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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"

43626 results found.

  1. GRB000301C, UBVI optical observations
  2. GRB000801, Radio Observations
  3. GRB 991208 Host Galaxy Imaging
  4. IPN localization of GRB000801
  5. IPN localization of GRB000730B
  6. IPN localization of GRB000730B
  7. IPN localization of GRB000730
  8. GRB 990510: Possible detection of a host galaxy
  9. GRB 990510 Host Galaxy Discovery
  10. GRB 000727, optical observations
  11. IPN localization of GRB000727
  12. GRB 990705, HST/STIS observations of the host galaxy
  13. GRB 990712: Late time HST/STIS Observations
  14. GRB 991216, HST/STIS observations
  15. GRB000620, Radio Observations
  16. GRB981226, HST/STIS observations of the host galaxy
  17. GRB000630, optical observations
  18. GRB 000630: Detection of the Optical Afterglow
  19. GRB000630, Revised BVRI Field Photometry
  20. GRB000630, Optical Observations
  21. GRB000630, optical observations
  22. GRB000630, optical observations
  23. GRB000630, BVRI Field Photometry
  24. GRB000630, optical observations
  25. GRB000630, optical observations
  26. GRB000630: Optical observations
  27. GRB000630, Radio Observations
  28. possible optical counterpart of GRB 000630
  29. IPN triangulation of GRB000630
  30. GRB 000623, optical observations
  31. GRB 000620, optical observations
  32. GRB000418, HST/STIS Observations
  33. GRB990123: Late-time HST/STIS observations of the host
  34. GRB 990506, HST/STIS Observations of the Host Galaxy
  35. GRB000623
  36. GRB 000620: J-band observations
  37. GRB000620, optical observations
  38. GRB000615: H-band observations
  39. GRB990308, HST/STIS observations of the host galaxy
  40. GRB000620 Optical observations
  41. IPN annulus for GRB000620
  42. GRB000620: BeppoSAX WFC and GRBM detection
  43. GRB000615, Radio observations
  44. GRB000607, optical observations
  45. GRB 000615: NIR further observations
  46. GRB000620: refined BeppoSAX/WFC coordinates
  47. BeppoSAX ALERT: GRB000620
  48. GRB000620: BeppoSAX Alert
  49. GRB990123, HST/STIS observations of the host galaxy
  50. GRB000616 optical observations
  51. GRB 000615, near-infrared observations
  52. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  53. GRB000615, further R-band photometry
  54. GRB 000615: NIR observations
  55. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  56. GRB000615: BeppoSAX refined coordinates
  57. GRB980425, HST/STIS observations of the host galaxy
  58. GRB000615: BeppoSAX GRB Alert
  59. The Hosts of GRB 980703 and GRB 971214
  60. GRB 000301C: Further Late-Time HST/STIS observations
  61. GRB000528: follow-up X-ray measurements and update of IPN annulus
  62. Optical Follow-up of GRB000529 Error Box
  63. GRB980519, HST/STIS observations of the host galaxy
  64. GRB000607, Radio Observations
  65. BeppoSAX X-ray transient/possible GRB000608
  66. GRB000604 optical non-detection
  67. GRB000604 - Optical observations
  68. GRB000607, A SHORT, HARD BURST
  69. GRB000604, optical observations
  70. GRB000528, optical observations at ESO
  71. GRB 000604 optical observations
  72. GRB 000418: Detection of the Host Galaxy
  73. GRB000604, optical observations, comparison with DPOSS
  74. GRB000604 [IPN Position]
  75. GRB000528, Radio Observations
  76. X-ray Afterglow of GRB 000529
  77. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  78. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  79. GRB000529: Optical Observations
  80. IPN localization and time history of GRB000528
  81. New IPN localization of GRB000529
  82. GRB000519: Optical observations
  83. GRB000529: BeppoSAX WFC position
  84. GRB000528: BeppoSAX GRBM observations
  85. GRB 000528 Optical Observations
  86. GRB000519, BVRI field photometry
  87. IPN triangulation of GRB000519
  88. IPN triangulation of GRB000516
  89. Re: GRB000508B : Optical observations
  90. GRB 000418, Optical observation
  91. GRB000508B, optical photometry
  92. GRB000508B, BVR field photometry
  93. Possible GRB-related phenomenon
  94. RXTE/ASM and IPN localization of GRB 000508B
  95. GRB000424, UBVRI field photometry
  96. GRB 000424 Optical Observations
  97. GRB000418, UBVRI field photometry update
  98. The redshift of GRB 000418
  99. GRB000424, optical observations
  100. GRB 000429, optical observation

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