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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

28044 results found.

  1. LIGO/Virgo S190728q: Update on Sky-Localization and Source-Classification
  2. LIGO/Virgo S190728q: Photometric Redshift and Stellar Mass Estimates for the Potential Host Galaxy of Optical Counterpart Candidate ZTF19abjethn
  3. LIGO/Virgo S190728q: No counterpart candidates in the Swift/BAT Observations
  4. LIGO/Virgo S190728q: Optical Candidate from the Zwicky Transient Facility ZTF19abjethn
  5. LIGO/Virgo S190728q: No counterpart candidates in Fermi-LAT observations
  6. LIGO/Virgo S190728q: Second update on neutrino search with IceCube
  7. LIGO/Virgo S190728q: Upper limits from Fermi-GBM Observations
  8. LIGO/Virgo S190728q: no counterpart candidates in AGILE-GRID observations
  9. LIGO/Virgo S190728q : no neutrino counterpart candidate in ANTARES search
  10. LIGO/Virgo S190728q: No counterpart candidates in AGILE-MCAL observations
  11. LIGO/Virgo S190728q: One neutrino candidate from IceCube search
  12. LIGO/Virgo S190728q: No counterpart candidates in HAWC observations
  13. LIGO/Virgo S190728q: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  14. LIGO/Virgo S190728q: SPI-ACS/INTEGRAL data analysis
  15. LIGO/Virgo S190728q: Coverage and upper limits from MAXI/GSC observations
  16. LIGO/Virgo S190728q: Identification of a GW compact binary merger candidate
  17. LIGO/Virgo S190728q: Upper limits from IceCube neutrino searches
  18. GRB 190727B: Fermi GBM observations
  19. GRB 190727B: BALROG localization (Fermi Trigger 585951481 / GRB 190727846)
  20. GRB 190727B: Swift detection of a burst
  21. GRB 190727A: BALROG localization (Fermi Trigger 585936117 / GRB 190727668)
  22. LIGO/Virgo S190727h: No counterpart candidates in the Swift/BAT Observations
  23. LIGO/Virgo S190727h: No counterpart candidates in Fermi-LAT observations
  24. LIGO/Virgo S190727h: Upper limits from Fermi-GBM Observations
  25. LIGO/Virgo S190727h: No counterpart candidates in HAWC observations
  26. LIGO/Virgo S190727h : no neutrino counterpart candidate in ANTARES search
  27. LIGO/Virgo S190727h: No counterpart candidates in AGILE-MCAL observations
  28. LIGO/Virgo S190727h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  29. LIGO/Virgo S190727h: Coverage and upper limits from MAXI/GSC observations
  30. LIGO/Virgo S190727h: Identification of a GW compact binary merger candidate
  31. LIGO/Virgo S190727h: Upper limits from IceCube neutrino searches
  32. GRB 190726B: BALROG localization (Fermi Trigger 585864875 / GRB 190726843)
  33. GRB 190726A: BALROG localization (Fermi Trigger 585847498 / GRB 190726642)
  34. LIGO/Virgo S190718y: Classification of AT 2019lqm / Gaia19dcs as a Type Ia Supernova
  35. LIGO/Virgo S190718y: Swift XRT observations, 45 X-ray sources
  36. GRB 190724A: Insight-HXMT/HE detection
  37. GRB 190723A: Insight-HXMT/HE detection
  38. LIGO/Virgo S190720a: Thacher Observatory follow-up observations
  39. GRB 190719C: optical afterglow confirmation
  40. LIGO/Virgo S190720a: Updated localization from LIGO and Virgo data
  41. GRB 190720B: Insight-HXMT/HE detection
  42. LIGO/Virgo S190720a: No counterpart candidates in CNEOST observations
  43. LIGO/Virgo S190720a: No counterpart candidates in Fermi-LAT observations
  44. GRB 190720A: Fermi GBM detection
  45. GRB 190719C: Fermi GBM detection
  46. GRB 190719C: Swift-BAT refined analysis
