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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"

6829 results found.

  1. GRB 190512A: Fermi GBM observation
  2. GRB 190511A: Swift-XRT refined Analysis
  3. GRB 190511A: Swift/UVOT Detection
  4. GRB 190511A: Fermi-LAT detection
  5. GRB 190511A: Fermi GBM observation
  6. LIGO/Virgo S190510g: Unconfirmed OT in PGC 094244
  7. LIGO/Virgo S190510g: MASTER possible OT in PGC094244 galaxy
  8. LIGO/Virgo S190510g: J-GEM optical/NIR follow-up observations
  9. LIGO/Virgo S190510g: Fermi-LAT search for a high-energy gamma-ray counterpart
  10. GRB 190501A: Swift XRT and UVOT Observations
  11. LIGO/Virgo S190426c: Konus-Wind observations
  12. LIGO/Virgo S190425z: Konus-Wind observations
  13. Fermi-LAT Gamma-ray Observations of IceCube-190504A
  14. LIGO/Virgo S190503bf: Fermi-LAT search for a high-energy gamma-ray counterpart
  15. Fermi-LAT Gamma-ray Observations of IceCube-190503A
  16. IceCube-190503A: INTEGRAL prompt observation
  17. LIGO/Virgo S190503bf: INTEGRAL prompt observation
  18. LIGO/Virgo S190425z: Insight-HXMT observation and counterpart search
  19. LIGO/Virgo S190412m: Further J-GEM optical/NIR observations
  20. LIGO/Virgo S190425z: KPED Follow-Up of ZTF transients
  21. LIGO/Virgo S190426c: Fermi-LAT search for a high-energy gamma-ray counterpart
  22. LIGO/Virgo S190425z: VISTA K-band observations of the Swift/UVOT Transient
  23. LIGO/Virgo S190425z : IRSF/SIRIUS NIR photometric follow-up observation of the Swift/UVOT Transient
  24. LIGO/Virgo S190425z: KPED Follow-Up of ZTF transients
  25. LIGO/Virgo S190425z: Swift/UVOT and XRT pre-images at the position of the potential Swift/UVOT counterpart
  26. GRB 190427A: Fermi GBM detection
  27. LIGO/Virgo S190426c: Swift-XRT sources
  28. LIGO/Virgo S190425z: Fermi-LAT search for a high-energy gamma-ray counterpart
  29. GRB 190427A: NOT optical observations
  30. LIGO/Virgo S190426c: INTEGRAL prompt observation
  31. LIGO/Virgo S190425z : IRSF/SIRIUS NIR photometry of ZTF19aarykkb and ZTF19aarzaod
  32. LIGO/Virgo S190425z - GROWTH-India follow-up of two ZTF candidates
  33. LIGO/Virgo S190425z: KPED Follow-Up Observations
  34. LIGO/Virgo S190425z: Lulin Follow-Up Observations
  35. LIGO/Virgo S190425z: AGILE-GRID Observations
  36. LIGO/Virgo S190421ar: Fermi-LAT search for a high-energy gamma-ray counterpart
  37. GRB 190422A: Fermi GBM detection
  38. GRB 190422A: Swift-XRT refined Analysis
  39. LIGO/Virgo S190421ar: INTEGRAL prompt observation
  40. LIGO/Virgo S190408an: INTEGRAL follow-up observations
  41. GRB 190326A: Swift XRT and UVOT follow-up observations
  42. LIGO/Virgo S190412m: Fermi-LAT search for a high-energy gamma-ray counterpart
  43. INTEGRAL prompt observation of S190412m
  44. GRB 190409A: ground analysis reveals a likely spurious event
  45. LIGO/Virgo ST190408an: Fermi-LAT search for a high-energy gamma-ray counterpart
  46. GRB 190409A: Swift detection of a possible burst
  47. INTEGRAL observation of S190408an
  48. GRB 190404C: Swift-XRT afterglow detection
  49. GRB 190404C: Swift-XRT observations
  50. Swift GRB 190331B: Further Swift-XRT observations
  51. GRB 190331B: Swift observations of a ground-detected burst
  52. Fermi-LAT Gamma-ray Observations of IceCube-190331A
  53. GRB 190331A: Fermi GBM detection
  54. MAGIC follow-up of the X-ray flares of LS I +61�303 dete
  55. GRB 190326B: Fermi GBM detection
  56. GRB 190324A: Swift-XRT refined Analysis
  57. GRB 190324A: Fermi GBM observation
  58. Further Chandra observations of GW170817 ~581-583 days since merger
  59. GRB 190320A: Swift-XRT refined Analysis
  60. GRB 190320A: Fermi GBM observation
  61. GRB 190311A: Fermi GBM observation
  62. GRB 190311A: Swift-XRT refined Analysis
  63. GRB 190311A: NEXT-0.6m optical afterglow detection
  64. GRB 190305A: Swift-XRT afterglow detection
  65. GRB 190306A: Swift-XRT observations
  66. GRB 190305A: Swift-XRT observations
  67. INTEGRAL observation of IceCube-190221A
  68. IceCube-190221A: Fermi-LAT Gamma-ray observations
  69. GRB 190220B: Fermi GBM observation
  70. GRB 190220A: Swift-XRT refined Analysis
  71. GRB 190219A: Swift-XRT refined Analysis
  72. GRB 190215A: Fermi GBM detection
  73. GRB 190211A: DOAO optical observation
  74. GRB 190211A: Swift-XRT refined Analysis
  75. GRB 190211A: NEXT-0.6m optical afterglow detection
  76. GRB 190202A: SAO RAS further optical observations
  77. GRB 190204A: SAO RAS optical observations
  78. GRB 190203A: Swift-XRT refined Analysis
  79. GRB 190204A: Swift-XRT refined Analysis
  80. GRB 190202A: R and I band observation from HCT
  81. GRB 190203A: SAO RAS optical observations, afterglow fading
  82. GRB 190202A: SAO RAS optical observations
  83. GRB 190202A: Swift-XRT refined Analysis
  84. GRB 190202A: Fermi GBM observation
  85. GRB 190129B: Swift-XRT candidate afterglow detection
  86. Fermi GBM Observations of IceCube-190124A
  87. GRB 190129A: Fermi GBM detection
  88. INTEGRAL observation of IceCube-190124A
  89. Fermi-LAT Gamma-ray Observations of IceCube-190124A
  90. GRB 190123A: Swift-XRT refined Analysis
  91. GRB 190123A: Fermi GBM observation
  92. GRB 190122A: Fermi GBM observation
  93. GRB 190122A: Fermi-LAT detection
  94. GRB 190114C: RTT150 optical observations
  95. GRB 190114B: Swift-XRT refined Analysis
  96. GRB 190114C: Mondy optical observations
  97. GRB 190114C: A type 1 BdHN with TeV emission
  98. GRB 190114C: Fermi-LAT detection
  99. GRB 190114C: Fermi GBM detection
  100. GRB 190114C: Swift-XRT refined Analysis

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