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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').
  1. GRB000830, BVRI field photometry
  2. GRB000830: Optical observations
  3. GRB000210, Optical observations
  4. Chandra Position of GRB000210
  5. "Snapshot" afterglow IDs and GRB 000830
  6. GRB000830: Optical observations
  7. IPN triangulation of GRB000830
  8. HST/STIS observations of the host galaxy of GRB 980329
  9. HST/STIS observations of the chaotic environment of GRB 980613
  10. IPN localization of GRB000820
  11. SGR 1806-20 burst activity
  12. GRB000812, TNG R-band observations
  13. GRB000801 & GRB000730, Gamma Ray Observations
  14. GRB000730, Gamma Ray Observations
  15. GRB000812, Radio observations
  16. IPN localization of GRB000812
  17. IPN localization of GRB000811
  18. GRB000801, Gamma Ray Observations
  19. GRB000801, VLT-Antu R-band observations
  20. GRB000301C, UBVI optical observations
  21. GRB000801, Radio Observations
  22. GRB 991208 Host Galaxy Imaging
  23. Updated IPN coordinates for GRB000801
  24. IPN localization of GRB000801
  25. IPN localization of GRB000801
  26. IPN localization of GRB000730B
  27. IPN localization of GRB000730B
  28. IPN localization of GRB000730
  29. GRB 990510: Possible detection of a host galaxy
  30. GRB 990510 Host Galaxy Discovery
  31. GRB 000727, optical observations
  32. IPN localization of GRB000727
  33. GRB 990705, HST/STIS observations of the host galaxy
  34. GRB 990712: Late time HST/STIS Observations
  35. GRB 991216, HST/STIS observations
  36. GRB000620, Radio Observations
  37. GRB981226, HST/STIS observations of the host galaxy
  38. GRB000630, optical observations
  39. GRB 000630: Detection of the Optical Afterglow
  40. GRB000630, Revised BVRI Field Photometry
  41. GRB000630, Optical Observations
  42. GRB000630, optical observations
  43. GRB000630, optical observations
  44. GRB000630, BVRI Field Photometry
  45. GRB000630, optical observations
  46. GRB000630, optical observations
  47. GRB000630: Optical observations
  48. GRB000630, Radio Observations
  49. possible optical counterpart of GRB 000630
  50. IPN triangulation of GRB000630
  51. GRB 000623, optical observations
  52. GRB 000620, optical observations
  53. GRB000418, HST/STIS Observations
  54. GRB990123: Late-time HST/STIS observations of the host
  55. GRB 990506, HST/STIS Observations of the Host Galaxy
  56. GRB000623
  57. GRB 000620: J-band observations
  58. GRB000620, optical observations
  59. GRB000615: H-band observations
  60. GRB990308, HST/STIS observations of the host galaxy
  61. GRB000620 - Optical observations
  62. GRB000620 Optical observations
  63. IPN annulus for GRB000620
  64. GRB000620: BeppoSAX WFC and GRBM detection
  65. GRB000615, Radio observations
  66. GRB000607, optical observations
  67. GRB 000615: NIR further observations
  68. GRB000620: refined BeppoSAX/WFC coordinates
  69. BeppoSAX ALERT: GRB000620
  70. GRB000620: BeppoSAX Alert
  71. GRB990123, HST/STIS observations of the host galaxy
  72. GRB000616 optical observations
  73. GRB 000615, near-infrared observations
  74. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  75. GRB000616 [IPN Position]
  76. GRB000615B [IPN Position]
  77. GRB000615, further R-band photometry
  78. GRB 000615: NIR observations
  79. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  80. GRB000615, R-band photometry
  81. GRB000615: BeppoSAX refined coordinates
  82. GRB980425, HST/STIS observations of the host galaxy
  83. GRB000615: BeppoSAX GRB Alert
  84. The Hosts of GRB 980703 and GRB 971214
  85. GRB 000301C: Further Late-Time HST/STIS observations
  86. GRB000528: follow-up X-ray measurements and update of IPN annulus
  87. Optical Follow-up of GRB000529 Error Box
  88. GRB980519, HST/STIS observations of the host galaxy
  89. GRB000607, Radio Observations
  90. BeppoSAX X-ray transient/possible GRB000608
  91. GRB000604 optical non-detection
  92. GRB000604 - Optical observations
  93. GRB000607, A SHORT, HARD BURST
  94. GRB000604, optical observations
  95. GRB000528, optical observations at ESO
  96. GRB 000604 optical observations
  97. GRB 000418: Detection of the Host Galaxy
  98. GRB000604, optical observations, comparison with DPOSS
  99. GRB000604 [IPN Position]
  100. GRB000528, Radio Observations

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