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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"

15556 results found.

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

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