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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"

43658 results found.

  1. GRB000604, optical observations
  2. GRB000528, optical observations at ESO
  3. GRB 000604 optical observations
  4. GRB 000418: Detection of the Host Galaxy
  5. GRB000604, optical observations, comparison with DPOSS
  6. GRB000604 [IPN Position]
  7. GRB000528, Radio Observations
  8. X-ray Afterglow of GRB 000529
  9. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  10. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  11. GRB000529: Optical Observations
  12. IPN localization and time history of GRB000528
  13. New IPN localization of GRB000529
  14. GRB000519: Optical observations
  15. GRB000529: BeppoSAX WFC position
  16. GRB000528: BeppoSAX GRBM observations
  17. GRB 000528 Optical Observations
  18. GRB000519, BVRI field photometry
  19. IPN triangulation of GRB000519
  20. IPN triangulation of GRB000516
  21. Re: GRB000508B : Optical observations
  22. GRB 000418, Optical observation
  23. GRB000508B, optical photometry
  24. GRB000508B, BVR field photometry
  25. Possible GRB-related phenomenon
  26. RXTE/ASM and IPN localization of GRB 000508B
  27. GRB000424, UBVRI field photometry
  28. GRB 000424 Optical Observations
  29. GRB000418, UBVRI field photometry update
  30. The redshift of GRB 000418
  31. GRB000424, optical observations
  32. GRB 000429, optical observation
  33. GRB 000429, UBVRI field photometry
  34. IPN localization of GRB000429
  35. GRB 000418, UBVRI field photometry
  36. GRB000418, Radio detection
  37. GRB000418, K'-band photometry
  38. GRB 000418, Optical Observation
  39. GRB 000418, optical observation
  40. GRB000424 Optical Observations
  41. GRB 000418, Optical Observation
  42. GRB000424, optical observations
  43. GRB 000424, Optical Observations
  44. GRB 000418, Optical Observation
  45. GRB000418, near-infrared observations
  46. BeppoSAX GRB000424
  47. Correction to IPN error box for GRB000419
  48. IPN error box for GRB000418
  49. GRB000419 [IPN Position]
  50. GRB000416 Optical Observations
  51. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  52. GRB000416 BRJK observations
  53. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  54. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  55. Budget cuts in BeppoSAX operations: impact on GRB observations
  56. GRB 000408, optical observations
  57. Refined IPN error box for GRB000408
  58. GRB 991208, UBVRI field photometry
  59. GRB000301c results
  60. GRB000408: Optical CCD Observations from MIRO
  61. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  62. GRB000408 [IPN Position]
  63. GRB000326 Optical Observations
  64. GRB000301C - Addendum to GCN 623
  65. GRB000301C - R magnitude lower limit
  66. GRB000326, Further VLA observations
  67. GRB 000323, optical observations
  68. GRB 000326: Optical Observations
  69. GRB000326, Radio observations
  70. GRB000326 [IPN Position]
  71. GRB 000307 optical observations
  72. GRB000323 [IPN Position]
  73. Single error box for GRB000315
  74. GRB000315 [IPN Positions]
  75. GRB000313, Radio observations
  76. GRB 000313 - optical transient in the BATSE error box
  77. GRB000301C - B and R photometry
  78. GRB000301C - R photometry
  79. GRB 000307, Optical Observations
  80. GRB 000307, BVRI Field Photometry
  81. GRB 000301C: Optical Spectrum and Redshift
  82. GRB 000301C: Optical Spectrum and Redshift
  83. GRB 000301C: A Precise Redshift Determination
  84. GRB 000301C, Optical Observation
  85. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  86. GRB 000301C: HST/STIS CCD Imaging of the field
  87. IPN error box for GRB000307
  88. GRB 000301c: K' observations
  89. GRB000301C, optical R-band observations
  90. GRB000301c - R photometry and nearby faint source confirmation
  91. GRB 000301C, Optical Observation
  92. GRB 000301c: K' observations
  93. GRB 000301C Optical Observations
  94. GRB 000301C: K' Observations
  95. GRB000301C OT candidate optical observations
  96. GRB000301C - Host galaxy not detected in R (?)
  97. Optical observations of GRB000301c
  98. GRB000301C, Radio observations
  99. GRB000301C, Radio observations
  100. GRB000301C optical observations

Advanced

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