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

Advanced

Download all Circulars as a .tar.gz archive:
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