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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').
  1. GRB980703: Radio transient
  2. GRB980703 H-band Observations
  3. GRB 980703: Spectrum of the proposed optical counterpart
  4. RXTE Observation of GRB 980706
  5. GRB980703: Spectrum of the proposed optical counterpart
  6. GRB980703 Transient Optical Follow-Up
  7. GRB980703: LOTIS observation at early times
  8. GRB980613 Optical Observations
  9. GRB 980703
  10. GRB980703 (I band observations)
  11. GRB 980703 H-band Observations
  12. GRB980703 (optical R observations)
  13. GRB980706
  14. GRB980703: radio source/optical transient
  15. BeppoSAX NFI observations of GRB 980703
  16. GRB 980703: ASM Position & Intensity
  17. GRB980703
  18. GRB980519 observation report
  19. GRB980703 optical followup
  20. SGR1627-41
  21. Radio observations of SGRs
  22. SGR1900+14 field optical observations
  23. GRB 980613 Near-IR observations
  24. GRB980613, optical observations
  25. GRB 980613: Optical transient and its host galaxy
  26. SGR1627-41, RXTE/ASM observations
  27. SGR1627-41, Refined IPN annulus location
  28. GRB 980613: Detection of the probable host galaxy
  29. Reduced error box of SGR 1627-41
  30. GRB 980613: BATSE Observations
  31. SGR1627-41, BeppoSAX-GRBM detections
  32. SGR 1627-41
  33. GRB 980613 Optical Observations
  34. GRB 980613 optical observations
  35. Discovery of a new SGR source, SGR1627-41
  36. GRB980613 Optical Observations
  37. GRB980613 observations from Palomar
  38. GRB980613 BeppoSAX-NFI follow up
  39. GRB 980613 new optical/IR observations
  40. GRB 980613 optical/IR obs.
  41. GRB980613 Near Infra-Red Observations
  42. GRB980611
  43. GRB980613, BeppoSAX WFC positions
  44. GRB971214 Secondary Standards
  45. SGR 1900+14
  46. GRB980519 Secondary Standards
  47. SGR1900+14
  48. SGR1900+14
  49. BATSE on-board GRB trigger change
  50. GRB 980519 Optical Observations
  51. GRB980519 optical observations
  52. GRB980519 I-band observations
  53. GRB 980519
  54. GRB980519 optical observations
  55. GRB 980519 Optical Observations
  56. GRB980519 BATSE Observations
  57. GRB970519, optical follow-up at Schmidt Calern
  58. GRB980519 optical observations
  59. GRB980519 Optical Observations
  60. GRB980519 Optical Observations
  61. GRB980519 IPN POSITION
  62. GRB980519 Optical Observations
  63. GRB 980519 Optical Observations
  64. GRB980519 optical observations
  65. GRB980515, BeppoSAX IAUC to be submitted
  66. BATSE on-board GRB trigger change
  67. GRB980519, BeppoSAX-WFC updated position
  68. GRB980519, BeppoSAX-WFC position
  69. GRB980515: SAX-WFC updated position
  70. BeppoSAX GRB ALERT: updated position of grb980515
  71. GRB 980425 Radio Light Curve
  72. GRB 980425 Brightness Temperature
  73. BSAX Observations of GRB980425 field
  74. IPN web site of GRBs
  75. GRB980425 BATSE observations
  76. SAX J0840.7+2248 Optical Observations
  77. GRB 980425 optical observations
  78. GRB980425: optical obs.
  79. GRB980425: Radio Observations
  80. GRB 980425 optical observations
  81. report on BSAX observations of GRB980425
  82. GRB 980425 optical observations
  83. GRB 980329 ROSAT observation
  84. GRB980326 X-ray Observations
  85. GRB980326, optical observations
  86. GRB980326, optical observations
  87. GRB980329, Fading IR counterpart to radio source
  88. GRByymmdd, Announcement of automation
  89. GRB980326 IPN annulus
  90. GRB980329
  91. GRB980329 Keck K-band observations
  92. GRB980329 sub-millimeter observations
  93. GRB980329 IPN annulus
  94. GRB980329 optical observations
  95. GRB980329 near-IR observations
  96. GRB980329 near-IR observations
  97. GRB980329 optical observations
  98. GRB980329 infrared observations
  99. GRB980329 optical observations
  100. GRB980326 optical observations

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