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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"

16004 results found.

  1. GRB 001109: deep JHK upper limits
  2. GRB001109: Optical observations
  3. GRB001109, R-band optical observations
  4. GRB001109, Radio observations
  5. GRB001105, BVRI field photometry
  6. GRB 001105, R-band observation
  7. GRB 001025B, Optical obervations
  8. GRB 991208: HST Imaging of the Host Galaxy
  9. GRB000926: R-image of the host galaxy
  10. GRB 001025 Optical Observations
  11. GRB 001025A, optical observation
  12. GRB001007: Optical observations
  13. GRB001007, Radio observations
  14. GRB001019, Optical Observations
  15. GRB 000926: Improved Absorber Redshift
  16. The Likely Optical/Infrared Afterglow of GRB 001011
  17. GRB 001007, BVR-band observations
  18. GRB000926 - Amateur Optical Observations
  19. GRB001007: Optical observations
  20. CONCAM null result on GRB001005
  21. GRB 000926 : the host galaxy
  22. GRB 000926 Chandra Observation
  23. GRB000926: X-ray afterglow by BeppoSAX. Refined analysis
  24. GRB000926 - Optical observations
  25. GRB000926 - Optical observations
  26. GRB 000926, Optical Decay
  27. GRB000911: VLT infrared observation
  28. GRB000926 - Optical observations
  29. GRB000926 - Optical observations
  30. GRB 000926: optical observations
  31. GRB 000926, Optical Observations
  32. GRB000926 - Optical observations
  33. GRB000911: optical VLT observations
  34. GRB000926 K'-band Observation
  35. GRB000926 : increasing optical decay slope
  36. GRB000926 optical observations
  37. GRB000926 - Optical observations
  38. Re: GRB 000926, optical observation by Oksanen (vsnet-grb)
  39. J and K band observations of GRB 000926
  40. GRB000911 Optical Observations
  41. GRB 000926: Lightcurve Update and Predictions
  42. GRB 000926, optical observation by Oksanen (vsnet-grb)
  43. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  44. GRB000926: Optical observations
  45. CONCAM crude optical limits before and after GRB000926
  46. GRB 000926: Preliminary R-band Lightcurve
  47. GRB 000926 HST/Chandra TOO Status
  48. Spectroscopic Redshift of GRB 000926
  49. GRB 000926, Optical Observation
  50. GRB000926, radio observations
  51. GRB 000926: Optical candidate
  52. Optical candidate for GRB000926
  53. GRB 000911, BVRI field photometry
  54. GRB000911: Sub-millimeter observations
  55. GRB000911: Optical Transient
  56. GRB000911, Radio and Optical observations
  57. GRB000911: Optical observations
  58. GRB 000830: Optical observations
  59. GRB000830: Optical observations
  60. GRB000830, TNG B-band observations
  61. GRB000830, BVRI field photometry
  62. GRB000830: Optical observations
  63. GRB000210, Optical observations
  64. Chandra Position of GRB000210
  65. "Snapshot" afterglow IDs and GRB 000830
  66. GRB000830: Optical observations
  67. HST/STIS observations of the host galaxy of GRB 980329
  68. HST/STIS observations of the chaotic environment of GRB 980613
  69. GRB000812, TNG R-band observations
  70. GRB000801, VLT-Antu R-band observations
  71. GRB000301C, UBVI optical observations
  72. GRB 000727, optical observations
  73. GRB 990712: Late time HST/STIS Observations
  74. GRB000630, optical observations
  75. GRB 000630: Detection of the Optical Afterglow
  76. GRB000630, Optical Observations
  77. GRB000630, optical observations
  78. GRB000630, optical observations
  79. GRB000630, BVRI Field Photometry
  80. GRB000630, optical observations
  81. GRB000630, optical observations
  82. GRB000630: Optical observations
  83. GRB000630, Radio Observations
  84. possible optical counterpart of GRB 000630
  85. GRB 000623, optical observations
  86. GRB 000620, optical observations
  87. GRB000418, HST/STIS Observations
  88. GRB 990506, HST/STIS Observations of the Host Galaxy
  89. GRB000620, optical observations
  90. GRB990308, HST/STIS observations of the host galaxy
  91. GRB000620 - Optical observations
  92. GRB000620 Optical observations
  93. GRB000607, optical observations
  94. GRB990123, HST/STIS observations of the host galaxy
  95. GRB000616 optical observations
  96. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  97. GRB000615, further R-band photometry
  98. The Hosts of GRB 980703 and GRB 971214
  99. GRB 000301C: Further Late-Time HST/STIS observations
  100. Optical Follow-up of GRB000529 Error Box

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