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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"

42666 results found.

  1. GRB 260515A: SVOM detection of a burst
  2. GRB 260510C: Glowbug gamma-ray detection
  3. IceCube-260504A: No Candidate Transients from the Zwicky Transient Facility
  4. EP260514a: GROWTH-India Telescope optical upper limit
  5. GRB 260511B: NOT optical observations
  6. Konus-Wind detection of GRB 260512A
  7. GRB 260510C: CALET Gamma-Ray Burst Monitor detection
  8. EP260514a: Global MASTER-Net observations report
  9. EP260514a: Einstein Probe detection of a fast X-ray transient
  10. EP260512a: LCO optical upper limits
  11. IPN triangulation of GRB 260512A
  12. GRB 260511B: Mephisto multi-band optical followup
  13. Fermi GRB 260514A: Global MASTER-Net observations report
  14. GRB 260512A: AstroSat CZTI detection
  15. The EP-WXT trigger 01709262077 is likely a flaring star
  16. EP260512a: EP-FXT follow-up observation
  17. EP260507a: Xinglong Schmidt optical counterpart detection
  18. GRB 260514A: Fermi GBM Final Real-time Localization
  19. EP260512a: Global MASTER-Net observations report
  20. Fermi GRB 260513A: Global MASTER-Net observations report
  21. Fermi GRB 260512A: Global MASTER-Net observations report
  22. GRB 260511B: further SAO RAS optical observations
  23. GRB 260513A: Fermi GBM Final Real-time Localization
  24. GRB 260509A: SVOM/VT optical observations
  25. Konus-Wind detection of GRB 260511B
  26. The EP-WXT trigger 01709262036 is likely a flaring star
  27. EP260512a: Einstein Probe detection of an X-ray transient
  28. GRB 260512A: NuSTAR detection of prompt emission
  29. GRB 260509A: Infrared J and Hs observations with MDM/MIRAGE
  30. GRB 260510C: Infrared J and Hs detections with MDM/MIRAGE
  31. EP260507a: Infrared J and Hs upper limits with MDM/MIRAGE
  32. GRB 260512A: Fermi GBM Final Real-time Localization
  33. GRB 260511A: Glowbug gamma-ray detection
  34. Konus-Wind detection of GRB 260511A
  35. MASS-Cube (GRID 2.0) detection of GRB 260511A
  36. MASS-Cube (GRID 2.0) detection of GRB 260507A
  37. GRB 260511B: SAO RAS optical observations
  38. GRB 260510D: Glowbug gamma-ray detection of a likely short burst
  39. GRB 260511B: FRAM-ORM optical detection
  40. GRB 260511A: EP-FXT follow-up observation
  41. GRB 260511B: EP-FXT follow-up observation
  42. GRB 260511B: LCO optical counterpart detection
  43. GRB260511B: MAO/AZT-22 optical observations
  44. GRB 260511A: SVOM/VT optical observations
  45. GRB 260511B: LCO optical observations
  46. GRB 260511B: OHP/T193 spectroscopic observations
  47. GRB 260511B: GOTO optical counterpart detection
  48. GRB 260511B: Xinglong 2.16m/BEFOSC redshift confirmation
  49. GRB 260511B: SVOM/VT optical observations
  50. GRB 260511B: SVOM/COLIBRÍ (FM-GFT) optical observations
  51. GRB 260510B: EP-FXT follow-up observation
  52. GRB 260511B: OSIRIS+/GTC redshift z=2.006
  53. GRB 260510C: Fermi GBM Observation
  54. GRB 260509A: SAO RAS optical observations
  55. GRB 260511A: REM near-infrared detection
  56. GRB 260511B: GROWTH-India Telescope optical observations
  57. GRB 260511B: AstroSat CZTI detection
  58. GRB 260506B: Glowbug gamma-ray detection
  59. GRB 260506A: Glowbug gamma-ray detection of a short burst
  60. GRB 260511B: J-band observations by the SYSU 80 cm infrared telescope
  61. GRB 260511B: NuSTAR detection of prompt emission
  62. GRB 260511A: NuSTAR detection of prompt emission
  63. GRB 260511B: Fermi GBM Detection
  64. GRB 260511C: Fermi GBM Final Real-time Localization
  65. GRB 260511B: SVOM/VT optical observation with VHF data
  66. GRB 260511B: TRT optical observation
  67. GRB 260510B: SVOM/ECLAIRs refined analysis
  68. GRB 260511B : MITSuME Akeno optical afterglow candidate detection
  69. GRB 260511A: Fermi GBM Detection
  70. GRB 260511B SVOM/C-GFT optical counterpart detection
  71. EP260509a: LCO optical upper limits
  72. GRB 260511A: UTGO H50 optical afterglow observation
  73. GRB 260510C: AstroSat CZTI detection
  74. GRB 260511B: SVOM detection of a burst
  75. GRB 260511B: Fermi GBM Final Real-time Localization
  76. GRB 260510C: EP-FXT follow-up observation
  77. GRB 260510C: SVOM/VT optical counterpart confirmation
  78. EP260509a: EP-FXT non-detection and upper limit
  79. GRB 260511A: SVOM/VT optical observation with VHF data
  80. Fermi GRB 260511A: Global MASTER-Net observations report
  81. GRB 260511A: KAIT optical afterglow observations
  82. GRB 260511A: LCO optical afterglow detection
  83. GRB 260511A: SVOM/COLIBRÍ (FM-GFT) optical counterpart
  84. GRB 260511A: TRT optical counterpart detection
  85. GRB 260511A: SVOM detection of a bright burst
  86. GRB 260510C: SVOM/COLIBRÍ (FM-GFT) optical counterpart candidate
  87. GRB 260511A: Fermi GBM Final Real-time Localization
  88. GRB 260510B: SVOM/VT optical upper limits
  89. GRB 260510C: SVOM/VT optical upper limits
  90. GRB 260510C: MAXI/GSC detection
  91. EP260509a: Global MASTER-Net observations report
  92. Fermi GBM Sub-Threshold Detection of GRB 260510B
  93. GRB 260510D: Fermi GBM Final Real-time Localization
  94. GRB 260510B: GOTO early upper limit
  95. GRB 260510C: SVOM detection of a burst
  96. GRB 260510C: Fermi GBM Final Real-time Localization
  97. GRB 260510A: GECAM-B observation
  98. GRB 260510B: LCO optical upper limits
  99. EP260509a: Einstein Probe detection of an X-ray transient
  100. GRB 260509A: Liverpool Telescope optical observations

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