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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"
  1. GRB 030329: SARA Optical Observations
  2. OT GRB light curves and SN predictions
  3. GRB030329, optical observation
  4. GRB030329, optical observation
  5. GRB030329, new UBVRcIc field photometry
  6. GRB 030329, light curve and SN prediction
  7. GRB030329: optical observations at Tokyo Tech
  8. GRB 030329: optical observations
  9. GRB030329: multiple re-brightening phases
  10. GRB 030329, BRI photometry
  11. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  12. GRB 030329 , SPM optical observations
  13. GRB030329: Optical observations at Teramo
  14. GRB 030329: Radio observations at GMRT
  15. GRB030329: more 15GHz observations
  16. Further AAVSO V,B,R observations of GRB030329
  17. GRB 030329: Additional Mt. Laguna Optical Observations
  18. GRB 030329: SARA Optical Observations
  19. GRB 030329: Observations with ANDICAM
  20. GRB030329: Optical observations
  21. GRB030329: further optical photometry and evidence for a light curve discontinuity
  22. GRB 030329: Correction to GCN 2056
  23. GRB 030329: fitting parameters and re-brightening
  24. GRB 030329: KAIT optical photometry
  25. GRB030329 Further RBO Optical Observations
  26. triangulation of GRB 030331 (single error box)
  27. GRB030329 - OT rebrightens
  28. GRB 030329: SARA Optical Observations
  29. AAVSO V & R observations of GRB030329
  30. IPN triangulation of GRB030331 (annulus)
  31. GRB 030329: optical observations
  32. IPN triangulation of GRB030329b (large error box)
  33. GRB 030329: beginning of the new fading phase in optical band
  34. GRB 030329, optical spectroscopy
  35. GRB 030329: fading X-ray afterglow with RXTE
  36. GRB 030329: optical photometry
  37. GRB030329: Optical observations
  38. Photometry of GRB030329 - Constant OT Magnitude
  39. GRB 030329, R-band observations
  40. GRB 030329, R-band light curve
  41. GRB 030329: further optical observations
  42. GRB030329 - OT brightens
  43. GRB 030329: OT observations at Kanazawa
  44. GRB030329 15 GHz radio observation
  45. GRB 030329 RBO V Optical Observations
  46. GRB 030329, optical photometry
  47. GRB030329: Near Infrared Observations
  48. 030331 NOT A GRB
  49. INTEGRAL GRB 030331
  50. GRB 030324: Optical and NIR Observations
  51. GRB 030328, optical photometry
  52. GRB030329: R band light curve by MASTER
  53. GRB030329 - Light curve flattening
  54. GRB 030329: SARA Optical Observations
  55. GRB 030324, optical search
  56. GRB030329 - near contemporaneous optical limits from CONCAM
  57. GRB030329: R and B observations
  58. GRB 030329, optical observations
  59. GRB030329: Optical observations
  60. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  61. GRB030329a: detection by Konus-Wind
  62. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  63. GRB 030329: Light curve observed during the change of its slope.
  64. GRB030329, BVRcIc field photometry
  65. GRB030329, SPM optical observations
  66. GRB 030329: Optical Decay
  67. Redshift of GRB 030329
  68. GRB030329: ROTSE network observes steepening of decay curve
  69. GRB 030329, optical photometry
  70. GRB 030329: Optical decay and synthesis
  71. GRB030329 optical observations
  72. GRB030329: optical spectroscopy with the TNG
  73. GRB 030329: Radio Observations
  74. GRB 030329, optical spectroscopy
  75. GRB 030329: still bright
  76. GRB 030329: Optical pre-Imaging
  77. GRB 030329: visual observations
  78. GRB 030329: Upper limit from 5.6 hours before trigger
  79. GRB030328: R optical observation
  80. GRB030328: X-ray Afterglow Observed with Chandra
  81. GRB 030323: Gemini South VRI obsevations.
  82. GRB030329: Optical observations
  83. GRB 030329, R-band observations, supplement
  84. GRB030329 optical observations
  85. GRB030329:optical observations by MASTER
  86. GRB 030329: optical observations
  87. GRB 030329, R-band observations
  88. GRB 030329: OT B and R photometry, decline rate
  89. GRB030329: Upper limits from recent and historical observations.
  90. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  91. RXTE detection of GRB 030329 afterglow
  92. GRB 030329: Optical Afterglow Observations
  93. GRB 030329: precise position from Kyoto images
  94. GRB 030328 Optical Observations
  95. GRB030328: Decay index
  96. GRB 030328: Optical observations
  97. GRB 030328: optical observations
  98. GRB 030329: Optical afterglow fading
  99. GRB 030329 follow-up
  100. GRB 030329: Optical afterglow candidate

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