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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"

5559 results found.

  1. GRB 190804B: Swift-XRT afterglow detection
  2. GRB 190805B: MAXI/GSC detection
  3. MAXI GRB190804.33 Global MASTER-Net observations report
  4. Fermi trigger No 586574612 Global MASTER-Net observations report
  5. GRB 190731A: no OT detected by MASTER
  6. LIGO/Virgo S190728q: AT2019lzt 10.4m GTC spectroscopy
  7. Fermi trigger No 586305505 Global MASTER-Net observations report
  8. LIGO/Virgo S190728q: No counterpart candidates in H.E.S.S. observations
  9. LIGO/Virgo S190728q: ZTF Forced Photometry for PS1 and DECam-GROWTH optical candidates, and a note on DECam Photometry from GCN 25215
  10. LIGO/Virgo S190727h: AstroSat CZTI upper limits
  11. LIGO/Virgo S190728q: Optical transients from Pan-STARRS coverage during first 2 nights
  12. LIGO/Virgo S190728q: GRAWITA VST-ESO PARANAL observations
  13. LIGO/Virgo S190728q: No counterpart candidates in KAIT observations
  14. LIGO/Virgo S190727h: No transient candidates in CALET observations
  15. LIGO/Virgo S190727h: No counterpart candidates in KAIT observations
  16. GRB 190727B: Swift detection of a burst
  17. LIGO/Virgo S190727h: No counterpart candidates in the Swift/BAT Observations
  18. LIGO/Virgo S190727h: No counterpart candidates in Fermi-LAT observations
  19. LIGO/Virgo S190727h: possible counterpart candidate in SPI-ACS/INTEGRAL
  20. LIGO/Virgo S190727h : no neutrino counterpart candidate in ANTARES search
  21. LIGO/Virgo S190727h: No counterpart candidates in AGILE-MCAL observations
  22. LIGO/Virgo S190727h: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  23. LIGO/Virgo S190727h: Coverage and upper limits from MAXI/GSC observations
  24. LIGO/Virgo S190727h: Identification of a GW compact binary merger candidate
  25. Fermi trigger No 585864875 Global MASTER-Net observations report
  26. LIGO/Virgo S190720a: No counterpart candidates in KAIT observations
  27. LIGO/Virgo S190718y: No counterpart candidates in CNEOST
  28. LIGO/Virgo S190718y: No counterpart candidates in KAIT observations
  29. GRB 190719B: a long GRB detected by INTEGRAL
  30. LIGO/Virgo S190718y : no neutrino counterpart candidate in ANTARES search
  31. LIGO/Virgo S190718y Global MASTER-Net observations report
  32. Fermi trigger No 585007213 Global MASTER-Net observations report
  33. Fermi trigger No 584929684 Global MASTER-Net observations report
  34. Fermi trigger No 584804684 Global MASTER-Net observations report
  35. GRB 190706D: Insight-HXMT/HE detection
  36. Fermi trigger No 584583925 Global MASTER-Net observations report
  37. Fermi trigger No 584465880 Global MASTER-Net observations report
  38. Fermi trigger No 584404689 Global MASTER-Net observations report
  39. Konus-Wind observation of GRB 190706D
  40. IPN triangulation of GRB 190706D (short)
  41. Fermi trigger No 584264100 Global MASTER-Net observations report
  42. LIGO/Virgo S190706ai: No counterpart candidates in KAIT observations
  43. IPN triangulation of GRB 190704A (short)
  44. LIGO/Virgo S190707q Global MASTER-Net observations report
  45. LIGO/Virgo S190707q : No neutrino counterpart candidates in ANTARES search
  46. LIGO/Virgo S190706ai: No neutrino counterpart candidates in ANTARES search
  47. IceCube-190704A - HAWC follow-up
  48. GRB 190706A: MAXI/GSC detection
  49. Fermi trigger No 584007338 Global MASTER-Net observations report
