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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"

20502 results found.

  1. The Likely Optical/Infrared Afterglow of GRB 001011
  2. HETE positions added to GCN
  3. BeppoSAX ALERT: GRB001011
  4. GRB000926 - Amateur Optical Observations
  5. CONCAM null result on GRB001005
  6. IPN triangulation of GRB001007
  7. IPN triangulation of GRB001005
  8. GRB 000926 Chandra Observation
  9. IPN triangulation of GRB 001004
  10. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  11. GRB000926 - Optical observations
  12. GRB000926 - Optical observations
  13. GRB 000926, Optical Observations
  14. GRB000926 K'-band Observation
  15. J and K band observations of GRB 000926
  16. GRB 000926, optical observation by Oksanen (vsnet-grb)
  17. CONCAM crude optical limits before and after GRB000926
  18. Spectroscopic Redshift of GRB 000926
  19. GRB 000926: Optical candidate
  20. Optical candidate for GRB000926
  21. IPN triangulation of GRB000926
  22. GRB 000911, BVRI field photometry
  23. IPN triangulation of GRB000925
  24. GRB000911: Optical Transient
  25. GRB000911, Radio and Optical observations
  26. GRB000911: Optical observations
  27. IPN triangulation of GRB000911
  28. GRB000830, BVRI field photometry
  29. Chandra Position of GRB000210
  30. IPN localization of GRB000820
  31. SGR 1806-20 burst activity
  32. GRB000730, Gamma Ray Observations
  33. IPN localization of GRB000812
  34. IPN localization of GRB000811
  35. GRB000801, Gamma Ray Observations
  36. GRB000801, VLT-Antu R-band observations
  37. GRB 991208 Host Galaxy Imaging
  38. IPN localization of GRB000801
  39. IPN localization of GRB000730B
  40. GRB 990510: Possible detection of a host galaxy
  41. GRB 990510 Host Galaxy Discovery
  42. GRB 990705, HST/STIS observations of the host galaxy
  43. GRB 990712: Late time HST/STIS Observations
  44. GRB 991216, HST/STIS observations
  45. GRB000630, optical observations
  46. GRB000630, Revised BVRI Field Photometry
  47. GRB000630, Optical Observations
  48. GRB000630, optical observations
  49. GRB000630, optical observations
  50. GRB000630, BVRI Field Photometry
  51. GRB000630, optical observations
  52. GRB000630: Optical observations
  53. possible optical counterpart of GRB 000630
  54. IPN triangulation of GRB000630
  55. GRB 000620, optical observations
  56. GRB000418, HST/STIS Observations
  57. GRB990123: Late-time HST/STIS observations of the host
  58. GRB000623
  59. GRB000620, optical observations
  60. GRB000615: H-band observations
  61. GRB000620 - Optical observations
  62. GRB000620 Optical observations
  63. GRB000620: BeppoSAX WFC and GRBM detection
  64. GRB000615, Radio observations
  65. GRB000607, optical observations
  66. GRB 000615: NIR further observations
  67. BeppoSAX ALERT: GRB000620
  68. GRB000620: BeppoSAX Alert
  69. GRB000616 optical observations
  70. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  71. GRB000615, further R-band photometry
  72. GRB 000615: NIR observations
  73. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  74. GRB000615, R-band photometry
  75. GRB000615: BeppoSAX GRB Alert
  76. The Hosts of GRB 980703 and GRB 971214
  77. GRB 000301C: Further Late-Time HST/STIS observations
  78. GRB000528: follow-up X-ray measurements and update of IPN annulus
  79. GRB000607, Radio Observations
  80. GRB000604 - Optical observations
  81. GRB000604, optical observations
  82. GRB000528, optical observations at ESO
  83. GRB 000418: Detection of the Host Galaxy
  84. GRB000604, optical observations, comparison with DPOSS
  85. GRB000604 [IPN Position]
  86. GRB000528, Radio Observations
  87. X-ray Afterglow of GRB 000529
  88. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  89. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  90. GRB000519: Optical observations
  91. GRB 000528 - WFC measurements
  92. GRB000528: BeppoSAX GRBM observations
  93. GRB000519, BVRI field photometry
  94. IPN triangulation of GRB000519
  95. GRB000508B, optical photometry
  96. GRB000508B, BVR field photometry
  97. Possible GRB-related phenomenon
  98. RXTE/ASM and IPN localization of GRB 000508B
  99. GRB000424, UBVRI field photometry
  100. GRB000418, UBVRI field photometry update

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Download all Circulars as a .tar.gz archive:
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