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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"

28043 results found.

  1. ASM Localization of GRB 001025
  2. GRB001007, Radio observations
  3. GRB 001018, Possible Radio Afterglow
  4. GRB001018, Gamma Ray Observations
  5. IPN TRIANGULATION OF GRB001019
  6. IPN TRIANGULATION OF GRB001018
  7. IPN TRIANGULATION OF GRB 001017
  8. V,R,I band observations of GRB000926
  9. HETE positions added to GCN
  10. GRB000926 - Amateur Optical Observations
  11. CONCAM null result on GRB001005
  12. IPN triangulation of GRB001005
  13. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  14. GRB000926 - Optical observations
  15. GRB000926 - Optical observations
  16. GRB 000926, Optical Decay
  17. GRB000911: VLT infrared observation
  18. GRB 000926, Optical Observations
  19. GRB000926 K'-band Observation
  20. J and K band observations of GRB 000926
  21. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  22. CONCAM crude optical limits before and after GRB000926
  23. GRB 000926: Preliminary R-band Lightcurve
  24. Spectroscopic Redshift of GRB 000926
  25. GRB 000926: Optical candidate
  26. Optical candidate for GRB000926
  27. GRB 000911, BVRI field photometry
  28. GRB000911, Radio and Optical observations
  29. GRB000911: Optical observations
  30. GRB000830, BVRI field photometry
  31. GRB000210, Optical observations
  32. "Snapshot" afterglow IDs and GRB 000830
  33. GRB000730, Gamma Ray Observations
  34. GRB000812, Radio observations
  35. GRB000801, Gamma Ray Observations
  36. GRB000801, VLT-Antu R-band observations
  37. GRB 991208 Host Galaxy Imaging
  38. IPN localization of GRB000730B
  39. GRB 990510: Possible detection of a host galaxy
  40. GRB 990510 Host Galaxy Discovery
  41. IPN localization of GRB000727
  42. GRB 990712: Late time HST/STIS Observations
  43. GRB 991216, HST/STIS observations
  44. GRB000620, Radio 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. GRB000630, Radio Observations
  54. possible optical counterpart of GRB 000630
  55. GRB 000620, optical observations
  56. GRB000418, HST/STIS Observations
  57. GRB990123: Late-time HST/STIS observations of the host
  58. GRB000620, optical observations
  59. GRB000615: H-band observations
  60. GRB990308, HST/STIS observations of the host galaxy
  61. GRB000620 - Optical observations
  62. GRB000620 Optical observations
  63. GRB000620: BeppoSAX WFC and GRBM detection
  64. GRB000607, optical observations
  65. GRB 000615: NIR further observations
  66. GRB990123, HST/STIS observations of the host galaxy
  67. GRB000616 optical observations
  68. GRB 000615, near-infrared observations
  69. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  70. GRB000615, further R-band photometry
  71. GRB 000615: NIR observations
  72. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  73. GRB000615, R-band photometry
  74. The Hosts of GRB 980703 and GRB 971214
  75. GRB 000301C: Further Late-Time HST/STIS observations
  76. GRB000528: follow-up X-ray measurements and update of IPN annulus
  77. GRB980519, HST/STIS observations of the host galaxy
  78. GRB000604 optical non-detection
  79. GRB000604 - Optical observations
  80. GRB000604, optical observations
  81. GRB000528, optical observations at ESO
  82. GRB 000604 optical observations
  83. GRB 000418: Detection of the Host Galaxy
  84. GRB000604, optical observations, comparison with DPOSS
  85. GRB000528, Radio Observations
  86. X-ray Afterglow of GRB 000529
  87. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  88. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  89. GRB 000528 - WFC measurements
  90. GRB000519, BVRI field photometry
  91. IPN triangulation of GRB000519
  92. GRB000508B, optical photometry
  93. GRB000508B, BVR field photometry
  94. Possible GRB-related phenomenon
  95. RXTE/ASM and IPN localization of GRB 000508B
  96. GRB000424, UBVRI field photometry
  97. GRB000418, UBVRI field photometry update
  98. GRB000424, optical observations
  99. GRB 000429, optical observation
  100. GRB 000429, UBVRI field photometry

Advanced

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