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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"

42261 results found.

  1. sb26021801: SVOM detection of a long faint X-ray transient
  2. The EP-WXT trigger 01709258455 is likely a flaring star
  3. EP-WXT 01709258455: NOT optical upper limits
  4. EP260214b: Mondy optical observations
  5. EP260214b: 1.3m DFOT optical upper limit
  6. EP260210a: Mondy optical upper limits
  7. Konus-Wind detection of GRB 260212A
  8. GRB 260208A: AbAO and Terskol optical upper limits
  9. GRB 260208A: continued Mondy optical observations
  10. IceCube-260217A - IceCube observation of a high-energy neutrino candidate track-like event
  11. GRB 260213A: GECAM-B observation of a short burst
  12. GRB 260216A: Fermi GBM Final Real-time Localization
  13. EP260214b: Liverpool Telescope optical observations
  14. GRB 260206A: probable hard X-ray burst from 4U 0513-40
  15. EP260214b: Optical upper limit with Kinder observations
  16. EP260214a: Optical upper limits with Kinder observations
  17. EP260214b: EP-FXT follow-up observation
  18. EP260214a / GRB 260214A: Fermi-GBM Sub-Threshold Detection
  19. EP260214b: DDOTI Optical Detection
  20. EP260214b: GROWTH-India Telescope optical upper limit
  21. EP260214a: VLT near-infrared observation
  22. EP260214b: SVOM/VT optical observation
  23. EP260214a: NOT optical upper limits
  24. EP260214a: COLIBRÍ optical upper limits
  25. EP260214b: OHP/T120 optical observations
  26. EP260214a: refined analysis of the EP-FXT observation
  27. EP260214b: LCO optical counterpart detection
  28. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  29. GRB 260211A: SVOM/VT optical counterpart
  30. EP260214b: COLIBRÍ optical observations
  31. EP260214a: SVOM/VT optical upper limits
  32. EP260214b: NOT optical counterpart detection
  33. EP260214b: Einstein Probe detection of a fast X-ray transient
  34. EP260214a: Global MASTER-Net observations report
  35. EP260214a: Einstein Probe detection of an X-ray transient
  36. GRB 260212A: AstroSat CZTI detection
  37. GRB 260212A: Fermi GBM Observation
  38. EP260213a: Liverpool Telescope optical upper limits
  39. EP260213a: Global MASTER-Net observations report
  40. EP260213a: COLIBRÍ optical upper limits
  41. GRB 260212A: GECAM-B observation
  42. EP260213a: Optical upper limits with Kinder observations
  43. EP260213a: SVOM/VT optical upper limit
  44. EP260213a: Mondy R-band optical upper limit
  45. EP260213a: NUTTelA-TAO Early Optical Limits
  46. EP260213a: SVOM/C-GFT upper limit
  47. EP260213a: refined analysis of the EP-FXT observation
  48. EP260213a: Einstein Probe detection of a fast X-ray transient
  49. EP/WXT 01709258378: NOT optical upper limits
  50. GRB 260212A: SVOM/GRM observation of a long burst
  51. GRB 260213B: Fermi GBM Final Localization
  52. GRB 260213B: BALROG localization (Fermi Trigger 792697214 / GRB 260213736)
  53. GRB 260211A - SVOM/ECLAIRs refined analysis
  54. GRB 260204A: SVOM/ECLAIRs refined analysis
  55. GRB 260213A: Fermi GBM Final Localization
  56. GRB 260211A: EP-FXT follow-up observation
  57. GRB 260211A: SVOM/VT optical observation
  58. GRB 260212A: Glowbug gamma-ray detection
  59. GRB 260211A: GOTO optical upper limit
  60. Fermi GRB 260212A: Global MASTER-Net observations report
  61. GRB 260212A: Fermi GBM Final Real-time Localization
  62. GRB 260211A: LAST optical upper limit
  63. GRB 260210A: SVOM/GRM observation
  64. Fermi GBM Sub-Threshold Detection of GRB 260211A
  65. Konus-Wind detection of GRB 260207B
  66. GRB 260128B: SVOM/ECLAIRs refined analysis
  67. GRID detection of GRB 260207B
  68. GRB 260211A: LCO optical upper limits
  69. GRB260131A/B: 3.6m DOT Optical Observations
  70. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  71. Fermi trigger No 792537871: Global MASTER-Net observations report
  72. GRB 260211A: SVOM detection of a burst
  73. Swift Operations Update + Community Forum (Friday, February 13 @ 10:00 AM EST)
  74. Konus-Wind detection of GRB 260209B
  75. Konus-Wind detection of GRB 260127B
  76. EP260209a: COLIBRÍ optical upper limit
  77. Fermi GRB 260210C: Global MASTER-Net observations report
  78. EP260209a: LCO optical upper limits
  79. EP260210a: Global MASTER-Net observations report
  80. EP260210a: refined analysis of the EP-FXT observation
  81. EP260209a: Global MASTER-Net observations report
  82. GRB 260208A: LCO detection of the optical counterpart
  83. EP260209a: Einstein Probe detection of a fast X-ray transient
  84. EP260210a: Optical upper limits with Kinder observations
  85. IPN triangulation of GRB 260207B (short/hard with EE)
  86. GRB 260210C: Fermi GBM Final Real-time Localization
  87. GRB 260210A: Glowbug gamma-ray detection
  88. GRB 260210B: Fermi GBM Final Real-time Localization
  89. EP260210a: SVOM/VT optical upper limit
  90. GRB 260210A: AstroSat CZTI detection
  91. GRB 260208C: AstroSat CZTI detection
  92. EP260210a: COLIBRÍ optical upper limit
  93. EP260210a: SVOM/C-GFT upper limit
  94. GRB 260208B: refined analysis of the EP-FXT observation
  95. EP260210a: Einstein Probe detection of an X-ray transient
  96. GRB 260207B: AstroSat CZTI detection
  97. GRB 260208C: SVOM/GRM observation
  98. GRB 260204A: Swift-XRT afterglow detection
  99. GRB 260208B: AstroSat CZTI detection of a bright long burst
  100. GRB260208A: Liverpool Telescope optical follow-up observations

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