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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').

23918 results found.

  1. GRB990907 and 990908
  2. GRB 990712 Late Optical Decay and Host Galaxy
  3. GRB990806 BeppoSAX follow up
  4. GRB990806: BATSE Observations
  5. GRB 990806 Optical observations
  6. GRB 990806, Optical Observations
  7. GRB 990806, optical observations
  8. GRB 990806, Optical Observations
  9. GRB990806 UBVRIJHK observations
  10. GRB 990712 Optical Observations
  11. GRB 990712
  12. Late-time HST/STIS Observations of GRB 990510
  13. BeppoSAX NFI Observation of GRB990705
  14. BeppoSAX NFI Observation of GRB990705
  15. GRB 990705, R-band observations
  16. Infrared and Optical Observations of GRB990705
  17. GRB990704: SAX-NFI results summary
  18. GRB990704 radio and optical observations
  19. GRB990704
  20. GRB990704, optical observations
  21. BeppoSAX NFI Observation of GRB990627 X-ray afterglow
  22. Optical Observations of GRB990627
  23. BeppoSAX: GRB990625
  24. Late-time HST/STIS Observation of GRB 990123
  25. Optical Observations of GRB 990506
  26. GRB990527 Optical Observations
  27. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  28. Late Afterglows of GRBs 990510, 990123
  29. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  30. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  31. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  32. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  33. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  34. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  35. radio observations of X-ray/GRB transient field
  36. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  37. Optical report on X-ray/GRB transient
  38. radio detection of X-ray/GRB transient
  39. BeppoSAX: A new fast X-ray transient
  40. GRB 990510: optical observations
  41. GRB 990510: optical linear polarization
  42. GRB 990510: optical observations
  43. GRB990510: X-ray afterglow
  44. GRB 990510: Broad Band Break
  45. GRB 990510: BATSE Observations
  46. GRB 990510: BeppoSAX/GRBM observations
  47. GRB990510 optical observations
  48. GRB 990510 optical observations
  49. GRB 990506 Radio Observations
  50. GRB 990123, optical monitoring
  51. GRB 990506: BATSE Observations
  52. GRB 990506, optical observations
  53. GRB 990506, Optical Observations
  54. GRB 990506 optical observations
  55. GRB 990506, optical observations
  56. GRB 990506, armchair astronomy
  57. GRB 990506, optical observations from +1 to +3 hours
  58. GRB 990506, optical observations
  59. GRB990506 observation plan
  60. IPN localization for GRB990506
  61. GRB990323 PRECISE IPN POSITION
  62. GRB 990316 Optical Observations
  63. GRB 990316 optical observations
  64. GRB990316: simultaneous optical observation
  65. GRB990316 - Optical null results
  66. GRB990308 not a new SGR
  67. GRB 990308a and GRB 990308b
  68. GRB990308, Possible new SGR~0209+70
  69. GRB 990123, Field Photometry
  70. GRB 990217 Optical Observations
  71. BATSE Flight Anomaly
  72. GRB990217: BeppoSAX/GRBM data
  73. GRB990123 observations
  74. GRB990217 Optical observation
  75. GRB990123, Optical Observation
  76. GRB 990123: Discovery of the Probable Host Galaxy
  77. GRB 990123: Reduced HST Images
  78. GRB19990123 observations
  79. GRB 990123: BVRI standards in the field
  80. GRB981220, field photometry
  81. GRB990123, Optical observation
  82. GRB990123, 15-GHz limits
  83. GRB 990123: New Constraints on Possible Foreground Galaxies
  84. GRB990123 Optical Observations
  85. GRB990123, Probability of gravitational lensing
  86. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  87. GRB990123, Preliminary Lens Search Results
  88. On the Lensing Interpretation of GRB 990123
  89. Search for Potential Images of GRB 990123
  90. Search for Potential Images of GRB 990123
  91. GRB990123, Optical BVRI Observations
  92. GRB 990123: near-infrared observations.
  93. GRB990123, OSSE observations
  94. GRB990123: NIR Observation
  95. GRB990123, ASCA X-ray observation of afterglow
  96. "GRB 990123: New BV Observations"
  97. GRB 990123 Optical Follow-Up
  98. GRB 990123: BATSE Observations
  99. GRB990123 Optical Observations
  100. GRB 990123: New Optical Observations, Decay Measure

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