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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"

28697 results found.

  1. GRB980703 Very Long Baseline Interferometry
  2. GRB970508 optical observations
  3. Optical Observations of the Host Galaxy of GRB 980519
  4. GRB980519, Optical Observations
  5. GRB980703, Host galaxy multicolor photometry
  6. GRB 980703 (NFI observations)
  7. GRB980703 optical photometry
  8. GRB 980703: BATSE Observations
  9. GRB980703 optical observations
  10. GRB980703: Radio transient
  11. GRB980703 H-band Observations
  12. GRB 980703: Spectrum of the proposed optical counterpart
  13. RXTE Observation of GRB 980706
  14. GRB980703: Spectrum of the proposed optical counterpart
  15. GRB980703 Transient Optical Follow-Up
  16. GRB980703: LOTIS observation at early times
  17. GRB980613 Optical Observations
  18. GRB 980703
  19. GRB980703 (I band observations)
  20. GRB 980703 H-band Observations
  21. GRB980703: radio source/optical transient
  22. BeppoSAX NFI observations of GRB 980703
  23. GRB980519 observation report
  24. Radio observations of SGRs
  25. GRB 980613 Near-IR observations
  26. GRB980613, optical observations
  27. GRB 980613: Optical transient and its host galaxy
  28. SGR1627-41, RXTE/ASM observations
  29. SGR1627-41, Refined IPN annulus location
  30. GRB 980613: Detection of the probable host galaxy
  31. Reduced error box of SGR 1627-41
  32. SGR1627-41, BeppoSAX-GRBM detections
  33. GRB 980613 Optical Observations
  34. GRB 980613 optical observations
  35. GRB980613 Optical Observations
  36. GRB980613 observations from Palomar
  37. GRB 980613 new optical/IR observations
  38. GRB971214 Secondary Standards
  39. GRB980519 Secondary Standards
  40. SGR1900+14
  41. GRB 980519 Optical Observations
  42. GRB980519 optical observations
  43. GRB980519 I-band observations
  44. GRB 980519
  45. GRB980519 optical observations
  46. GRB 980519 Optical Observations
  47. GRB980519 BATSE Observations
  48. GRB970519, optical follow-up at Schmidt Calern
  49. GRB980519 optical observations
  50. GRB980519 Optical Observations
  51. GRB980519 Optical Observations
  52. GRB980519 IPN POSITION
  53. GRB980519 Optical Observations
  54. GRB 980519 Optical Observations
  55. GRB980519 optical observations
  56. GRB980515, BeppoSAX IAUC to be submitted
  57. GRB980519, BeppoSAX-WFC updated position
  58. GRB 980425 Radio Light Curve
  59. GRB 980425 Brightness Temperature
  60. BSAX Observations of GRB980425 field
  61. IPN web site of GRBs
  62. GRB980425 BATSE observations
  63. SAX J0840.7+2248 Optical Observations
  64. GRB 980425 optical observations
  65. GRB980425: optical obs.
  66. GRB980425: Radio Observations
  67. GRB 980425 optical observations
  68. GRB980326, optical observations
  69. GRB980326, optical observations
  70. GRB980329, Fading IR counterpart to radio source
  71. GRByymmdd, Announcement of automation
  72. GRB980326 IPN annulus
  73. GRB980329
  74. GRB980329 Keck K-band observations
  75. GRB980329 sub-millimeter observations
  76. GRB980329 IPN annulus
  77. GRB980329 optical observations
  78. GRB980329 near-IR observations
  79. GRB980329 optical observations
  80. GRB980326 optical observations
  81. GRB980326 optical observations
  82. GRB970508 SAO RAS optical observations
  83. GRB 971214: Redshift from Keck Observations
  84. Near-IR follow-up on GRB 971227
  85. GRB971214: Keck R & I-band Observations
  86. GRB 971227: Optical Observations
  87. Optical Observations of the GRB 971227 field
  88. GRB971227: Plaskett R-band observations
  89. GRB 971227: Optical clarifications
  90. GRB971227: LOTIS observations
  91. GRB971214: Optical Observations and Calibrations
  92. Optical Observations of GRB 971214 at Keck
  93. GRB 971024: Refined analysis by USNOFS Observations
  94. GRB 971024: USNO Observations
  95. GRB 970925: BATSE Localization
  96. IRAS 18119-1342 and the possible new SGR
  97. GRB 970228: Keck/LRIS Optical Observations

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