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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"

23149 results found.

  1. GRB000926 - Optical observations
  2. GRB000926 - Optical observations
  3. GRB000926 K'-band Observation
  4. GRB000926 optical observations
  5. GRB000926 - Optical observations
  6. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  7. CONCAM crude optical limits before and after GRB000926
  8. GRB 000926: Preliminary R-band Lightcurve
  9. IPN triangulation of GRB000926
  10. IPN triangulation of GRB000926
  11. GRB 000911, BVRI field photometry
  12. IPN triangulation of GRB000925
  13. IPN triangulation of GRB000911
  14. IPN triangulation of GRB000910
  15. False GRB alarm from RXTE/ASM on 8 Sept 2000
  16. GRB 000830: Optical observations
  17. GRB000830, TNG B-band observations
  18. GRB000830, BVRI field photometry
  19. GRB000210, Optical observations
  20. IPN triangulation of GRB000830
  21. IPN localization of GRB000820
  22. GRB000812, TNG R-band observations
  23. GRB000730, Gamma Ray Observations
  24. GRB000812, Radio observations
  25. IPN localization of GRB000812
  26. IPN localization of GRB000811
  27. GRB000801, Gamma Ray 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 GRB000730B
  33. IPN localization of GRB000730B
  34. IPN localization of GRB000730
  35. GRB 000727, optical observations
  36. IPN localization of GRB000727
  37. GRB 990705, HST/STIS observations of the host galaxy
  38. GRB 991216, HST/STIS observations
  39. GRB 000630: Detection of the Optical Afterglow
  40. GRB000630, Revised BVRI Field Photometry
  41. GRB000630, optical observations
  42. GRB000630, BVRI Field Photometry
  43. GRB000630, optical observations
  44. GRB000630, optical observations
  45. GRB000630: Optical observations
  46. IPN triangulation of GRB000630
  47. GRB 000623, optical observations
  48. GRB 000620, optical observations
  49. GRB000418, HST/STIS Observations
  50. GRB000623
  51. GRB 000620: J-band observations
  52. GRB000620, optical observations
  53. GRB000615: H-band observations
  54. GRB000620: BeppoSAX WFC and GRBM detection
  55. GRB000615, Radio observations
  56. GRB000607, optical observations
  57. GRB 000615, near-infrared observations
  58. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  59. GRB000616 [IPN Position]
  60. GRB000615B [IPN Position]
  61. GRB000615, further R-band photometry
  62. GRB000615, R-band photometry
  63. GRB 000301C: Further Late-Time HST/STIS observations
  64. GRB000528: follow-up X-ray measurements and update of IPN annulus
  65. Optical Follow-up of GRB000529 Error Box
  66. GRB000607, Radio Observations
  67. GRB000604 optical non-detection
  68. GRB000604 - Optical observations
  69. GRB000607, A SHORT, HARD BURST
  70. GRB000604, optical observations
  71. GRB 000604 optical observations
  72. GRB 000418: Detection of the Host Galaxy
  73. GRB000604 [IPN Position]
  74. X-ray Afterglow of GRB 000529
  75. GRB000519: Optical observations
  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. GRB 000429, optical observation
  92. GRB 000429, UBVRI field photometry
  93. IPN localization of GRB000429
  94. GRB 000418, UBVRI field photometry
  95. GRB000418, K'-band photometry
  96. GRB 000418, Optical Observation
  97. GRB 000418, optical observation
  98. GRB000424 Optical Observations
  99. GRB 000418, Optical Observation
  100. GRB000424, optical observations

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