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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"

37226 results found.

  1. EP241111a and EP250125a: Upper limits from SVOM/GRM Observations
  2. GRB 261010A: VLA radio observations
  3. GRB261010A: Keck/MOSFIRE detection of a near-IR source
  4. GRB 261010A: ASKAP non-detection of a radio afterglow
  5. GRB 261010A: LBT tentative near-infrared detection
  6. GRB 261011A: SAO RAS and AbAO optical observations
  7. GRB 261010A: Glowbug gamma-ray detection
  8. GRB 261008A: SVOM/GRM observation
  9. GRB 261009A: GECAM-B detection of a burst
  10. GRB 261010A: initial pulse rest-frame energetics from Konus-Wind detection
  11. GRB 261010A: a short minimum variability timescale and a distinct pulse evolution compatible with a merger origin
  12. GRB 261013A: Fermi GBM Final Real-time Localization
  13. GRB 261011A: Later-epoch J-band upper limit from the SYSU 80 cm infrared telescope
  14. GRID detection of GRB 261010A
  15. GRB 261011A: GECAM-B observation
  16. GRB 261011B: GECAM-B observation
  17. GRB 261010A: J-band upper limit by the SYSU 80cm infrared telescope
  18. GRB 261010A: Swift-XRT refined Analysis
  19. GRB 261011A: Swift-XRT refined Analysis
  20. GRB 261011A: Enhanced Swift-XRT position
  21. GRB 261010A: a Type I-L (merger-driven) GRB candidate
  22. GRB 261011A: 10.4m GTC spectroscopic redshift (z = 2.407)
  23. GRB 261011A: Swift-BAT refined analysis
  24. GRB 261010A: 10.4m GTC spectroscopy of the galaxy 2" from the afterglow
  25. GRB 261011A: REM optical/NIR observations
  26. Konus-Wind detection of GRB 261010A
  27. Konus-Wind detection of GRB 261011A
  28. Konus-Wind detection of GRB 261007A/EP261007a
  29. GRB 261011A: SOAR optical afterglow observations at ~17 hours
  30. GRB 261011A: VLT/X-shooter redshift constraints
  31. GRB 261012A: MAXI GSC detection
  32. GRB 261010A: Swift-BAT refined analysis
  33. GRB 261011A : MITSuME Akeno optical afterglow candidate detection
  34. GRB 261011A: Optical followup from Sichuan South Observatory
  35. GRB 261011A: GMG Optical Observation
  36. GRB 261011A: Liverpool Telescope optical observations
  37. GRB 261011A: J-band observations by the SYSU 80cm infrared telescope
  38. GRB 261010A: NOT confirmation of the optical afterglow
  39. GRB 261010A: Fermi GBM Observation
  40. GRB 261011B: Fermi GBM Final Localization
  41. GRB 261011A: continued LCO optical observations
  42. GRB 261011A: GROWTH-India Telescope optical observations
  43. GRB 261011A: Luminance-band upper limit from a 28cm telescope in Chengde
  44. Swift GRB 261011A: Global MASTER-Net observations report
  45. GRB 261011A: Optical follow-up observations with Kinder
  46. GRB 261011A: SVOM/C-GFT optical observations
  47. GRB 261011A: LCO optical observations
  48. GRB 261011A: SVOM/VT optical observation from VHF data
  49. GRB 261011A: LCO optical observations
  50. GRB 261011A: TRT optical afterglow detection
  51. GRB 261011A: GOTO optical counterpart detection
  52. GRB 261011A: Swift detection of an unusual burst
  53. GRB 261011A: SVOM detection of a long bright burst
  54. GRB 261010A: Enhanced Swift-XRT position
  55. GRB 261010A: possible optical afterglow detected with the 1.5m OSN
  56. GRB 261010A: NOT possible optical counterpart
  57. GRB 261010A: Swift detection of a burst
  58. GRB 261010A: Fermi GBM Final Real-time Localization
  59. GRB 261001A: SVOM/GRM observation
  60. GRB 261009A: Fermi GBM Final Real-time Localization
  61. GRB 261008A: GECAM-B observation
  62. EP261006a: Optical follow-up observations with MATCH
  63. GRB 261007A: SVOM/ECLAIRs refined analysis
  64. GRB 261007A / EP261007a: SVOM/GWAC-F60A/B observations
  65. GRB 261007A: Glowbug gamma-ray detection
  66. GRB 261008A: Fermi GBM Final Real-time Localization
  67. GRB 261007A: NOT optical observations
  68. GRB 261007A: SVOM/GRM observation
  69. GRB 261007A / EP261007a: AstroSat CZTI detection
  70. GRB 261005A: GECAM-B observation
  71. EP261007a/GRB 261007A：Xinglong optical observation
  72. GRB 261007A/EP261007a: Optical follow-up observations with Kinder
  73. EP261006a: Optical follow-up observations with Kinder
  74. GRB 261007A / EP261007a: SVOM/VT optical observations
  75. GRB 261007A: Swift-XRT afterglow detection
  76. GRB 261007A: SVOM/COLIBRÍ (FM-GFT) optical observations
  77. GRB 261007A / EP261007a: NuSTAR detection of prompt emission
  78. GRB 261007A / EP261007a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm telescope at McDonald Observatory
  79. GRB 261007A: Autonomous identification and follow-up of the counterpart to GRB 261007A by BTSbot with ZTF and P60/SEDM
  80. GRB 261007A: GROWTH-India Telescope optical observations
  81. GRB 261007A / EP261007a: TRT optical observations
  82. GRB 261007A: Swift ToO observations
  83. GRB 261007A: SVOM/C-GFT optical observations
  84. GRB 261007A / EP261007a: LCO optical observations
  85. GRB 261007B: Fermi GBM Final Real-time Localization
  86. GRB 261005B: Swift-BAT refined analysis
  87. GRB 261007A: WINTER J-band observations
  88. GRB 261007A: Fermi GBM observation
  89. GRB 261007A / EP261007a: VLT/X-shooter spectroscopic redshift z = 2.101
  90. EP261007a/GRB 261007A: Einstein Probe detection of an X-ray transient
  91. GRB 261007A: KAIT optical counterpart candidate
  92. GRB 261007A: SVOM detection of a burst
  93. GRB 261005B: Swift-XRT refined Analysis
  94. GRB 261005A: Glowbug gamma-ray detection
  95. GRB 261005B: Swift/UVOT Upper Limits
  96. GRB 261005B: J-band upper limit with WINTER
  97. GRB 261001A: GECAM-B observation of a likely long GRB
  98. GRB 261005B: Fermi GBM Observation
  99. GRB 261005B: Enhanced Swift-XRT position
  100. EP trigger 01709320908: Ondrejov D50 observation, fading star suggests stellar flare

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