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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"

5176 results found.

  1. GRB 191220A: Swift-XRT refined Analysis
  2. LIGO/Virgo S191220af: Global MASTER-Net observations report
  3. Konus-Wind observation of GRB 191218A
  4. LIGO/Virgo S191216ap, Swift XRT observations: 16 X-ray sources in the HAWC error region search
  5. LIGO/Virgo S191213g: No counterpart candidate in the NOWT observations
  6. LIGO/Virgo S191216ap: No candidates found in CHES observations of HAWC error region
  7. LIGO/Virgo S191216ap: No significant counterpart candidates in SAGUARO observations
  8. LIGO/Virgo S191215w : No significant candidates in TAROT - FRAM - GRANDMA observations.
  9. LIGO/Virgo S191213g: LCOGT photometry of ZTF19acymaru/AT2019wnh
  10. LIGO/Virgo S191213g: Lulin Follow-up Observations of ZTF19acykzsk/AT2019wqj
  11. LIGO/Virgo S191213g: Candidates from the Zwicky Transient Facility
  12. LIGO/Virgo S191213g: No neutrino candidates at Pierre Auger Observatory
  13. LIGO/Virgo S191205ah : No significant candidates in FRAM - TAROT – GRANDMA observations
  14. LIGO/Virgo S191205ah: Not observable by CALET
  15. LIGO/Virgo S191205ah: No neutrino candidates at Pierre Auger Observatory
  16. LIGO/Virgo S191129u : No significant candidates in FRAM-TAROT-GRANDMA observations.
  17. LIGO/Virgo S191204r: No significant candidates in FRAM-TAROT-GRANDMA observations.
  18. LIGO/Virgo S191205ah: Upper limits from Fermi-GBM Observations
  19. LIGO/Virgo S191205ah: Global MASTER-Net observations report
  20. LIGO/Virgo S191205ah: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  21. IceCube Alert 191204.95: Global MASTER-Net observations report
  22. Fermi trigger No 596808579: Global MASTER-Net observations report
  23. GRB 191129A: Fermi GBM Final Real-time Localization
  24. IceCube-191122A: Not observable by Fermi-GBM
  25. Fermi trigger No 596387570: Global MASTER-Net observations report
  26. Baksan Neutrino Observatory Alert 191124.13: Global MASTER-Net observations report
  27. LIGO/Virgo S191124be: Global MASTER-Net observations report
  28. GRB 191123A: Swift-XRT refined Analysis
  29. GRB 191122A: Swift-XRT refined Analysis
  30. GRB 191122A: CHES Optical Observations
  31. GRB 191117A: Fermi GBM Final Real-time Localization
  32. GRB 191111B: Fermi GBM Final Real-time Localization
  33. LIGO/Virgo S191109d: No significant candidates in FRAM-TAROT-GRANDMA observations
  34. LIGO/Virgo S191105e: No significant candidates in FRAM-TAROT-GRANDMA observations
  35. GRB 191106A: Swift-XRT refined Analysis
  36. LIGO/Virgo S191105e: No counterpart candidates in HAWC observations
  37. GRB 191106A: Mondy optical upper limit
  38. Fermi trigger No 594557071: Global MASTER-Net observations report
  39. GRB 191031C: Swift-BAT refined analysis
  40. GRB 191031C: Swift-XRT refined Analysis
  41. GRB 191031D: Swift-XRT refined Analysis
  42. GRB 191031D: Swift detection of a short hard burst
  43. GRB 191028B: MASTER optical observation
  44. GRB 191023A: MASTER optical observation
  45. GRB 191024A: Afterglow Upper Limits with LCO
  46. GRB 191024A: Swift-XRT refined Analysis
  47. GRB191024A: MASTER optical observation
  48. GRB 191017B: Swift-XRT refined Analysis
  49. GRB 191016A: Swift/UVOT Detection
  50. GRB 191016A: COATLI Optical Observations and Detection of the Afterglow
  51. GRB 191011A: Swift-XRT refined Analysis
  52. Fermi trigger No 592211224: Global MASTER-Net observations report
  53. LIGO/Virgo S190930s: no counterpart candidate in the SVOM/GWAC observations
