT position
  96. GRB 231230A: Swift/UVOT Upper Limits
  97. GRB 231230A: NOT optical upper limits
  98. Fermi trigger No 725592555: Global MASTER-Net observations report
  99. GRB 231230A: Prompt enhanced Swift-XRT position
  100. GRB 231230A: Swift detection of a burst

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