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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"

37775 results found.

  1. LIGO/Virgo S190426c: Fermi-LAT search for a high-energy gamma-ray counterpart
  2. GRB 190427A: CALET Gamma-Ray Burst Monitor detection
  3. LIGO/Virgo S190425z: RATIR non-detection of the Swift/UVOT source
  4. GRB 190427A: Swift/UVOT Upper Limits
  5. Fermi Trigger 578170097 / GRB 190428783 / GRB190428A: BALROG localization
  6. GRB 190427A, Swift-BAT refined analysis
  7. If you have problems wrt GCN ( GRB, LIGO/Virgo, etc) and need to send email to the operator
  8. GRB 190419A: AstroSat CZTI detection
  9. Fermi GRB190427.19 Global MASTER-Net observations report
  10. GRB 190427A: Fermi GBM detection
  11. GRB 190427A: Lick/Nickel telescope optical observations
  12. GRB 190427A: MITSuME Akeno optical upper limits
  13. GRB 190427A: COATLI Optical Observations
  14. GRB 190427A: RATIR Optical and NIR Observations
  15. LIGO/Virgo S190426c: Insight-HXMT/HE observation
  16. GRB 190427A: BOOTES-1 and BOOTES-5/JGT early follow-up observations
  17. LIGO/Virgo S190425z: Fermi-LAT search for a high-energy gamma-ray counterpart
  18. GRB 190427A: NOT optical observations
  19. GRB 190427A: Swift-XRT observations
  20. GRB 190427A: Swift detection of a short burst
  21. LIGO/Virgo S190426c: Swift/BAT Counterpart Search
  22. LIGO/Virgo S190426c: Fermi GBM Observations
  23. LIGO/Virgo S190426c: INTEGRAL prompt observation
  24. LIGO/Virgo S190425z: Insight-HXMT/HE observation
  25. LIGO/Virgo S190425z: Candidates from the Zwicky Transient Facility
  26. LIGO/Virgo S190425z: Fermi GBM Observations
  27. LIGO/Virgo S190425z: Swift/BAT Counterpart Search
  28. LIGO/Virgo S190425z: INTEGRAL IBIS prompt observation
  29. LIGO/Virgo S190425z: further analysis of INTEGRAL data
  30. LIGO/Virgo S190421ar: Fermi-LAT search for a high-energy gamma-ray counterpart
  31. LIGO/Virgo S190425z: INTEGRAL SPI-ACS prompt observation
  32. Fermi GRB190425.09 Global MASTER-Net observations report
  33. GRB 190424A: Swift-BAT refined analysis
  34. GRB 190424A: Swift detection of a burst
  35. GRB 190422A: Fermi GBM detection
  36. GRB 190422A: Swift/UVOT Upper Limits
  37. LIGO/Virgo S190421ar: Swift/BAT Counterpart Search
  38. GRB 190422A: Swift-BAT refined analysis
  39. GRB 190422A: Swift-XRT refined Analysis
  40. LIGO/Virgo S190421ar: INTEGRAL prompt observation
  41. GRB 190422A: Enhanced Swift-XRT position
  42. Fermi GRB190422.96 Global MASTER-Net observations report
  43. Fermi GRB190422.67 Global MASTER-Net observations report
  44. GRB 190422A: Swift detection of a burst
  45. LIGO/Virgo S190421ar: Fermi-GBM Observations
  46. Konus-Wind observation of GRB 190415A
  47. Fermi GRB190420.98 Global MASTER-Net observations report
  48. Fermi GRB190419.41 Global MASTER-Net observations report
  49. Fermi trigger 576241792 / GRB 190406B: MASTER optical observation
  50. Fermi Trigger 577360542 / GRB 190419414 / GRB190419A: BALROG localization
  51. Fermi GRB190418.92 Global MASTER-Net observations report
  52. GRB 190406B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 576241792)
  53. GRB 190326A: Swift XRT and UVOT follow-up observations
  54. IPN Triangulation of GRB 190415A
  55. Fermi GRB190417.46 Global MASTER-Net observations report
  56. GRB 190415A: Insight-HXMT/HE detection
  57. Fermi Trigger 576994194 / GRB 190415173 / : BALROG localization
  58. Fermi GRB190415.17 Global MASTER-Net observations report
  59. GRB 190407B: AstroSat CZTI detection
  60. Corrections: GRB 190404A (not 140404B ) and GRB 190404B (not 140404C)
  61. GRB 190411A: AstroSat CZTI detection
  62. GRB 190411A: Insight-HXMT/HE detection
  63. LIGO/Virgo S190412m: Fermi-LAT search for a high-energy gamma-ray counterpart
  64. LIGO/Virgo S190412m: Swift/BAT data search
  65. LIGO/Virgo S190412m: Fermi-GBM Observations
  66. LIGO/Virgo S190412m: Insight-HXMT/HE observation
  67. INTEGRAL prompt observation of S190412m
  68. IPN triangulation of GRB 190409B (short)
  69. GRB 190409A: ground analysis reveals a likely spurious event
  70. LIGO/Virgo S190408an: MAXI/GSC Observations
  71. GRB 190404C: MITSuME Akeno and Okayama optical upper limits
  72. Konus-Wind observation of GRB 190404B
  73. LIGO/Virgo ST190408an: Fermi-LAT search for a high-energy gamma-ray counterpart
  74. GRB 190409A: Swift detection of a possible burst
  75. LIGO/Virgo S190408an: Insight-HXMT/HE observation
  76. LIGO/Virgo S190408an: Swift/BAT data search
  77. CORRECTED TARGET NAME: GRB 190408A: MAXI/GSC detection
  78. GRB 140408A: MAXI/GSC detection
  79. INTEGRAL observation of S190408an
  80. LIGO/Virgo S190408an: Fermi GBM Observation
  81. GRB 190404C: Swift-XRT afterglow detection
  82. Fermi Gamma-ray Burst Monitor trigger 576420743/190408536 is not a GRB
  83. Fermi TriggNum 576054086 (GRB 1904204.29) / MASTER OT J071404.52+550304.2: CrAO optical observations
  84. Fermi Trigger 576356086 / GRB 190407788 / : BALROG localization
  85. Hard Fermi GRB190404.29/TriggNum576054086: MASTER optical counterpart discovery near PGC020455
  86. Fermi Trigger 576346051 / GRB 190407672 / GRB 190407A: BALROG localization
  87. GRB 190404B: CALET Gamma-Ray Burst Monitor detection
  88. GRB 190404C: Swift-XRT observations
  89. GRB 190331C: AstroSat CZTI detection
  90. Swift GRB 190331B: Further Swift-XRT observations
  91. GRB 190404B: Tiled Swift observations
  92. GRB 140404C: MAXI/GSC detection
  93. GRB 140404B: MAXI/GSC detection
  94. GRB 190330A: MITSuME Akeno and Okayama optical upper limits
  95. Konus-Wind observation of GRB 190329A
  96. GRB 190331B: BOOTES-3/YA optical observations
  97. GRB 190326B: AstroSat CZTI detection
  98. GRB 190331B: Swift observations of a ground-detected burst
  99. Fermi-LAT Gamma-ray Observations of IceCube-190331A
  100. GRB 190401A: Insight-HXMT/HE detection

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