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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"

21575 results found.

  1. "GRB 990123: New BV Observations"
  2. GRB 990123 Optical Follow-Up
  3. GRB 990123; Addendum to GCN 223
  4. GRB 990123: BATSE Observations
  5. GRB990123 Optical Observations
  6. GRB 990123 Spectroscopic Redshifts
  7. GRB 990123: New Optical Observations, Decay Measure
  8. GRB 990123: Possible Gravitationally Lensed Burst?
  9. GRB 990123 optical observations
  10. GRB 990123: Pre-Burst Detection of an Apparent Host Galaxy
  11. GRB 990123 radio observations
  12. GRB 990123, new radio source
  13. GRB990123 optical observations
  14. GRB 990123 Optical Follow-up
  15. GRB990123, early optical counterpart detection
  16. GRB 990123, Radio observations
  17. SN 1999E & GRB 980919
  18. Possible identification of SN1999E with GRB980910
  19. Optical Observations of GRB 981220
  20. GRB981220
  21. GRB981220, Correction to GCN 179
  22. GRB981220, Optical Observations
  23. GRB 981220 Optical observations
  24. GRB 981226 Optical Observations
  25. GRB 980613: Spectroscopy of the host galaxy
  26. GRB981226, sub-millimeter observations
  27. GRB981220, sub-millimeter observations
  28. GRB 981220 and GRB 981226, optical observations
  29. GRB981226 Optical Observations
  30. GRB 981226 radio observations
  31. GRB 981226
  32. GRB 981226 optical observations
  33. radio observations of GRB 981226
  34. GRB981220 B, R and I band observations
  35. Optical Observations of GRB981226
  36. GRB 981220:Optical Observations
  37. GRB 981220 optical R and I observations
  38. GRB981226, BeppoSAX Christmas GRB
  39. GRB 981226 - Infrared Observations
  40. GRB 981226 optical observations
  41. GRB 981220
  42. GRB 981220, radio observations
  43. GRB981226 Optical Observation
  44. GRB 981220, radio observations
  45. GRB981220 I-band Observations
  46. GRB981220 Optical Observations
  47. GRB 981220
  48. GRB 981220 Optical Observations
  49. GRB 981220, optical observations
  50. GRB 980326/Host Galaxy
  51. GRB980329 R,I flux calibration and R,I,K upper limits
  52. GRB980425 Optical Follow-up
  53. GRB980425: X-ray revised positions
  54. GRB 980923 BATSE Observations
  55. SGR1900+14, BeppoSAX-GRBM observations
  56. GRB980703 Very Long Baseline Interferometry
  57. GRB970508 optical observations
  58. Optical Observations of the Host Galaxy of GRB 980519
  59. GRB980519, Optical Observations
  60. GRB 980703 (NFI observations)
  61. GRB980703 optical photometry
  62. GRB 980703: BATSE Observations
  63. GRB980703 optical observations
  64. GRB980703 H-band Observations
  65. GRB 980703: Spectrum of the proposed optical counterpart
  66. GRB980703: Spectrum of the proposed optical counterpart
  67. GRB980613 Optical Observations
  68. GRB980703 (I band observations)
  69. GRB 980703 H-band Observations
  70. GRB980703 (optical R observations)
  71. GRB980703: radio source/optical transient
  72. BeppoSAX NFI observations of GRB 980703
  73. GRB980703 optical followup
  74. Radio observations of SGRs
  75. SGR1900+14 field optical observations
  76. GRB 980613 Near-IR observations
  77. GRB980613, optical observations
  78. SGR1627-41, RXTE/ASM observations
  79. GRB 980613: Detection of the probable host galaxy
  80. Reduced error box of SGR 1627-41
  81. GRB 980613: BATSE Observations
  82. GRB 980613 Optical Observations
  83. GRB 980613 optical observations
  84. Discovery of a new SGR source, SGR1627-41
  85. GRB980613 Optical Observations
  86. GRB980613 observations from Palomar
  87. GRB 980613 new optical/IR observations
  88. GRB 980613 optical/IR obs.
  89. GRB980613 Near Infra-Red Observations
  90. GRB971214 Secondary Standards
  91. SGR 1900+14
  92. GRB980519 Secondary Standards
  93. SGR1900+14
  94. SGR1900+14
  95. GRB 980519 Optical Observations
  96. GRB980519 optical observations
  97. GRB980519 I-band observations
  98. GRB 980519
  99. GRB980519 optical observations
  100. GRB 980519 Optical Observations

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