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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"
  1. GRB000607, Radio Observations
  2. BeppoSAX X-ray transient/possible GRB000608
  3. GRB000604 optical non-detection
  4. GRB000604 - Optical observations
  5. GRB000607, A SHORT, HARD BURST
  6. GRB000604, optical observations
  7. GRB000528, optical observations at ESO
  8. GRB 000604 optical observations
  9. GRB 000418: Detection of the Host Galaxy
  10. GRB000604, optical observations, comparison with DPOSS
  11. GRB000604 [IPN Position]
  12. GRB000528, Radio Observations
  13. X-ray Afterglow of GRB 000529
  14. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  15. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  16. GRB000529: Optical Observations
  17. IPN localization and time history of GRB000528
  18. New IPN localization of GRB000529
  19. GRB000519: Optical observations
  20. IPN localization of GRB000529
  21. GRB 000528 - WFC measurements
  22. GRB000529: BeppoSAX WFC position
  23. GRB000528: BeppoSAX GRBM observations
  24. GRB 000528 Optical Observations
  25. GRB000519, BVRI field photometry
  26. IPN triangulation of GRB000519
  27. IPN triangulation of GRB000516
  28. Re: GRB000508B : Optical observations
  29. GRB 000418, Optical observation
  30. GRB000508B, optical photometry
  31. GRB000508B, BVR field photometry
  32. Possible GRB-related phenomenon
  33. RXTE/ASM and IPN localization of GRB 000508B
  34. GRB000424, UBVRI field photometry
  35. GRB 000424 Optical Observations
  36. GRB000418, UBVRI field photometry update
  37. The redshift of GRB 000418
  38. GRB000424, optical observations
  39. GRB 000429, optical observation
  40. GRB 000429, UBVRI field photometry
  41. IPN localization of GRB000429
  42. GRB 000418, UBVRI field photometry
  43. GRB000418, Radio detection
  44. GRB000418, K'-band photometry
  45. GRB 000418, Optical Observation
  46. GRB 000418, optical observation
  47. GRB000424 Optical Observations
  48. GRB 000418, Optical Observation
  49. GRB000424, optical observations
  50. GRB000424, optical observations
  51. GRB 000424, Optical Observations
  52. GRB 000418, Optical Observation
  53. GRB000418, near-infrared observations
  54. BeppoSAX GRB000424
  55. Correction to IPN error box for GRB000419
  56. IPN error box for GRB000418
  57. GRB000419 [IPN Position]
  58. GRB000416 Optical Observations
  59. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  60. GRB000416 BRJK observations
  61. 1SAXJ1715.0-7134 refined position
  62. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  63. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  64. Budget cuts in BeppoSAX operations: impact on GRB observations
  65. GRB 000408, optical observations
  66. Refined IPN error box for GRB000408
  67. GRB 991208, UBVRI field photometry
  68. GRB000301c results
  69. GRB000408: Optical CCD Observations from MIRO
  70. GRB000408, lotis optical observations
  71. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  72. GRB000408 [IPN Position]
  73. GRB000326 Optical Observations
  74. GRB000301C - Addendum to GCN 623
  75. GRB000301C - R magnitude lower limit
  76. GRB000326, Further VLA observations
  77. GRB 000323, optical observations
  78. GRB 000326: Optical Observations
  79. GRB000326, Radio observations
  80. GRB000326 [IPN Position]
  81. GRB 000307 optical observations
  82. GRB000323 [IPN Position]
  83. Single error box for GRB000315
  84. GRB000315 [IPN Positions]
  85. GRB000313, Radio observations
  86. GRB 000313 - optical transient in the BATSE error box
  87. GRB000301C - B and R photometry
  88. GRB000301C - R photometry
  89. GRB 000307, Optical Observations
  90. GRB 000307, BVRI Field Photometry
  91. GRB 000301C: Optical Spectrum and Redshift
  92. GRB 000301C: Optical Spectrum and Redshift
  93. GRB 000301C: A Precise Redshift Determination
  94. GRB 000301C, Optical Observation
  95. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  96. GRB 000301C: HST/STIS CCD Imaging of the field
  97. IPN error box for GRB000307
  98. GRB 000301c: K' observations
  99. GRB000301C, optical R-band observations
  100. GRB000301c - R photometry and nearby faint source confirmation

Advanced

Download all Circulars as a .tar.gz archive:
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