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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').

19109 results found.

  1. IPN triangulation of GRB001025
  2. GRB001007: Optical observations
  3. ASM Localization of GRB 001025
  4. GRB001007, Radio observations
  5. IPN TRIANGULATION OF GRB001020
  6. GRB001018, Gamma Ray Observations
  7. V,R,I band observations of GRB000926
  8. The Likely Optical/Infrared Afterglow of GRB 001011
  9. HETE positions added to GCN
  10. BeppoSAX ALERT: GRB001011
  11. GRB000926 - Amateur Optical Observations
  12. CONCAM null result on GRB001005
  13. IPN triangulation of GRB001007
  14. IPN triangulation of GRB001005
  15. GRB 000926 Chandra Observation
  16. IPN triangulation of GRB 001004
  17. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  18. GRB000926 - Optical observations
  19. GRB000926 - Optical observations
  20. GRB 000926, Optical Observations
  21. GRB000926 K'-band Observation
  22. J and K band observations of GRB 000926
  23. GRB 000926, optical observation by Oksanen (vsnet-grb)
  24. CONCAM crude optical limits before and after GRB000926
  25. Spectroscopic Redshift of GRB 000926
  26. GRB 000926: Optical candidate
  27. Optical candidate for GRB000926
  28. IPN triangulation of GRB000926
  29. GRB 000911, BVRI field photometry
  30. IPN triangulation of GRB000925
  31. GRB000911: Optical Transient
  32. GRB000911, Radio and Optical observations
  33. GRB000911: Optical observations
  34. IPN triangulation of GRB000911
  35. GRB000830, BVRI field photometry
  36. Chandra Position of GRB000210
  37. IPN localization of GRB000820
  38. SGR 1806-20 burst activity
  39. GRB000730, Gamma Ray Observations
  40. IPN localization of GRB000812
  41. IPN localization of GRB000811
  42. GRB000801, Gamma Ray Observations
  43. GRB000801, VLT-Antu R-band observations
  44. GRB 991208 Host Galaxy Imaging
  45. IPN localization of GRB000801
  46. IPN localization of GRB000730B
  47. GRB 990510: Possible detection of a host galaxy
  48. GRB 990510 Host Galaxy Discovery
  49. GRB 990705, HST/STIS observations of the host galaxy
  50. GRB 990712: Late time HST/STIS Observations
  51. GRB 991216, HST/STIS observations
  52. GRB000630, optical observations
  53. GRB000630, Revised BVRI Field Photometry
  54. GRB000630, Optical Observations
  55. GRB000630, optical observations
  56. GRB000630, optical observations
  57. GRB000630, BVRI Field Photometry
  58. GRB000630, optical observations
  59. GRB000630: Optical observations
  60. possible optical counterpart of GRB 000630
  61. IPN triangulation of GRB000630
  62. GRB 000620, optical observations
  63. GRB000418, HST/STIS Observations
  64. GRB990123: Late-time HST/STIS observations of the host
  65. GRB000623
  66. GRB000620, optical observations
  67. GRB000615: H-band observations
  68. GRB000620 - Optical observations
  69. GRB000620 Optical observations
  70. GRB000620: BeppoSAX WFC and GRBM detection
  71. GRB000615, Radio observations
  72. GRB000607, optical observations
  73. GRB 000615: NIR further observations
  74. BeppoSAX ALERT: GRB000620
  75. GRB000620: BeppoSAX Alert
  76. GRB000616 optical observations
  77. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  78. GRB000615, further R-band photometry
  79. GRB 000615: NIR observations
  80. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  81. GRB000615, R-band photometry
  82. GRB000615: BeppoSAX GRB Alert
  83. The Hosts of GRB 980703 and GRB 971214
  84. GRB 000301C: Further Late-Time HST/STIS observations
  85. GRB000528: follow-up X-ray measurements and update of IPN annulus
  86. GRB000607, Radio Observations
  87. GRB000604 - Optical observations
  88. GRB000604, optical observations
  89. GRB000528, optical observations at ESO
  90. GRB 000418: Detection of the Host Galaxy
  91. GRB000604, optical observations, comparison with DPOSS
  92. GRB000604 [IPN Position]
  93. GRB000528, Radio Observations
  94. X-ray Afterglow of GRB 000529
  95. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  96. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  97. GRB000519: Optical observations
  98. GRB 000528 - WFC measurements
  99. GRB000528: BeppoSAX GRBM observations
  100. GRB000519, BVRI field photometry

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