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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"

32571 results found.

  1. EP260214b: Liverpool Telescope optical observations
  2. GRB 260206A: probable hard X-ray burst from 4U 0513-40
  3. EP260214b: Optical upper limit with Kinder observations
  4. EP260214a: Optical upper limits with Kinder observations
  5. EP260214b: EP-FXT follow-up observation
  6. EP260214a / GRB 260214A: Fermi-GBM Sub-Threshold Detection
  7. EP260214b: DDOTI Optical Detection
  8. EP260214b: GROWTH-India Telescope optical upper limit
  9. EP260214a: VLT near-infrared observation
  10. EP260214b: SVOM/VT optical observation
  11. EP260214a: NOT optical upper limits
  12. EP260214a: COLIBRÍ optical upper limits
  13. EP260214b: OHP/T120 optical observations
  14. EP260214a: refined analysis of the EP-FXT observation
  15. EP260214b: LCO optical counterpart detection
  16. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  17. GRB 260211A: SVOM/VT optical counterpart
  18. EP260214b: COLIBRÍ optical observations
  19. EP260214a: SVOM/VT optical upper limits
  20. EP260214b: NOT optical counterpart detection
  21. EP260214a: Global MASTER-Net observations report
  22. GRB 260212A: AstroSat CZTI detection
  23. GRB 260212A: Fermi GBM Observation
  24. EP260213a: Liverpool Telescope optical upper limits
  25. EP260213a: Global MASTER-Net observations report
  26. EP260213a: COLIBRÍ optical upper limits
  27. GRB 260212A: GECAM-B observation
  28. EP260213a: Optical upper limits with Kinder observations
  29. EP260213a: SVOM/VT optical upper limit
  30. EP260213a: Mondy R-band optical upper limit
  31. EP260213a: NUTTelA-TAO Early Optical Limits
  32. EP260213a: SVOM/C-GFT upper limit
  33. EP260213a: refined analysis of the EP-FXT observation
  34. GRB 260212A: SVOM/GRM observation of a long burst
  35. GRB 260211A - SVOM/ECLAIRs refined analysis
  36. GRB 260204A: SVOM/ECLAIRs refined analysis
  37. GRB 260211A: EP-FXT follow-up observation
  38. GRB 260211A: SVOM/VT optical observation
  39. GRB 260212A: Glowbug gamma-ray detection
  40. GRB 260211A: GOTO optical upper limit
  41. Fermi GRB 260212A: Global MASTER-Net observations report
  42. GRB 260211A: LAST optical upper limit
  43. GRB 260210A: SVOM/GRM observation
  44. Fermi GBM Sub-Threshold Detection of GRB 260211A
  45. Konus-Wind detection of GRB 260207B
  46. GRB 260128B: SVOM/ECLAIRs refined analysis
  47. GRID detection of GRB 260207B
  48. GRB 260211A: LCO optical upper limits
  49. GRB260131A/B: 3.6m DOT Optical Observations
  50. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  51. GRB 260208A: Swift UVOT detection
  52. Konus-Wind detection of GRB 260127B
  53. EP260209a: COLIBRÍ optical upper limit
  54. Fermi GRB 260210C: Global MASTER-Net observations report
  55. EP260209a: LCO optical upper limits
  56. EP260210a: Global MASTER-Net observations report
  57. EP260210a: refined analysis of the EP-FXT observation
  58. EP260209a: Global MASTER-Net observations report
  59. GRB 260208A: LCO detection of the optical counterpart
  60. EP260210a: Optical upper limits with Kinder observations
  61. IPN triangulation of GRB 260207B (short/hard with EE)
  62. GRB 260210A: Glowbug gamma-ray detection
  63. EP260210a: SVOM/VT optical upper limit
  64. GRB 260210A: AstroSat CZTI detection
  65. GRB 260208C: AstroSat CZTI detection
  66. EP260210a: COLIBRÍ optical upper limit
  67. EP260210a: SVOM/C-GFT upper limit
  68. GRB 260208B: refined analysis of the EP-FXT observation
  69. GRB 260207B: AstroSat CZTI detection
  70. GRB 260208C: SVOM/GRM observation
  71. GRB 260204A: Swift-XRT afterglow detection
  72. GRB 260208B: AstroSat CZTI detection of a bright long burst
  73. GRB260208A: Liverpool Telescope optical follow-up observations
  74. GRB 260208A: Glowbug gamma-ray detection
  75. GRB 260208A: NuSTAR detection of prompt emission
  76. GRB 260208A: Fermi GBM Observation
  77. Fermi GRB 260209A: Global MASTER-Net observations report
  78. GRB 260208B: Swift-XRT observations
  79. GRB 260131A/B: continued Mondy optical observations
  80. GRB 260204A: Swift/UVOT Upper Limits
  81. GRB 260208B: COLIBRÍ optical observations
  82. GRB 260208A: Mondy optical observations (duplicate submission)
  83. GRB 260208A: Mondy optical observations
  84. GRB 260208A: 1.3m DFOT optical detection
  85. GRB 260208A: COLIBRÍ optical observations
  86. GRB 260208B: EP-FXT observation
  87. GRB 260208A: NOT spectroscopic redshift z = 2.36
  88. GRB 260208A: Liverpool Telescope optical detection
  89. Fermi GRB 260208C: Global MASTER-Net observations report
  90. GRB 260208B: SVOM/VT optical candidate
  91. GRB 260208A: GECAM-B observation of a bright burst
  92. GRB 260208A: Zwicky Transient Facility Follow-Up of a Fermi GRB (Trigger 792220053)
  93. GRB 260208A: SVOM/VT optical observation
  94. Fermi GRB 260208D: Global MASTER-Net observations report
  95. GRB 260208A: Swift-XRT observations
  96. GRB 260208B: Swift ToO observations
  97. GRB 260208B: SVOM/GRM observation of a bright burst
  98. GRB 260208B: Fermi GBM Detection
  99. GRB 260208B: Fermi-LAT detection
  100. GRB 260208A: Fermi-LAT detection

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