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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"

5553 results found.

  1. LIGO/Virgo S230522a: Global MASTER-Net observations report
  2. LIGO/Virgo S230521k: Global MASTER-Net observations report
  3. Fermi Gamma-ray Burst Monitor trigger 706338208/230521211 is not a GRB
  4. LIGO/Virgo S230520ae: Global MASTER-Net observations report
  5. Fermi trigger No 706331483: Global MASTER-Net observations report
  6. Fermi trigger No 706317104: Global MASTER-Net observations report
  7. GRB 230520A: CALET Gamma-Ray Burst Monitor detection
  8. GRB 230521A: Fermi GBM Final Real-time Localization
  9. LIGO/Virgo/KAGRA S230518h: ATCA follow-up of candidate counterparts
  10. LIGO/Virgo/KAGRA S230518h: GECKO tiling observations with KMTNet
  11. GRB 230520A: MAXI/GSC detection
  12. LIGO/Virgo/Kagra S230518h: NED Galaxies in the Localization Volume
  13. LIGO/Virgo S230518h: Global MASTER-Net observations report
  14. GRB 230513A: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 705709044)
  15. GRB 230512A: Liverpool Telescope observations
  16. Fermi-LAT gamma-ray observations of IceCube-230511A
  17. GRB 230510A: OHP/T193 and OHP/T120 optical observations
  18. IceCube-230511A: Upper limits from a search for additional neutrino events in IceCube
  19. GRB 230510A: LCOGT Optical Upper Limit
  20. IceCube-230511A: IceCube observation of a high-energy neutrino candidate
  21. GRB 230511C: Fermi GBM Final Localization
  22. GRB 230510B: MAXI/GSC detection
  23. Fermi trigger No 705413051: Global MASTER-Net observations report
  24. Fermi Gamma-ray Burst Monitor trigger 230510133/705381054 is not a GRB
  25. GRB 230506C: NUTTelA-TAO / BSTI Early Optical Limits
  26. Fermi trigger No 704365743: Global MASTER-Net observations report
  27. GRB 230420A: BOOTES-5/JGT optical afterglow detection
  28. GRB 230307A: iTelescope optical upper limit (likely)
  29. GRB 230409B: OHP/T193 optical upper limit
  30. Fermi GRB 230409C: Global MASTER-Net observations report
  31. GRB 230405B: AGILE detection
  32. GRB 230405B: Fermi GBM Observation
  33. IceCube Alert 230405.56: Global MASTER-Net observations report
  34. GRB 230405B: Swift detection of a burst
  35. GRB 230405B: Fermi GBM Final Real-time Localization
  36. GRB 230405A: Fermi GBM Final Real-time Localization
  37. IceCube-230401A: Upper limits from a search for additional neutrino events in IceCube
  38. GRB 230328B: Multa observatory optical afterglow observation
  39. IceCube-Cascade 230329A: Upper limits from a search for additional neutrino events in IceCube
  40. GRB 230328B: 3.6m DOT multiband optical observation
  41. Fermi trigger No 701883729: Global MASTER-Net observations report
  42. GRB 230328B: GRBAlpha detection
  43. GRB 230328B: Nanshan/NEXT 2nd optical observation
  44. GRB 230328B NUTTelA-TAO / BSTI Early Measurements
  45. GRB 230328B: Liverpool Telescope afterglow detection
  46. GRB 230328B: GIT optical follow-up
  47. GRB 230328B: Nanshan/NEXT optical upper limit
  48. GRB 230328B: AstroSat CZTI detection
  49. GRB 230328B: Mondy, AbAO and Kitab optical observations
  50. GRB 230328B: Mondy optical afterglow confirmation
  51. Fermi GRB 230328A: Global MASTER-Net observations report
  52. GRB 230325A: Swift-BAT refined analysis
  53. GRB 230325A: Swift detection of a burst
  54. Fermi trigger No 701313046: Global MASTER-Net observations report
  55. Fermi trigger No 701321709: Global MASTER-Net observations report
  56. Swift GRB 230322B: Global MASTER-Net observations report
  57. GRB 230320B: GRBAlpha detection
  58. Fermi trigger No 701071944: Global MASTER-Net observations report
  59. GRB 230320B: Swift/BAT-GUANO detection outside the coded FOV
  60. Fermi GRB 230320A: Global MASTER-Net observations report
  61. Fermi GRB 230321A: Global MASTER-Net observations report
  62. Fermi trigger No 701058254: Global MASTER-Net observations report
  63. GRB 230321B: AstroSat CZTI detection
  64. GRB 230320B: AstroSat CZTI detection
  65. GRB 230314A: TURBO Optical Upper Limit
  66. Trigger 1160641: Swift detection of 4U 1630-472 (a.k.a. SWIFT J1633.8-4724A)
  67. Fermi trigger No 700976129: Global MASTER-Net observations report
  68. Fermi GRB 230316A: Global MASTER-Net observations report
  69. GRB 230304D: AstroSat CZTI detection
  70. IPN triangulation of GRB 230304B
  71. GRB 230313A: AstroSat CZTI detection
  72. GRB 230307A: Far off-axis NuSTAR detection of the GRB
  73. Fermi GRB 230314A: Global MASTER-Net observations report
  74. GRB 230307A: ATCA radio detection
  75. VZLUSAT-2 detection of SGR 1806-20
  76. GRB 230307A: INTEGRAL upper limit on Hard X-ray afterglow
  77. AMON Coincidence Alert from the sub-threshold IceCube-HAWC search NuEm-230313A
  78. Fermi GRB 230313A: Global MASTER-Net observations report
  79. GRB 230307A: soft X-ray detection with LEIA
  80. GRB 230309A: AstroSat CZTI detection of a bright long GRB
  81. Swift GRB230311.85: Global MASTER-Net observations report
  82. Swift GRB230311.83: Global MASTER-Net observations report
  83. Further improved IPN localization for GRB 230307A
  84. Swift GRB230311.81: Global MASTER-Net observations report
  85. GRB 230307A: SOAR/Goodman detection of the possible host galaxy
  86. Swift GRB230311.84: Global MASTER-Net observations report
  87. Swift GRB230311.82: Global MASTER-Net observations report
  88. TESS Detection of the Optical Afterglow of GRB230307A
  89. GRB 230310A: AstroSat CZTI detection
  90. GRB 230307A: GECKO optical observations and detections of the afterglow
  91. GRB 230307A: MAXI/GSC upper limit
  92. GRB 230307A: Gemini-South Confirmation of the Optical Afterglow
  93. Fermi GRB 230310A: Global MASTER-Net observations report
  94. GRB 230307A: AGILE/MCAL analysis
  95. GRB 230307A: ATLAS information on the ULTRACAM optical afterglow candidate
  96. GRB 230307A: Possible optical afterglow
  97. GRB 230307A: ASO-S/HXI detection
  98. GRB 230228A: NUTTelA-TAO / BSTI Optical Limits
  99. GRB 230308A: AGILE/MCAL detection
  100. GRB 230307A: Upper limits from a neutrino search with IceCube

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