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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. GRB 990510: Possible detection of a host galaxy
  2. GRB 990510 Host Galaxy Discovery
  3. GRB 000727, optical observations
  4. IPN localization of GRB000727
  5. GRB 990705, HST/STIS observations of the host galaxy
  6. GRB 990712: Late time HST/STIS Observations
  7. GRB 991216, HST/STIS observations
  8. GRB000620, Radio Observations
  9. GRB981226, HST/STIS observations of the host galaxy
  10. GRB000630, optical observations
  11. GRB 000630: Detection of the Optical Afterglow
  12. GRB000630, Revised BVRI Field Photometry
  13. GRB000630, Optical Observations
  14. GRB000630, optical observations
  15. GRB000630, optical observations
  16. GRB000630, BVRI Field Photometry
  17. GRB000630, optical observations
  18. GRB000630, optical observations
  19. GRB000630: Optical observations
  20. GRB000630, Radio Observations
  21. possible optical counterpart of GRB 000630
  22. IPN triangulation of GRB000630
  23. GRB 000623, optical observations
  24. GRB 000620, optical observations
  25. GRB000418, HST/STIS Observations
  26. GRB990123: Late-time HST/STIS observations of the host
  27. GRB 990506, HST/STIS Observations of the Host Galaxy
  28. GRB000623
  29. GRB 000620: J-band observations
  30. GRB000620, optical observations
  31. GRB000615: H-band observations
  32. GRB990308, HST/STIS observations of the host galaxy
  33. GRB000620 - Optical observations
  34. GRB000620 Optical observations
  35. IPN annulus for GRB000620
  36. GRB000620: BeppoSAX WFC and GRBM detection
  37. GRB000615, Radio observations
  38. GRB000607, optical observations
  39. GRB 000615: NIR further observations
  40. GRB000620: refined BeppoSAX/WFC coordinates
  41. BeppoSAX ALERT: GRB000620
  42. GRB000620: BeppoSAX Alert
  43. GRB990123, HST/STIS observations of the host galaxy
  44. GRB000616 optical observations
  45. GRB 000615, near-infrared observations
  46. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  47. GRB000616 [IPN Position]
  48. GRB000615B [IPN Position]
  49. GRB000615, further R-band photometry
  50. GRB 000615: NIR observations
  51. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  52. GRB000615, R-band photometry
  53. GRB000615: BeppoSAX refined coordinates
  54. GRB980425, HST/STIS observations of the host galaxy
  55. GRB000615: BeppoSAX GRB Alert
  56. The Hosts of GRB 980703 and GRB 971214
  57. GRB 000301C: Further Late-Time HST/STIS observations
  58. GRB000528: follow-up X-ray measurements and update of IPN annulus
  59. Optical Follow-up of GRB000529 Error Box
  60. GRB980519, HST/STIS observations of the host galaxy
  61. GRB000607, Radio Observations
  62. BeppoSAX X-ray transient/possible GRB000608
  63. GRB000604 optical non-detection
  64. GRB000604 - Optical observations
  65. GRB000607, A SHORT, HARD BURST
  66. GRB000604, optical observations
  67. GRB000528, optical observations at ESO
  68. GRB 000604 optical observations
  69. GRB 000418: Detection of the Host Galaxy
  70. GRB000604, optical observations, comparison with DPOSS
  71. GRB000604 [IPN Position]
  72. GRB000528, Radio Observations
  73. X-ray Afterglow of GRB 000529
  74. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  75. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  76. GRB000529: Optical Observations
  77. IPN localization and time history of GRB000528
  78. New IPN localization of GRB000529
  79. GRB000519: Optical observations
  80. IPN localization of GRB000529
  81. GRB 000528 - WFC measurements
  82. GRB000529: BeppoSAX WFC position
  83. GRB000528: BeppoSAX GRBM observations
  84. GRB 000528 Optical Observations
  85. GRB000519, BVRI field photometry
  86. IPN triangulation of GRB000519
  87. IPN triangulation of GRB000516
  88. Re: GRB000508B : Optical observations
  89. GRB 000418, Optical observation
  90. GRB000508B, optical photometry
  91. GRB000508B, BVR field photometry
  92. Possible GRB-related phenomenon
  93. RXTE/ASM and IPN localization of GRB 000508B
  94. GRB000424, UBVRI field photometry
  95. GRB 000424 Optical Observations
  96. GRB000418, UBVRI field photometry update
  97. The redshift of GRB 000418
  98. GRB000424, optical observations
  99. GRB 000429, optical observation
  100. GRB 000429, UBVRI field photometry

Advanced

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