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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"

16157 results found.

  1. GRB000926, radio observations
  2. GRB 000926: Optical candidate
  3. Optical candidate for GRB000926
  4. GRB 000911, BVRI field photometry
  5. GRB000911: Sub-millimeter observations
  6. GRB000911: Optical Transient
  7. GRB000911, Radio and Optical observations
  8. GRB000911: Optical observations
  9. GRB 000830: Optical observations
  10. GRB000830: Optical observations
  11. GRB000830, TNG B-band observations
  12. GRB000830, BVRI field photometry
  13. GRB000830: Optical observations
  14. GRB000210, Optical observations
  15. Chandra Position of GRB000210
  16. "Snapshot" afterglow IDs and GRB 000830
  17. GRB000830: Optical observations
  18. HST/STIS observations of the host galaxy of GRB 980329
  19. HST/STIS observations of the chaotic environment of GRB 980613
  20. GRB000812, TNG R-band observations
  21. GRB000801, VLT-Antu R-band observations
  22. GRB000301C, UBVI optical observations
  23. GRB 000727, optical observations
  24. GRB 990712: Late time HST/STIS Observations
  25. GRB000630, optical observations
  26. GRB 000630: Detection of the Optical Afterglow
  27. GRB000630, Optical Observations
  28. GRB000630, optical observations
  29. GRB000630, optical observations
  30. GRB000630, BVRI Field Photometry
  31. GRB000630, optical observations
  32. GRB000630, optical observations
  33. GRB000630: Optical observations
  34. GRB000630, Radio Observations
  35. possible optical counterpart of GRB 000630
  36. GRB 000623, optical observations
  37. GRB 000620, optical observations
  38. GRB000418, HST/STIS Observations
  39. GRB 990506, HST/STIS Observations of the Host Galaxy
  40. GRB000620, optical observations
  41. GRB990308, HST/STIS observations of the host galaxy
  42. GRB000620 - Optical observations
  43. GRB000620 Optical observations
  44. GRB000607, optical observations
  45. GRB990123, HST/STIS observations of the host galaxy
  46. GRB000616 optical observations
  47. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  48. GRB000615, further R-band photometry
  49. The Hosts of GRB 980703 and GRB 971214
  50. GRB 000301C: Further Late-Time HST/STIS observations
  51. Optical Follow-up of GRB000529 Error Box
  52. GRB000604 optical non-detection
  53. GRB000604 - Optical observations
  54. GRB000604, optical observations
  55. GRB000528, optical observations at ESO
  56. GRB 000604 optical observations
  57. GRB 000418: Detection of the Host Galaxy
  58. GRB000604, optical observations, comparison with DPOSS
  59. GRB000529: Optical Observations
  60. GRB000519: Optical observations
  61. GRB 000528 Optical Observations
  62. GRB000519, BVRI field photometry
  63. Re: GRB000508B : Optical observations
  64. GRB 000418, Optical observation
  65. GRB000508B, optical photometry
  66. GRB000508B, BVR field photometry
  67. Possible GRB-related phenomenon
  68. GRB000424, UBVRI field photometry
  69. GRB 000424 Optical Observations
  70. GRB000418, UBVRI field photometry update
  71. GRB000424, optical observations
  72. GRB 000429, optical observation
  73. GRB 000429, UBVRI field photometry
  74. GRB000418, Radio detection
  75. GRB 000418, Optical Observation
  76. GRB 000418, optical observation
  77. GRB000424 Optical Observations
  78. GRB 000418, Optical Observation
  79. GRB000424, optical observations
  80. GRB000424, optical observations
  81. GRB 000424, Optical Observations
  82. GRB 000418, Optical Observation
  83. GRB000416 Optical Observations
  84. GRB000416 BRJK observations
  85. GRB 000408, optical observations
  86. GRB 991208, UBVRI field photometry
  87. GRB000301c results
  88. GRB000408: Optical CCD Observations from MIRO
  89. GRB000408, lotis optical observations
  90. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  91. GRB000326 Optical Observations
  92. GRB000301C - R magnitude lower limit
  93. GRB 000323, optical observations
  94. GRB 000326: Optical Observations
  95. GRB 000307 optical observations
  96. GRB000313, Radio observations
  97. GRB 000313 - optical transient in the BATSE error box
  98. GRB000301C - B and R photometry
  99. GRB000301C - R photometry
  100. GRB 000307, Optical Observations

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Download all Circulars as a .tar.gz archive (updated once a day):
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