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

Advanced

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