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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"

12192 results found.

  1. GRB 200205B: Swift detection of a burst with optical counterpart
  2. Swift GRB200205.81: Global MASTER-Net observations report
  3. MeerKAT observation of GRB 191221B
  4. GRB 200205A: MAXI/GSC detection
  5. MAXI GRB200205.29: Global MASTER-Net observations report
  6. Re-classification of Fermi GBM triggers 200203137, 200203156/GRB200203A and 200203861
  7. LIGO/Virgo S200129m: Upper limits from Konus-Wind observations
  8. LIGO/Virgo S200128d: Upper limits from Konus-Wind observations
  9. Konus-Wind observation of GRB 200131A
  10. GRB 200131A: VIRT optical transient detection
  11. GRB 200201A: Fermi GBM Final Real-time Localization
  12. Swift GRB200131.95: Global MASTER-Net observations report
  13. Konus-Wind observation of GRB 200125B
  14. Konus-Wind observation of GRB 200130B
  15. IPN triangulation of GRB 200130B
  16. LIGO/Virgo S200128d: no counterpart candidate in SVOM/GWAC observations
  17. LIGO/Virgo S200128d : No significant candidates in FRAM - TAROT - GRANDMA observations
  18. LIGO/Virgo S200129m: NED Galaxies in the 50% Localization Volume
  19. LIGO/Virgo S200129m: No counterpart candidates in Fermi-LAT observations
  20. Konus-Wind observation of GRB 200125A
  21. LIGO/Virgo S200128d: upper limits from AGILE/GRID observations
  22. LIGO/Virgo S200129m: Coverage and upper limits from MAXI/GSC observations
  23. LIGO/Virgo S200128d: No counterpart candidates in Fermi-LAT observations
  24. LIGO/Virgo S200128d: Upper limits from CALET observations
  25. LIGO/Virgo S200128d: No counterpart candidates in KAIT observations
  26. LIGO/Virgo S200128d: no counterpart candidates in the Swift/BAT observations
  27. IPN triangulation of GRB 200125B
  28. Fermi-LAT-ANTARES coincidence
  29. LIGO/Virgo S200128d : no neutrino counterpart candidate in ANTARES search
  30. LIGO/Virgo S200128d: Coverage and upper limits from MAXI/GSC observations
  31. LIGO/Virgo S200128d: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  32. LIGO/Virgo S200128d: No counterpart candidates in HAWC observations
  33. LIGO/Virgo S200128d: Identification of a GW compact binary merger candidate
  34. Fermi trigger No 601841483: Global MASTER-Net observations report
  35. Swift GRB200127.61: Global MASTER-Net observations report
  36. GRB 200125B: Fermi GBM observations
  37. Fermi trigger No 601729856: Global MASTER-Net observations report
  38. Fermi trigger No 601677816: Global MASTER-Net observations report
  39. GRB 200125A: Swift-XRT refined Analysis
  40. GRB 200125B: BALROG localization (Fermi Trigger 601677816 / GRB 200125864)
  41. GRB 200125B: Fermi GBM Final Real-time Localization
  42. LIGO/Virgo S200114f : No significant candidates in TAROT - FRAM - GRANDMA observations
  43. IceCube-200120A: Event likely due to background
  44. GRB 200115A: Assy optical observations
  45. GRB 200122A: Mondy optical upper limit
  46. LIGO/Virgo S191222n: AstroSat CZTI upper limits
  47. LIGO/Virgo S200112r: AstroSat CZTI upper limits
  48. LIGO/Virgo S200114f: AstroSat CZTI upper limits
  49. Konus-Wind observation of GRB 200122A
  50. GRB 200122A: MITSuME Akeno optical upper limits
  51. LIGO/Virgo S200115j: Zwicky Transient Facility search for optical counterparts to Swift X-ray sources
  52. Fermi trigger No 601363105: Global MASTER-Net observations report
  53. Konus-Wind observation of GRB 200120A
