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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').

32054 results found.

  1. GRB 000604 optical observations
  2. GRB 000418: Detection of the Host Galaxy
  3. GRB000604, optical observations, comparison with DPOSS
  4. GRB000604 [IPN Position]
  5. X-ray Afterglow of GRB 000529
  6. GRB000529: BeppoSAX NFI follow-up preliminary analysis
  7. GRB000528: BeppoSAX NFI follow-up preliminary analysis
  8. IPN localization and time history of GRB000528
  9. New IPN localization of GRB000529
  10. GRB 000528 - WFC measurements
  11. GRB000528: BeppoSAX GRBM observations
  12. GRB 000528 Optical Observations
  13. GRB000519, BVRI field photometry
  14. IPN triangulation of GRB000519
  15. IPN triangulation of GRB000516
  16. Re: GRB000508B : Optical observations
  17. GRB 000418, Optical observation
  18. GRB000508B, optical photometry
  19. GRB000508B, BVR field photometry
  20. Possible GRB-related phenomenon
  21. RXTE/ASM and IPN localization of GRB 000508B
  22. GRB000424, UBVRI field photometry
  23. GRB 000424 Optical Observations
  24. GRB000418, UBVRI field photometry update
  25. The redshift of GRB 000418
  26. GRB 000429, optical observation
  27. GRB 000429, UBVRI field photometry
  28. IPN localization of GRB000429
  29. GRB 000418, UBVRI field photometry
  30. GRB000418, K'-band photometry
  31. GRB 000418, Optical Observation
  32. GRB 000418, optical observation
  33. GRB000424 Optical Observations
  34. GRB 000418, Optical Observation
  35. GRB 000424, Optical Observations
  36. GRB 000418, Optical Observation
  37. GRB000418, near-infrared observations
  38. Correction to IPN error box for GRB000419
  39. IPN error box for GRB000418
  40. GRB000419 [IPN Position]
  41. BATSE observations of FXT/GRB 000416 = 1SAXJ1715.0-7134
  42. RE: Budget cuts in BeppoSAX operations: impact on GRB observation
  43. X-ray burst or X-ray rich GRB 000416 observed by BeppoSAX
  44. Budget cuts in BeppoSAX operations: impact on GRB observations
  45. GRB 000408, optical observations
  46. Refined IPN error box for GRB000408
  47. GRB 991208, UBVRI field photometry
  48. GRB 000301C: Late-Time HST/STIS CCD Imaging of the field
  49. GRB000408 [IPN Position]
  50. GRB000326 Optical Observations
  51. GRB000301C - Addendum to GCN 623
  52. GRB000301C - R magnitude lower limit
  53. GRB 000323, optical observations
  54. GRB 000326: Optical Observations
  55. GRB000326, Radio observations
  56. GRB000326 [IPN Position]
  57. GRB 000307 optical observations
  58. GRB000323 [IPN Position]
  59. GRB000315 [IPN Positions]
  60. GRB 000313 - optical transient in the BATSE error box
  61. GRB000301C - B and R photometry
  62. GRB000301C - R photometry
  63. GRB 000307, Optical Observations
  64. GRB 000307, BVRI Field Photometry
  65. GRB 000301C: Optical Spectrum and Redshift
  66. GRB 000301C: Optical Spectrum and Redshift
  67. GRB 000301C: A Precise Redshift Determination
  68. GRB 000301C, Optical Observation
  69. GRB 000301C: HST/STIS-PRISM NUV-MAMA spectroscopy
  70. GRB 000301C: HST/STIS CCD Imaging of the field
  71. IPN error box for GRB000307
  72. GRB 000301c: K' observations
  73. GRB000301C, optical R-band observations
  74. GRB000301c - R photometry and nearby faint source confirmation
  75. GRB 000301C, Optical Observation
  76. GRB 000301c: K' observations
  77. GRB 000301C Optical Observations
  78. GRB 000301C: K' Observations
  79. GRB000301C - Host galaxy not detected in R (?)
  80. GRB000301C optical observations
  81. GRB 000301c near-IR observations
  82. GRB 000301C, Optical Color
  83. GRB000301C, Optical Spectroscopy
  84. GRB 000301C, UBVRI field photometry
  85. GRB 000301C, Optical Observation
  86. GRB000301C 250 GHz detection
  87. GRB 000301C R-band observation
  88. GRB 000301C, Optical Observation
  89. GRB000301C, near-infrared observations (JHK' photometry)
  90. GRB 000301C: OT confirmed
  91. GRB000301c optical observations
  92. GRB 000301A, Radio Observations
  93. GRB000301C, optical observations
  94. GRB000301c, near-infrared observations
  95. GRB000301C
  96. GRB 000301C : Optical Candidate
  97. GRB000301C: RXTE/ASM and IPN localizations
  98. GRB000226 [IPN Position]
  99. HST Observations of GRB 990712
  100. GRB 000214 near-IR observations

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