  54. GRB 191004A: Swift-XRT refined Analysis
  55. FACT follow-up of IceCube-191001A
  56. GRB 191001A: Fermi GBM observation
  57. LIGO/Virgo S190930t: No neutrino candidates at Pierre Auger Observatory
  58. LIGO/Virgo S190930s: No counterpart candidates in KAIT observations
  59. GRB 190926A: Swift-XRT refined Analysis
  60. LIGO/Virgo S190923y: No significant candidates in TAROT-GRANDMA observations
  61. LIGO/Virgo S190924h: No counterpart candidates in Fermi-LAT observations
  62. LIGO/Virgo S190924h: Not observable by CALET
  63. LIGO/Virgo S190923y: No neutrino candidates at Pierre Auger Observatory
  64. LIGO/Virgo S190924h: no counterpart candidates in AGILE-GRID observations
  65. LIGO/Virgo S190924h: No counterpart candidates in AGILE-MCAL observations
  66. LIGO/Virgo S190924h: No counterpart candidates in INTEGRAL SPI-ACS and IBIS prompt observation
  67. LIGO/Virgo S190924h : no neutrino counterpart candidate in ANTARES search
  68. LIGO/Virgo S190924h: Coverage and upper limits from MAXI/GSC observations
  69. LIGO/Virgo S190924h: Global MASTER-Net observations report
  70. LIGO/Virgo S190924h: Identification of a GW compact binary merger candidate
  71. LIGO/Virgo S190924h: Upper limits from IceCube neutrino searches
  72. Integral GRB190919.99: Global MASTER-Net observations report
  73. LIGO/Virgo S190915ak: No significant candidates in TAROT-GRANDMA observations
  74. LIGO/Virgo S190915ak: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  75. LIGO/Virgo S190910d : No significant candidates in TAROT-GRANDMA observations
  76. LIGO/Virgo S190814bv: No counterpart candidate after completion of GRAWITA VST-ESO PARANAL transient survey.
  77. LIGO/Virgo S190910d: No Counterparts in DDOTI/OAN Optical Observations
  78. LIGO/Virgo S190910d and S190910h: No counterpart candidates in KAIT observations
  79. LIGO/Virgo S190910d: No neutrino candidates at Pierre Auger Observatory
  80. LIGO/Virgo S190814bv: VLA/JAGWAR monitoring of the 50% containment region
  81. LIGO/Virgo S190901ap: Gaia Photometric Alerts transient candidates
  82. ZTF19abvizsw/AT2019pim, search for GRB in SPI-ACS/INTEGRAL data
  83. IPN triangulation of GRB 190906A (short)
  84. LIGO/Virgo S190901ap: Second Epoch Hobby-Eberly Telescope observations of ZTF19abvionh
  85. LIGO/Virgo S190814bv: GRAWITA VST-ESO PARANAL observations and independent transient candidates discovery.
  86. LIGO/Virgo S190901ap : No significant candidates in TAROT-GRANDMA
  87. LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
  88. LIGO/Virgo S190901ap: no counterpart candidate in the SVOM/GWAC observations
  89. LIGO/Virgo S190828l: no counterpart candidate in the SVOM/GWAC observations
  90. LIGO/Virgo S190828j: no counterpart candidate in the SVOM/GWAC observations
  91. Fermi trigger No 589060361 Global MASTER-Net observations report
  92. LIGO/Virgo S190828j : No significant candidates in TAROT-GRANDMA observations
  93. LIGO/Virgo S190828l: No significant candidates in TAROT-GRANDMA observations
  94. GRB 190829A: Swift-XRT refined Analysis
  95. LIGO/Virgo S190828j: No Counterparts in DDOTI/OAN Optical Observations
  96. LIGO/Virgo S190828l: No counterpart candidates in KAIT observations
  97. Fermi trigger No 588801358 Global MASTER-Net observations report
  98. LIGO/Virgo S190426c: Update on Probability of Terrestrial Origin
  99. GRB 190828B: Swift-XRT refined Analysis
  100. LIGO/Virgo S190828j: No counterpart candidates in KAIT observations

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