  54. GRB 200122A: Swift-XRT refined Analysis
  55. GRB 200120A: AstroSat CZTI detection
  56. Fermi-LAT Gamma-ray Observations of IceCube-200120A
  57. LIGO/Virgo S200115j: Upper limits from Konus-Wind observations
  58. LIGO/Virgo S200114f: Upper limits from Konus-Wind observations
  59. LIGO/Virgo S200112r: Upper limits from Konus-Wind observations
  60. GRB 200122A: Swift detection of a burst
  61. IceCube-200120A: Upper limits from a search for additional neutrino events in IceCube
  62. IceCube-200120A: no counterpart candidates in INTEGRAL SPI-ACS and,IBIS prompt observation
  63. LIGO/Virgo S200105ae: Upper limits from Konus-Wind observations
  64. LIGO/Virgo S191222n: Upper limits from Konus-Wind observations
  65. LIGO/Virgo S191216ap: Upper limits from Konus-Wind observations
  66. LIGO/Virgo S191215w: Upper limits from Konus-Wind observations
  67. IceCube-200120A: IceCube observation of a high-energy neutrino candidate event
  68. GRB 200120A: Fermi GBM Final Real-time Localization
  69. IceCube Alert 200120.78: Global MASTER-Net observations report
  70. LIGO/Virgo S191213g: Upper limits from Konus-Wind observations
  71. LIGO/Virgo S191205ah: Upper limits from Konus-Wind observations
  72. LIGO/Virgo S191204r: Upper limits from Konus-Wind observations
  73. LIGO/Virgo S191129u: Upper limits from Konus-Wind observations
  74. Fermi-LAT Gamma-ray Observations of IceCube-200117A
  75. LIGO/Virgo S200115j : No significant candidates in TAROT - FRAM - GRANDMA observations
  76. LIGO/Virgo S200105ae: More candidates from the Zwicky Transient Facility
  77. IceCube-200117A: IceCube observation of a high-energy neutrino candidate event
  78. LIGO/Virgo S200115j: Swift-XRT sources
  79. LIGO/Virgo S200115j: Upper limits from CALET observations.
  80. LIGO/Virgo S200114f: ZTF Forced Photometry of the Swift Source S200114f_X2
  81. LIGO/Virgo S200112r : No significant candidates in TAROT - FRAM - GRANDMA observations.
  82. LIGO/Virgo S200114f: Swift-XRT sources and observations
  83. LIGO/Virgo S200115j: no counterpart candidate in SVOM/GWAC observations
  84. Baksan Neutrino Observatory Alert 200116.22: Global MASTER-Net observations report
  85. LIGO/Virgo S200115j: No counterpart candidates in Fermi-LAT observations
  86. LIGO/Virgo S200115j: Revised list of possible host galaxies with the new skymap
  87. LIGO/Virgo S200115j: Coverage and upper limits from MAXI/GSC observations
  88. LIGO/Virgo S200115j: No counterpart candidates in HAWC observations
  89. LIGO/Virgo trigger S200115j: Possible host galaxies
  90. LIGO/Virgo S200114f: Candidates from SAGUARO observations
  91. LIGO/Virgo S200114f: No Counterparts in DDOTI/OAN Optical Observations
  92. LIGO/Virgo S200114f: No counterpart candidates in Fermi-LAT observations
  93. LIGO/Virgo S200114f: Coverage and upper limits from MAXI/GSC observations
  94. Fermi trigger No 600666048: Global MASTER-Net observations report
  95. LIGO/Virgo S200114f: No counterpart candidates in HAWC observations
  96. Fermi-LAT Gamma-ray Observations of IceCube-200109A and detection of a possible new gamma-ray source, Fermi J1055.8+1034
  97. LIGO/Virgo 200112r: No counterpart candidates in Fermi-LAT observations
  98. LIGO/Virgo S200112r: Coverage and upper limits from MAXI/GSC observations
  99. LIGO/Virgo S200112r: No counterpart candidates in HAWC observations
  100. LIGO/Virgo S200112r: Global MASTER-Net observations report

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