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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"

26301 results found.

  1. GRB980703 optical photometry
  2. GRB 980703: BATSE Observations
  3. GRB980703 optical observations
  4. GRB980703: Radio transient
  5. GRB980703 H-band Observations
  6. GRB 980703: Spectrum of the proposed optical counterpart
  7. GRB980703: Spectrum of the proposed optical counterpart
  8. GRB980703 Transient Optical Follow-Up
  9. GRB980703: LOTIS observation at early times
  10. GRB980613 Optical Observations
  11. GRB980703 (I band observations)
  12. GRB 980703 H-band Observations
  13. GRB980703 (optical R observations)
  14. GRB980703: radio source/optical transient
  15. Radio observations of SGRs
  16. SGR1900+14 field optical observations
  17. GRB 980613 Near-IR observations
  18. GRB980613, optical observations
  19. GRB 980613: Optical transient and its host galaxy
  20. GRB 980613: Detection of the probable host galaxy
  21. GRB 980613: BATSE Observations
  22. SGR1627-41, BeppoSAX-GRBM detections
  23. SGR 1627-41
  24. GRB 980613 optical observations
  25. GRB980613 Optical Observations
  26. GRB980613 observations from Palomar
  27. GRB980613 BeppoSAX-NFI follow up
  28. GRB 980613 new optical/IR observations
  29. GRB 980613 optical/IR obs.
  30. GRB980611
  31. GRB980613, BeppoSAX WFC positions
  32. GRB971214 Secondary Standards
  33. SGR 1900+14
  34. GRB980519 Secondary Standards
  35. SGR1900+14
  36. GRB 980519 Optical Observations
  37. GRB980519 optical observations
  38. GRB980519 I-band observations
  39. GRB 980519
  40. GRB980519 optical observations
  41. GRB980519 BATSE Observations
  42. GRB970519, optical follow-up at Schmidt Calern
  43. GRB980519 optical observations
  44. GRB980519 Optical Observations
  45. GRB980519 Optical Observations
  46. GRB980519 IPN POSITION
  47. GRB980519 Optical Observations
  48. GRB 980519 Optical Observations
  49. GRB980519 optical observations
  50. GRB980515, BeppoSAX IAUC to be submitted
  51. GRB980519, BeppoSAX-WFC updated position
  52. GRB980519, BeppoSAX-WFC position
  53. BeppoSAX GRB ALERT: updated position of grb980515
  54. GRB 980425 Radio Light Curve
  55. GRB980425 BATSE observations
  56. GRB980425: optical obs.
  57. GRB980425: Radio Observations
  58. GRB 980425 optical observations
  59. report on BSAX observations of GRB980425
  60. GRB 980425 optical observations
  61. GRB980326, optical observations
  62. GRB980326, optical observations
  63. GRB980329, Fading IR counterpart to radio source
  64. GRB980326 IPN annulus
  65. GRB980329 Keck K-band observations
  66. GRB980329 sub-millimeter observations
  67. GRB980329 IPN annulus
  68. GRB980329 optical observations
  69. GRB980329 near-IR observations
  70. GRB980329 near-IR observations
  71. GRB980329 infrared observations
  72. GRB980329 optical observations
  73. GRB980326 optical observations
  74. GRB980329 optical observations
  75. GRB980329 optical observations
  76. GRB980329 optical observations
  77. GRB980326 optical observations
  78. GRB970508 SAO RAS optical observations
  79. Optical Observations of GRB 970508
  80. GRB 971214: Redshift from Keck Observations
  81. Near-IR follow-up on GRB 971227
  82. GRB971214: Keck R & I-band Observations
  83. GRB 971227: Optical Observations
  84. Optical Observations of the GRB 971227 field
  85. Optical Observations on GRB 971227
  86. GRB971227: Plaskett R-band observations
  87. GRB 971227: Optical clarifications
  88. GRB971227: Further CAHA R-band images
  89. GRB971227: LOTIS observations
  90. GRB 971227: CAHA R-band images
  91. GRB971214: Optical Observations and Calibrations
  92. GRB 971214: Apache Point Observatory Optical Observations
  93. GRB 971214: KPNO Optical Observations
  94. Optical Observations of GRB 971214 at Keck
  95. GRB 971214: Optical Observations
  96. Radio Observations of GRB 971214 at the VLA
  97. GRB 971024: Refined analysis by USNOFS Observations
  98. GRB 970925: BATSE Localization
  99. IRAS 18119-1342 and the possible new SGR
  100. RXTE Observations of SGR 1814-13

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