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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"

28042 results found.

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

Advanced

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