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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"
  1. LIGO/Virgo S190706ai: Identification of a GW compact binary merger candidate
  2. LIGO/Virgo S190706ai: Upper limits from IceCube neutrino searches
  3. IceCube-190704A - HAWC follow-up
  4. GRB 190706B: Enhanced Swift-XRT position
  5. GRB 190706B: Prompt enhanced Swift-XRT position
  6. GRB 190706B: Swift detection of a burst
  7. GRB 190706A: MAXI/GSC detection
  8. Fermi trigger No 584007338 Global MASTER-Net observations report
  9. IceCube-190704A: Upper limits from Insight-HXMT/HE observations
  10. Fermi-LAT Gamma-ray Observations of IceCube-190704A and detection of the new gamma-ray source 1WHSP J104516.2+275133
  11. IceCube-190704A: Upper limits from a search for additional neutrino events in IceCube
  12. LIGO/Virgo S190701ah: Updated sky localization
  13. GRB 190627A: Discovery Channel Telescope late time observations
  14. LIGO/Virgo IceCube-190704A: No counterpart candidates in INTEGRAL SPI- ACS and IBIS prompt observation
  15. IceCube-190704A: not observable by Fermi-GBM
  16. Trigger 913042: Swift triggered on noise peak
  17. IceCube Alert 190704.78 Global MASTER-Net observations report
  18. IceCube-190704A - IceCube observation of a high-energy neutrino candidate event
  19. Baksan Neutrino Observatory Alert 190703.21 Global MASTER-Net observations report
  20. Konus-Wind observation of GRB 190701B
  21. GRB 190530A: Observation of the afterglow by NOEMA
  22. LIGO/Virgo S190630ag: Gaia Photometric Alerts transient candidate
  23. Baksan Neutrino Observatory Alert 190703.56 Global MASTER-Net observations report
  24. Fermi trigger No 583854113 Global MASTER-Net observations report
  25. LIGO/Virgo S190630ag: no counterpart candidate in the SVOM/GWAC observations
  26. GRB 190701A, Swift-BAT refined analysis
  27. GRB 190628B - AstroSat CZTI detection
  28. LIGO/Virgo S190701ah: KMTNet Observation
  29. LIGO/Virgo S190701ah: No transient candidates from CALET observations
  30. LIGO/Virgo S190701ah: Upper limits from Insight-HXMT/HE observations
  31. Fermi Gamma-ray Burst Monitor trigger 190626526/583245413 is not a GRB
  32. Fermi-LAT Gamma-ray Observations of IceCube-190629A
  33. LIGO/Virgo S190701ah: No counterpart candidates in the Swift/BAT Observations
  34. IPN triangulation of GRB 190630A (short)
  35. LIGO/Virgo S190701ah: Upper limits from AGILE-GRID observations
  36. LIGO/Virgo S190630ag: Upper limits from Insight-HXMT/HE observations
  37. LIGO/Virgo S190701ah: Upper limits from Fermi-GBM Observations
  38. GRB 190701A: Swift-XRT refined Analysis
  39. LIGO/Virgo S190630ag: Upper limits from CALET observations
  40. LIGO/Virgo S190701ah Global MASTER-Net observations report
  41. GRB 190630C: Swift-XRT refined Analysis
  42. LIGO/Virgo S190630ag: No counterpart candidates in KAIT observation
  43. LIGO/Virgo S190701ah: Coverage and upper limits from MAXI/GSC observations
  44. GRB 190701A: Swift/UVOT Upper Limits
  45. GRB190701A: No candidates/counterpart in optical follow-up from GROWTH-India Telescope
  46. LIGO/Virgo S190701ah: No counterpart candidates in AGILE-MCAL observations
  47. LIGO/Virgo S190701ah: No neutrino counterpart candidates in ANTARES search
  48. LIGO/Virgo S190701ah: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  49. LIGO/Virgo S190701ah: Identification of a GW compact binary merger candidate
  50. GRB 190630B: Tien Shan and Koshka Zeiss-1000 optical upper limits
  51. LIGO/Virgo S190701ah: Upper limits from IceCube neutrino searches
  52. GRB 190630C: ISON-Castelgrande optical upper limit
  53. GRB 190701A: COATLI Optical Observations
  54. GRB 190630C: Swift/UVOT Upper Limits
  55. GRB 190630C: KAIT Optical Upper Limit
  56. GRB 190630B: Swift/UVOT Upper Limits
  57. LIGO/Virgo S190630ag: No counterpart candidates in AGILE-GRID observations
  58. GRB 190630C: Swift-BAT refined analysis
  59. GRB 190701A: Enhanced Swift-XRT position
  60. GRB 190630C: AstroSat CZTI detection
  61. LIGO/Virgo S190630ag: No counterpart candidates in the Swift/BAT Observations
  62. GRB 190701A: MAXI/GSC detection
  63. GRB 190701B: a long GRB detected by IBAS
  64. GRB 190701A: Prompt enhanced Swift-XRT position
  65. GRB 190701A: Swift detection of a burst
  66. LIGO/Virgo S190630ag: No counterpart candidates in AGILE-MCAL observations
  67. LIGO/Virgo S190630ag: No counterpart candidates in Fermi-LAT observations
  68. GRB 190630B: KAIT Optical Afterglow Confirmation
  69. GRB 190630C: Enhanced Swift-XRT position
  70. Swift GRB190631. Global MASTER-Net observations report
  71. LIGO/Virgo S190630ag: Upper limits from Fermi-GBM Observations
  72. GRB 190630C: Swift detection of a burst
  73. LIGO/Virgo S190630ag: Coverage and upper limits from MAXI/GSC observations
  74. LIGO/Virgo S190630ag: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  75. LIGO/Virgo S190630ag: No neutrino counterpart candidates in ANTARES search
  76. LIGO/Virgo S190630ag: No counterpart candidates in HAWC observations
  77. LIGO/Virgo S190630ag: Identification of a GW compact binary merger candidate
  78. LIGO/Virgo S190630ag Global MASTER-Net observations report
  79. LIGO/Virgo S190630ag: Upper limits from IceCube neutrino searches
  80. GRB 190630B: Swift-XRT refined Analysis
  81. GRB 190630B, Swift-BAT refined analysis
  82. IceCube-190629A: Upper limits from Fermi-GBM Observations
  83. GRB 190627A: VLT/FORS2 spectroscopic redshift
  84. Fermi trigger No 583567803 Global MASTER-Net observations report
  85. GRB Swift Trigger 912102: KAIT Optical Afterglow Candidate
  86. Swift Trigger 912102: possible GRB 190630B
  87. GRB 190630A: Fermi GBM Final Real-time Localization
  88. GRB 190627A: Koshka Zeiss-1000 optical counterpart observations
  89. IceCube-190629A - IceCube observation of a high-energy neutrino candidate event
  90. Baksan Neutrino Observatory Alert 190629.56 Global MASTER-Net observations report
  91. IceCube Alert 190629.81 Global MASTER-Net observations report
  92. GRB 190627A : Xinglong 2.16m optical observation
  93. GRB 190627A: Swift-XRT refined Analysis
  94. GRB 190627A: GMG observation at the second epoch
  95. GRB 190627A: NOT optical observations
  96. GRB 190627A: Optical imaging by D50 from Ondrejov
  97. GRB 190627A: NIR imaging from Liverpool Telescope
  98. GRB 190627A: Optical imaging and spectroscopy from Calar Alto
  99. GRB 190627A: NUTTelA-TAO optical counterpart observations
  100. GRB 190627A: Swift-BAT refined analysis (short-soft burst)

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