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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.

Lucene Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

19139 results found.

  1. GRB000926 - Optical observations
  2. GRB 000926: optical observations
  3. GRB 000926, Optical Observations
  4. GRB000926 - Optical observations
  5. GRB000911: optical VLT observations
  6. GRB000926 K'-band Observation
  7. GRB000926 optical observations
  8. GRB000926 - Optical observations
  9. J and K band observations of GRB 000926
  10. GRB000911 Optical Observations
  11. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  12. GRB000926: Optical observations
  13. GRB 000926 HST/Chandra TOO Status
  14. GRB000926, radio observations
  15. GRB 000926: Optical candidate
  16. GRB000911: Sub-millimeter observations
  17. GRB000911, Radio and Optical observations
  18. GRB000911, Radio observations
  19. GRB000911: Optical observations
  20. GRB 000830: Optical observations
  21. GRB000830: Optical observations
  22. GRB000830, TNG B-band observations
  23. GRB000830: Optical observations
  24. GRB000210, Optical observations
  25. "Snapshot" afterglow IDs and GRB 000830
  26. GRB000830: Optical observations
  27. HST/STIS observations of the host galaxy of GRB 980329
  28. HST/STIS observations of the chaotic environment of GRB 980613
  29. SGR 1806-20 burst activity
  30. GRB000812, TNG R-band observations
  31. GRB000801 & GRB000730, Gamma Ray Observations
  32. GRB000730, Gamma Ray Observations
  33. GRB000812, Radio observations
  34. GRB000801, Gamma Ray Observations
  35. GRB000801, VLT-Antu R-band observations
  36. GRB000301C, UBVI optical observations
  37. GRB000801, Radio Observations
  38. GRB 991208 Host Galaxy Imaging
  39. GRB 990510: Possible detection of a host galaxy
  40. GRB 990510 Host Galaxy Discovery
  41. GRB 000727, optical observations
  42. GRB 990705, HST/STIS observations of the host galaxy
  43. GRB 990712: Late time HST/STIS Observations
  44. GRB 991216, HST/STIS observations
  45. GRB000620, Radio Observations
  46. GRB981226, HST/STIS observations of the host galaxy
  47. GRB000630, optical observations
  48. GRB 000630: Detection of the Optical Afterglow
  49. GRB000630, Optical Observations
  50. GRB000630, optical observations
  51. GRB000630, optical observations
  52. GRB000630, optical observations
  53. GRB000630, optical observations
  54. GRB000630: Optical observations
  55. GRB000630, Radio Observations
  56. possible optical counterpart of GRB 000630
  57. GRB 000623, optical observations
  58. GRB 000620, optical observations
  59. GRB000418, HST/STIS Observations
  60. GRB990123: Late-time HST/STIS observations of the host
  61. GRB 990506, HST/STIS Observations of the Host Galaxy
  62. GRB 000620: J-band observations
  63. GRB000620, optical observations
  64. GRB000615: H-band observations
  65. GRB990308, HST/STIS observations of the host galaxy
  66. GRB000620 - Optical observations
  67. GRB000620 Optical observations
  68. GRB000615, Radio observations
  69. GRB000607, optical observations
  70. GRB 000615: NIR further observations
  71. GRB990123, HST/STIS observations of the host galaxy
  72. GRB000616 optical observations
  73. GRB 000615, near-infrared observations
  74. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  75. GRB000615, further R-band photometry
  76. GRB 000615: NIR observations
  77. GRB000615, R-band photometry
  78. GRB980425, HST/STIS observations of the host galaxy
  79. The Hosts of GRB 980703 and GRB 971214
  80. GRB 000301C: Further Late-Time HST/STIS observations
  81. GRB980519, HST/STIS observations of the host galaxy
  82. GRB000607, Radio Observations
  83. GRB000604 - Optical observations
  84. GRB000604, optical observations
  85. GRB000528, optical observations at ESO
  86. GRB 000604 optical observations
  87. GRB 000418: Detection of the Host Galaxy
  88. GRB000604, optical observations, comparison with DPOSS
  89. GRB000528, Radio Observations
  90. GRB000529: Optical Observations
  91. GRB000519: Optical observations
  92. GRB000528: BeppoSAX GRBM observations
  93. GRB 000528 Optical Observations
  94. Re: GRB000508B : Optical observations
  95. GRB 000418, Optical observation
  96. GRB000508B, optical photometry
  97. Possible GRB-related phenomenon
  98. GRB 000424 Optical Observations
  99. GRB000418, UBVRI field photometry update
  100. The redshift of GRB 000418

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