  50. IceCube-190704A: Upper limits from a search for additional neutrino events in IceCube
  51. Baksan Neutrino Observatory Alert 190703.56 Global MASTER-Net observations report
  52. Fermi trigger No 583854113 Global MASTER-Net observations report
  53. LIGO/Virgo S190630ag: no counterpart candidate in the SVOM/GWAC observations
  54. LIGO/Virgo S190701ah: KMTNet Observation
  55. GRB 190630C: ISON-Castelgrande optical upper limit
  56. GRB 190701A: COATLI Optical Observations
  57. GRB 190630C: Swift detection of a burst
  58. LIGO/Virgo S190630ag: No neutrino counterpart candidates in ANTARES search
  59. Fermi trigger No 583567803 Global MASTER-Net observations report
  60. Swift Trigger 912102: possible GRB 190630B
  61. GRB 190627A: Montarrenti Observatory optical detection
  62. Fermi trigger No 583221986 Global MASTER-Net observations report
  63. Fermi trigger No 583111521 Global MASTER-Net observations report
  64. GRB 190623A: Fermi GBM Final Real-time Localization
  65. Fermi trigger No 582886211 Global MASTER-Net observations report
  66. Fermi trigger No 582615488 Global MASTER-Net observations report
  67. Fermi trigger No 582304592 Global MASTER-Net observations report
  68. Fermi trigger No 582159815 Global MASTER-Net observations report
  69. GRB 190610A: Swift-XRT observations
  70. Fermi trigger No 582115625 Global MASTER-Net observations report
  71. IPN Triangulation of GRB 190611B
  72. GRB 190612A: Fermi GBM Final Real-time Localization
  73. Fermi trigger No 581882394 Global MASTER-Net observations report
  74. Fermi trigger No 581469752 Global MASTER-Net observations report
  75. GRB190604B: GROWTH-India telescope followup - no optical counterpart found
  76. S190602aq: MASTER OT detection
  77. Fermi trigger No 581281470 Global MASTER-Net observations report
  78. GRB 190530A: COATLI Optical Detection of the Fading Afterglow
  79. LIGO/Virgo S190425z: No counterpart candidate in Zadko-GRANDMA observations.
  80. LIGO/Virgo S190521g: AstroSat CZTI upper limits
  81. LIGO/Virgo S190521r: No optical counterpart from SVOM/GWAC-F30 observations.
  82. LIGO/Virgo S190521g: No optical counterpart from SVOM/GWAC-F30 observations.
  83. LIGO/Virgo S190521g: No optical counterpart from SVOM/GWAC observations.
  84. LIGO/Virgo S190521g: Upper limits from CALET observations
  85. LIGO/Virgo S190521g: No candidate counterpart in Fermi-LAT observations
  86. LIGO/Virgo S190517h : No counterpart candidate in TAROT-GRANDMA observations.
  87. LIGO/Virgo S190521g: No neutrino counterpart candidates in ANTARES search
  88. LIGO-Virgo S190521g: Upper Limits from AGILE-GRID observations
  89. IGO/Virgo S190521g: Coverage and upper limits from MAXI/GSC observations
  90. LIGO/Virgo S190521g: No counterpart candidates in INTEGRAL SPI/ACS & IBIS/PICsIT prompt observations
  91. LIGO/Virgo S190521g: No counterpart candidates in AGILE-MCAL observations
  92. LIGO/Virgo S190521g: Identification of a GW compact binary merger candidate
  93. LIGO/Virgo S190521g: INTEGRAL SPI/ACS prompt observation
  94. LIGO/Virgo S190521g Global MASTER-Net observations report
  95. LIGO/Virgo S190521g: IceCube Neutrino Search
  96. LIGO/Virgo S190512at: SVOM/GWAC-F60A observations
  97. LIGO/Virgo S190519bj Global MASTER-Net observations report
  98. LIGO/Virgo S190517h Global MASTER-Net observations report
  99. Fermi GRB190517.1 Global MASTER-Net observations report
  100. LIGO/Virgo S190513bm: Swope follow-up observations

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