  47. GRB 190719C: Swift/UVOT Upper Limits
  48. LIGO/Virgo S190720a: No counterpart candidates in the Swift/BAT Observations
  49. GRB 190719C: Swift-XRT light-curve fit
  50. GRB 190719C: Swift-XRT refined Analysis
  51. GRB 190720A: BALROG localization (Fermi Trigger 585326534 / GRB 190720613)
  52. LIGO/Virgo S190720a: Upper limits from Fermi-GBM Observations
  53. LIGO/Virgo S190720a: Upper limits from AGILE-GRID observations
  54. LIGO/Virgo S190720a : no neutrino counterpart candidate in ANTARES search
  55. LIGO/Virgo S190720a: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  56. LIGO/Virgo S190720a: Coverage and upper limits from MAXI/GSC observations
  57. LIGO/Virgo S190718y: No counterpart candidates in CNEOST
  58. LIGO/Virgo S190720a: AGILE-MCAL observations
  59. LIGO/Virgo S190720a: Identification of a GW compact binary merger candidate
  60. LIGO/Virgo S190720a: No counterpart candidates in HAWC observations
  61. LIGO/Virgo S190720a: Upper limits from IceCube neutrino searches
  62. GRB 190719C: NOT candidate optical afterglow and host
  63. LIGO/Virgo S190718y: Analysis update
  64. GRB 190719C: Swift detection of a burst
  65. MASTER OT detection inside LIGO/Virgo S190718y error box
  66. LIGO/Virgo S190718y: Upper limits from Insight-HXMT/HE observations
  67. LIGO/Virgo S190718y: No counterpart candidates in Fermi-LAT observations
  68. GRB 190719B: a long GRB detected by INTEGRAL
  69. LIGO/Virgo S190718y: Coverage and upper limits from MAXI/GSC observations
  70. LIGO/Virgo S190718y: Upper limits from CALET observations
  71. GRB 190718A: Swift-BAT refined analysis
  72. LIGO/Virgo S190718y: No counterpart candidates in the Swift/BAT Observations
  73. LIGO/Virgo S190718y: Upper limits from Fermi-GBM Observations
  74. LIGO/Virgo S190630ag: Updated sky localization
  75. GRB 190718A: Swift-XRT refined Analysis
  76. LIGO/Virgo S190718y: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  77. LIGO/Virgo S190718y : no neutrino counterpart candidate in ANTARES search
  78. GRB 190718A: Swift/UVOT Upper Limits
  79. LIGO/Virgo S190718y: Identification of a GW compact binary merger candidate
  80. LIGO/Virgo S190718y: Upper limits from IceCube neutrino searches
  81. GRB 190718A: Enhanced Swift-XRT position
  82. GRB 190718A: Swift detection of a burst
  83. GRB 190716A: BALROG localization (Fermi Trigger 585007213 / GRB 190716917)
  84. GRB 190708B: confirmation of the X-ray afterglow
  85. IceCube-190712A: Upper limits from a search for additional neutrino events in IceCube
  86. GRB 190714A: MAXI/GSC detection
  87. IceCube-190712A : Upper limits from Insight-HXMT/HE observations
  88. Fermi-LAT Gamma-ray Observations of IceCube-190712A
  89. IceCube-190712A: No neutrino counterpart candidates in ANTARES search
  90. GRB 190706D: Insight-HXMT/HE detection
  91. GRB 190706C: Insight-HXMT/HE detection
  92. IceCube-190712A: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  93. GRB 190708B: Swift-XRT observations
  94. LIGO/Virgo S190706ai: Upper limits from Insight-HXMT/HE observations
  95. LIGO/Virgo S190706ai: Updated sky localization
  96. LIGO/Virgo S190707q: Updated sky localization
  97. LIGO/Virgo S190707q: No counterpart candidates in the CNEOST
  98. LIGO/Virgo S190707q: No counterpart candidates in the Swift/BAT Observations
  99. Konus-Wind observation of GRB 190708B
  100. MAXI GRB190708.83 Global MASTER-Net observations report

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