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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"
  1. GRB000911: Optical observations
  2. IPN triangulation of GRB000911
  3. IPN triangulation of GRB000910
  4. False GRB alarm from RXTE/ASM on 8 Sept 2000
  5. GRB 000830: Optical observations
  6. GRB000830: Optical observations
  7. GRB000830, TNG B-band observations
  8. GRB000830, BVRI field photometry
  9. GRB000830: Optical observations
  10. GRB000210, Optical observations
  11. Chandra Position of GRB000210
  12. "Snapshot" afterglow IDs and GRB 000830
  13. GRB000830: Optical observations
  14. IPN triangulation of GRB000830
  15. HST/STIS observations of the host galaxy of GRB 980329
  16. HST/STIS observations of the chaotic environment of GRB 980613
  17. IPN localization of GRB000820
  18. SGR 1806-20 burst activity
  19. GRB000812, TNG R-band observations
  20. GRB000801 & GRB000730, Gamma Ray Observations
  21. GRB000730, Gamma Ray Observations
  22. GRB000812, Radio observations
  23. IPN localization of GRB000812
  24. IPN localization of GRB000811
  25. GRB000801, Gamma Ray Observations
  26. GRB000801, VLT-Antu R-band observations
  27. GRB000301C, UBVI optical observations
  28. GRB000801, Radio Observations
  29. GRB 991208 Host Galaxy Imaging
  30. Updated IPN coordinates for GRB000801
  31. IPN localization of GRB000801
  32. IPN localization of GRB000801
  33. IPN localization of GRB000730B
  34. IPN localization of GRB000730B
  35. IPN localization of GRB000730
  36. GRB 990510: Possible detection of a host galaxy
  37. GRB 990510 Host Galaxy Discovery
  38. GRB 000727, optical observations
  39. IPN localization of GRB000727
  40. GRB 990705, HST/STIS observations of the host galaxy
  41. GRB 990712: Late time HST/STIS Observations
  42. GRB 991216, HST/STIS observations
  43. GRB000620, Radio Observations
  44. GRB981226, HST/STIS observations of the host galaxy
  45. GRB000630, optical observations
  46. GRB 000630: Detection of the Optical Afterglow
  47. GRB000630, Revised BVRI Field Photometry
  48. GRB000630, Optical Observations
  49. GRB000630, optical observations
  50. GRB000630, optical observations
  51. GRB000630, BVRI Field Photometry
  52. GRB000630, optical observations
  53. GRB000630, optical observations
  54. GRB000630: Optical observations
  55. GRB000630, Radio Observations
  56. possible optical counterpart of GRB 000630
  57. IPN triangulation of GRB000630
  58. GRB 000623, optical observations
  59. GRB 000620, optical observations
  60. GRB000418, HST/STIS Observations
  61. GRB990123: Late-time HST/STIS observations of the host
  62. GRB 990506, HST/STIS Observations of the Host Galaxy
  63. GRB000623
  64. GRB 000620: J-band observations
  65. GRB000620, optical observations
  66. GRB000615: H-band observations
  67. GRB990308, HST/STIS observations of the host galaxy
  68. GRB000620 - Optical observations
  69. GRB000620 Optical observations
  70. IPN annulus for GRB000620
  71. GRB000620: BeppoSAX WFC and GRBM detection
  72. GRB000615, Radio observations
  73. GRB000607, optical observations
  74. GRB 000615: NIR further observations
  75. GRB000620: refined BeppoSAX/WFC coordinates
  76. BeppoSAX ALERT: GRB000620
  77. GRB000620: BeppoSAX Alert
  78. GRB990123, HST/STIS observations of the host galaxy
  79. GRB000616 optical observations
  80. GRB 000615, near-infrared observations
  81. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  82. GRB000616 [IPN Position]
  83. GRB000615B [IPN Position]
  84. GRB000615, further R-band photometry
  85. GRB 000615: NIR observations
  86. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  87. GRB000615, R-band photometry
  88. GRB000615: BeppoSAX refined coordinates
  89. GRB980425, HST/STIS observations of the host galaxy
  90. GRB000615: BeppoSAX GRB Alert
  91. The Hosts of GRB 980703 and GRB 971214
  92. GRB 000301C: Further Late-Time HST/STIS observations
  93. GRB000528: follow-up X-ray measurements and update of IPN annulus
  94. Optical Follow-up of GRB000529 Error Box
  95. GRB980519, HST/STIS observations of the host galaxy
  96. GRB000607, Radio Observations
  97. BeppoSAX X-ray transient/possible GRB000608
  98. GRB000604 optical non-detection
  99. GRB000604 - Optical observations
  100. GRB000607, A SHORT, HARD BURST

Advanced

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