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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"

32693 results found.

  1. EP260221a: Xinglong optical upper limit
  2. Fermi GRB 260221A: Global MASTER-Net observations report
  3. EP260221a: GOTO optical upper limit
  4. EP260221a: COLIBRÍ optical upper limit
  5. SVOM alert sb26021801: LCO optical upper limit
  6. GRB 260219A: AstroSat CZTI detection
  7. IceCube-260217A: Upper limits from a search for additional neutrino events in IceCube
  8. GRB 260219A: GECAM-B observation of a long burst
  9. Fermi GRB 260219A: Global MASTER-Net observations report
  10. SVOM alert sb26021801: LAST optical upper limit
  11. sb26021801: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  12. Fermi-LAT Gamma-ray Observations of IceCube-260217A
  13. GRB 260214B/EP260214b: SVOM/ECLAIRs detection through targeted search
  14. EP260214b: Mondy optical observations
  15. EP260214b: 1.3m DFOT optical upper limit
  16. EP260210a: Mondy optical upper limits
  17. Konus-Wind detection of GRB 260212A
  18. GRB 260208A: AbAO and Terskol optical upper limits
  19. GRB 260208A: continued Mondy optical observations
  20. IPN triangulation of GRB 260212A
  21. IceCube-260217A - IceCube observation of a high-energy neutrino candidate track-like event
  22. GRB 260213A: GECAM-B observation of a short burst
  23. EP260214b: Liverpool Telescope optical observations
  24. GRB 260206A: probable hard X-ray burst from 4U 0513-40
  25. EP260214b: Optical upper limit with Kinder observations
  26. EP260214a: Optical upper limits with Kinder observations
  27. EP260214b: EP-FXT follow-up observation
  28. EP260214a / GRB 260214A: Fermi-GBM Sub-Threshold Detection
  29. EP260214b: DDOTI Optical Detection
  30. EP260214b: GROWTH-India Telescope optical upper limit
  31. EP260214a: VLT near-infrared observation
  32. EP260214b: SVOM/VT optical observation
  33. EP260214a: NOT optical upper limits
  34. EP260214a: COLIBRÍ optical upper limits
  35. EP260214b: OHP/T120 optical observations
  36. EP260214a: refined analysis of the EP-FXT observation
  37. EP260214b: LCO optical counterpart detection
  38. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  39. GRB 260211A: SVOM/VT optical counterpart
  40. EP260214b: COLIBRÍ optical observations
  41. EP260214a: SVOM/VT optical upper limits
  42. EP260214b: NOT optical counterpart detection
  43. EP260214a: Global MASTER-Net observations report
  44. GRB 260212A: AstroSat CZTI detection
  45. GRB 260212A: Fermi GBM Observation
  46. EP260213a: Liverpool Telescope optical upper limits
  47. EP260213a: Global MASTER-Net observations report
  48. EP260213a: COLIBRÍ optical upper limits
  49. GRB 260212A: GECAM-B observation
  50. EP260213a: Optical upper limits with Kinder observations
  51. EP260213a: SVOM/VT optical upper limit
  52. EP260213a: Mondy R-band optical upper limit
  53. EP260213a: NUTTelA-TAO Early Optical Limits
  54. EP260213a: SVOM/C-GFT upper limit
  55. EP260213a: refined analysis of the EP-FXT observation
  56. GRB 260212A: SVOM/GRM observation of a long burst
  57. GRB 260211A - SVOM/ECLAIRs refined analysis
  58. GRB 260204A: SVOM/ECLAIRs refined analysis
  59. GRB 260211A: EP-FXT follow-up observation
  60. GRB 260211A: SVOM/VT optical observation
  61. GRB 260212A: Glowbug gamma-ray detection
  62. GRB 260211A: GOTO optical upper limit
  63. Fermi GRB 260212A: Global MASTER-Net observations report
  64. GRB 260211A: LAST optical upper limit
  65. GRB 260210A: SVOM/GRM observation
  66. Fermi GBM Sub-Threshold Detection of GRB 260211A
  67. Konus-Wind detection of GRB 260207B
  68. GRB 260128B: SVOM/ECLAIRs refined analysis
  69. GRID detection of GRB 260207B
  70. GRB 260211A: LCO optical upper limits
  71. GRB260131A/B: 3.6m DOT Optical Observations
  72. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  73. GRB 260208A: Swift UVOT detection
  74. Konus-Wind detection of GRB 260127B
  75. EP260209a: COLIBRÍ optical upper limit
  76. Fermi GRB 260210C: Global MASTER-Net observations report
  77. EP260209a: LCO optical upper limits
  78. EP260210a: Global MASTER-Net observations report
  79. EP260210a: refined analysis of the EP-FXT observation
  80. EP260209a: Global MASTER-Net observations report
  81. GRB 260208A: LCO detection of the optical counterpart
  82. EP260210a: Optical upper limits with Kinder observations
  83. IPN triangulation of GRB 260207B (short/hard with EE)
  84. GRB 260210A: Glowbug gamma-ray detection
  85. EP260210a: SVOM/VT optical upper limit
  86. GRB 260210A: AstroSat CZTI detection
  87. GRB 260208C: AstroSat CZTI detection
  88. EP260210a: COLIBRÍ optical upper limit
  89. EP260210a: SVOM/C-GFT upper limit
  90. GRB 260208B: refined analysis of the EP-FXT observation
  91. GRB 260207B: AstroSat CZTI detection
  92. GRB 260208C: SVOM/GRM observation
  93. GRB 260204A: Swift-XRT afterglow detection
  94. GRB 260208B: AstroSat CZTI detection of a bright long burst
  95. GRB260208A: Liverpool Telescope optical follow-up observations
  96. GRB 260208A: Glowbug gamma-ray detection
  97. GRB 260208A: NuSTAR detection of prompt emission
  98. GRB 260208A: Fermi GBM Observation
  99. Fermi GRB 260209A: Global MASTER-Net observations report
  100. GRB 260208B: Swift-XRT observations

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