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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. GRB000926: Optical observations
  2. CONCAM crude optical limits before and after GRB000926
  3. GRB 000926: Preliminary R-band Lightcurve
  4. GRB 000926 HST/Chandra TOO Status
  5. Spectroscopic Redshift of GRB 000926
  6. GRB 000926, Optical Observation
  7. GRB000926, radio observations
  8. GRB 000926: Optical candidate
  9. Optical candidate for GRB000926
  10. IPN triangulation of GRB000926
  11. IPN triangulation of GRB000926
  12. GRB 000911, BVRI field photometry
  13. GRB000911: Corrected coordinates
  14. GRB000911: Sub-millimeter observations
  15. IPN triangulation of GRB000925
  16. GRB000911: Optical Transient
  17. GRB000911, Radio and Optical observations
  18. GRB000911, Radio observations
  19. GRB000911: Optical observations
  20. IPN triangulation of GRB000911
  21. IPN triangulation of GRB000910
  22. False GRB alarm from RXTE/ASM on 8 Sept 2000
  23. GRB 000830: Optical observations
  24. GRB000830: Optical observations
  25. GRB000830, TNG B-band observations
  26. GRB000830, BVRI field photometry
  27. GRB000830: Optical observations
  28. GRB000210, Optical observations
  29. Chandra Position of GRB000210
  30. "Snapshot" afterglow IDs and GRB 000830
  31. GRB000830: Optical observations
  32. IPN triangulation of GRB000830
  33. HST/STIS observations of the host galaxy of GRB 980329
  34. HST/STIS observations of the chaotic environment of GRB 980613
  35. IPN localization of GRB000820
  36. SGR 1806-20 burst activity
  37. GRB000812, TNG R-band observations
  38. GRB000801 & GRB000730, Gamma Ray Observations
  39. GRB000730, Gamma Ray Observations
  40. GRB000812, Radio observations
  41. IPN localization of GRB000812
  42. IPN localization of GRB000811
  43. GRB000801, Gamma Ray Observations
  44. GRB000801, VLT-Antu R-band observations
  45. GRB000301C, UBVI optical observations
  46. GRB000801, Radio Observations
  47. GRB 991208 Host Galaxy Imaging
  48. Updated IPN coordinates for GRB000801
  49. IPN localization of GRB000801
  50. IPN localization of GRB000801
  51. IPN localization of GRB000730B
  52. IPN localization of GRB000730B
  53. IPN localization of GRB000730
  54. GRB 990510: Possible detection of a host galaxy
  55. GRB 990510 Host Galaxy Discovery
  56. GRB 000727, optical observations
  57. IPN localization of GRB000727
  58. GRB 990705, HST/STIS observations of the host galaxy
  59. GRB 990712: Late time HST/STIS Observations
  60. GRB 991216, HST/STIS observations
  61. GRB000620, Radio Observations
  62. GRB981226, HST/STIS observations of the host galaxy
  63. GRB000630, optical observations
  64. GRB 000630: Detection of the Optical Afterglow
  65. GRB000630, Revised BVRI Field Photometry
  66. GRB000630, Optical Observations
  67. GRB000630, optical observations
  68. GRB000630, optical observations
  69. GRB000630, BVRI Field Photometry
  70. GRB000630, optical observations
  71. GRB000630, optical observations
  72. GRB000630: Optical observations
  73. GRB000630, Radio Observations
  74. possible optical counterpart of GRB 000630
  75. IPN triangulation of GRB000630
  76. GRB 000623, optical observations
  77. GRB 000620, optical observations
  78. GRB000418, HST/STIS Observations
  79. GRB990123: Late-time HST/STIS observations of the host
  80. GRB 990506, HST/STIS Observations of the Host Galaxy
  81. GRB000623
  82. GRB 000620: J-band observations
  83. GRB000620, optical observations
  84. GRB000615: H-band observations
  85. GRB990308, HST/STIS observations of the host galaxy
  86. GRB000620 - Optical observations
  87. GRB000620 Optical observations
  88. IPN annulus for GRB000620
  89. GRB000620: BeppoSAX WFC and GRBM detection
  90. GRB000615, Radio observations
  91. GRB000607, optical observations
  92. GRB 000615: NIR further observations
  93. GRB000620: refined BeppoSAX/WFC coordinates
  94. BeppoSAX ALERT: GRB000620
  95. GRB000620: BeppoSAX Alert
  96. GRB990123, HST/STIS observations of the host galaxy
  97. GRB000616 optical observations
  98. GRB 000615, near-infrared observations
  99. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  100. GRB000616 [IPN Position]

Advanced

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