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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"

26139 results found.

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

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