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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"

2440 results found.

  1. EP260214a: COLIBRÍ optical upper limits
  2. EP260214b: OHP/T120 optical observations
  3. EP260214a: refined analysis of the EP-FXT observation
  4. EP260214b: LCO optical counterpart detection
  5. EP260214b: VLT/X-shooter spectroscopic redshift z = 1.208
  6. GRB 260211A: SVOM/VT optical counterpart
  7. EP260214b: COLIBRÍ optical observations
  8. EP260214a: SVOM/VT optical upper limits
  9. EP260214b: Einstein Probe detection of a fast X-ray transient
  10. EP260214a: Global MASTER-Net observations report
  11. EP260214a: Einstein Probe detection of an X-ray transient
  12. GRB 260212A: AstroSat CZTI detection
  13. GRB 260212A: Fermi GBM Observation
  14. EP260213a: Liverpool Telescope optical upper limits
  15. EP260213a: Global MASTER-Net observations report
  16. EP260213a: COLIBRÍ optical upper limits
  17. GRB 260212A: GECAM-B observation
  18. EP260213a: Optical upper limits with Kinder observations
  19. EP260213a: SVOM/VT optical upper limit
  20. EP260213a: Mondy R-band optical upper limit
  21. EP260213a: NUTTelA-TAO Early Optical Limits
  22. EP260213a: SVOM/C-GFT upper limit
  23. EP260213a: refined analysis of the EP-FXT observation
  24. EP260213a: Einstein Probe detection of a fast X-ray transient
  25. EP/WXT 01709258378: NOT optical upper limits
  26. GRB 260212A: SVOM/GRM observation of a long burst
  27. GRB 260213B: Fermi GBM Final Localization
  28. GRB 260213B: BALROG localization (Fermi Trigger 792697214 / GRB 260213736)
  29. GRB 260211A - SVOM/ECLAIRs refined analysis
  30. GRB 260204A: SVOM/ECLAIRs refined analysis
  31. GRB 260213A: Fermi GBM Final Localization
  32. GRB 260211A: EP-FXT follow-up observation
  33. GRB 260211A: SVOM/VT optical observation
  34. GRB 260212A: Glowbug gamma-ray detection
  35. GRB 260211A: GOTO optical upper limit
  36. Fermi GRB 260212A: Global MASTER-Net observations report
  37. GRB 260212A: Fermi GBM Final Real-time Localization
  38. GRB 260211A: LAST optical upper limit
  39. GRB 260210A: SVOM/GRM observation
  40. Fermi GBM Sub-Threshold Detection of GRB 260211A
  41. GRB 260128B: SVOM/ECLAIRs refined analysis
  42. GRID detection of GRB 260207B
  43. GRB 260211A: LCO optical upper limits
  44. GRB260131A/B: 3.6m DOT Optical Observations
  45. GRB 260211A: SVOM/COLIBRÍ (FM-GFT) optical upper limits
  46. Fermi trigger No 792537871: Global MASTER-Net observations report
  47. GRB 260211A: SVOM detection of a burst
  48. EP260209a: COLIBRÍ optical upper limit
  49. Fermi GRB 260210C: Global MASTER-Net observations report
  50. EP260209a: LCO optical upper limits
  51. EP260210a: Global MASTER-Net observations report
  52. EP260210a: refined analysis of the EP-FXT observation
  53. EP260209a: Global MASTER-Net observations report
  54. GRB 260208A: LCO detection of the optical counterpart
  55. EP260209a: Einstein Probe detection of a fast X-ray transient
  56. EP260210a: Optical upper limits with Kinder observations
  57. GRB 260210C: Fermi GBM Final Real-time Localization
  58. GRB 260210A: Glowbug gamma-ray detection
  59. GRB 260210B: Fermi GBM Final Real-time Localization
  60. EP260210a: SVOM/VT optical upper limit
  61. GRB 260210A: AstroSat CZTI detection
  62. GRB 260208C: AstroSat CZTI detection
  63. EP260210a: COLIBRÍ optical upper limit
  64. EP260210a: SVOM/C-GFT upper limit
  65. GRB 260208B: refined analysis of the EP-FXT observation
  66. EP260210a: Einstein Probe detection of an X-ray transient
  67. GRB 260207B: AstroSat CZTI detection
  68. GRB 260208C: SVOM/GRM observation
  69. GRB 260208B: AstroSat CZTI detection of a bright long burst
  70. GRB260208A: Liverpool Telescope optical follow-up observations
  71. GRB 260208A: Glowbug gamma-ray detection
  72. GRB 260208A: NuSTAR detection of prompt emission
  73. GRB 260208A: Fermi GBM Observation
  74. Fermi GRB 260209A: Global MASTER-Net observations report
  75. GRB 260131A/B: continued Mondy optical observations
  76. GRB 260208B: COLIBRÍ optical observations
  77. GRB 260208A: Mondy optical observations
  78. GRB 260208A: 1.3m DFOT optical detection
  79. GRB 260208A: COLIBRÍ optical observations
  80. GRB 260208B: EP-FXT observation
  81. GRB 260208A: NOT spectroscopic redshift z = 2.36
  82. GRB 260208A: Liverpool Telescope optical detection
  83. Fermi GRB 260208C: Global MASTER-Net observations report
  84. GRB 260208B: SVOM/VT optical candidate
  85. GRB 260208A: GECAM-B observation of a bright burst
  86. GRB 260208A: Zwicky Transient Facility Follow-Up of a Fermi GRB (Trigger 792220053)
  87. GRB 260209A: Fermi GBM Final Real-time Localization
  88. GRB 260208A: SVOM/VT optical observation
  89. Fermi GRB 260208D: Global MASTER-Net observations report
  90. GRB 260208D: Fermi GBM Final Real-time Localization
  91. GRB 260208B: SVOM/GRM observation of a bright burst
  92. GRB 260208B: Fermi GBM Detection
  93. LAT GRB 260208B: Global MASTER-Net observations report
  94. GRB 260208B: Fermi-LAT detection
  95. GRB 260208C: Fermi GBM Final Real-time Localization
  96. GRB 260208A: Fermi-LAT detection
  97. GRB 260207B: GECAM-B observation
  98. GRB 260208A: Fermi GBM Classification Correction
  99. GRB 260208A: GOTO detection of a potential optical counterpart (GOTO26aob)
  100. GRB 260208B: BALROG localization (Fermi Trigger 792237169 / GRB 260208412)

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