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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"

36004 results found.

  1. GRB 261007A: AstroSat CZTI detection
  2. GRB 261005A: GECAM-B observation
  3. EP261007a/GRB 261007A：Xinglong optical observation
  4. GRB 261007A/EP261007a: Optical follow-up observations with Kinder
  5. GRB 261007A / EP261007a: SVOM/VT optical observations
  6. GRB 261007A: Swift-XRT afterglow detection
  7. GRB 261007A: SVOM/COLIBRÍ (FM-GFT) optical observations
  8. GRB 261007A / EP261007a: NuSTAR detection of prompt emission
  9. GRB 261007A / EP261007a: ULL-ASTRO-MASTER detection of the optical afterglow with LCO 40-cm telescope at McDonald Observatory
  10. GRB 261007A: Autonomous identification and follow-up of the counterpart to GRB 261007A by BTSbot with ZTF and P60/SEDM
  11. GRB 261007A: GROWTH-India Telescope optical observations
  12. GRB 261007A / EP261007a: TRT optical observations
  13. GRB 261007A: Swift ToO observations
  14. GRB 261007A: SVOM/C-GFT optical observations
  15. GRB 261007A / EP261007a: LCO optical observations
  16. GRB 261007B: Fermi GBM Final Real-time Localization
  17. GRB 261005B: Swift-BAT refined analysis
  18. GRB 261007A: WINTER J-band observations
  19. GRB 261007A: Fermi GBM observation
  20. GRB 261007A / EP261007a: VLT/X-shooter spectroscopic redshift z = 2.101
  21. EP261007a/GRB 261007A: Einstein Probe detection of an X-ray transient
  22. GRB 261007A: KAIT optical counterpart candidate
  23. GRB 261007A: SVOM detection of a burst
  24. GRB 261005B: Swift-XRT refined Analysis
  25. GRB 261005A: Glowbug gamma-ray detection
  26. GRB 261005B: Swift/UVOT Upper Limits
  27. GRB 261005B: J-band upper limit with WINTER
  28. GRB 261001A: GECAM-B observation of a likely long GRB
  29. GRB 261005B: Fermi GBM Observation
  30. GRB 261005B: Enhanced Swift-XRT position
  31. EP trigger 01709320908: Ondrejov D50 observation, fading star suggests stellar flare
  32. GRB 261005B: Swift detection of a burst
  33. GRB 261005A: Fermi GBM Final Real-time Localization
  34. GRB 261003A: Glowbug gamma-ray detection of a likely short burst
  35. GRB 261002A: Fermi GBM Final Localization
  36. GRB 260930B: SVOM/GRM observation
  37. Konus-Wind detection of GRB 260919A / EP 260920a
  38. GRB 260921B: GECAM-B observation
  39. GRB 260930B: GECAM-B detection of a burst
  40. Fermi GRB 261003A: Global MASTER-Net observations report
  41. GRB 261003A: Fermi GBM Final Real-time Localization
  42. Fermi GBM Detection of GRB 260919A / EP260920a
  43. IPN triangulation of GRB 260919A / EP260920a
  44. Fermi GRB 260930B: Global MASTER-Net observations report
  45. GRB 260926C: SVOM/GRM observation
  46. GRB 260930B: Fermi GBM Final Real-time Localization
  47. GRB 260930A: Fermi GBM Final Real-time Localization
  48. GRB 260926C: AstroSat CZTI detection
  49. GRB 260926C: GECAM-B observation
  50. GRB 260926A: GECAM-B observation
  51. GRB 260926B: Glowbug gamma-ray detection of a likely short burst
  52. GRB 260926A: Glowbug gamma-ray detection
  53. GRB 260924A: VLA detection
  54. GRB 260924A: Swift/UVOT UV grism spectrum results
  55. GRB 260924A: AbAO optical observations
  56. Fermi GRB 260928A: Global MASTER-Net observations report
  57. GRB 260928A: Fermi GBM Final Real-time Localization
  58. GRB 260925A: Swift-BAT refined analysis
  59. GRB 260924A: Upper limits from a neutrino search with IceCube
  60. Fermi GRB 260926C: Global MASTER-Net observations report
  61. GRB 260926C: Fermi GBM Final Real-time Localization
  62. GRB260914A: MAO/AZT-22 optical observations
  63. GRB 260926B: Fermi GBM Final Real-time Localization
  64. Fermi GRB 260926A: Global MASTER-Net observations report
  65. GRB 260924A: Near-infrared detection with MDM/MIRAGE
  66. GRB 260926A: Fermi GBM Final Real-time Localization
  67. GRB 260924A: COLIBRÍ optical observations
  68. GRB 260924A: Second-epoch J-band upper limit from the SYSU 80 cm infrared telescope
  69. GRB 260925A: J-band upper limit by SYSU 80cm infrared telescope
  70. GRB 260925A: Swift-XRT refined Analysis
  71. Swift Trigger 1513439 is probably not a GRB
  72. GRB 260925A: Swift/UVOT Upper Limits
  73. Konus-Wind detection of GRB 260924A
  74. GRB 260924A: Extreme Isotropic-equivalent Gamma-ray Energy and encouragement for multiwavelength follow-up observations
  75. GRB 260923A: Glowbug gamma-ray detection
  76. GRB 260924A: Optical follow-up observations with Kinder
  77. GRB 260922A: Glowbug gamma-ray detection
  78. GRB 260925A: Enhanced Swift-XRT position
  79. GRB 260925A: COLIBRÍ optical upper limits
  80. GRB 260925A: FRAM-Auger optical limit
  81. GRB 260924A: Ondrejov D50 optical afterglow detection
  82. GRB 260924A: SVOM/GRM observation
  83. GRB 260924A: 2.2m CAHA spectroscopic redshift z = 3.51
  84. GRB 260925A: Swift detection of a burst
  85. GRB 260923A: Insight-HXMT/HE detection
  86. GRB 260924A: J-band observations by the SYSU 80 cm infrared telescope
  87. GRB 260924A: Swift/UVOT Detection
  88. GRB 260924A: GROWTH-India Telescope optical observations
  89. GRB 260924A: Swift-BAT refined analysis
  90. GRB 260924A: NuSTAR detection of prompt emission
  91. GRB 260924A: Swift/UVOT Upper Limits
  92. GRB 260924A: Swift-XRT refined Analysis
  93. Konus-Wind detection of GRB 260922A
  94. GRB 260922A: NuSTAR detection of prompt emission
  95. GRB 260921A: NuSTAR detection of prompt emission
  96. Konus-Wind detection of GRB 260921A (correction to GCN 45722)
  97. GRB 260921A: SVOM/GRM observation
  98. GRB 260922A: COLIBRÍ Confirmation of the Optical Counterpart
  99. GRB 260924A: Fermi GRB Observation
  100. Konus-Wind detection of GRB 260921A (possible merger-origin)

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