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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"

25779 results found.

  1. GRB000926: X-ray afterglow by BeppoSAX & plan of BSAX & Chandra obs.
  2. CONCAM crude optical limits before and after GRB000926
  3. Spectroscopic Redshift of GRB 000926
  4. GRB 000926: Optical candidate
  5. Optical candidate for GRB000926
  6. IPN triangulation of GRB000926
  7. GRB 000911, BVRI field photometry
  8. IPN triangulation of GRB000925
  9. GRB000911, Radio and Optical observations
  10. GRB000911: Optical observations
  11. IPN triangulation of GRB000911
  12. IPN triangulation of GRB000910
  13. GRB000830, BVRI field photometry
  14. IPN triangulation of GRB000830
  15. HST/STIS observations of the host galaxy of GRB 980329
  16. IPN localization of GRB000820
  17. SGR 1806-20 burst activity
  18. GRB000801 & GRB000730, Gamma Ray Observations
  19. GRB000730, Gamma Ray Observations
  20. IPN localization of GRB000812
  21. IPN localization of GRB000811
  22. GRB000801, Gamma Ray Observations
  23. GRB000801, VLT-Antu R-band observations
  24. GRB 991208 Host Galaxy Imaging
  25. IPN localization of GRB000801
  26. IPN localization of GRB000730B
  27. IPN localization of GRB000730B
  28. IPN localization of GRB000730
  29. GRB 990510: Possible detection of a host galaxy
  30. GRB 990510 Host Galaxy Discovery
  31. IPN localization of GRB000727
  32. GRB 990705, HST/STIS observations of the host galaxy
  33. GRB 990712: Late time HST/STIS Observations
  34. GRB 991216, HST/STIS observations
  35. GRB000630, optical observations
  36. GRB000630, Revised BVRI Field Photometry
  37. GRB000630, Optical Observations
  38. GRB000630, optical observations
  39. GRB000630, optical observations
  40. GRB000630, BVRI Field Photometry
  41. GRB000630, optical observations
  42. GRB000630: Optical observations
  43. possible optical counterpart of GRB 000630
  44. IPN triangulation of GRB000630
  45. GRB 000620, optical observations
  46. GRB000418, HST/STIS Observations
  47. GRB990123: Late-time HST/STIS observations of the host
  48. GRB 990506, HST/STIS Observations of the Host Galaxy
  49. GRB000623
  50. GRB 000620: J-band observations
  51. GRB000620, optical observations
  52. GRB990308, HST/STIS observations of the host galaxy
  53. GRB000620 - Optical observations
  54. GRB000620 Optical observations
  55. GRB000620: BeppoSAX WFC and GRBM detection
  56. GRB000607, optical observations
  57. GRB 000615: NIR further observations
  58. GRB990123, HST/STIS observations of the host galaxy
  59. GRB000616 optical observations
  60. GRB 000615, near-infrared observations
  61. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  62. GRB000616 [IPN Position]
  63. GRB000615B [IPN Position]
  64. GRB000615, further R-band photometry
  65. GRB 000615: NIR observations
  66. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  67. GRB000615, R-band photometry
  68. GRB000615: BeppoSAX refined coordinates
  69. GRB980425, HST/STIS observations of the host galaxy
  70. GRB 000301C: Further Late-Time HST/STIS observations
  71. GRB000528: follow-up X-ray measurements and update of IPN annulus
  72. BeppoSAX X-ray transient/possible GRB000608
  73. GRB000604 - Optical observations
  74. GRB000607, A SHORT, HARD BURST
  75. GRB000604, optical observations
  76. GRB000528, optical observations at ESO
  77. GRB 000418: Detection of the Host Galaxy
  78. GRB000604, optical observations, comparison with DPOSS
  79. GRB000604 [IPN Position]
  80. GRB000528, Radio Observations
  81. X-ray Afterglow of GRB 000529
  82. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  83. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  84. GRB 000528 - WFC measurements
  85. GRB000529: BeppoSAX WFC position
  86. GRB000528: BeppoSAX GRBM observations
  87. GRB 000528 Optical Observations
  88. GRB000519, BVRI field photometry
  89. IPN triangulation of GRB000519
  90. IPN triangulation of GRB000516
  91. GRB000508B, optical photometry
  92. GRB000508B, BVR field photometry
  93. Possible GRB-related phenomenon
  94. RXTE/ASM and IPN localization of GRB 000508B
  95. GRB000424, UBVRI field photometry
  96. GRB000418, UBVRI field photometry update
  97. The redshift of GRB 000418
  98. GRB000424, optical observations
  99. GRB 000429, optical observation
  100. GRB 000429, UBVRI field photometry

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