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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. GRB971214 Secondary Standards
  2. SGR 1900+14
  3. GRB980519 Secondary Standards
  4. SGR1900+14
  5. SGR1900+14
  6. BATSE on-board GRB trigger change
  7. GRB 980519 Optical Observations
  8. GRB980519 optical observations
  9. GRB980519 I-band observations
  10. GRB 980519
  11. GRB980519 optical observations
  12. GRB 980519 Optical Observations
  13. GRB980519 BATSE Observations
  14. GRB970519, optical follow-up at Schmidt Calern
  15. GRB980519 optical observations
  16. GRB980519 Optical Observations
  17. GRB980519 Optical Observations
  18. GRB980519 IPN POSITION
  19. GRB980519 Optical Observations
  20. GRB 980519 Optical Observations
  21. GRB980519 optical observations
  22. GRB980515, BeppoSAX IAUC to be submitted
  23. BATSE on-board GRB trigger change
  24. GRB980519, BeppoSAX-WFC updated position
  25. GRB980519, BeppoSAX-WFC position
  26. GRB980515: SAX-WFC updated position
  27. BeppoSAX GRB ALERT: updated position of grb980515
  28. GRB 980425 Radio Light Curve
  29. GRB 980425 Brightness Temperature
  30. BSAX Observations of GRB980425 field
  31. IPN web site of GRBs
  32. GRB980425 BATSE observations
  33. SAX J0840.7+2248 Optical Observations
  34. GRB 980425 optical observations
  35. GRB980425: optical obs.
  36. GRB980425: Radio Observations
  37. GRB 980425 optical observations
  38. report on BSAX observations of GRB980425
  39. GRB 980425 optical observations
  40. GRB 980329 ROSAT observation
  41. GRB980326 X-ray Observations
  42. GRB980326, optical observations
  43. GRB980326, optical observations
  44. GRB980329, Fading IR counterpart to radio source
  45. GRByymmdd, Announcement of automation
  46. GRB980326 IPN annulus
  47. GRB980329
  48. GRB980329 Keck K-band observations
  49. GRB980329 sub-millimeter observations
  50. GRB980329 IPN annulus
  51. GRB980329 optical observations
  52. GRB980329 near-IR observations
  53. GRB980329 near-IR observations
  54. GRB980329 optical observations
  55. GRB980329 infrared observations
  56. GRB980329 optical observations
  57. GRB980326 optical observations
  58. GRB980329 optical observations
  59. GRB980329 VLA observations
  60. GRB980329 near IR observations
  61. GRB980329 optical observations
  62. GRB980329 optical observations
  63. GRB980329 optical observations
  64. GRB980326 optical observations
  65. GRB980326 optical observations
  66. GRB980326 optical observations
  67. GRB980326 optical observations
  68. GRB970508 SAO RAS optical observations
  69. Optical Observations of GRB 970508
  70. GRB 971214: Redshift from Keck Observations
  71. Near-IR follow-up on GRB 971227
  72. GRB971214: Keck R & I-band Observations
  73. GRB 971227: Optical Observations
  74. Optical Observations of the GRB 971227 field
  75. Optical Observations on GRB 971227
  76. GRB971227: Plaskett R-band observations
  77. GRB 971227: Optical clarifications
  78. Optical Observations for GRB 971227
  79. GRB971227: Further CAHA R-band images
  80. GRB971227: LOTIS observations
  81. GRB 971227: CAHA R-band images
  82. GRB 971227: Optical observations
  83. GRB971214: Optical Observations and Calibrations
  84. Sub-millimeter Observations of GRB 971214 at the JCMT
  85. GRB 971214: EUVE Observations
  86. GRB 971214: Redshift from Keck Optical Observations
  87. GRB 971214: Redshift from Keck Optical Observations
  88. GRB 971214: Apache Point Observatory Optical Observations
  89. GRB 971214: KPNO Optical Observations
  90. Optical Observations of GRB 971214 at Keck
  91. GRB 971214: Optical Observations
  92. Radio Observations of GRB 971214 at the VLA
  93. GRB 971214: USNOFS Observations Summary
  94. GRB 971024: KPNO Optical Observations Summary
  95. GRB 971024: Refined analysis by USNOFS Observations
  96. GRB 971024: KPNO Optical Observations
  97. GRB 971024: USNO Observations
  98. GRB 970925: BATSE Localization
  99. IRAS 18119-1342 and the possible new SGR
  100. Possible new SGR from US Naval Observatory

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