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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"

44622 results found.

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

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