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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"

11849 results found.

  1. GRB 191125B: MASTER-VWFC synchronous observation
  2. Fermi trigger No 596387570: Global MASTER-Net observations report
  3. Fermi-LAT Gamma-ray Observations of IceCube-191122A
  4. LIGO/Virgo S191124be: Global MASTER-Net observations report
  5. GRB 191123A: Swift-XRT refined Analysis
  6. GRB 191123A: Swift detection of a burst with an optical counterpart
  7. GRB 191122A: Swift-BAT refined analysis
  8. GRB 191122A: Swift-XRT refined Analysis
  9. IceCube-191119A: No significant detection in HAWC
  10. LIGO/Virgo S191120aj: Global MASTER-Net observations report
  11. IceCube-191119A: Upper limits from a search for additional neutrino events in IceCube
  12. Fermi-LAT Gamma-ray Observations of IceCube-191119A
  13. IceCube-191119A - No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  14. Swift Trigger 937114 is not an astrophysical source
  15. Swift GRB191115A: Global MASTER-Net observations report
  16. LIGO/Virgo S191110af: Upper limits from Konus-Wind observations
  17. Konus-Wind observation of the recent SGR 1935+2154 activity
  18. LIGO/Virgo S191110af: Swift XRT observations, no secure afterglow found
  19. LIGO/Virgo S191110af: Upper limits from IceCube MeV neutrino searches
  20. LIGO/Virgo S191110af: No counterpart candidates in Fermi-LAT observations
  21. LIGO/Virgo S191110af: Upper limits from Fermi-GBM Observations
  22. LIGO/Virgo S191110af: Coverage and upper limits from MAXI/GSC observations
  23. LIGO/Virgo S191109d: No significant candidates in FRAM-TAROT-GRANDMA observations
  24. LIGO/Virgo S191110x: Global MASTER-Net observations report
  25. LIGO/Virgo S191109d: No counterpart candidates in Fermi-LAT observations
  26. LIGO/Virgo S191105e: No significant candidates in FRAM-TAROT-GRANDMA observations
  27. LIGO/Virgo S191109d: AstroSat CZTI upper limits
  28. LIGO/Virgo S191109d: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  29. LIGO/Virgo S191109d: Coverage and upper limits from MAXI/GSC observations
  30. ZTF19abvizsw: Upper limits from Konus-Wind observations
  31. LIGO/Virgo S191105e: AstroSat CZTI upper limits
  32. LIGO/Virgo S191105e: No counterpart candidates in Fermi-LAT observations
  33. LIGO/Virgo S191105e: Coverage and upper limits from MAXI/GSC observations
  34. GRB 191106A: Swift-XRT refined Analysis
  35. LIGO/Virgo S191105e: No counterpart candidates in HAWC observations
  36. GRB 191106A: MASTER optical observation
  37. GRB 191106A: Swift detection of a burst
  38. Fermi trigger No 594592184: Global MASTER-Net observations report
  39. Swift GRB191105.01: Global MASTER-Net observations report
  40. GRB 191101A: Swift-BAT refined analysis
  41. Fermi GBM GRB 191104C (trigger 594592184 / 191104854) is not a GRB
  42. GRB 191104C: Fermi GBM Final Real-time Localization
  43. Fermi GBM GRBs 191104 A, B, C and triggers 594534420/191104185 and 594563923/191104527 are not GRBs
  44. Fermi trigger No 594563923: Global MASTER-Net observations report
  45. Fermi trigger No 594557071: Global MASTER-Net observations report
  46. Fermi GBM triggers 594523229/191104056 and 594528816/191104120 are not GRBs
  47. Konus-Wind observation of GRB 191031D: correction to GCN 26126
  48. GRB 191101A: Swift-XRT refined Analysis
  49. GRB 191101A: VIRT Optical Upper Limits
  50. Swift GRB191101.88: Global MASTER-Net observations report
  51. Fermi trigger No 594227699: Global MASTER-Net observations report
  52. GRB 191101A: Swift detection of a burst
  53. GRB 191031C: Swift-BAT refined analysis
  54. Konus-Wind observation of GRB 191031D
  55. GRB 191031D: Swift-XRT refined Analysis
  56. GRB 191031C: Fermi GBM detection
  57. GRB 191031C: Swift detection of a burst
  58. Konus-Wind observation of GRB 191027A
  59. GRB 191029A: CORRECTED Swift-XRT refined analysis
  60. GRB 191019A: Zadko Telescope optical observations
  61. GRB 191029A: Swift-XRT refined Analysis
  62. GRB 191028B: MASTER optical observation
  63. GRB 191029A: Swift-XRT observations
  64. Konus-Wind observation of GRB 191025B
  65. GRB 191029A: Swift detection of a burst
  66. GRB 191024A: Swift-XRT refined Analysis
  67. GRB191024A: MASTER optical observation
  68. GRB 191019A: Swift-XRT updated analysis
  69. Swift GRB191020.81: Global MASTER-Net OT detection
  70. GRB 191019A: Swift-BAT refined analysis
  71. GRB 191019A: GROND observations
  72. Fermi trigger No 593176520: Global MASTER-Net observations report
  73. Alert from the HAWC Burst Monitor HAWC-191019A
  74. FACT follow-up of ANTARES-Fermi 191011A
  75. GRB 191019A: Swift-XRT observations
  76. GRB 191017B: Swift-XRT refined Analysis
  77. GRB 191017C: Fermi GBM Final Real-time Localization
  78. GRB 191017B: Swift detection of a burst
  79. GRB 191016A: AZT-20 (Assy observatory) optical photometry
  80. Fermi trigger No 592818648: Global MASTER-Net observations report
  81. GRB 191011A: Swift-BAT refined analysis
  82. GRB 191011A: Swift-XRT refined Analysis
  83. Swift GRB191011.19: Global MASTER-Net observations report
  84. GRB 191011A: Swift detection of a burst with an optical counterpart
  85. TESS Detection of the Optical Emission from the Possible Untriggered GRB Associated with ZTF19abvizsw
  86. Konus-Wind observation of GRB 191004B
  87. Konus-Wind observation of GRB 191004A
  88. GRB 191004A: Optical Detection with LCO
  89. LIGO/Virgo S190930s: no counterpart candidate in the SVOM/GWAC observations
  90. LIGO/Virgo S190930t: Swift XRT observations, no secure afterglow found
  91. GRB 191004B: Swift-XRT refined Analysis
  92. GRB 191004A: Swift-XRT refined Analysis
  93. FACT follow-up of IceCube-191001A
  94. LIGO/Virgo S190930t: AT2019rpn, AT2019rpj CrAO continued optical photometry
  95. IceCube-191001A: HAWC follow-up
  96. GRB 190919A: AstroSat CZTI detection
  97. Fermi-LAT Gamma-ray Observations of IceCube-191001A
  98. LIGO/Virgo S190930t: AT2019rpn, AT2019rpj CrAO optical photometry
  99. LIGO/Virgo S190930t: Candidates from ATLAS observations and constraints on AT2019rpr and AT2019rpn
  100. GRB 191001A: RATIR Optical and NIR Observations

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