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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. GRB000529: BeppoSAX WFC position
  2. GRB000528: BeppoSAX GRBM observations
  3. GRB 000528 Optical Observations
  4. GRB000519, BVRI field photometry
  5. IPN triangulation of GRB000519
  6. IPN triangulation of GRB000516
  7. Re: GRB000508B : Optical observations
  8. GRB 000418, Optical observation
  9. GRB000508B, optical photometry
  10. GRB000508B, BVR field photometry
  11. Possible GRB-related phenomenon
  12. RXTE/ASM and IPN localization of GRB 000508B
  13. GRB000424, UBVRI field photometry
  14. GRB 000424 Optical Observations
  15. GRB000418, UBVRI field photometry update
  16. The redshift of GRB 000418
  17. GRB000424, optical observations
  18. GRB 000429, optical observation
  19. GRB 000429, UBVRI field photometry
  20. IPN localization of GRB000429
  21. GRB 000418, UBVRI field photometry
  22. GRB000418, Radio detection
  23. GRB000418, K'-band photometry
  24. GRB 000418, Optical Observation
  25. GRB 000418, optical observation
  26. GRB000424 Optical Observations
  27. GRB 000418, Optical Observation
  28. GRB000424, optical observations
  29. GRB000424, optical observations
  30. GRB 000424, Optical Observations
  31. GRB 000418, Optical Observation
  32. GRB000418, near-infrared observations
  33. BeppoSAX GRB000424
  34. Correction to IPN error box for GRB000419
  35. IPN error box for GRB000418
  36. GRB000419 [IPN Position]
  37. GRB000416 Optical Observations
  38. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  39. GRB000416 BRJK observations
  40. 1SAXJ1715.0-7134 refined position
  41. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  42. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  43. Budget cuts in BeppoSAX operations: impact on GRB observations
  44. GRB 000408, optical observations
  45. Refined IPN error box for GRB000408
  46. GRB 991208, UBVRI field photometry
  47. GRB000301c results
  48. GRB000408: Optical CCD Observations from MIRO
  49. GRB000408, lotis optical observations
  50. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  51. GRB000408 [IPN Position]
  52. GRB000326 Optical Observations
  53. GRB000301C - Addendum to GCN 623
  54. GRB000301C - R magnitude lower limit
  55. GRB000326, Further VLA observations
  56. GRB 000323, optical observations
  57. GRB 000326: Optical Observations
  58. GRB000326, Radio observations
  59. GRB000326 [IPN Position]
  60. GRB 000307 optical observations
  61. GRB000323 [IPN Position]
  62. Single error box for GRB000315
  63. GRB000315 [IPN Positions]
  64. GRB000313, Radio observations
  65. GRB 000313 - optical transient in the BATSE error box
  66. GRB000301C - B and R photometry
  67. GRB000301C - R photometry
  68. GRB 000307, Optical Observations
  69. GRB 000307, BVRI Field Photometry
  70. GRB 000301C: Optical Spectrum and Redshift
  71. GRB 000301C: Optical Spectrum and Redshift
  72. GRB 000301C: A Precise Redshift Determination
  73. GRB 000301C, Optical Observation
  74. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  75. GRB 000301C: HST/STIS CCD Imaging of the field
  76. IPN error box for GRB000307
  77. GRB 000301c: K' observations
  78. GRB000301C, optical R-band observations
  79. GRB000301c - R photometry and nearby faint source confirmation
  80. GRB 000301C, Optical Observation
  81. GRB 000301c: K' observations
  82. GRB 000301C Optical Observations
  83. GRB 000301C: K' Observations
  84. GRB000301C OT candidate optical observations
  85. GRB000301C - Host galaxy not detected in R (?)
  86. Optical observations of GRB000301c
  87. GRB000301C, Radio observations
  88. GRB000301C, Radio observations
  89. GRB000301C optical observations
  90. GRB000301C, near-infrared observations (JHK' imaging)
  91. GRB 000301c near-IR observations
  92. GRB 000301C, Optical Color
  93. GRB000301C, Optical Spectroscopy
  94. GRB 000301C, UBVRI field photometry
  95. GRB 000301C, Optical Observation
  96. GRB000301C, optical observations
  97. GRB000301C 250 GHz detection
  98. GRB 000301C R-band observation
  99. GRB 000301C, Optical Observation
  100. GRB000301C, near-infrared observations (JHK' photometry)

Advanced

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