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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"

45444 results found.

  1. GRB 991216, HST/STIS observations
  2. GRB000620, Radio Observations
  3. GRB981226, HST/STIS observations of the host galaxy
  4. GRB000630, optical observations
  5. GRB 000630: Detection of the Optical Afterglow
  6. GRB000630, Revised BVRI Field Photometry
  7. GRB000630, Optical Observations
  8. GRB000630, optical observations
  9. GRB000630, optical observations
  10. GRB000630, BVRI Field Photometry
  11. GRB000630, optical observations
  12. GRB000630, optical observations
  13. GRB000630: Optical observations
  14. GRB000630, Radio Observations
  15. possible optical counterpart of GRB 000630
  16. IPN triangulation of GRB000630
  17. GRB 000623, optical observations
  18. GRB 000620, optical observations
  19. GRB000418, HST/STIS Observations
  20. GRB990123: Late-time HST/STIS observations of the host
  21. GRB 990506, HST/STIS Observations of the Host Galaxy
  22. GRB000623
  23. GRB 000620: J-band observations
  24. GRB000620, optical observations
  25. GRB000615: H-band observations
  26. GRB990308, HST/STIS observations of the host galaxy
  27. GRB000620 - Optical observations
  28. GRB000620 Optical observations
  29. IPN annulus for GRB000620
  30. GRB000620: BeppoSAX WFC and GRBM detection
  31. GRB000615, Radio observations
  32. GRB000607, optical observations
  33. GRB 000615: NIR further observations
  34. GRB000620: refined BeppoSAX/WFC coordinates
  35. BeppoSAX ALERT: GRB000620
  36. GRB000620: BeppoSAX Alert
  37. GRB990123, HST/STIS observations of the host galaxy
  38. GRB000616 optical observations
  39. GRB 000615, near-infrared observations
  40. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  41. GRB000616 [IPN Position]
  42. GRB000615B [IPN Position]
  43. GRB000615, further R-band photometry
  44. GRB 000615: NIR observations
  45. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  46. GRB000615, R-band photometry
  47. GRB000615: BeppoSAX refined coordinates
  48. GRB980425, HST/STIS observations of the host galaxy
  49. GRB000615: BeppoSAX GRB Alert
  50. The Hosts of GRB 980703 and GRB 971214
  51. GRB 000301C: Further Late-Time HST/STIS observations
  52. GRB000528: follow-up X-ray measurements and update of IPN annulus
  53. Optical Follow-up of GRB000529 Error Box
  54. GRB980519, HST/STIS observations of the host galaxy
  55. GRB000607, Radio Observations
  56. BeppoSAX X-ray transient/possible GRB000608
  57. GRB000604 optical non-detection
  58. GRB000604 - Optical observations
  59. GRB000607, A SHORT, HARD BURST
  60. GRB000604, optical observations
  61. GRB000528, optical observations at ESO
  62. GRB 000604 optical observations
  63. GRB 000418: Detection of the Host Galaxy
  64. GRB000604, optical observations, comparison with DPOSS
  65. GRB000604 [IPN Position]
  66. GRB000528, Radio Observations
  67. X-ray Afterglow of GRB 000529
  68. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  69. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  70. GRB000529: Optical Observations
  71. IPN localization and time history of GRB000528
  72. New IPN localization of GRB000529
  73. GRB000519: Optical observations
  74. IPN localization of GRB000529
  75. GRB 000528 - WFC measurements
  76. GRB000529: BeppoSAX WFC position
  77. GRB000528: BeppoSAX GRBM observations
  78. GRB 000528 Optical Observations
  79. GRB000519, BVRI field photometry
  80. IPN triangulation of GRB000519
  81. IPN triangulation of GRB000516
  82. Re: GRB000508B : Optical observations
  83. GRB 000418, Optical observation
  84. GRB000508B, optical photometry
  85. GRB000508B, BVR field photometry
  86. Possible GRB-related phenomenon
  87. RXTE/ASM and IPN localization of GRB 000508B
  88. GRB000424, UBVRI field photometry
  89. GRB 000424 Optical Observations
  90. GRB000418, UBVRI field photometry update
  91. The redshift of GRB 000418
  92. GRB000424, optical observations
  93. GRB 000429, optical observation
  94. GRB 000429, UBVRI field photometry
  95. IPN localization of GRB000429
  96. GRB 000418, UBVRI field photometry
  97. GRB000418, Radio detection
  98. GRB000418, K'-band photometry
  99. GRB 000418, Optical Observation
  100. GRB 000418, optical observation

Advanced

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