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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"

16155 results found.

  1. GRB990123, Preliminary Lens Search Results
  2. On the Lensing Interpretation of GRB 990123
  3. Search for Potential Images of GRB 990123
  4. Search for Potential Images of GRB 990123
  5. GRB990123, Optical BVRI Observations
  6. GRB 990123: near-infrared observations.
  7. GRB990123: NIR Observation
  8. "GRB 990123: New BV Observations"
  9. GRB 990123 Optical Follow-Up
  10. GRB 990123: BATSE Observations
  11. GRB990123 IPN annulus
  12. GRB990123 Optical Observations
  13. GRB 990123 Spectroscopic Redshifts
  14. GRB 990123: New Optical Observations, Decay Measure
  15. GRB 990123 Optical Follow-Up
  16. GRB 990123: Possible Gravitationally Lensed Burst?
  17. GRB990123, optical observation
  18. GRB 990123 optical observations
  19. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  20. GRB 990123 radio observations
  21. GRB 990123, new radio source
  22. GRB990123 optical observations
  23. GRB990123, Optical observation
  24. GRB 990123: Optical Decay Slope
  25. GRB 990123 r-band photometry
  26. GRB 990123 Optical Follow-up
  27. GRB990123, early optical counterpart detection
  28. GRB990123 Optical Observation
  29. GRB 990123: Bright New Source, Possible Optical Transient
  30. Optical Observations of GRB 981220
  31. GRB 981226: radio variable
  32. GRB981220, Correction to GCN 179
  33. GRB981220, Optical Observations
  34. GRB 981220 Optical observations
  35. GRB 981226 Optical Observations
  36. GRB 981220 and GRB 981226, optical observations
  37. GRB981226 Optical Observations
  38. GRB 981226 radio observations
  39. GRB 981226
  40. GRB 981226 optical observations
  41. radio observations of GRB 981226
  42. GRB981220 B, R and I band observations
  43. Optical Observations of GRB981226
  44. GRB 981220:Optical Observations
  45. GRB 981220 optical R and I observations
  46. GRB 981226 optical observations
  47. GRB 981220, radio observations
  48. GRB981226 Optical Observation
  49. GRB981220 Optical Observations
  50. GRB 981220 Optical Observations
  51. GRB 981220, optical observations
  52. GRB 980326/Host Galaxy
  53. GRB980329 R,I flux calibration and R,I,K upper limits
  54. GRB980425 Optical Follow-up
  55. GRB970508 optical observations
  56. GRB971214, association with a Galactic star?
  57. Optical Observations of the Host Galaxy of GRB 980519
  58. GRB980519, Optical Observations
  59. GRB980703 optical photometry
  60. GRB980703 optical observations
  61. GRB980703 H-band Observations
  62. GRB 980703: Spectrum of the proposed optical counterpart
  63. GRB980703: Spectrum of the proposed optical counterpart
  64. GRB980703 Transient Optical Follow-Up
  65. GRB980613 Optical Observations
  66. GRB980703 (I band observations)
  67. GRB 980703 H-band Observations
  68. GRB980703 (optical R observations)
  69. GRB980703: radio source/optical transient
  70. GRB980519 observation report
  71. GRB980703 optical followup
  72. SGR1900+14 field optical observations
  73. GRB 980613 Near-IR observations
  74. GRB980613, optical observations
  75. GRB 980613: Optical transient and its host galaxy
  76. GRB 980613: Detection of the probable host galaxy
  77. GRB 980613 Optical Observations
  78. GRB 980613 optical observations
  79. GRB980613 Optical Observations
  80. GRB980613 observations from Palomar
  81. GRB 980613 new optical/IR observations
  82. GRB 980613 optical/IR obs.
  83. GRB980613 Near Infra-Red Observations
  84. GRB971214 Secondary Standards
  85. GRB980519 Secondary Standards
  86. SGR1900+14
  87. SGR1900+14
  88. GRB 980519 Optical Observations
  89. GRB980519 optical observations
  90. GRB980519 I-band observations
  91. GRB 980519
  92. GRB980519 optical observations
  93. GRB 980519 Optical Observations
  94. GRB970519, optical follow-up at Schmidt Calern
  95. GRB980519 optical observations
  96. GRB980519 Optical Observations
  97. GRB980519 Optical Observations
  98. GRB980519 IPN POSITION
  99. GRB980519 Optical Observations
  100. GRB 980519 Optical Observations

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