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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"

22053 results found.

  1. GRB000911: Optical observations
  2. IPN triangulation of GRB000911
  3. IPN triangulation of GRB000910
  4. GRB 000830: Optical observations
  5. GRB000830: Optical observations
  6. GRB000830, TNG B-band observations
  7. GRB000830: Optical observations
  8. GRB000210, Optical observations
  9. "Snapshot" afterglow IDs and GRB 000830
  10. GRB000830: Optical observations
  11. IPN triangulation of GRB000830
  12. HST/STIS observations of the host galaxy of GRB 980329
  13. HST/STIS observations of the chaotic environment of GRB 980613
  14. IPN localization of GRB000820
  15. SGR 1806-20 burst activity
  16. GRB000812, TNG R-band observations
  17. GRB000801 & GRB000730, Gamma Ray Observations
  18. GRB000730, Gamma Ray Observations
  19. GRB000812, Radio observations
  20. IPN localization of GRB000812
  21. IPN localization of GRB000811
  22. GRB000801, Gamma Ray Observations
  23. GRB000801, VLT-Antu R-band observations
  24. GRB000301C, UBVI optical observations
  25. GRB000801, Radio Observations
  26. Updated IPN coordinates for GRB000801
  27. IPN localization of GRB000801
  28. IPN localization of GRB000730B
  29. IPN localization of GRB000730B
  30. IPN localization of GRB000730
  31. GRB 990510: Possible detection of a host galaxy
  32. GRB 000727, optical observations
  33. IPN localization of GRB000727
  34. GRB 990705, HST/STIS observations of the host galaxy
  35. GRB 990712: Late time HST/STIS Observations
  36. GRB 991216, HST/STIS observations
  37. GRB000620, Radio Observations
  38. GRB981226, HST/STIS observations of the host galaxy
  39. GRB000630, optical observations
  40. GRB 000630: Detection of the Optical Afterglow
  41. GRB000630, Optical Observations
  42. GRB000630, optical observations
  43. GRB000630, optical observations
  44. GRB000630, optical observations
  45. GRB000630, optical observations
  46. GRB000630: Optical observations
  47. GRB000630, Radio Observations
  48. possible optical counterpart of GRB 000630
  49. IPN triangulation of GRB000630
  50. GRB 000623, optical observations
  51. GRB 000620, optical observations
  52. GRB000418, HST/STIS Observations
  53. GRB990123: Late-time HST/STIS observations of the host
  54. GRB 990506, HST/STIS Observations of the Host Galaxy
  55. GRB000623
  56. GRB 000620: J-band observations
  57. GRB000620, optical observations
  58. GRB000615: H-band observations
  59. GRB990308, HST/STIS observations of the host galaxy
  60. GRB000620 - Optical observations
  61. GRB000620 Optical observations
  62. GRB000615, Radio observations
  63. GRB000607, optical observations
  64. GRB 000615: NIR further observations
  65. GRB990123, HST/STIS observations of the host galaxy
  66. GRB000616 optical observations
  67. GRB 000615, near-infrared observations
  68. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  69. GRB000616 [IPN Position]
  70. GRB000615B [IPN Position]
  71. GRB000615, further R-band photometry
  72. GRB 000615: NIR observations
  73. GRB000615, R-band photometry
  74. GRB980425, HST/STIS observations of the host galaxy
  75. GRB 000301C: Further Late-Time HST/STIS observations
  76. GRB980519, HST/STIS observations of the host galaxy
  77. GRB000607, Radio Observations
  78. GRB000604 - Optical observations
  79. GRB000607, A SHORT, HARD BURST
  80. GRB000604, optical observations
  81. GRB000528, optical observations at ESO
  82. GRB 000604 optical observations
  83. GRB 000418: Detection of the Host Galaxy
  84. GRB000604, optical observations, comparison with DPOSS
  85. GRB000604 [IPN Position]
  86. GRB000528, Radio Observations
  87. GRB000529: Optical Observations
  88. New IPN localization of GRB000529
  89. GRB000519: Optical observations
  90. IPN localization of GRB000529
  91. GRB000528: BeppoSAX GRBM observations
  92. GRB 000528 Optical Observations
  93. IPN triangulation of GRB000519
  94. IPN triangulation of GRB000516
  95. Re: GRB000508B : Optical observations
  96. GRB000508B, optical photometry
  97. Possible GRB-related phenomenon
  98. GRB 000424 Optical Observations
  99. The redshift of GRB 000418
  100. GRB000424, optical observations

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