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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"

15685 results found.

  1. GRB 000926 Chandra Observation
  2. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  3. GRB000926 - Optical observations
  4. GRB000926 - Optical observations
  5. GRB 000926, Optical Decay
  6. GRB000911: VLT infrared observation
  7. GRB000926 - Optical observations
  8. GRB000926 - Optical observations
  9. GRB 000926: optical observations
  10. GRB 000926, Optical Observations
  11. GRB000926 - Optical observations
  12. GRB000911: optical VLT observations
  13. GRB000926 K'-band Observation
  14. GRB000926 : increasing optical decay slope
  15. GRB000926 optical observations
  16. GRB000926 - Optical observations
  17. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  18. J and K band observations of GRB 000926
  19. GRB000911 Optical Observations
  20. GRB 000926: Lightcurve Update and Predictions
  21. GRB 000926, optical observation by Oksanen (vsnet-grb)
  22. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  23. GRB000926: Optical observations
  24. CONCAM crude optical limits before and after GRB000926
  25. GRB 000926: Preliminary R-band Lightcurve
  26. GRB 000926 HST/Chandra TOO Status
  27. Spectroscopic Redshift of GRB 000926
  28. GRB 000926, Optical Observation
  29. GRB000926, radio observations
  30. GRB 000926: Optical candidate
  31. Optical candidate for GRB000926
  32. GRB 000911, BVRI field photometry
  33. GRB000911: Sub-millimeter observations
  34. GRB000911: Optical Transient
  35. GRB000911, Radio and Optical observations
  36. GRB000911: Optical observations
  37. GRB 000830: Optical observations
  38. GRB000830: Optical observations
  39. GRB000830, TNG B-band observations
  40. GRB000830, BVRI field photometry
  41. GRB000830: Optical observations
  42. GRB000210, Optical observations
  43. Chandra Position of GRB000210
  44. "Snapshot" afterglow IDs and GRB 000830
  45. GRB000830: Optical observations
  46. HST/STIS observations of the host galaxy of GRB 980329
  47. HST/STIS observations of the chaotic environment of GRB 980613
  48. GRB000812, TNG R-band observations
  49. GRB000801, VLT-Antu R-band observations
  50. GRB000301C, UBVI optical observations
  51. GRB 000727, optical observations
  52. GRB 990712: Late time HST/STIS Observations
  53. GRB000630, optical observations
  54. GRB 000630: Detection of the Optical Afterglow
  55. GRB000630, Optical Observations
  56. GRB000630, optical observations
  57. GRB000630, optical observations
  58. GRB000630, BVRI Field Photometry
  59. GRB000630, optical observations
  60. GRB000630, optical observations
  61. GRB000630: Optical observations
  62. GRB000630, Radio Observations
  63. possible optical counterpart of GRB 000630
  64. GRB 000623, optical observations
  65. GRB 000620, optical observations
  66. GRB000418, HST/STIS Observations
  67. GRB 990506, HST/STIS Observations of the Host Galaxy
  68. GRB000620, optical observations
  69. GRB990308, HST/STIS observations of the host galaxy
  70. GRB000620 - Optical observations
  71. GRB000620 Optical observations
  72. GRB000607, optical observations
  73. GRB990123, HST/STIS observations of the host galaxy
  74. GRB000616 optical observations
  75. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  76. GRB000615, further R-band photometry
  77. The Hosts of GRB 980703 and GRB 971214
  78. GRB 000301C: Further Late-Time HST/STIS observations
  79. Optical Follow-up of GRB000529 Error Box
  80. GRB000604 optical non-detection
  81. GRB000604 - Optical observations
  82. GRB000604, optical observations
  83. GRB000528, optical observations at ESO
  84. GRB 000604 optical observations
  85. GRB 000418: Detection of the Host Galaxy
  86. GRB000604, optical observations, comparison with DPOSS
  87. GRB000529: Optical Observations
  88. GRB000519: Optical observations
  89. GRB 000528 Optical Observations
  90. GRB000519, BVRI field photometry
  91. Re: GRB000508B : Optical observations
  92. GRB 000418, Optical observation
  93. GRB000508B, optical photometry
  94. GRB000508B, BVR field photometry
  95. Possible GRB-related phenomenon
  96. GRB000424, UBVRI field photometry
  97. GRB 000424 Optical Observations
  98. GRB000418, UBVRI field photometry update
  99. GRB000424, optical observations
  100. GRB 000429, optical observation

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