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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"

23409 results found.

  1. GRB000812, TNG R-band observations
  2. IPN localization of GRB000812
  3. IPN localization of GRB000811
  4. GRB000801, VLT-Antu R-band observations
  5. GRB 991208 Host Galaxy Imaging
  6. IPN localization of GRB000801
  7. IPN localization of GRB000730B
  8. IPN localization of GRB000730B
  9. IPN localization of GRB000730
  10. GRB 990510: Possible detection of a host galaxy
  11. GRB 990510 Host Galaxy Discovery
  12. IPN localization of GRB000727
  13. GRB 990712: Late time HST/STIS Observations
  14. GRB 991216, HST/STIS observations
  15. GRB000630, optical observations
  16. GRB000630, Revised BVRI Field Photometry
  17. GRB000630, Optical Observations
  18. GRB000630, optical observations
  19. GRB000630, optical observations
  20. GRB000630, BVRI Field Photometry
  21. GRB000630, optical observations
  22. GRB000630: Optical observations
  23. possible optical counterpart of GRB 000630
  24. IPN triangulation of GRB000630
  25. GRB 000620, optical observations
  26. GRB000418, HST/STIS Observations
  27. GRB990123: Late-time HST/STIS observations of the host
  28. GRB000623
  29. GRB000620, optical observations
  30. GRB000615: H-band observations
  31. GRB000620 - Optical observations
  32. GRB000620 Optical observations
  33. IPN annulus for GRB000620
  34. GRB000620: BeppoSAX WFC and GRBM detection
  35. GRB000607, optical observations
  36. GRB 000615: NIR further observations
  37. GRB990123, HST/STIS observations of the host galaxy
  38. GRB000616 optical observations
  39. GRB 990123: Late-time HST/STIS 50CCD observations of the host
  40. GRB000616 [IPN Position]
  41. GRB000615B [IPN Position]
  42. GRB000615, further R-band photometry
  43. GRB 000615: NIR observations
  44. GRB000615: BeppoSAX NFI follow-up preliminary analysis
  45. GRB000615, R-band photometry
  46. GRB 000301C: Further Late-Time HST/STIS observations
  47. GRB000528: follow-up X-ray measurements and update of IPN annulus
  48. Optical Follow-up of GRB000529 Error Box
  49. GRB000604 optical non-detection
  50. GRB000604 - Optical observations
  51. GRB000607, A SHORT, HARD BURST
  52. GRB000604, optical observations
  53. GRB000528, optical observations at ESO
  54. GRB 000604 optical observations
  55. GRB 000418: Detection of the Host Galaxy
  56. GRB000604, optical observations, comparison with DPOSS
  57. GRB000604 [IPN Position]
  58. GRB000528, Radio Observations
  59. X-ray Afterglow of GRB 000529
  60. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  61. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  62. GRB000529: Optical Observations
  63. IPN localization and time history of GRB000528
  64. IPN localization of GRB000529
  65. GRB 000528 - WFC measurements
  66. GRB000519, BVRI field photometry
  67. IPN triangulation of GRB000519
  68. IPN triangulation of GRB000516
  69. Re: GRB000508B : Optical observations
  70. GRB000508B, optical photometry
  71. GRB000508B, BVR field photometry
  72. Possible GRB-related phenomenon
  73. RXTE/ASM and IPN localization of GRB 000508B
  74. GRB000424, UBVRI field photometry
  75. GRB 000424 Optical Observations
  76. GRB000418, UBVRI field photometry update
  77. GRB000424, optical observations
  78. GRB 000429, optical observation
  79. GRB 000429, UBVRI field photometry
  80. IPN localization of GRB000429
  81. GRB 000418, UBVRI field photometry
  82. GRB 000418, optical observation
  83. GRB000424, optical observations
  84. GRB 000418, Optical Observation
  85. IPN error box for GRB000418
  86. GRB000419 [IPN Position]
  87. GRB000416 Optical Observations
  88. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  89. Budget cuts in BeppoSAX operations: impact on GRB observations
  90. GRB 000408, optical observations
  91. GRB 991208, UBVRI field photometry
  92. GRB000408, lotis optical observations
  93. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  94. GRB000301C - Addendum to GCN 623
  95. GRB 000326: Optical Observations
  96. GRB000326, Radio observations
  97. GRB 000307 optical observations
  98. Single error box for GRB000315
  99. GRB000315 [IPN Positions]
  100. GRB000313, Radio observations

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Download all Circulars as a .tar.gz archive (updated once a day):
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