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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').

17991 results found.

  1. GRB ALERT: GRB991105
  2. GRB 991014 - X-ray afterglow identification by BeppoSAX-NFI
  3. GRB 991014, Optical Observations
  4. GRB 991014 - BeppoSAX NFI observations
  5. GRB 991014, radio observations
  6. GRB 991014, Optical Observations
  7. GRB 991014, optical observations
  8. Super-LOTIS optical observation of GRB991014
  9. Optical Observations of GRB990907
  10. GRB990907 and 990908
  11. GRB990806 BeppoSAX follow up
  12. GRB 990806 Optical observations
  13. Optical Observations of GRB990806
  14. GRB 990806, Optical Observations
  15. GRB 990806, optical observations
  16. GRB 990806, Optical Observations
  17. GRB 990712 Optical Observations
  18. GRB 990712 Optical Decay: Indication of Bright Host Galaxy
  19. GRB 990712
  20. Late-time HST/STIS Observations of GRB 990510
  21. Refined BeppoSAX-WFC position of GRB990712
  22. BeppoSAX NFI Observation of GRB990705
  23. BeppoSAX NFI Observation of GRB990705
  24. Updated Astrometry for the IR Counterpart of GRB990705
  25. GRB 990705, R-band observations
  26. Infrared and Optical Observations of GRB990705
  27. GRB 990705, radio observations
  28. GRB990704: SAX-NFI results summary
  29. GRB990704 radio and optical observations
  30. GRB990704
  31. GRB990704, optical observations
  32. GRB 990627, radio observations
  33. Late-time HST/STIS Observation of GRB 990123
  34. Optical Observations of GRB 990506
  35. GRB990527 Optical Observations
  36. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  37. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  38. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  39. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  40. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  41. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  42. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  43. radio observations of X-ray/GRB transient field
  44. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  45. Optical report on X-ray/GRB transient
  46. GRB 990510: optical linear polarization
  47. GRB 990510: optical observations
  48. GRB990510, VI observations
  49. GRB 990510: BATSE Observations
  50. GRB 990510: BeppoSAX/GRBM observations
  51. GRB 990510 optical observations
  52. GRB 990506 Radio Observations
  53. GRB 990123, optical monitoring
  54. GRB 990506, optical observations
  55. GRB 990506, Optical Observations
  56. GRB 990506 optical observations
  57. GRB 990506, optical observations
  58. GRB 990506, optical observations from +1 to +3 hours
  59. GRB 990506, optical observations
  60. GRB990506 observation plan
  61. GRB981220 VLBA observations
  62. GRB 990316 Optical Observations
  63. GRB 990316 optical observations
  64. GRB990316: simultaneous optical observation
  65. GRB990316 - Optical null results
  66. GRB 990123, Field Photometry
  67. GRB 990217 Optical Observations
  68. GRB 990217, radio observations
  69. BATSE Flight Anomaly
  70. GRB990123 observations
  71. GRB990123, Optical Observation
  72. GRB 990123: Discovery of the Probable Host Galaxy
  73. GRB 990123: Reduced HST Images
  74. GRB19990123 observations
  75. GRB 990123: BVRI standards in the field
  76. GRB981220, field photometry
  77. GRB990123, Optical observation
  78. GRB990123, 15-GHz limits
  79. GRB 990123: New Constraints on Possible Foreground Galaxies
  80. GRB990123 Optical Observations
  81. GRB990123, Probability of gravitational lensing
  82. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  83. GRB990123, Preliminary Lens Search Results
  84. GRB990123, Optical BVRI Observations
  85. GRB 990123: near-infrared observations.
  86. GRB990123, OSSE observations
  87. GRB990123: NIR Observation
  88. "GRB 990123: New BV Observations"
  89. GRB 990123: New Optical Observations, Decay Measure
  90. GRB 990123 Optical Follow-Up
  91. GRB 990123: Possible Gravitationally Lensed Burst?
  92. GRB990123, optical observation
  93. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  94. GRB 990123 r-band photometry
  95. GRB 990123 Optical Follow-up
  96. GRB990123, early optical counterpart detection
  97. GRB 990123, Radio observations
  98. GRB990123, BeppoSAX WFC detection and NFI planned follow-up
  99. Possible identification of SN1999E with GRB980910
  100. Optical Observations of GRB 981220

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