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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

596 results found.

  1. Konus-Wind detection of GRB 210928A
  2. Swift GRB 210919A: Global MASTER-Net observations report
  3. Konus-Wind detection of GRB 210905A
  4. Integral GRB210829.17: Global MASTER-Net observations report
  5. Integral GRB210829.14: Global MASTER-Net observations report
  6. GRB 210807C: Fermi GBM detection
  7. Konus-Wind detection of GRB 210702A
  8. Fermi trigger No 646194855: Global MASTER-Net observations report
  9. Swift GRB210618.07: Global MASTER-Net observations report
  10. Swift Detection of probable new Swift SGR J1555.2-5402
  11. Fermi GRB 210528A: Global MASTER-Net observations report
  12. GRB 210521A: MAXI/GSC detection
  13. GRB 210514A: update on the BAT trigger time and burst duration
  14. Swift Trigger 1045571 is not a GRB
  15. GRB 210419A: Swift-BAT refined analysis
  16. GRB 210410A: Swift-XRT refined Analysis
  17. Fermi trigger No 639199407: Global MASTER-Net observations report
  18. GRB 210403A: Swift-BAT refined analysis
  19. GRB 210318B: Swift-BAT refined analysis
  20. GRB 210204A: AstroSat CZTI Detection
  21. Fermi GRB 210120A: Global MASTER-Net observations report
  22. Fermi trigger No 631602681: Global MASTER-Net observations report
  23. GRB 210104A: GWAC-F60A optical afterglow observations
  24. GRB 201223A: Swift/UVOT Detection
  25. Konus-Wind detection of GRB 201216C
  26. Trigger 1007266: Swift detection of 1A 0535+262
  27. Swift Trigger 1006917 is Be/X-ray binary pulsar 1A 0535+262
  28. IceCube Alert 201014.09: Global MASTER-Net observations report
  29. GRB 201004A: Fermi GBM Final Localization
  30. Fermi trigger No 622618714: Global MASTER-Net observations report
  31. IPN triangulation of GRB 200916B (short)
  32. GRB 200903A: Fermi GBM detection
  33. Swift Trigger 992444 is due to detector noise
  34. Swift Trigger 990358 is due to detector noise
  35. Swift Trigger 989458 is due to detector noise
  36. Fermi GRB 200723A: Global MASTER-Net observations report
  37. GRB 200630A: Swift-BAT refined analysis
  38. GRB 200529A: Swift-BAT refined analysis
  39. GRB 200528A: Swift-BAT refined analysis
  40. Konus-Wind detection of short/hard GRB 200521A
  41. GRB 200519A: Swift-BAT refined analysis
  42. SGR 1935+2154: AstroSat CZTI detection
  43. IceCube-200425A: No counterpart candidates in INTEGRAL SPI-ACS prompt observation
  44. GRB 200412B: continued AbAO, Mondy, TSHAO, Terskol optical observations
  45. GRB 200416A: Swift-BAT refined analysis
  46. Fermi trigger No 607537834: Global MASTER-Net observations report
  47. Fermi trigger No 606799116: Global MASTER-Net observations report
  48. Konus-Wind observation of GRB 200313A
  49. SGR Swift J1818.0-1607: Swift-BAT refined analysis
  50. GRB 200227A: Swift-BAT refined analysis
  51. Konus-Wind observation of GRB 200219C
  52. LIGO/Virgo S200219ac: no counterpart candidate in SVOM/GWAC-F30 observations
  53. LIGO/Virgo S200219ac: No counterpart candidates in KAIT observations
  54. Swift GRB200216.56: Global MASTER-Net observations report
  55. LIGO/Virgo S200208q: No counterpart candidates in KAIT observations
  56. GRB 200131A: Swift-XRT refined Analysis
  57. Fermi trigger No 600666048: Global MASTER-Net observations report
  58. LIGO/Virgo S200105ae: Global MASTER-Net observations report
  59. GRB 191227A: Swift-BAT refined analysis
  60. Swift Trigger 946234: further Swift analysis
  61. GRB 191221B: Swift detection of a burst and a very bright optical candidate
  62. LIGO/Virgo S191220af: Global MASTER-Net observations report
  63. Konus-Wind observation of GRB 191218A
  64. LIGO/Virgo S191216ap: Global MASTER-Net observations report
  65. LIGO/Virgo S191212q: Global MASTER-Net observations report
  66. Fermi trigger No 596808579: Global MASTER-Net observations report
  67. GRB 191106A: Swift-BAT refined analysis
  68. GRB 191031D: Swift-BAT refined analysis
  69. GRB 191031C: Swift-BAT refined analysis
  70. GRB 191031A: Swift-BAT refined analysis
  71. TESS Detection of the Optical Emission from the Possible Untriggered GRB Associated with ZTF19abvizsw
  72. Konus-Wind observation of GRB 191004B
  73. GRB 191004A: Swift-BAT refined analysis
  74. LIGO/Virgo S190930t: J-GEM follow-up observation for Swift J221951-484240
  75. LIGO/Virgo S190930s: No counterpart candidates in KAIT observations
  76. Update to the Fermi GBM Localizations
  77. LIGO/Virgo S190910h: Identification of a GW compact binary merger candidate
  78. LIGO/Virgo S190901ap: No counterpart candidates in KAIT observations
  79. LIGO/Virgo S190901ap : GRAWITA photometric observation of candidate ZTFabvizsw and GCN 25618 revision
  80. LIGO/Virgo S190901ap: Upper limits from CALET observations.
  81. LIGO/Virgo S190901ap: Upper limits from Insight-HXMT/HE observations
  82. LIGO/Virgo S190901ap: Upper limits from Fermi-GBM Observations
  83. LIGO/Virgo S190901ap: No counterpart candidates in INTEGRAL SPI-ACS,prompt observation
  84. LIGO/Virgo S190828j: No counterpart candidates in KAIT observations
  85. Integral GRB190828.78 Global MASTER-Net observations report
  86. LIGO/Virgo S190814bv: No candidates found in J-GEM follow-up observations
  87. LIGO/Virgo S190728q: Coverage and upper limits from MAXI/GSC observations
  88. LIGO/Virgo S190718y: No counterpart candidates in CNEOST
  89. Fermi trigger No 585007213 Global MASTER-Net observations report
  90. Fermi trigger No 584264100 Global MASTER-Net observations report
  91. LIGO/Virgo S190706ai: No counterpart candidates in KAIT observations
  92. Swift GRB190631. Global MASTER-Net observations report
  93. LIGO/Virgo S190521r: CNEOST follow-up observations
  94. Fermi GRB190520.6 Global MASTER-Net observations report
  95. LIGO/Virgo S190517h: CALET Observations
  96. LIGO/Virgo S190517h: INTEGRAL prompt observation
  97. LIGO/Virgo S190517h: INTEGRAL/SPI-ACS prompt observation
  98. LIGO/Virgo S190510g: J-GEM optical/NIR follow-up observations
  99. LIGO/Virgo S190412m: Further J-GEM optical/NIR observations
  100. GRB 190427A, Swift-BAT refined analysis

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