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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"

45444 results found.

  1. GRB000424 Optical Observations
  2. GRB 000418, Optical Observation
  3. GRB000424, optical observations
  4. GRB000424, optical observations
  5. GRB 000424, Optical Observations
  6. GRB 000418, Optical Observation
  7. GRB000418, near-infrared observations
  8. BeppoSAX GRB000424
  9. Correction to IPN error box for GRB000419
  10. IPN error box for GRB000418
  11. GRB000419 [IPN Position]
  12. GRB000416 Optical Observations
  13. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  14. GRB000416 BRJK observations
  15. 1SAXJ1715.0-7134 refined position
  16. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  17. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  18. Budget cuts in BeppoSAX operations: impact on GRB observations
  19. GRB 000408, optical observations
  20. Refined IPN error box for GRB000408
  21. GRB 991208, UBVRI field photometry
  22. GRB000301c results
  23. GRB000408: Optical CCD Observations from MIRO
  24. GRB000408, lotis optical observations
  25. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  26. GRB000408 [IPN Position]
  27. GRB000326 Optical Observations
  28. GRB000301C - Addendum to GCN 623
  29. GRB000301C - R magnitude lower limit
  30. GRB000326, Further VLA observations
  31. GRB 000323, optical observations
  32. GRB 000326: Optical Observations
  33. GRB000326, Radio observations
  34. GRB000326 [IPN Position]
  35. GRB 000307 optical observations
  36. GRB000323 [IPN Position]
  37. Single error box for GRB000315
  38. GRB000315 [IPN Positions]
  39. GRB000313, Radio observations
  40. GRB 000313 - optical transient in the BATSE error box
  41. GRB000301C - B and R photometry
  42. GRB000301C - R photometry
  43. GRB 000307, Optical Observations
  44. GRB 000307, BVRI Field Photometry
  45. GRB 000301C: Optical Spectrum and Redshift
  46. GRB 000301C: Optical Spectrum and Redshift
  47. GRB 000301C: A Precise Redshift Determination
  48. GRB 000301C, Optical Observation
  49. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  50. GRB 000301C: HST/STIS CCD Imaging of the field
  51. IPN error box for GRB000307
  52. GRB 000301c: K' observations
  53. GRB000301C, optical R-band observations
  54. GRB000301c - R photometry and nearby faint source confirmation
  55. GRB 000301C, Optical Observation
  56. GRB 000301c: K' observations
  57. GRB 000301C Optical Observations
  58. GRB 000301C: K' Observations
  59. GRB000301C OT candidate optical observations
  60. GRB000301C - Host galaxy not detected in R (?)
  61. Optical observations of GRB000301c
  62. GRB000301C, Radio observations
  63. GRB000301C, Radio observations
  64. GRB000301C optical observations
  65. GRB000301C, near-infrared observations (JHK' imaging)
  66. GRB 000301c near-IR observations
  67. GRB 000301C, Optical Color
  68. GRB000301C, Optical Spectroscopy
  69. GRB 000301C, UBVRI field photometry
  70. GRB 000301C, Optical Observation
  71. GRB000301C, optical observations
  72. GRB000301C 250 GHz detection
  73. GRB 000301C R-band observation
  74. GRB 000301C, Optical Observation
  75. GRB000301C, near-infrared observations (JHK' photometry)
  76. GRB 000301C: OT confirmed
  77. GRB000301c optical observations
  78. GRB 000301A, Radio Observations
  79. GRB000301C, optical observations
  80. GRB000301c, near-infrared observations
  81. GRB000301C
  82. GRB 000301C : Optical Candidate
  83. Radio observations of the error box of GRB000301A
  84. GRB000301C: RXTE/ASM and IPN localizations
  85. GRB000226 [IPN Position]
  86. HST Observations of GRB 990712
  87. GRB 000214 near-IR observations
  88. GRB 000115 Optical observations
  89. GRB 000214, Radio Observations
  90. GRB 000214 ``Valentine's Day Burst'': BeppoSAX NFI Observation
  91. GRB000210, Radio Observations
  92. Correction to GCN 557 (GRB000214: BeppoSAX GRBM and WFC Detection)
  93. GRB 000115, BVRI field photometry
  94. GRB000214: BeppoSAX GRBM and WFC Detection
  95. IPN annulus for GRB000214
  96. Optical observations of GRB000210
  97. GRB000210 X-ray afterglow
  98. GRB000214: X-ray afterglow candidate
  99. GRB000214 refined BeppoSAX-WFC position
  100. BeppoSAX GRB000214 ("S. Valentine's day GRB")

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