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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"

27301 results found.

  1. LIGO/Virgo S190521g: No candidate counterpart in Fermi-LAT observations
  2. LIGO/Virgo S190521r Global MASTER-Net observations report
  3. LIGO/Virgo S190521r: Coverage and upper limits from MAXI/GSC observations
  4. LIGO/Virgo S190517h : No counterpart candidate in TAROT-GRANDMA observations.
  5. LIGO/Virgo S190521r: No counterpart candidates in HAWC observations
  6. LIGO/Virgo S190519bj: Fermi-LAT search for a high-energy gamma-ray counterpart
  7. IGO/Virgo S190521g: Coverage and upper limits from MAXI/GSC observations
  8. LIGO/Virgo S190521g: No counterpart candidates in INTEGRAL SPI/ACS & IBIS/PICsIT prompt observations
  9. LIGO/Virgo S190521g: No counterpart candidates in HAWC observations
  10. LIGO/Virgo S190521g Global MASTER-Net observations report
  11. S190519bj: No transient candidates from CALET observations
  12. LIGO/Virgo S190519bj: Upper limits from Insight-HXMT/HE observations
  13. LIGO/Virgo S190512at: SVOM/GWAC-F60A observations
  14. Fermi GRB190520.6 Global MASTER-Net observations report
  15. GRB 190519A: Swift/UVOT Upper Limits
  16. GRB 190519A: CALET Gamma-Ray Burst Monitor detection
  17. LIGO/Virgo S190519bj: Swift/BAT Counterpart Search
  18. LIGO/Virgo S190519bj: MAXI/GSC Observations
  19. GRB 190519A: Swift-XRT refined Analysis
  20. LIGO/Virgo S190519bj Global MASTER-Net observations report
  21. GRB 190519A: Swift-BAT refined analysis
  22. LIGO/Virgo S190519bj: Fermi GBM Observations
  23. LIGO/Virgo S190519bj: HAWC follow-up
  24. GRB 190519A: Fermi GBM observation
  25. GRB 190519A: Swift detection of a burst
  26. GRB 190519A: Fermi GBM Final Real-time Localization
  27. LIGO/Virgo S190517h: CALET Observations
  28. LIGO/Virgo S190426c: NICER X-ray Follow-Up of ZTF19aassfws
  29. LIGO/Virgo S190518bb: Retraction of GW compact binary merger candidate
  30. LIGO/Virgo S190518bb Global MASTER-Net observations report
  31. Fermi GRB190517.81 Global MASTER-Net observations report
  32. GRB 190511A: Swift/UVOT further analysis
  33. Fermi Trigger 579814215 / GRB 190517813 / GRB190517A: BALROG localization
  34. GRB 190517A: Fermi GBM Final Real-time Localization
  35. LIGO/Virgo S190517h: Fermi-LAT search for a high-energy gamma-ray counterpart
  36. LIGO/Virgo S190517h: Swift/BAT Counterpart Search
  37. LIGO/Virgo S190517h: Insight-HXMT/HE observations
  38. LIGO/Virgo S190517h: Fermi GBM Observations
  39. LIGO/Virgo S190517h: HAWC follow-up
  40. LIGO/Virgo S190517h: MAXI/GSC Observations
  41. LIGO/Virgo S190517h Global MASTER-Net observations report
  42. GRB 190515A: CALET Gamma-Ray Burst Monitor detection
  43. LIGO/Virgo S190517h: IceCube Neutrino Search
  44. Fermi GRB190517.1 Global MASTER-Net observations report
  45. GRB 190515B: Swift/UVOT Upper Limits
  46. GRB 190515B: BOOTES-4/MET and 2.2m CAHA optical limits
  47. Fermi GRB190515.49 Global MASTER-Net observations report
  48. GRB 190515B: Swift-BAT refined analysis
  49. GRB 190515A: Insight-HXMT/HE detection
  50. GRB 190515A: Fermi GBM detection
  51. GRB 190515B: Swift-XRT refined Analysis
  52. GRB 190515A: Fermi-LAT detection
  53. Fermi GRB190515.43 Global MASTER-Net observations report
  54. Correction to GRB name for Swift trigger 903845
  55. GRB 190515B: Swift detection of a burst
  56. GRB 190510A: CALET Gamma-Ray Burst Monitor detection
  57. GRB 190515A: Fermi GBM Final Real-time Localization
  58. LIGO/Virgo S190513bm : TAROT-Calern and TAROT-Chile (TCA/TCH)/GRANDMA observation report.
  59. LIGO/Virgo S190513bm: CALET Observations
  60. Fermi GRB190514.67 Global MASTER-Net observations report
  61. LIGO/Virgo S190513bm: Lick/KAIT Follow-Up Observations
  62. LIGO/Virgo S190513bm: Swift/BAT Counterpart Search
  63. LIGO/Virgo S190513bm: Insight-HXMT/HE observation
  64. LIGO/Virgo S190510g: Swift-XRT observations and results
  65. LIGO/Virgo S190513bm: Fermi GBM Observations
  66. Konus-Wind observation of GRB 190510A
  67. LIGO/Virgo S190513bm: Fermi-LAT search for a high-energy gamma-ray counterpart
  68. LIGO/Virgo S190512at: CALET Observations
  69. LIGO/Virgo S190513bm: MAXI/GSC Observations
  70. LIGO/Virgo S190513bm Global MASTER-Net observations report
  71. LIGO/Virgo S190513bm: HAWC follow-up
  72. LIGO/Virgo S190512at: Insight-HXMT/HE observation
  73. GRB 190512A: Swift-BAT refined analysis
  74. LIGO/Virgo S190512at: Swift/BAT Counterpart Search
  75. LIGO/Virgo S190510g: Pan-STARRS and ATLAS observations and candidates
  76. LIGO/Virgo S190512at: Fermi-LAT search for a high-energy gamma-ray counterpart
  77. LIGO/Virgo S190512at: MAXI/GSC Observations
  78. LIGO/Virgo S190512at: Fermi GBM Observations
  79. LIGO/Virgo S190512at Global MASTER-Net observations report
  80. GRB 190512A: Fermi GBM observation
  81. LIGO/Virgo S190510g: MASTER OT detection inside PGC087378 galaxy
  82. LIGO/Virgo S190512at: INTEGRAL inactive at the time of the event
  83. Fermi GRB190512.62 Global MASTER-Net observations report
  84. Fermi GRB190512.61 Global MASTER-Net observations report
  85. GRB 190512A: Swift detection of a burst
  86. GRB 190512A: Fermi GBM Final Real-time Localization
  87. GRB 190511A: Swift-XRT refined Analysis
  88. IPN triangulation of GRB 190510A (short)
  89. LIGO/Virgo S190510g: CALET Observations
  90. GRB 190511A: Swift/UVOT Detection
  91. GRB 190511A: NOT optical afterglow
  92. LIGO/Virgo S190510g: GRAWITA REM and Loiano optical observations
  93. LIGO/Virgo S190510g: GRAWITA VST-ESO PARANAL optical observations
  94. GRB 190511A: Fermi-LAT detection
  95. GRB 190511A: Fermi GBM observation
  96. LIGO/Virgo S190510g: Pierre Auger Observatory follow-up
  97. GRB 190511A: Swift detection of a burst
  98. GRB 190511A: Fermi GBM Final Real-time Localization
  99. LIGO/Virgo S190510g: Insight-HXMT/HE updated observation
  100. LIGO/Virgo S190510g: Lick/KAIT Follow-Up Observations

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