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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"

37514 results found.

  1. GRB000812, Radio observations
  2. IPN localization of GRB000812
  3. IPN localization of GRB000811
  4. GRB000801, Gamma Ray Observations
  5. GRB000801, VLT-Antu R-band observations
  6. GRB 991208 Host Galaxy Imaging
  7. Updated IPN coordinates for GRB000801
  8. IPN localization of GRB000801
  9. IPN localization of GRB000730B
  10. IPN localization of GRB000730B
  11. IPN localization of GRB000730
  12. GRB 990510: Possible detection of a host galaxy
  13. GRB 990510 Host Galaxy Discovery
  14. GRB 000727, optical observations
  15. IPN localization of GRB000727
  16. GRB 990705, HST/STIS observations of the host galaxy
  17. GRB 990712: Late time HST/STIS Observations
  18. GRB 991216, HST/STIS observations
  19. GRB981226, HST/STIS observations of the host galaxy
  20. GRB 000630: Detection of the Optical Afterglow
  21. GRB000630, Revised BVRI Field Photometry
  22. GRB000630, Optical Observations
  23. GRB000630, optical observations
  24. GRB000630, BVRI Field Photometry
  25. GRB000630, optical observations
  26. GRB000630: Optical observations
  27. possible optical counterpart of GRB 000630
  28. IPN triangulation of GRB000630
  29. GRB 000623, optical observations
  30. GRB 000620, optical observations
  31. GRB000418, HST/STIS Observations
  32. GRB990123: Late-time HST/STIS observations of the host
  33. GRB 990506, HST/STIS Observations of the Host Galaxy
  34. GRB000623
  35. GRB 000620: J-band observations
  36. GRB990308, HST/STIS observations of the host galaxy
  37. IPN annulus for GRB000620
  38. GRB000615, Radio observations
  39. GRB000607, optical observations
  40. GRB 000615: NIR further observations
  41. BeppoSAX ALERT: GRB000620
  42. GRB000620: BeppoSAX Alert
  43. GRB990123, HST/STIS observations of the host galaxy
  44. GRB 000615, near-infrared observations
  45. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  46. GRB000616 [IPN Position]
  47. GRB000615B [IPN Position]
  48. GRB000615, further R-band photometry
  49. GRB 000615: NIR observations
  50. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  51. GRB000615, R-band photometry
  52. GRB980425, HST/STIS observations of the host galaxy
  53. GRB000615: BeppoSAX GRB Alert
  54. The Hosts of GRB 980703 and GRB 971214
  55. GRB 000301C: Further Late-Time HST/STIS observations
  56. GRB000528: follow-up X-ray measurements and update of IPN annulus
  57. GRB980519, HST/STIS observations of the host galaxy
  58. GRB000607, Radio Observations
  59. GRB000604 - Optical observations
  60. GRB000607, A SHORT, HARD BURST
  61. GRB000604, optical observations
  62. GRB000528, optical observations at ESO
  63. GRB 000604 optical observations
  64. GRB 000418: Detection of the Host Galaxy
  65. GRB000604, optical observations, comparison with DPOSS
  66. GRB000604 [IPN Position]
  67. X-ray Afterglow of GRB 000529
  68. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  69. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  70. IPN localization and time history of GRB000528
  71. New IPN localization of GRB000529
  72. GRB 000528 - WFC measurements
  73. GRB000528: BeppoSAX GRBM observations
  74. GRB 000528 Optical Observations
  75. GRB000519, BVRI field photometry
  76. IPN triangulation of GRB000519
  77. IPN triangulation of GRB000516
  78. Re: GRB000508B : Optical observations
  79. GRB 000418, Optical observation
  80. GRB000508B, optical photometry
  81. GRB000508B, BVR field photometry
  82. Possible GRB-related phenomenon
  83. RXTE/ASM and IPN localization of GRB 000508B
  84. GRB000424, UBVRI field photometry
  85. GRB 000424 Optical Observations
  86. GRB000418, UBVRI field photometry update
  87. The redshift of GRB 000418
  88. GRB 000429, optical observation
  89. GRB 000429, UBVRI field photometry
  90. IPN localization of GRB000429
  91. GRB 000418, UBVRI field photometry
  92. GRB000418, K'-band photometry
  93. GRB 000418, Optical Observation
  94. GRB 000418, optical observation
  95. GRB000424 Optical Observations
  96. GRB 000418, Optical Observation
  97. GRB 000424, Optical Observations
  98. GRB 000418, Optical Observation
  99. GRB000418, near-infrared observations
  100. Correction to IPN error box for GRB000419

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