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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').
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"

19862 results found.

  1. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  2. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  3. X-ray/GRB 1SAX J0835.9+5118, Optical Observation
  4. radio observations of X-ray/GRB transient field
  5. optical observation of the X-ray/GRB transient SAX J0835.9+5118
  6. Optical report on X-ray/GRB transient
  7. GRB 990510: optical linear polarization
  8. GRB 990510: optical observations
  9. GRB990510, VI observations
  10. GRB 990510: Broad Band Break
  11. GRB 990510: BATSE Observations
  12. GRB 990510 optical observations
  13. IPN localization of GRB990510
  14. GRB 990506 Radio Observations
  15. GRB 990123, optical monitoring
  16. GRB 990506: BATSE Observations
  17. GRB 990506, optical observations
  18. GRB 990506, Optical Observations
  19. GRB 990506 optical observations
  20. GRB 990506, optical observations
  21. GRB 990506, optical observations from +1 to +3 hours
  22. GRB 990506, optical observations
  23. GRB990506 observation plan
  24. IPN localization for GRB990506
  25. GRB 990316 Optical Observations
  26. GRB990316, Optical observations
  27. GRB 990316 optical observations
  28. GRB990316: simultaneous optical observation
  29. ASM/IPN error box for GRB 990308 (BATSE #7457)
  30. GRB990308, Possible new SGR~0209+70
  31. GRB 990123, Field Photometry
  32. GRB 990217 Optical Observations
  33. BATSE Flight Anomaly
  34. GRB990123 observations
  35. GRB990123, Optical Observation
  36. GRB 990123: Discovery of the Probable Host Galaxy
  37. GRB19990123 observations
  38. GRB 990123: BVRI standards in the field
  39. GRB 990123: Updated Keck Spectroscopy Results
  40. GRB981220, field photometry
  41. GRB990123, Optical observation
  42. GRB990123, 15-GHz limits
  43. GRB 990123: New Constraints on Possible Foreground Galaxies
  44. GRB990123 Optical Observations
  45. GRB990123, Probability of gravitational lensing
  46. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  47. GRB990123, Preliminary Lens Search Results
  48. Search for Potential Images of GRB 990123
  49. GRB990123, Optical BVRI Observations
  50. GRB 990123: near-infrared observations.
  51. GRB990123, OSSE observations
  52. GRB990123: NIR Observation
  53. "GRB 990123: New BV Observations"
  54. GRB 990123: BATSE Observations
  55. GRB 990123: New Optical Observations, Decay Measure
  56. GRB 990123 Optical Follow-Up
  57. GRB 990123: Possible Gravitationally Lensed Burst?
  58. GRB990123, optical observation
  59. GRB 990123 optical observations
  60. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  61. GRB990123 optical observations
  62. GRB 990123 r-band photometry
  63. GRB 990123 Optical Follow-up
  64. GRB990123 Optical Observation
  65. Possible identification of SN1999E with GRB980910
  66. Optical Observations of GRB 981220
  67. GRB 981226: radio variable
  68. GRB 981226 Optical Observations
  69. GRB981226 Optical Observations
  70. GRB981226 BeppoSAX follow up
  71. GRB 981226 radio observations
  72. GRB 981226
  73. GRB 981226 optical observations
  74. radio observations of GRB 981226
  75. GRB981220 B, R and I band observations
  76. GRB 981220:Optical Observations
  77. GRB 981226 optical observations
  78. GRB 981220, radio observations
  79. GRB 981220, radio observations
  80. GRB 981220
  81. GRB 980326/Host Galaxy
  82. GRB981220 IPN error box
  83. BeppoSAX NFI Observation of GRB980425
  84. GRB980329 R,I flux calibration and R,I,K upper limits
  85. GRB980425 Optical Follow-up
  86. GRB 980923 BATSE Observations
  87. GRB980703 Very Long Baseline Interferometry
  88. GRB970508 optical observations
  89. GRB971214, association with a Galactic star?
  90. GRB980519, Optical Observations
  91. GRB980703, Host galaxy multicolor photometry
  92. GRB980703 - BeppoSAX/GRBM detection
  93. GRB 980703 (NFI observations)
  94. GRB980703 optical photometry
  95. GRB980703 optical observations
  96. GRB980703 Transient Optical Follow-Up
  97. GRB980703: LOTIS observation at early times
  98. GRB980613 Optical Observations
  99. GRB980703 (optical R observations)
  100. BeppoSAX NFI observations of GRB 980703

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