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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"

32688 results found.

  1. SVOM alert sb26021801: LCO optical upper limit
  2. GRB 260219A: AstroSat CZTI detection
  3. IceCube-260217A: Upper limits from a search for additional neutrino events in IceCube
  4. GRB 260219A: GECAM-B observation of a long burst
  5. Fermi GRB 260219A: Global MASTER-Net observations report
  6. SVOM alert sb26021801: LAST optical upper limit
  7. sb26021801: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  8. Fermi-LAT Gamma-ray Observations of IceCube-260217A
  9. GRB 260214B/EP260214b: SVOM/ECLAIRs detection through targeted search
  10. EP260214b: Mondy optical observations
  11. EP260214b: 1.3m DFOT optical upper limit
  12. EP260210a: Mondy optical upper limits
  13. Konus-Wind detection of GRB 260212A
  14. GRB 260208A: AbAO and Terskol optical upper limits
  15. GRB 260208A: continued Mondy optical observations
  16. IPN triangulation of GRB 260212A
  17. IceCube-260217A - IceCube observation of a high-energy neutrino candidate track-like event
  18. GRB 260213A: GECAM-B observation of a short burst
  19. EP260214b: Liverpool Telescope optical observations
  20. GRB 260206A: probable hard X-ray burst from 4U 0513-40
  21. EP260214b: Optical upper limit with Kinder observations
  22. EP260214a: Optical upper limits with Kinder observations
  23. EP260214b: EP-FXT follow-up observation
  24. EP260214a / GRB 260214A: Fermi-GBM Sub-Threshold Detection
  25. EP260214b: DDOTI Optical Detection
  26. EP260214b: GROWTH-India Telescope optical upper limit
  27. EP260214a: VLT near-infrared observation
  28. EP260214b: SVOM/VT optical observation
  29. EP260214a: NOT optical upper limits
  30. EP260214a: COLIBRÍ optical upper limits
  31. EP260214b: OHP/T120 optical observations
  32. EP260214a: refined analysis of the EP-FXT observation
  33. EP260214b: LCO optical counterpart detection
  34. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  35. GRB 260211A: SVOM/VT optical counterpart
  36. EP260214b: COLIBRÍ optical observations
  37. EP260214a: SVOM/VT optical upper limits
  38. EP260214b: NOT optical counterpart detection
  39. EP260214a: Global MASTER-Net observations report
  40. GRB 260212A: AstroSat CZTI detection
  41. GRB 260212A: Fermi GBM Observation
  42. EP260213a: Liverpool Telescope optical upper limits
  43. EP260213a: Global MASTER-Net observations report
  44. EP260213a: COLIBRÍ optical upper limits
  45. GRB 260212A: GECAM-B observation
  46. EP260213a: Optical upper limits with Kinder observations
  47. EP260213a: SVOM/VT optical upper limit
  48. EP260213a: Mondy R-band optical upper limit
  49. EP260213a: NUTTelA-TAO Early Optical Limits
  50. EP260213a: SVOM/C-GFT upper limit
  51. EP260213a: refined analysis of the EP-FXT observation
  52. GRB 260212A: SVOM/GRM observation of a long burst
  53. GRB 260211A - SVOM/ECLAIRs refined analysis
  54. GRB 260204A: SVOM/ECLAIRs refined analysis
  55. GRB 260211A: EP-FXT follow-up observation
  56. GRB 260211A: SVOM/VT optical observation
  57. GRB 260212A: Glowbug gamma-ray detection
  58. GRB 260211A: GOTO optical upper limit
  59. Fermi GRB 260212A: Global MASTER-Net observations report
  60. GRB 260211A: LAST optical upper limit
  61. GRB 260210A: SVOM/GRM observation
  62. Fermi GBM Sub-Threshold Detection of GRB 260211A
  63. Konus-Wind detection of GRB 260207B
  64. GRB 260128B: SVOM/ECLAIRs refined analysis
  65. GRID detection of GRB 260207B
  66. GRB 260211A: LCO optical upper limits
  67. GRB260131A/B: 3.6m DOT Optical Observations
  68. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  69. GRB 260208A: Swift UVOT detection
  70. Konus-Wind detection of GRB 260127B
  71. EP260209a: COLIBRÍ optical upper limit
  72. Fermi GRB 260210C: Global MASTER-Net observations report
  73. EP260209a: LCO optical upper limits
  74. EP260210a: Global MASTER-Net observations report
  75. EP260210a: refined analysis of the EP-FXT observation
  76. EP260209a: Global MASTER-Net observations report
  77. GRB 260208A: LCO detection of the optical counterpart
  78. EP260210a: Optical upper limits with Kinder observations
  79. IPN triangulation of GRB 260207B (short/hard with EE)
  80. GRB 260210A: Glowbug gamma-ray detection
  81. EP260210a: SVOM/VT optical upper limit
  82. GRB 260210A: AstroSat CZTI detection
  83. GRB 260208C: AstroSat CZTI detection
  84. EP260210a: COLIBRÍ optical upper limit
  85. EP260210a: SVOM/C-GFT upper limit
  86. GRB 260208B: refined analysis of the EP-FXT observation
  87. GRB 260207B: AstroSat CZTI detection
  88. GRB 260208C: SVOM/GRM observation
  89. GRB 260204A: Swift-XRT afterglow detection
  90. GRB 260208B: AstroSat CZTI detection of a bright long burst
  91. GRB260208A: Liverpool Telescope optical follow-up observations
  92. GRB 260208A: Glowbug gamma-ray detection
  93. GRB 260208A: NuSTAR detection of prompt emission
  94. GRB 260208A: Fermi GBM Observation
  95. Fermi GRB 260209A: Global MASTER-Net observations report
  96. GRB 260208B: Swift-XRT observations
  97. GRB 260131A/B: continued Mondy optical observations
  98. GRB 260204A: Swift/UVOT Upper Limits
  99. GRB 260208B: COLIBRÍ optical observations
  100. GRB 260208A: Mondy optical observations (duplicate submission)

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