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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"

35957 results found.

  1. GRB000607, Radio Observations
  2. GRB000604 - Optical observations
  3. GRB000607, A SHORT, HARD BURST
  4. GRB000604, optical observations
  5. GRB000528, optical observations at ESO
  6. GRB 000604 optical observations
  7. GRB 000418: Detection of the Host Galaxy
  8. GRB000604, optical observations, comparison with DPOSS
  9. GRB000604 [IPN Position]
  10. X-ray Afterglow of GRB 000529
  11. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  12. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  13. IPN localization and time history of GRB000528
  14. New IPN localization of GRB000529
  15. GRB 000528 - WFC measurements
  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. GRB 000429, optical observation
  32. GRB 000429, UBVRI field photometry
  33. IPN localization of GRB000429
  34. GRB 000418, UBVRI field photometry
  35. GRB000418, K'-band photometry
  36. GRB 000418, Optical Observation
  37. GRB 000418, optical observation
  38. GRB000424 Optical Observations
  39. GRB 000418, Optical Observation
  40. GRB 000424, Optical Observations
  41. GRB 000418, Optical Observation
  42. GRB000418, near-infrared observations
  43. Correction to IPN error box for GRB000419
  44. IPN error box for GRB000418
  45. GRB000419 [IPN Position]
  46. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  47. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  48. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  49. Budget cuts in BeppoSAX operations: impact on GRB observations
  50. GRB 000408, optical observations
  51. Refined IPN error box for GRB000408
  52. GRB 991208, UBVRI field photometry
  53. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  54. GRB000408 [IPN Position]
  55. GRB000326 Optical Observations
  56. GRB000301C - Addendum to GCN 623
  57. GRB000301C - R magnitude lower limit
  58. GRB 000323, optical observations
  59. GRB 000326: Optical Observations
  60. GRB000326, Radio observations
  61. GRB000326 [IPN Position]
  62. GRB 000307 optical observations
  63. GRB000323 [IPN Position]
  64. GRB000315 [IPN Positions]
  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 - Host galaxy not detected in R (?)
  85. GRB000301C optical observations
  86. GRB 000301c near-IR observations
  87. GRB 000301C, Optical Color
  88. GRB000301C, Optical Spectroscopy
  89. GRB 000301C, UBVRI field photometry
  90. GRB 000301C, Optical Observation
  91. GRB000301C 250 GHz detection
  92. GRB 000301C R-band observation
  93. GRB 000301C, Optical Observation
  94. GRB000301C, near-infrared observations (JHK' photometry)
  95. GRB 000301C: OT confirmed
  96. GRB000301c optical observations
  97. GRB 000301A, Radio Observations
  98. GRB000301C, optical observations
  99. GRB000301c, near-infrared observations
  100. GRB000301C

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