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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. 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"

35996 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. GRB 990510 Optical Observations
  36. GRB 990510, BVI photometry
  37. GRB 990510 optical observations
  38. GRB 990510: BeppoSAX/GRBM observations
  39. GRB990510 optical observations
  40. GRB 990510 optical observations
  41. GRB 990510 optical observations
  42. Galactic extinction towards GRB 990510
  43. GRB 990510 optical observations
  44. IPN localization of GRB990510
  45. GRB 990506 Radio Observations
  46. GRB 990123, optical monitoring
  47. GRB 990506: BATSE Observations
  48. GRB 990506, optical observations
  49. GRB 990510: Final BeppoSAX-WFC Coordinates
  50. GRB 990506, Optical Observations
  51. GRB 990506 optical observations
  52. GRB 990506 optical observations
  53. GRB 990506, optical observations
  54. GRB990506 observation plan
  55. Refined IPN error box for GRB990506
  56. GRB 990506: Limits on the possible optical transient
  57. GRB 990506, armchair astronomy
  58. GRB 990506, optical observations from +1 to +3 hours
  59. GRB 990506, optical observations
  60. GRB990506 observation plan
  61. New IPN/RXTE error box for GRB990506
  62. IPN localization for GRB990506
  63. GRB 970228: Redshift and properties of the host galaxy
  64. IPN localization of GRB990427
  65. GRB981220 VLBA observations
  66. GRB990321 REFINED IPN ANNULUS
  67. GRB990323 PRECISE IPN POSITION
  68. GRB990321 IPN TRIANGULATION
  69. GRB 990316 Optical Observations
  70. GRB 990316, Radio observations
  71. GRB 990316, Optical observations
  72. GRB990316, Optical observations
  73. GRB 990316 optical observations
  74. GRB990316: simultaneous optical observation
  75. ASM/IPN error box for GRB 990308 (BATSE #7457)
  76. GRB990308 not a new SGR
  77. GRB 990308a and GRB 990308b
  78. GRB990308 (Trig. 7457), optical observations
  79. GRB981220, IPN localization
  80. GRB 981220, radio observations
  81. GRB 990123, Field Photometry
  82. GRB 990217 Optical Observations
  83. GRB 990217, radio observations
  84. Optical Observations of GRB990217
  85. GRB990123: Caltech STIS Photometry and Images
  86. GRB990123 observations
  87. GRB990123, Optical Observation
  88. GRB 990123: Discovery of the Probable Host Galaxy
  89. GRB 990123: Reduced HST Images
  90. For Immediate Posting to GCN - HST Data GRB 990123 Available
  91. GRB19990123 observations
  92. GRB 990123: BVRI standards in the field
  93. GRB 990123: Updated Keck Spectroscopy Results
  94. GRB981220, field photometry
  95. GRB 990123 NOT Spectrum Update
  96. GRB990123, Optical observation
  97. GRB990123, is the "radio flare" due to an inhomogeneous medium?
  98. GRB 990123: Publicly available reduced HST images
  99. GRB990123, Upcoming HST Service Observations
  100. GRB 990123: New Constraints on Possible Foreground Galaxies

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