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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"

39369 results found.

  1. ZTF23aaoohpy/AT2023lcr: Montarrenti Observatory optical observations
  2. ZTF23aaoohpy (AT2023lcr/ATLAS23msn): Upper limits from Konus-Wind observations
  3. LIGO/Virgo S230620ad: Global MASTER-Net observations report
  4. LIGO/Virgo S230620au: Global MASTER-Net observations report
  5. ZTF23aaoohpy/AT2023lc: Mondy optical observations
  6. IPN triangulation of GRB 230616A (short)
  7. LIGO/Virgo/KAGRA S230619bg: one counterpart neutrino candidate from IceCube neutrino searches
  8. AT2023lcr (ATLAS23msn/ZTF23aaoohpy): Kinder observations with Lulin observatory and a probable plateau in the g-band light curve
  9. ZTF23aaoohpy/AT2023lcr: Keck/LRIS spectroscopy and redshift
  10. ZTF23aaoohpy/AT2023lcr: Xinglong-2.16m optical observations
  11. LIGO/Virgo S230620al: Global MASTER-Net observations report
  12. LIGO/Virgo S230620af: Global MASTER-Net observations report
  13. LIGO/Virgo S230620z: Global MASTER-Net observations report
  14. LIGO/Virgo S230620w: Global MASTER-Net observations report
  15. LIGO/Virgo S230619bg: Global MASTER-Net observations report
  16. LIGO/Virgo S230620g: Global MASTER-Net observations report
  17. LIGO/Virgo S230619ay: Global MASTER-Net observations report
  18. ZTF23aaoohpy/AT2023lcr: Liverpool Telescope detection
  19. LIGO/Virgo S230619bd: Global MASTER-Net observations report
  20. LIGO/Virgo S230619bb: Global MASTER-Net observations report
  21. LIGO/Virgo S230619as: Global MASTER-Net observations report
  22. LIGO/Virgo S230619ap: Global MASTER-Net observations report
  23. ZTF23aaoohpy/AT2023lcr: GROWTH-India Telescope follow-up observations
  24. GRB 230618A: Osservatorio Astronomico Nastro verde upper limit
  25. ZTF23aaoohpy/AT2023lcr: Zwicky Transient Facility discovery of a fast fading red transient
  26. LIGO/Virgo S230619i: Global MASTER-Net observations report
  27. LIGO/Virgo S230619aa: Global MASTER-Net observations report
  28. LIGO/Virgo S230619x: Global MASTER-Net observations report
  29. LIGO/Virgo S230619e: Global MASTER-Net observations report
  30. LIGO/Virgo S230618at: Global MASTER-Net observations report
  31. LIGO/Virgo S230618ba: Global MASTER-Net observations report
  32. LIGO/Virgo S230618az: Global MASTER-Net observations report
  33. LIGO/Virgo S230618ae: Global MASTER-Net observations report
  34. LIGO/Virgo S230618aq: Global MASTER-Net observations report
  35. LIGO/Virgo S230618y: Global MASTER-Net observations report
  36. LIGO/Virgo S230618s: Global MASTER-Net observations report
  37. GRB 230618A: Enhanced Swift-XRT position
  38. GRB 230618A: Swift/UVOT Upper Limits
  39. GRB 230618A: Swift-XRT refined Analysis
  40. GRB 230616A: Swift-XRT observations
  41. LIGO/Virgo S230618r: Global MASTER-Net observations report
  42. LIGO/Virgo S230616aa: Global MASTER-Net observations report
  43. LIGO/Virgo S230615an: Global MASTER-Net observations report
  44. LIGO/Virgo S230615ak: Global MASTER-Net observations report
  45. GRB 230618A: KAIT Optical Observations
  46. LIGO/Virgo S230617ba: Global MASTER-Net observations report
  47. LIGO/Virgo S230618k: Global MASTER-Net observations report
  48. LIGO/Virgo S230618d: Global MASTER-Net observations report
  49. LIGO/Virgo S230617bc: Global MASTER-Net observations report
  50. LIGO/Virgo S230617aq: Global MASTER-Net observations report
  51. LIGO/Virgo S230617ab: Global MASTER-Net observations report
  52. Swift GRB 230618A: Global MASTER-Net observations report
  53. LIGO/Virgo S230617aj: Global MASTER-Net observations report
  54. GRB230618A: LCOGT Optical Observations
  55. GRB 230618B: Fermi GBM Final Real-time Localization
  56. GRB 230618A: Prompt enhanced Swift-XRT position
  57. GRB 230618A: Swift detection of a burst
  58. GRB 230616A: Swift ToO observations
  59. GRB 230617A: Fermi GBM Final Real-time Localization
  60. GRB 230614C: GRBAlpha detection
  61. GRB 230616A: AstroSat CZTI detection
  62. GRB 230616A: Swift/BAT-GUANO detection of a short burst outside the coded FOV
  63. LIGO/Virgo/KAGRA S230615az: Xinglong-2.16m photometric observations of GIT candidates
  64. LIGO/Virgo S230616s: Global MASTER-Net observations report
  65. LIGO/Virgo S230615be: Global MASTER-Net observations report
  66. LIGO/Virgo S230615af: Global MASTER-Net observations report
  67. LIGO/Virgo S230616j: Global MASTER-Net observations report
  68. LIGO/Virgo/KAGRA S230615az: GROWTH-India candidates
  69. LIGO/Virgo S230615av: Global MASTER-Net observations report
  70. LIGO/Virgo S230615az: Global MASTER-Net observations report
  71. LIGO/Virgo S230615ax: Global MASTER-Net observations report
  72. LIGO/Virgo S230615k: Global MASTER-Net observations report
  73. GRB 230614C: AstroSat CZTI detection
  74. LIGO/Virgo S230615t: Global MASTER-Net observations report
  75. GRB 230614B: Fermi GBM Observation
  76. GRB 230614C: Fermi GBM Detection
  77. LIGO/Virgo S230615i: Global MASTER-Net observations report
  78. LIGO/Virgo S230613at: Global MASTER-Net observations report
  79. LIGO/Virgo S230614ac: Global MASTER-Net observations report
  80. LIGO/Virgo S230614t: Global MASTER-Net observations report
  81. LIGO/Virgo S230614o: Global MASTER-Net observations report
  82. GRB 230614B: Swift/BAT-GUANO detection outside the coded FOV
  83. Fermi trigger No 708426906: Global MASTER-Net observations report
  84. GRB 230614B: Fermi GBM Final Real-time Localization
  85. GRB 230614A: Fermi GBM Final Real-time Localization
  86. GRB 230606A: LCOGT Optical Observations
  87. LIGO/Virgo S230611be: Global MASTER-Net observations report
  88. LIGO/Virgo S230611l: Global MASTER-Net observations report
  89. LIGO/Virgo S230609u: Global MASTER-Net observations report
  90. GRB 230608A: CALET Gamma-Ray Burst Monitor detection
  91. GRB 230608A: AstroSat CZTI detection
  92. GRB 230608A: AGILE detection
  93. LIGO/Virgo S230608aw: Global MASTER-Net observations report
  94. LIGO/Virgo S230608as: Global MASTER-Net observations report
  95. LIGO/Virgo S230609a: Global MASTER-Net observations report
  96. LIGO/Virgo S230608ah: Global MASTER-Net observations report
  97. LIGO/Virgo S230608q: Global MASTER-Net observations report
  98. ZTF23aamxeqf/AT2023jxk: 1.3m DFOT Optical upper limit
  99. Fermi GRB 230603A: Global MASTER-Net observations report
  100. Fermi trigger No 707039690: Global MASTER-Net observations report

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