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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"

21207 results found.

  1. ASM Localization of GRB 001025
  2. GRB001007, Radio observations
  3. IPN TRIANGULATION OF GRB001020
  4. GRB001018, Gamma Ray Observations
  5. V,R,I band observations of GRB000926
  6. The Likely Optical/Infrared Afterglow of GRB 001011
  7. HETE positions added to GCN
  8. BeppoSAX ALERT: GRB001011
  9. GRB000926 - Amateur Optical Observations
  10. CONCAM null result on GRB001005
  11. IPN triangulation of GRB001007
  12. IPN triangulation of GRB001005
  13. GRB 000926 Chandra Observation
  14. IPN triangulation of GRB 001004
  15. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  16. GRB000926 - Optical observations
  17. GRB000926 - Optical observations
  18. GRB 000926, Optical Observations
  19. GRB000926 K'-band Observation
  20. J and K band observations of GRB 000926
  21. GRB 000926, optical observation by Oksanen (vsnet-grb)
  22. CONCAM crude optical limits before and after GRB000926
  23. Spectroscopic Redshift of GRB 000926
  24. GRB 000926: Optical candidate
  25. Optical candidate for GRB000926
  26. IPN triangulation of GRB000926
  27. GRB 000911, BVRI field photometry
  28. IPN triangulation of GRB000925
  29. GRB000911: Optical Transient
  30. GRB000911, Radio and Optical observations
  31. GRB000911: Optical observations
  32. IPN triangulation of GRB000911
  33. GRB000830, BVRI field photometry
  34. Chandra Position of GRB000210
  35. IPN localization of GRB000820
  36. SGR 1806-20 burst activity
  37. GRB000730, Gamma Ray Observations
  38. IPN localization of GRB000812
  39. IPN localization of GRB000811
  40. GRB000801, Gamma Ray Observations
  41. GRB000801, VLT-Antu R-band observations
  42. GRB 991208 Host Galaxy Imaging
  43. IPN localization of GRB000801
  44. IPN localization of GRB000730B
  45. GRB 990510: Possible detection of a host galaxy
  46. GRB 990510 Host Galaxy Discovery
  47. GRB 990705, HST/STIS observations of the host galaxy
  48. GRB 990712: Late time HST/STIS Observations
  49. GRB 991216, HST/STIS observations
  50. GRB000630, optical observations
  51. GRB000630, Revised BVRI Field Photometry
  52. GRB000630, Optical Observations
  53. GRB000630, optical observations
  54. GRB000630, optical observations
  55. GRB000630, BVRI Field Photometry
  56. GRB000630, optical observations
  57. GRB000630: Optical observations
  58. possible optical counterpart of GRB 000630
  59. IPN triangulation of GRB000630
  60. GRB 000620, optical observations
  61. GRB000418, HST/STIS Observations
  62. GRB990123: Late-time HST/STIS observations of the host
  63. GRB000623
  64. GRB000620, optical observations
  65. GRB000615: H-band observations
  66. GRB000620 - Optical observations
  67. GRB000620 Optical observations
  68. GRB000620: BeppoSAX WFC and GRBM detection
  69. GRB000615, Radio observations
  70. GRB000607, optical observations
  71. GRB 000615: NIR further observations
  72. BeppoSAX ALERT: GRB000620
  73. GRB000620: BeppoSAX Alert
  74. GRB000616 optical observations
  75. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  76. GRB000615, further R-band photometry
  77. GRB 000615: NIR observations
  78. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  79. GRB000615, R-band photometry
  80. GRB000615: BeppoSAX GRB Alert
  81. The Hosts of GRB 980703 and GRB 971214
  82. GRB 000301C: Further Late-Time HST/STIS observations
  83. GRB000528: follow-up X-ray measurements and update of IPN annulus
  84. GRB000607, Radio Observations
  85. GRB000604 - Optical observations
  86. GRB000604, optical observations
  87. GRB000528, optical observations at ESO
  88. GRB 000418: Detection of the Host Galaxy
  89. GRB000604, optical observations, comparison with DPOSS
  90. GRB000604 [IPN Position]
  91. GRB000528, Radio Observations
  92. X-ray Afterglow of GRB 000529
  93. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  94. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  95. GRB000519: Optical observations
  96. GRB 000528 - WFC measurements
  97. GRB000528: BeppoSAX GRBM observations
  98. GRB000519, BVRI field photometry
  99. IPN triangulation of GRB000519
  100. GRB000508B, optical photometry

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