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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"

20562 results found.

  1. GRB001109, Radio observations
  2. GRB 991208: HST Imaging of the Host Galaxy
  3. GRB000926: R-image of the host galaxy
  4. GRB 001025B, I-band observations
  5. GRB001025B, Radio observations
  6. GRB 001025 Optical Observations
  7. GRB001007: Optical observations
  8. GRB001007, Radio observations
  9. GRB001019, Optical Observations
  10. GRB 001018, Possible Radio Afterglow
  11. GRB001018, Gamma Ray Observations
  12. V,R,I band observations of GRB000926
  13. The Likely Optical/Infrared Afterglow of GRB 001011
  14. GRB 001007, BVR-band observations
  15. GRB000926 - Amateur Optical Observations
  16. GRB001007: Optical observations
  17. GRB 000926 : the host galaxy
  18. HETE-2 Launches Successfully
  19. GRB 000926 Chandra Observation
  20. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  21. GRB000926 - Optical observations
  22. GRB000926 - Optical observations
  23. GRB000926 - Optical observations
  24. GRB000926 - Optical observations
  25. GRB 000926: optical observations
  26. GRB 000926, Optical Observations
  27. GRB000926 - Optical observations
  28. GRB000911: optical VLT observations
  29. GRB000926 K'-band Observation
  30. GRB000926 optical observations
  31. GRB000926 - Optical observations
  32. J and K band observations of GRB 000926
  33. GRB000911 Optical Observations
  34. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  35. GRB000926: Optical observations
  36. GRB 000926 HST/Chandra TOO Status
  37. GRB000926, radio observations
  38. GRB 000926: Optical candidate
  39. GRB000911: Sub-millimeter observations
  40. GRB000911, Radio and Optical observations
  41. GRB000911, Radio observations
  42. GRB000911: Optical observations
  43. GRB 000830: Optical observations
  44. GRB000830: Optical observations
  45. GRB000830, TNG B-band observations
  46. GRB000830: Optical observations
  47. GRB000210, Optical observations
  48. "Snapshot" afterglow IDs and GRB 000830
  49. GRB000830: Optical observations
  50. HST/STIS observations of the host galaxy of GRB 980329
  51. HST/STIS observations of the chaotic environment of GRB 980613
  52. SGR 1806-20 burst activity
  53. GRB000812, TNG R-band observations
  54. GRB000801 & GRB000730, Gamma Ray Observations
  55. GRB000730, Gamma Ray Observations
  56. GRB000812, Radio observations
  57. GRB000801, Gamma Ray Observations
  58. GRB000801, VLT-Antu R-band observations
  59. GRB000301C, UBVI optical observations
  60. GRB000801, Radio Observations
  61. GRB 991208 Host Galaxy Imaging
  62. GRB 990510: Possible detection of a host galaxy
  63. GRB 990510 Host Galaxy Discovery
  64. GRB 000727, optical observations
  65. GRB 990705, HST/STIS observations of the host galaxy
  66. GRB 990712: Late time HST/STIS Observations
  67. GRB 991216, HST/STIS observations
  68. GRB000620, Radio Observations
  69. GRB981226, HST/STIS observations of the host galaxy
  70. GRB000630, optical observations
  71. GRB 000630: Detection of the Optical Afterglow
  72. GRB000630, Optical Observations
  73. GRB000630, optical observations
  74. GRB000630, optical observations
  75. GRB000630, optical observations
  76. GRB000630, optical observations
  77. GRB000630: Optical observations
  78. GRB000630, Radio Observations
  79. possible optical counterpart of GRB 000630
  80. GRB 000623, optical observations
  81. GRB 000620, optical observations
  82. GRB000418, HST/STIS Observations
  83. GRB990123: Late-time HST/STIS observations of the host
  84. GRB 990506, HST/STIS Observations of the Host Galaxy
  85. GRB 000620: J-band observations
  86. GRB000620, optical observations
  87. GRB000615: H-band observations
  88. GRB990308, HST/STIS observations of the host galaxy
  89. GRB000620 - Optical observations
  90. GRB000620 Optical observations
  91. GRB000615, Radio observations
  92. GRB000607, optical observations
  93. GRB 000615: NIR further observations
  94. GRB990123, HST/STIS observations of the host galaxy
  95. GRB000616 optical observations
  96. GRB 000615, near-infrared observations
  97. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  98. GRB000615, further R-band photometry
  99. GRB 000615: NIR observations
  100. GRB000615, R-band photometry

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Download all Circulars as a .tar.gz archive:
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