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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"

36194 results found.

  1. GRB 190731A: Swift-XRT afterglow detection
  2. IPN Triangulation of GRB 190731A
  3. GRB 190731A: Fermi GBM detection
  4. GRB 190726B: AstroSat CZTI detection
  5. GRB 190731A: CALET Gamma-Ray Burst Monitor detection
  6. GRB 190731A: Swift ToO observations
  7. GRB190731A: Fermi-LAT detection
  8. GRB 190731A: Fermi GBM Final Real-time Localization
  9. IceCube 190730A: one weakly associated counterpart candidates in INTEGRAL SPI-ACS, and IBIS prompt observation
  10. Fermi Gamma-ray Burst Monitor trigger 190729668/586108936 is not a GRB
  11. Konus-Wind observation of GRB 190727B
  12. LIGO/Virgo S190728q: ZTF19abjethn TShAO and NUTTelA-TAO optical observations / classification
  13. GRB 190727B: Swift-BAT refined analysis
  14. IPN triangulation of GRB 190728A (short)
  15. LIGO/Virgo S190728q: No counterpart candidates in the Swift/BAT Observations
  16. LIGO/Virgo S190728q: Upper limits from Fermi-GBM Observations
  17. LIGO/Virgo S190728q: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  18. LIGO/Virgo S190728q: SPI-ACS/INTEGRAL data analysis
  19. GRB 190727B: Fermi-LAT detection
  20. GRB 190728A: Fermi GBM Final Real-time Localization
  21. GRB 190727B: Fermi GBM observations
  22. GRB 190727B: BALROG localization (Fermi Trigger 585951481 / GRB 190727846)
  23. GRB 190727B: Fermi GBM Final Real-time Localization
  24. GRB 190727B: Swift detection of a burst
  25. GRB 190727A: BALROG localization (Fermi Trigger 585936117 / GRB 190727668)
  26. LIGO/Virgo S190727h: No counterpart candidates in the Swift/BAT Observations
  27. GRB 190727A: Fermi GBM Final Real-time Localization
  28. LIGO/Virgo S190727h: possible counterpart candidate in SPI-ACS/INTEGRAL
  29. LIGO/Virgo S190727h: Upper limits from Fermi-GBM Observations
  30. LIGO/Virgo S190727h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  31. GRB 190726B: BALROG localization (Fermi Trigger 585864875 / GRB 190726843)
  32. GRB 190726B: Fermi GBM Final Real-time Localization
  33. GRB 190726A: BALROG localization (Fermi Trigger 585847498 / GRB 190726642)
  34. GRB 190726A: Fermi GBM Final Real-time Localization
  35. GRB 190724A: Insight-HXMT/HE detection
  36. GRB 190723A: Insight-HXMT/HE detection
  37. GRB 190720A: CALET Gamma-Ray Burst Monitor detection
  38. IPN triangulation of GRB 190724A (short)
  39. GRB 190719C: optical afterglow confirmation
  40. GRB 190724A: Fermi GBM Final Real-time Localization
  41. GRB 190723A: Fermi GBM Final Real-time Localization
  42. IPN triangulation of GRB 190720A
  43. GRB 190720B: Insight-HXMT/HE detection
  44. GRB 190720B: Fermi GBM Final Real-time Localization
  45. GRB 190720A: Fermi GBM detection
  46. GRB 190719C: Fermi GBM detection
  47. GRB 190719C: Swift-BAT refined analysis
  48. GRB 190719C: Swift/UVOT Upper Limits
  49. LIGO/Virgo S190720a: No counterpart candidates in the Swift/BAT Observations
  50. GRB 190719C: Swift-XRT light-curve fit
  51. GRB 190719C: Swift-XRT refined Analysis
  52. GRB 190720A: BALROG localization (Fermi Trigger 585326534 / GRB 190720613)
  53. GRB 190720A: Fermi GBM Final Real-time Localization
  54. LIGO/Virgo S190720a: Upper limits from Fermi-GBM Observations
  55. LIGO/Virgo S190720a: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  56. GRB 190719C: NOT candidate optical afterglow and host
  57. GRB 190719C: Swift detection of a burst
  58. GRB 190719C: Fermi GBM Final Real-time Localization
  59. LIGO/Virgo S190718y: Upper limits from Insight-HXMT/HE observations
  60. GRB 190719B: a long GRB detected by INTEGRAL
  61. GRB 190719A: Fermi GBM Final Real-time Localization
  62. GRB 190718A: Swift-BAT refined analysis
  63. LIGO/Virgo S190718y: Upper limits from Fermi-GBM Observations
  64. GRB 190718A: Swift-XRT refined Analysis
  65. LIGO/Virgo S190718y: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  66. GRB 190718A: Swift/UVOT Upper Limits
  67. GRB 190718A: FRAM-Auger optical limit
  68. GRB 190718A: Enhanced Swift-XRT position
  69. GRB 190718A: Swift detection of a burst
  70. GRB 190613B: FRAM-Auger afterglow detection
  71. GRB 190716A: BALROG localization (Fermi Trigger 585007213 / GRB 190716917)
  72. GRB 190716A: Fermi GBM Final Real-time Localization
  73. GRB 190714A: an X-ray flare from 2E 1624.6+1504/UCAC4 525-061488
  74. GRB 190708B: confirmation of the X-ray afterglow
  75. GRB 190714B: Fermi GBM Final Real-time Localization
  76. GRB 190714A: Tiled Swift observations
  77. GRB 190714A: MAXI/GSC detection
  78. IceCube-190712A : Upper limits from Insight-HXMT/HE observations
  79. IceCube-190712A: Upper limits from Fermi-GBM Observations
  80. GRB 190706D: Insight-HXMT/HE detection
  81. GRB 190706C: Insight-HXMT/HE detection
  82. IceCube-190712A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  83. GRB 190712A: Fermi GBM Final Real-time Localization
  84. GRB 190708B: Swift-XRT observations
  85. LIGO/Virgo S190706ai: Upper limits from Insight-HXMT/HE observations
  86. Konus-Wind observation of GRB 190706D
  87. LIGO/Virgo S190707q: No counterpart candidates in the Swift/BAT Observations
  88. Konus-Wind observation of GRB 190708B
  89. Konus-Wind observation of GRB 190706C
  90. GRB 190708B: Tiled Swift observations
  91. GRB 190706C: CALET Gamma-Ray Burst Monitor detection
  92. GRB 190708B: MAXI/GSC detection
  93. IPN triangulation of GRB 190706D (short)
  94. IPN triangulation of GRB 190706C (long/very bright)
  95. Konus-Wind observation of GRB 190704A
  96. GRB 190708A: Fermi GBM Final Real-time Localization
  97. LIGO/Virgo S190707q: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observations
  98. LIGO/Virgo S190707q: Upper limits from Fermi-GBM Observations
  99. LIGO/Virgo S190706ai: No counterpart candidates in the Swift/BAT Observations
  100. IPN triangulation of GRB 190704A (short)

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