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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"
  1. IPN localization of GRB000820
  2. SGR 1806-20 burst activity
  3. GRB000812, TNG R-band observations
  4. GRB000801 & GRB000730, Gamma Ray Observations
  5. GRB000730, Gamma Ray Observations
  6. GRB000812, Radio observations
  7. IPN localization of GRB000812
  8. IPN localization of GRB000811
  9. GRB000801, Gamma Ray Observations
  10. GRB000801, VLT-Antu R-band observations
  11. GRB000301C, UBVI optical observations
  12. GRB000801, Radio Observations
  13. GRB 991208 Host Galaxy Imaging
  14. Updated IPN coordinates for GRB000801
  15. IPN localization of GRB000801
  16. IPN localization of GRB000801
  17. IPN localization of GRB000730B
  18. IPN localization of GRB000730B
  19. IPN localization of GRB000730
  20. GRB 990510: Possible detection of a host galaxy
  21. GRB 990510 Host Galaxy Discovery
  22. GRB 000727, optical observations
  23. IPN localization of GRB000727
  24. GRB 990705, HST/STIS observations of the host galaxy
  25. GRB 990712: Late time HST/STIS Observations
  26. GRB 991216, HST/STIS observations
  27. GRB000620, Radio Observations
  28. GRB981226, HST/STIS observations of the host galaxy
  29. GRB000630, optical observations
  30. GRB 000630: Detection of the Optical Afterglow
  31. GRB000630, Revised BVRI Field Photometry
  32. GRB000630, Optical Observations
  33. GRB000630, optical observations
  34. GRB000630, optical observations
  35. GRB000630, BVRI Field Photometry
  36. GRB000630, optical observations
  37. GRB000630, optical observations
  38. GRB000630: Optical observations
  39. GRB000630, Radio Observations
  40. possible optical counterpart of GRB 000630
  41. IPN triangulation of GRB000630
  42. GRB 000623, optical observations
  43. GRB 000620, optical observations
  44. GRB000418, HST/STIS Observations
  45. GRB990123: Late-time HST/STIS observations of the host
  46. GRB 990506, HST/STIS Observations of the Host Galaxy
  47. GRB000623
  48. GRB 000620: J-band observations
  49. GRB000620, optical observations
  50. GRB000615: H-band observations
  51. GRB990308, HST/STIS observations of the host galaxy
  52. GRB000620 - Optical observations
  53. GRB000620 Optical observations
  54. IPN annulus for GRB000620
  55. GRB000620: BeppoSAX WFC and GRBM detection
  56. GRB000615, Radio observations
  57. GRB000607, optical observations
  58. GRB 000615: NIR further observations
  59. GRB000620: refined BeppoSAX/WFC coordinates
  60. BeppoSAX ALERT: GRB000620
  61. GRB000620: BeppoSAX Alert
  62. GRB990123, HST/STIS observations of the host galaxy
  63. GRB000616 optical observations
  64. GRB 000615, near-infrared observations
  65. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  66. GRB000616 [IPN Position]
  67. GRB000615B [IPN Position]
  68. GRB000615, further R-band photometry
  69. GRB 000615: NIR observations
  70. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  71. GRB000615, R-band photometry
  72. GRB000615: BeppoSAX refined coordinates
  73. GRB980425, HST/STIS observations of the host galaxy
  74. GRB000615: BeppoSAX GRB Alert
  75. The Hosts of GRB 980703 and GRB 971214
  76. GRB 000301C: Further Late-Time HST/STIS observations
  77. GRB000528: follow-up X-ray measurements and update of IPN annulus
  78. Optical Follow-up of GRB000529 Error Box
  79. GRB980519, HST/STIS observations of the host galaxy
  80. GRB000607, Radio Observations
  81. BeppoSAX X-ray transient/possible GRB000608
  82. GRB000604 optical non-detection
  83. GRB000604 - Optical observations
  84. GRB000607, A SHORT, HARD BURST
  85. GRB000604, optical observations
  86. GRB000528, optical observations at ESO
  87. GRB 000604 optical observations
  88. GRB 000418: Detection of the Host Galaxy
  89. GRB000604, optical observations, comparison with DPOSS
  90. GRB000604 [IPN Position]
  91. GRB000528, Radio Observations
  92. X-ray Afterglow of GRB 000529
  93. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  94. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  95. GRB000529: Optical Observations
  96. IPN localization and time history of GRB000528
  97. New IPN localization of GRB000529
  98. GRB000519: Optical observations
  99. IPN localization of GRB000529
  100. GRB 000528 - WFC measurements

Advanced

Download all Circulars as a .tar.gz archive:
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