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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"

28041 results found.

  1. GRB 001018, Possible Radio Afterglow
  2. GRB001018, Gamma Ray Observations
  3. IPN TRIANGULATION OF GRB001019
  4. IPN TRIANGULATION OF GRB001018
  5. IPN TRIANGULATION OF GRB 001017
  6. V,R,I band observations of GRB000926
  7. HETE positions added to GCN
  8. GRB000926 - Amateur Optical Observations
  9. CONCAM null result on GRB001005
  10. IPN triangulation of GRB001005
  11. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  12. GRB000926 - Optical observations
  13. GRB000926 - Optical observations
  14. GRB 000926, Optical Decay
  15. GRB000911: VLT infrared observation
  16. GRB 000926, Optical Observations
  17. GRB000926 K'-band Observation
  18. J and K band observations of GRB 000926
  19. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  20. CONCAM crude optical limits before and after GRB000926
  21. GRB 000926: Preliminary R-band Lightcurve
  22. Spectroscopic Redshift of GRB 000926
  23. GRB 000926: Optical candidate
  24. Optical candidate for GRB000926
  25. GRB 000911, BVRI field photometry
  26. GRB000911, Radio and Optical observations
  27. GRB000911: Optical observations
  28. GRB000830, BVRI field photometry
  29. GRB000210, Optical observations
  30. "Snapshot" afterglow IDs and GRB 000830
  31. GRB000730, Gamma Ray Observations
  32. GRB000812, Radio observations
  33. GRB000801, Gamma Ray Observations
  34. GRB000801, VLT-Antu R-band observations
  35. GRB 991208 Host Galaxy Imaging
  36. IPN localization of GRB000730B
  37. GRB 990510: Possible detection of a host galaxy
  38. GRB 990510 Host Galaxy Discovery
  39. IPN localization of GRB000727
  40. GRB 990712: Late time HST/STIS Observations
  41. GRB 991216, HST/STIS observations
  42. GRB000620, Radio Observations
  43. GRB000630, optical observations
  44. GRB000630, Revised BVRI Field Photometry
  45. GRB000630, Optical Observations
  46. GRB000630, optical observations
  47. GRB000630, optical observations
  48. GRB000630, BVRI Field Photometry
  49. GRB000630, optical observations
  50. GRB000630: Optical observations
  51. GRB000630, Radio Observations
  52. possible optical counterpart of GRB 000630
  53. GRB 000620, optical observations
  54. GRB000418, HST/STIS Observations
  55. GRB990123: Late-time HST/STIS observations of the host
  56. GRB000620, optical observations
  57. GRB000615: H-band observations
  58. GRB990308, HST/STIS observations of the host galaxy
  59. GRB000620 - Optical observations
  60. GRB000620 Optical observations
  61. GRB000620: BeppoSAX WFC and GRBM detection
  62. GRB000607, optical observations
  63. GRB 000615: NIR further observations
  64. GRB990123, HST/STIS observations of the host galaxy
  65. GRB000616 optical observations
  66. GRB 000615, near-infrared observations
  67. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  68. GRB000615, further R-band photometry
  69. GRB 000615: NIR observations
  70. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  71. GRB000615, R-band photometry
  72. The Hosts of GRB 980703 and GRB 971214
  73. GRB 000301C: Further Late-Time HST/STIS observations
  74. GRB000528: follow-up X-ray measurements and update of IPN annulus
  75. GRB980519, HST/STIS observations of the host galaxy
  76. GRB000604 optical non-detection
  77. GRB000604 - Optical observations
  78. GRB000604, optical observations
  79. GRB000528, optical observations at ESO
  80. GRB 000604 optical observations
  81. GRB 000418: Detection of the Host Galaxy
  82. GRB000604, optical observations, comparison with DPOSS
  83. GRB000528, Radio Observations
  84. X-ray Afterglow of GRB 000529
  85. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  86. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  87. GRB 000528 - WFC measurements
  88. GRB000519, BVRI field photometry
  89. IPN triangulation of GRB000519
  90. GRB000508B, optical photometry
  91. GRB000508B, BVR field photometry
  92. Possible GRB-related phenomenon
  93. RXTE/ASM and IPN localization of GRB 000508B
  94. GRB000424, UBVRI field photometry
  95. GRB000418, UBVRI field photometry update
  96. GRB000424, optical observations
  97. GRB 000429, optical observation
  98. GRB 000429, UBVRI field photometry
  99. GRB 000418, UBVRI field photometry
  100. GRB 000418, optical observation

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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