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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"

32706 results found.

  1. EP260223a: COLIBRÍ optical upper limits
  2. GRB 260223A: SVOM/VT optical observation
  3. GRB 260223A: SVOM/GRM observation
  4. GRB 260223A: COLIBRÍ further optical observations and a brightening
  5. EP260221a: Optical upper limit with Kinder observations
  6. GRB 260223A: COLIBRÍ optical observations
  7. GRB 260223A: DDOTI Optical Candidate
  8. Fermi GRB 260223A: Global MASTER-Net observations report
  9. EP260221a: Liverpool Telescope detection of COLIBRÍ counterpart candidate
  10. EP260221a: COLIBRÍ optical counterpart candidate
  11. EP260221a: Gemini South z-band upper limit
  12. EP260221a: Global MASTER-Net observations report
  13. EP260221a: EP-FXT follow-up observation
  14. Fermi GRB 260221B: Global MASTER-Net observations report
  15. EP260221a: Xinglong optical upper limit
  16. Fermi GRB 260221A: Global MASTER-Net observations report
  17. EP260221a: GOTO optical upper limit
  18. EP260221a: COLIBRÍ optical upper limit
  19. SVOM alert sb26021801: LCO optical upper limit
  20. GRB 260219A: AstroSat CZTI detection
  21. IceCube-260217A: Upper limits from a search for additional neutrino events in IceCube
  22. GRB 260219A: GECAM-B observation of a long burst
  23. Fermi GRB 260219A: Global MASTER-Net observations report
  24. SVOM alert sb26021801: LAST optical upper limit
  25. sb26021801: SVOM/COLIBRÍ (FM-GFT) optical upper limit
  26. Fermi-LAT Gamma-ray Observations of IceCube-260217A
  27. GRB 260214B/EP260214b: SVOM/ECLAIRs detection through targeted search
  28. EP260214b: Mondy optical observations
  29. EP260214b: 1.3m DFOT optical upper limit
  30. EP260210a: Mondy optical upper limits
  31. Konus-Wind detection of GRB 260212A
  32. GRB 260208A: AbAO and Terskol optical upper limits
  33. GRB 260208A: continued Mondy optical observations
  34. IPN triangulation of GRB 260212A
  35. IceCube-260217A - IceCube observation of a high-energy neutrino candidate track-like event
  36. GRB 260213A: GECAM-B observation of a short burst
  37. EP260214b: Liverpool Telescope optical observations
  38. GRB 260206A: probable hard X-ray burst from 4U 0513-40
  39. EP260214b: Optical upper limit with Kinder observations
  40. EP260214a: Optical upper limits with Kinder observations
  41. EP260214b: EP-FXT follow-up observation
  42. EP260214a / GRB 260214A: Fermi-GBM Sub-Threshold Detection
  43. EP260214b: DDOTI Optical Detection
  44. EP260214b: GROWTH-India Telescope optical upper limit
  45. EP260214a: VLT near-infrared observation
  46. EP260214b: SVOM/VT optical observation
  47. EP260214a: NOT optical upper limits
  48. EP260214a: COLIBRÍ optical upper limits
  49. EP260214b: OHP/T120 optical observations
  50. EP260214a: refined analysis of the EP-FXT observation
  51. EP260214b: LCO optical counterpart detection
  52. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  53. GRB 260211A: SVOM/VT optical counterpart
  54. EP260214b: COLIBRÍ optical observations
  55. EP260214a: SVOM/VT optical upper limits
  56. EP260214b: NOT optical counterpart detection
  57. EP260214a: Global MASTER-Net observations report
  58. GRB 260212A: AstroSat CZTI detection
  59. GRB 260212A: Fermi GBM Observation
  60. EP260213a: Liverpool Telescope optical upper limits
  61. EP260213a: Global MASTER-Net observations report
  62. EP260213a: COLIBRÍ optical upper limits
  63. GRB 260212A: GECAM-B observation
  64. EP260213a: Optical upper limits with Kinder observations
  65. EP260213a: SVOM/VT optical upper limit
  66. EP260213a: Mondy R-band optical upper limit
  67. EP260213a: NUTTelA-TAO Early Optical Limits
  68. EP260213a: SVOM/C-GFT upper limit
  69. EP260213a: refined analysis of the EP-FXT observation
  70. GRB 260212A: SVOM/GRM observation of a long burst
  71. GRB 260211A - SVOM/ECLAIRs refined analysis
  72. GRB 260204A: SVOM/ECLAIRs refined analysis
  73. GRB 260211A: EP-FXT follow-up observation
  74. GRB 260211A: SVOM/VT optical observation
  75. GRB 260212A: Glowbug gamma-ray detection
  76. GRB 260211A: GOTO optical upper limit
  77. Fermi GRB 260212A: Global MASTER-Net observations report
  78. GRB 260211A: LAST optical upper limit
  79. GRB 260210A: SVOM/GRM observation
  80. Fermi GBM Sub-Threshold Detection of GRB 260211A
  81. Konus-Wind detection of GRB 260207B
  82. GRB 260128B: SVOM/ECLAIRs refined analysis
  83. GRID detection of GRB 260207B
  84. GRB 260211A: LCO optical upper limits
  85. GRB260131A/B: 3.6m DOT Optical Observations
  86. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  87. GRB 260208A: Swift UVOT detection
  88. Konus-Wind detection of GRB 260127B
  89. EP260209a: COLIBRÍ optical upper limit
  90. Fermi GRB 260210C: Global MASTER-Net observations report
  91. EP260209a: LCO optical upper limits
  92. EP260210a: Global MASTER-Net observations report
  93. EP260210a: refined analysis of the EP-FXT observation
  94. EP260209a: Global MASTER-Net observations report
  95. GRB 260208A: LCO detection of the optical counterpart
  96. EP260210a: Optical upper limits with Kinder observations
  97. IPN triangulation of GRB 260207B (short/hard with EE)
  98. GRB 260210A: Glowbug gamma-ray detection
  99. EP260210a: SVOM/VT optical upper limit
  100. GRB 260210A: AstroSat CZTI detection

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