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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.

Advanced Search Examples (click to copy):

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

11528 results found.

  1. GRB 191019B: Fermi GBM Final Real-time Localization
  2. Fermi trigger No 593176520: Global MASTER-Net observations report
  3. FACT follow-up of ANTARES-Fermi 191011A
  4. Fermi trigger No 593045905: Global MASTER-Net observations report
  5. GRB 191017C: Fermi GBM Final Real-time Localization
  6. GRB 191017A: Fermi GBM Final Localization
  7. 191017A: BALROG localization (Fermi Trigger 592997024 / GRB 191017391)
  8. Fermi trigger No 592818648: Global MASTER-Net observations report
  9. ANTARES 191011A: AMON + ANTARES Identification of a High-Energy Neutrino + Fermi LAT Coincidence
  10. GRB 191009A: AstroSat CZTI detection
  11. GRB 191011A: Swift/UVOT Detection
  12. GRB 191011A: Fermi GBM observation
  13. GRB 19011A: Optical Afterglow Detection with LCO
  14. GRB 191009A: Insight-HXMT/HE detection
  15. GRB 191011A: BALROG localization (Fermi Trigger 592461363 / GRB 191011192)
  16. GRB 191011A: VLT X-shooter redshift from RRM Observations
  17. GRB 191011A: Fermi GBM Final Real-time Localization
  18. GRB 191009A: BALROG localization (Fermi Trigger 592297741 / GRB 191009298)
  19. GRB 191009A: Fermi GBM Final Real-time Localization
  20. Fermi trigger No 592211224: Global MASTER-Net observations report
  21. Fermi trigger No 592211224: Global MASTER-Net observations report
  22. GRB 191008A: Fermi GBM Final Real-time Localization
  23. Fermi/GBM observation of a bright burst from magnetar SGR 1935+2154
  24. GRB 191001A: Swift-XRT observations
  25. GRB 191001A: Fermi GBM observation
  26. GRB 190919A: AstroSat CZTI detection
  27. Fermi-LAT Gamma-ray Observations of IceCube-191001A
  28. IceCube-191001A: Not observable by Fermi-GBM
  29. IPN triangulation of GRB 191001A
  30. GRB 191001A: Swift ToO observations
  31. GRB 191001A: KAIT Optical Upper Limit
  32. GRB 191001A: RATIR Optical and NIR Observations
  33. IceCube-191001A - IceCube observation of a high-energy neutrino candidate event
  34. GRB 191001A: DDOTI Optical Counterpart Candidate
  35. LIGO/Virgo S190930t: No counterpart candidates in Fermi-LAT observations
  36. Fermi trigger No 591604915: Global MASTER-Net observations report
  37. LIGO/Virgo S190930s: No counterpart candidates in Fermi-LAT observations
  38. GRB 191001A: BALROG localization (Fermi Trigger 591604915 / GRB 191001279)
  39. GRB 191001A: Fermi GBM Final Real-time Localization
  40. LIGO/Virgo S190930t: Upper limits from Fermi-GBM Observations
  41. LIGO/Virgo S190930s: Upper limits from Fermi-GBM Observations
  42. GRB 190928A: Insight-HXMT/HE detection
  43. Fermi trigger No 591532362: Global MASTER-Net observations report
  44. GRB 190930A: Fermi GBM Final Real-time Localization
  45. IPN triangulation of GRB 190928A (long/bright)
  46. Fermi trigger No 591391412: Global MASTER-Net observations report
  47. Fermi trigger No 591321287: Global MASTER-Net observations report
  48. LIGO/Virgo S190924h: No counterpart candidates in Fermi-LAT observations
  49. LIGO/Virgo S190924h: Upper limits from Fermi-GBM Observations
  50. Fermi-LAT Gamma-ray Observations of IceCube-190922B
  51. LIGO/Virgo S190923y: No counterpart candidates in Fermi-LAT observations
  52. Fermi-LAT Gamma-ray Observations of IceCube-190922A
  53. LIGO/Virgo S190923y: Upper limits from Fermi-GBM Observations
  54. GRB 190923A: BALROG localization (Fermi Trigger 590942887 / GRB 190923617)
  55. GRB 190923A: Fermi GBM Final Real-time Localization
  56. Fermi trigger No 590899086: Global MASTER-Net observations report
  57. IceCube-190922B: Upper limits from Fermi-GBM Observations
  58. IceCube-190922A: Upper limits from Fermi-GBM Observations
  59. IceCube-190922B - IceCube observation of a high-energy neutrino candidate event
  60. IceCube-190922A - IceCube observation of a high-energy neutrino candidate event
  61. Fermi trigger No 590777160: Global MASTER-Net observations report
  62. GRB 190921A: Fermi GBM Final Real-time Localization
  63. GRB 190919B: LCO Optical Afterglow Detection
  64. Fermi trigger No 590621700: Global MASTER-Net observations report
  65. Fermi trigger No 590610007: Global MASTER-Net observations report
  66. GRB 190919A: Fermi GBM Final Real-time Localization
  67. HAWC-190916A: Upper limits from Fermi-GBM Observations
  68. GRB 190828B: AstroSat CZTI detection
  69. Fermi trigger No 590335819: Global MASTER-Net observations report
  70. LIGO/Virgo S190915ak: Upper limits from Fermi-GBM Observations
  71. LIGO/Virgo S190915ak: No counterpart candidates in Fermi-LAT observations
  72. GRB 190916A: Fermi GBM Final Real-time Localization
  73. GRB 190915A: Insight-HXMT/HE detection
  74. GRB190915A: MASTER optical observation of BALROG Fermi GRB localization
  75. GRB 190915A: BALROG localization (Fermi Trigger 590219102 / GRB 190915240)
  76. GRB 190915A: Fermi GBM Final Real-time Localization
  77. GRB 190914A: Fermi GBM Final Real-time Localization
  78. GRB 190828C: AstroSat CZTI detection
  79. Fermi trigger No 590038994: Global MASTER-Net observations report
  80. LIGO/Virgo S190910h: No counterpart candidates in Fermi-LAT observations
  81. GRB 190913A: Fermi GBM Final Real-time Localization
  82. Update to the Fermi GBM Localizations
  83. LIGO/Virgo S190910d: No counterpart candidates in Fermi-LAT observations
  84. LIGO/Virgo S190910h: Upper limits from Fermi-GBM Observations
  85. LIGO/Virgo S190910d: Upper limits from Fermi-GBM Observations
  86. GRB 190910A: Fermi GBM Final Real-time Localization
  87. GRB 190901A: AstroSat CZTI detection
  88. ZTF19abvizsw/AT2019pim, search for GRB in SPI-ACS/INTEGRAL data
  89. Fermi trigger No 589561732 Global MASTER-Net observations report
  90. GRB 190829A observations in CrAO, photometry of the SN
  91. Fermi trigger No 589487114 Global MASTER-Net observations report
  92. GRB 190906B: Fermi GBM Final Real-time Localization
  93. GRB 190829A: GTC confirmation of an associated Type Ic-BL Supernova
  94. GRB 190829A: ATCA cm-band detection
  95. Fermi trigger No 589419513 Global MASTER-Net observations report
  96. GRB 190905A: Fermi GBM Final Real-time Localization
  97. Fermi GBM GCN 25668 Retraction
  98. GRB190829A: Keck LRIS spectroscopic confirmation of the accompanying supernova
  99. IPN triangulation of GRB 190903A (short)
  100. Konus-Wind observation of GRB 190829A

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