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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"

16156 results found.

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

Advanced

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