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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"

45645 results found.

  1. GRB000630, BVRI Field Photometry
  2. GRB000630, optical observations
  3. GRB000630, optical observations
  4. GRB000630: Optical observations
  5. GRB000630, Radio Observations
  6. possible optical counterpart of GRB 000630
  7. IPN triangulation of GRB000630
  8. GRB 000623, optical observations
  9. GRB 000620, optical observations
  10. GRB000418, HST/STIS Observations
  11. GRB990123: Late-time HST/STIS observations of the host
  12. GRB 990506, HST/STIS Observations of the Host Galaxy
  13. GRB000623
  14. GRB 000620: J-band observations
  15. GRB000620, optical observations
  16. GRB000615: H-band observations
  17. GRB990308, HST/STIS observations of the host galaxy
  18. GRB000620 - Optical observations
  19. GRB000620 Optical observations
  20. IPN annulus for GRB000620
  21. GRB000620: BeppoSAX WFC and GRBM detection
  22. GRB000615, Radio observations
  23. GRB000607, optical observations
  24. GRB 000615: NIR further observations
  25. GRB000620: refined BeppoSAX/WFC coordinates
  26. BeppoSAX ALERT: GRB000620
  27. GRB000620: BeppoSAX Alert
  28. GRB990123, HST/STIS observations of the host galaxy
  29. GRB000616 optical observations
  30. GRB 000615, near-infrared observations
  31. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  32. GRB000616 [IPN Position]
  33. GRB000615B [IPN Position]
  34. GRB000615, further R-band photometry
  35. GRB 000615: NIR observations
  36. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  37. GRB000615, R-band photometry
  38. GRB000615: BeppoSAX refined coordinates
  39. GRB980425, HST/STIS observations of the host galaxy
  40. GRB000615: BeppoSAX GRB Alert
  41. The Hosts of GRB 980703 and GRB 971214
  42. GRB 000301C: Further Late-Time HST/STIS observations
  43. GRB000528: follow-up X-ray measurements and update of IPN annulus
  44. Optical Follow-up of GRB000529 Error Box
  45. GRB980519, HST/STIS observations of the host galaxy
  46. GRB000607, Radio Observations
  47. BeppoSAX X-ray transient/possible GRB000608
  48. GRB000604 optical non-detection
  49. GRB000604 - Optical observations
  50. GRB000607, A SHORT, HARD BURST
  51. GRB000604, optical observations
  52. GRB000528, optical observations at ESO
  53. GRB 000604 optical observations
  54. GRB 000418: Detection of the Host Galaxy
  55. GRB000604, optical observations, comparison with DPOSS
  56. GRB000604 [IPN Position]
  57. GRB000528, Radio Observations
  58. X-ray Afterglow of GRB 000529
  59. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  60. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  61. GRB000529: Optical Observations
  62. IPN localization and time history of GRB000528
  63. New IPN localization of GRB000529
  64. GRB000519: Optical observations
  65. IPN localization of GRB000529
  66. GRB 000528 - WFC measurements
  67. GRB000529: BeppoSAX WFC position
  68. GRB000528: BeppoSAX GRBM observations
  69. GRB 000528 Optical Observations
  70. GRB000519, BVRI field photometry
  71. IPN triangulation of GRB000519
  72. IPN triangulation of GRB000516
  73. Re: GRB000508B : Optical observations
  74. GRB 000418, Optical observation
  75. GRB000508B, optical photometry
  76. GRB000508B, BVR field photometry
  77. Possible GRB-related phenomenon
  78. RXTE/ASM and IPN localization of GRB 000508B
  79. GRB000424, UBVRI field photometry
  80. GRB 000424 Optical Observations
  81. GRB000418, UBVRI field photometry update
  82. The redshift of GRB 000418
  83. GRB000424, optical observations
  84. GRB 000429, optical observation
  85. GRB 000429, UBVRI field photometry
  86. IPN localization of GRB000429
  87. GRB 000418, UBVRI field photometry
  88. GRB000418, Radio detection
  89. GRB000418, K'-band photometry
  90. GRB 000418, Optical Observation
  91. GRB 000418, optical observation
  92. GRB000424 Optical Observations
  93. GRB 000418, Optical Observation
  94. GRB000424, optical observations
  95. GRB000424, optical observations
  96. GRB 000424, Optical Observations
  97. GRB 000418, Optical Observation
  98. GRB000418, near-infrared observations
  99. BeppoSAX GRB000424
  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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