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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').

31197 results found.

  1. BeppoSAX: GRB990625
  2. Late-time HST/STIS Observation of GRB 990123
  3. GRB 990506 - clarification to GCN 352
  4. GRB 990506 - Optical Observations
  5. Optical Observations of GRB 990506
  6. GRB 990506 Radio Transient
  7. GRB990527 Optical Observations
  8. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  9. IPN error box for GRB990527
  10. Late Afterglows of GRBs 990510, 990123
  11. X-ray/GRB 1SAX J0835.9+5118, TNG V and R observations
  12. X-ray/GRB 1SAX J0835.9+5118, BATSE Observation
  13. X-ray/GRB 1SAX J0835.9+5118, Optical Observations
  14. GRB 990506 optical observation
  15. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  16. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  17. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  18. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  19. radio observations of X-ray/GRB transient field
  20. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  21. Optical report on X-ray/GRB transient
  22. radio detection of X-ray/GRB transient
  23. BeppoSAX: A new fast X-ray transient
  24. GRB 990510: optical observations
  25. GRB990510: photometric and spectroscopic observations with the VLT
  26. GRB 990510: optical linear polarization
  27. GRB 990510: optical observations
  28. GRB990510, VI observations
  29. GRB 990506 R band observations
  30. GRB990510: X-ray afterglow
  31. GRB 990510: optical observation
  32. VLT spectrum of GRB990510
  33. GRB 990510: Broad Band Break
  34. GRB 990510: BATSE Observations
  35. GRB990510: optical observation
  36. GRB 990510 Optical Observations
  37. GRB 990510, BVI photometry
  38. GRB 990510 optical observations
  39. GRB 990510: BeppoSAX/GRBM observations
  40. GRB990510 optical observations
  41. GRB 990510 optical observations
  42. GRB 990510 optical observations
  43. Galactic extinction towards GRB 990510
  44. GRB 990510 optical observations
  45. IPN localization of GRB990510
  46. GRB 990506 Radio Observations
  47. GRB 990123, optical monitoring
  48. GRB 990506: BATSE Observations
  49. GRB 990506, optical observations
  50. GRB 990510: Final BeppoSAX-WFC Coordinates
  51. GRB 990506, Optical Observations
  52. GRB 990506 optical observations
  53. GRB 990506 optical observations
  54. GRB 990506, optical observations
  55. GRB990506 observation plan
  56. Refined IPN error box for GRB990506
  57. GRB 990506: Limits on the possible optical transient
  58. GRB 990506, armchair astronomy
  59. GRB 990506, optical observations from +1 to +3 hours
  60. GRB 990506, optical observations
  61. GRB990506 observation plan
  62. New IPN/RXTE error box for GRB990506
  63. IPN localization for GRB990506
  64. GRB 970228: Redshift and properties of the host galaxy
  65. IPN localization of GRB990427
  66. GRB981220 VLBA observations
  67. GRB990321 REFINED IPN ANNULUS
  68. GRB990323 PRECISE IPN POSITION
  69. GRB990321 IPN TRIANGULATION
  70. GRB 990316 Optical Observations
  71. GRB 990316, Radio observations
  72. GRB 990316, Optical observations
  73. GRB990316, Optical observations
  74. GRB 990316 optical observations
  75. GRB990316: simultaneous optical observation
  76. ASM/IPN error box for GRB 990308 (BATSE #7457)
  77. GRB990308 not a new SGR
  78. GRB 990308a and GRB 990308b
  79. GRB990308 (Trig. 7457), optical observations
  80. GRB981220, IPN localization
  81. GRB 981220, radio observations
  82. GRB 990123, Field Photometry
  83. GRB 990217 Optical Observations
  84. GRB 990217, radio observations
  85. Optical Observations of GRB990217
  86. GRB990123: Caltech STIS Photometry and Images
  87. GRB990123 observations
  88. GRB990123, Optical Observation
  89. GRB 990123: Discovery of the Probable Host Galaxy
  90. GRB 990123: Reduced HST Images
  91. For Immediate Posting to GCN - HST Data GRB 990123 Available
  92. GRB19990123 observations
  93. GRB 990123: BVRI standards in the field
  94. GRB 990123: Updated Keck Spectroscopy Results
  95. GRB981220, field photometry
  96. GRB 990123 NOT Spectrum Update
  97. GRB990123, Optical observation
  98. GRB990123, is the "radio flare" due to an inhomogeneous medium?
  99. GRB 990123: Publicly available reduced HST images
  100. GRB990123, Upcoming HST Service Observations

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