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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"

17213 results found.

  1. GRB 990316 Optical Observations
  2. GRB 990316 optical observations
  3. GRB990316: simultaneous optical observation
  4. GRB990308, Possible new SGR~0209+70
  5. GRB 990123, Field Photometry
  6. GRB 990217 Optical Observations
  7. BATSE Flight Anomaly
  8. GRB990217: BeppoSAX/GRBM data
  9. GRB990123 observations
  10. GRB990123, Optical Observation
  11. GRB 990123: Discovery of the Probable Host Galaxy
  12. GRB19990123 observations
  13. GRB 990123: BVRI standards in the field
  14. GRB981220, field photometry
  15. GRB990123, Optical observation
  16. GRB 990123: Publicly available reduced HST images
  17. GRB990123, Upcoming HST Service Observations
  18. GRB990123, 15-GHz limits
  19. GRB 990123: New Constraints on Possible Foreground Galaxies
  20. GRB990123 Optical Observations
  21. GRB 990123: Detection of the IR Transient, and the Light Curve Fits
  22. GRB 990123: Continued Radio Observations
  23. GRB990123, Preliminary Lens Search Results
  24. Search for Potential Images of GRB 990123
  25. GRB990123, Optical BVRI Observations
  26. GRB 990123: near-infrared observations.
  27. GRB990123, OSSE observations
  28. GRB990123: NIR Observation
  29. "GRB 990123: New BV Observations"
  30. GRB 990123: New Optical Observations, Decay Measure
  31. GRB 990123 Optical Follow-Up
  32. GRB 990123: Possible Gravitationally Lensed Burst?
  33. GRB990123, optical observation
  34. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  35. GRB 990123 r-band photometry
  36. GRB 990123 Optical Follow-up
  37. Optical Observations of GRB 981220
  38. GRB 981226: radio variable
  39. GRB 981226 Optical Observations
  40. GRB981226 BeppoSAX follow up
  41. GRB 981226
  42. GRB 981226 optical observations
  43. GRB 981220:Optical Observations
  44. GRB981226, BeppoSAX Christmas GRB
  45. GRB 981226 optical observations
  46. GRB 981220, radio observations
  47. GRB 981220
  48. GRB 980326/Host Galaxy
  49. BeppoSAX NFI Observation of GRB980425
  50. GRB980329 R,I flux calibration and R,I,K upper limits
  51. GRB980425 Optical Follow-up
  52. GRB970508 optical observations
  53. GRB980519, Optical Observations
  54. GRB 980703 (NFI observations)
  55. GRB980703 optical photometry
  56. GRB980703 optical observations
  57. GRB980703: Radio transient
  58. GRB980703 Transient Optical Follow-Up
  59. GRB980703: LOTIS observation at early times
  60. BeppoSAX NFI observations of GRB 980703
  61. GRB980703 optical followup
  62. SGR1627-41
  63. Radio observations of SGRs
  64. SGR1900+14 field optical observations
  65. GRB 980613 Near-IR observations
  66. GRB 980613: Optical transient and its host galaxy
  67. SGR1627-41, Refined IPN annulus location
  68. GRB 980613: Detection of the probable host galaxy
  69. SGR 1627-41
  70. GRB 980613 Optical Observations
  71. GRB 980613 optical observations
  72. Discovery of a new SGR source, SGR1627-41
  73. GRB980613 Optical Observations
  74. GRB980613 observations from Palomar
  75. GRB980613 Near Infra-Red Observations
  76. GRB971214 Secondary Standards
  77. GRB980519 Secondary Standards
  78. GRB 980519 Optical Observations
  79. GRB 980519
  80. GRB980519 optical observations
  81. GRB 980519 Optical Observations
  82. GRB980519 Optical Observations
  83. GRB 980519 Optical Observations
  84. GRB980515, BeppoSAX IAUC to be submitted
  85. BSAX Observations of GRB980425 field
  86. SAX J0840.7+2248 Optical Observations
  87. GRB980425: optical obs.
  88. GRB980425: Radio Observations
  89. report on BSAX observations of GRB980425
  90. GRB980326 X-ray Observations
  91. GRB980326, optical observations
  92. GRB980326, optical observations
  93. GRB980326 IPN annulus
  94. GRB980329 Keck K-band observations
  95. GRB980326 optical observations
  96. GRB980329 optical observations
  97. GRB980329 VLA observations
  98. GRB980329 optical observations
  99. GRB980326 optical observations
  100. Optical Observations of GRB 970508

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