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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. 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"

2852 results found.

  1. GRB 111008A, Swift-BAT refined analysis,
  2. GRB 111008A: Swift detection of a burst
  3. GRB 111005A: Swift-BAT refined analysis
  4. MAXI/GSC detection of a short soft X-ray transient
  5. GRB 110915A, Swift-BAT refined analysis
  6. GRB 110915A: Swift detection of a burst
  7. GRB 110731A: SAO RAS and Terskol observations
  8. IPN triangulation of GRB110825A (very intense, long-duration)
  9. GRB 110808A: Swift detection of a burst with optical counterpart
  10. GRB 110801A: Swift detection of a burst with an optical counterpart
  11. GRB110731A: Swift/UVOT Observations
  12. GRB 110731A: Swift detection of a burst with an optical counterpart
  13. IPN triangulation of GRB 110721A
  14. Konus-Wind observation of GRB 110709A
  15. Konus-Wind observation of GRB 110709B
  16. GRB110709A: upper limits from CAHA 1.23m and OSN 1.5m
  17. Swift-BAT trigger 456532 is not astrophysical
  18. SGR 1E 1841-045: Swift detection of a soft gamma repeater burst
  19. IPN triangulation of GRB110618A (long duration, extremely intense)
  20. Fermi Gamma-ray Burst Monitor trigger 110621949 is not a GRB
  21. GRB 110604A: Suzaku WAM observation of the prompt emission
  22. GRB 110530A: MASTER OT observations
  23. GRB 110530A: MITSuME Akeno Optical Observation
  24. GRB 110422A: MASTER first 30 min OT light curve
  25. GRB 110422A: MASTER earlier OT polarization observations
  26. GRB 110420B: Fermi GBM observation
  27. GRB 110420B: Swift detection of a short hard burst
  28. GRB110414A: MITSuME Okayama Optical upper limits
  29. GRB 110414A: Swift detection of a burst
  30. GRB 110411A: MASTER prompt and follow-up optical limits
  31. GRB 110411A : Xinglong TNT OT candidate
  32. GRB 110411A, Swift-BAT refined analysis
  33. GRB 110411A: Enhanced Swift-XRT position
  34. GRB 110411A: Swift detection of a burst
  35. GRB 110328A / Swift J164449.3+573451: MASTER pre, prompt and follow-up observations
  36. GRB 110407A: Enhanced Swift-XRT position
  37. GRB 100407A : Errata of afterglow position in GCN 11899
  38. GRB 110407A : Lulin optical afterglow detection
  39. GRB 110407A: Prompt enhanced Swift-XRT position
  40. GRB 110407A: Swift detection of a burst
  41. Konus-Wind observation of GRB 110406A
  42. GRB 110213A, the review of the sky area in plate archives
  43. GRB 110213B: Swift XRT observation
  44. GRB 110212A, Swift-BAT refined analysis
  45. GRB 110212A: Swift detection of a burst
  46. GRB110205A: MITSuME Ishigakijima Optical Observation
  47. GRB 101112A: Maidanak and CrAO optical observations
  48. Konus-Wind observation of GRB 110120A
  49. GRB 101224A, the review of the sky area in plate archives
  50. GRB 101225A: CQUEAN optical observation
  51. GRB 101225a
  52. Short GRB 110106A: MASTER OT observations
  53. GRB 101224A: Swift-XRT refined Analysis
  54. GRB 101224A, Swift-BAT refined analysis
  55. GRB 101224A - UVOT-enhanced XRT position
  56. GRB 101224A: Swift detection of a short burst
  57. GRB 101123A: Fermi GBM detection
  58. Optical observation of GRB 101024A
  59. GRB 101114A: GROND Upper limits
  60. GRB 090113, the review of the sky area in plate archives
  61. GRB 090111, the review of the sky area in plate archives (1976-1996)
  62. GRB 101024A: GROND optical/NIR observations
  63. GRB 101020A, Swift-BAT refined analysis
  64. GRB 101008A: optical observations
  65. GRB 101017A: ROTSE-III Optical Limits
  66. GRB100906A: Ashra-1 observation of early optical emission
  67. GRB 100909A: Faulkes Telescope North afterglow candidate
  68. GRB 100901A: Kanata Telescope observation of the optical afterglow
  69. GRB 100902A: MASTER Prompt Optical Observations
  70. GRB 100901A : HCT optical observations
  71. IPN triangulation of GRB 100826A
  72. GRB 100814A: ISON-NM optical observations
  73. GRB 100805A: IAC80 BVR-band observations
  74. GRB 100805A: Swift detection of a burst with an optical counterpart
  75. GRB 100728B: optical detection
  76. GRB 100728A: Swift detection of a burst
  77. GRB 100727A: Fermi GBM observation
  78. GRB 100727A: Swift detection of a burst
  79. GRB 100724B: Suzaku WAM observation of the prompt emission
  80. GRB 100724B: gamma-ray detection by AGILE
  81. Konus-Wind observation of GRB 100724B
  82. GRB 100724B: Fermi LAT and GBM analysis
  83. GRB 100724B: Fermi GBM detection
  84. GRB 100724A: Swift detection of a burst
  85. GRB 100713A : IRSF/SIRIUS NIR upper limits
  86. IPN triangulation of GRB 100707A
  87. XRF 100701A : MAXI/GSC detection of a probable XRF
  88. XRF 100616a : MAXI/GSC detection of a probable XRF
  89. GRB 100614A: MASTER-Net optical alert observations
  90. GRB 100614 : XMM-Newton observation
  91. Trigger 424161: Swift/BAT trigger on XTE J1946+274/GRO J1944+26
  92. GRB 100518A: Swift target of opportunity observation of the INTEGRAL burst
  93. GRB 100513A: MITSuME Akeno Optical Observation
  94. GRB 100513A, RIMOTS optical upper limits
  95. GRB 100510A: MAXI/GSC detection
  96. GRB 100511A, RIMOTS optical upper limits
  97. GRB 100508A: Enhanced Swift-XRT position
  98. GRB100508A: Swift/UVOT Detection of the Afterglow
  99. GRB 100508A: Swift detection of a burst
  100. GRB 100504A: SARA-South Upper Limit

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