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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"

38394 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. IPN annulus for GRB000620
  29. GRB000620: BeppoSAX WFC and GRBM detection
  30. GRB000615, Radio observations
  31. GRB000607, optical observations
  32. GRB 000615: NIR further observations
  33. GRB000620: refined BeppoSAX/WFC coordinates
  34. BeppoSAX ALERT: GRB000620
  35. GRB000620: BeppoSAX Alert
  36. GRB990123, HST/STIS observations of the host galaxy
  37. GRB000616 optical observations
  38. GRB 000615, near-infrared observations
  39. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  40. GRB000616 [IPN Position]
  41. GRB000615B [IPN Position]
  42. GRB000615, further R-band photometry
  43. GRB 000615: NIR observations
  44. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  45. GRB000615, R-band photometry
  46. GRB000615: BeppoSAX refined coordinates
  47. GRB980425, HST/STIS observations of the host galaxy
  48. GRB000615: BeppoSAX GRB Alert
  49. The Hosts of GRB 980703 and GRB 971214
  50. GRB 000301C: Further Late-Time HST/STIS observations
  51. GRB000528: follow-up X-ray measurements and update of IPN annulus
  52. Optical Follow-up of GRB000529 Error Box
  53. GRB980519, HST/STIS observations of the host galaxy
  54. GRB000607, Radio Observations
  55. BeppoSAX X-ray transient/possible GRB000608
  56. GRB000604 optical non-detection
  57. GRB000604 - Optical observations
  58. GRB000607, A SHORT, HARD BURST
  59. GRB000604, optical observations
  60. GRB000528, optical observations at ESO
  61. GRB 000604 optical observations
  62. GRB 000418: Detection of the Host Galaxy
  63. GRB000604, optical observations, comparison with DPOSS
  64. GRB000604 [IPN Position]
  65. GRB000528, Radio Observations
  66. X-ray Afterglow of GRB 000529
  67. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  68. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  69. GRB000529: Optical Observations
  70. IPN localization and time history of GRB000528
  71. New IPN localization of GRB000529
  72. GRB000519: Optical observations
  73. IPN localization of GRB000529
  74. GRB 000528 - WFC measurements
  75. GRB000529: BeppoSAX WFC position
  76. GRB000528: BeppoSAX GRBM observations
  77. GRB 000528 Optical Observations
  78. GRB000519, BVRI field photometry
  79. IPN triangulation of GRB000519
  80. IPN triangulation of GRB000516
  81. Re: GRB000508B : Optical observations
  82. GRB 000418, Optical observation
  83. GRB000508B, optical photometry
  84. GRB000508B, BVR field photometry
  85. Possible GRB-related phenomenon
  86. RXTE/ASM and IPN localization of GRB 000508B
  87. GRB000424, UBVRI field photometry
  88. GRB 000424 Optical Observations
  89. GRB000418, UBVRI field photometry update
  90. The redshift of GRB 000418
  91. GRB000424, optical observations
  92. GRB 000429, optical observation
  93. GRB 000429, UBVRI field photometry
  94. IPN localization of GRB000429
  95. GRB 000418, UBVRI field photometry
  96. GRB000418, Radio detection
  97. GRB000418, K'-band photometry
  98. GRB 000418, Optical Observation
  99. GRB 000418, optical observation
  100. GRB000424 Optical Observations

Advanced

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