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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. CONCAM null result on GRB001005
  2. IPN triangulation of GRB001007
  3. GRB 000926 : the host galaxy
  4. HETE-2 Launches Successfully
  5. IPN triangulation of GRB001005
  6. HETE-2 48 hour Launch Delay
  7. GRB 000926 Chandra Observation
  8. IPN triangulation of GRB 001004
  9. Public availability of BeppoSAX data of GRB000926
  10. GRB000926: X-ray afterglow by BeppoSAX: revised fluxes (fwd)
  11. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  12. GRB000926 - Optical observations
  13. GRB000926 - Optical observations
  14. GRB 000926, Optical Decay
  15. GRB000911: VLT infrared observation
  16. GRB000926 - Optical observations
  17. GRB000926 - Optical observations
  18. GRB 000926: optical observations
  19. GRB 000926, Optical Observations
  20. GRB000926 - Optical observations
  21. GRB000911: optical VLT observations
  22. GRB000926 K'-band Observation
  23. GRB000926 : increasing optical decay slope
  24. GRB000926 optical observations
  25. GRB000926 - Optical observations
  26. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  27. J and K band observations of GRB 000926
  28. GRB000911 Optical Observations
  29. GRB 000926: Lightcurve Update and Predictions
  30. GRB 000926, optical observation by Oksanen (vsnet-grb)
  31. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  32. GRB000926: Optical observations
  33. CONCAM crude optical limits before and after GRB000926
  34. GRB 000926: Preliminary R-band Lightcurve
  35. GRB 000926 HST/Chandra TOO Status
  36. Spectroscopic Redshift of GRB 000926
  37. GRB 000926, Optical Observation
  38. GRB000926, radio observations
  39. GRB 000926: Optical candidate
  40. Optical candidate for GRB000926
  41. IPN triangulation of GRB000926
  42. IPN triangulation of GRB000926
  43. GRB 000911, BVRI field photometry
  44. GRB000911: Corrected coordinates
  45. GRB000911: Sub-millimeter observations
  46. IPN triangulation of GRB000925
  47. GRB000911: Optical Transient
  48. GRB000911, Radio and Optical observations
  49. GRB000911, Radio observations
  50. GRB000911: Optical observations
  51. IPN triangulation of GRB000911
  52. IPN triangulation of GRB000910
  53. False GRB alarm from RXTE/ASM on 8 Sept 2000
  54. GRB 000830: Optical observations
  55. GRB000830: Optical observations
  56. GRB000830, TNG B-band observations
  57. GRB000830, BVRI field photometry
  58. GRB000830: Optical observations
  59. GRB000210, Optical observations
  60. Chandra Position of GRB000210
  61. "Snapshot" afterglow IDs and GRB 000830
  62. GRB000830: Optical observations
  63. IPN triangulation of GRB000830
  64. HST/STIS observations of the host galaxy of GRB 980329
  65. HST/STIS observations of the chaotic environment of GRB 980613
  66. IPN localization of GRB000820
  67. SGR 1806-20 burst activity
  68. GRB000812, TNG R-band observations
  69. GRB000801 & GRB000730, Gamma Ray Observations
  70. GRB000730, Gamma Ray Observations
  71. GRB000812, Radio observations
  72. IPN localization of GRB000812
  73. IPN localization of GRB000811
  74. GRB000801, Gamma Ray Observations
  75. GRB000801, VLT-Antu R-band observations
  76. GRB000301C, UBVI optical observations
  77. GRB000801, Radio Observations
  78. GRB 991208 Host Galaxy Imaging
  79. Updated IPN coordinates for GRB000801
  80. IPN localization of GRB000801
  81. IPN localization of GRB000801
  82. IPN localization of GRB000730B
  83. IPN localization of GRB000730B
  84. IPN localization of GRB000730
  85. GRB 990510: Possible detection of a host galaxy
  86. GRB 990510 Host Galaxy Discovery
  87. GRB 000727, optical observations
  88. IPN localization of GRB000727
  89. GRB 990705, HST/STIS observations of the host galaxy
  90. GRB 990712: Late time HST/STIS Observations
  91. GRB 991216, HST/STIS observations
  92. GRB000620, Radio Observations
  93. GRB981226, HST/STIS observations of the host galaxy
  94. GRB000630, optical observations
  95. GRB 000630: Detection of the Optical Afterglow
  96. GRB000630, Revised BVRI Field Photometry
  97. GRB000630, Optical Observations
  98. GRB000630, optical observations
  99. GRB000630, optical observations
  100. GRB000630, BVRI Field Photometry

Advanced

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