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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"

32796 results found.

  1. GRB030328: R upper limit after 6 hours by MASTER
  2. GRB 030329: BV photographic observations
  3. GRB 030329: SARA Optical Observations
  4. GRB 030329: SARA Optical Observations
  5. GRB030329, fading resumes
  6. GRB 030329, BVRI photometry
  7. SDSS 0.5m PT observations of GRB030329 (correction)
  8. SDSS 0.5m PT observations of GRB030329
  9. GRB 030329, Optical observations
  10. GRB 030329, nearby galaxies
  11. GRB030329, cessation of fading
  12. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  13. GRB 030329: Sub-millimeter detection
  14. GRB 030329: SARA Optical Observations
  15. GRB 030329: SARA Optical Observations
  16. OT GRB light curves and SN predictions
  17. GRB030329, optical observation
  18. GRB030329, new UBVRcIc field photometry
  19. GRB 030329, light curve and SN prediction
  20. GRB030329: optical observations at Tokyo Tech
  21. GRB 030329: optical observations
  22. GRB030329: multiple re-brightening phases
  23. GRB 030329, BRI photometry
  24. GRB 030329 , SPM optical observations
  25. GRB 030329: Radio observations at GMRT
  26. Further AAVSO V,B,R observations of GRB030329
  27. GRB 030329: Additional Mt. Laguna Optical Observations
  28. GRB 030329: SARA Optical Observations
  29. GRB 030329: Observations with ANDICAM
  30. GRB030329: further optical photometry and evidence for a light curve discontinuity
  31. GRB 030329: Correction to GCN 2056
  32. GRB 030329: fitting parameters and re-brightening
  33. GRB 030329: KAIT optical photometry
  34. GRB030329 Further RBO Optical Observations
  35. triangulation of GRB 030331 (single error box)
  36. GRB030329 - OT rebrightens
  37. GRB 030329: SARA Optical Observations
  38. AAVSO V & R observations of GRB030329
  39. IPN triangulation of GRB030331 (annulus)
  40. GRB 030329: optical observations
  41. IPN triangulation of GRB030329b (large error box)
  42. GRB 030329: beginning of the new fading phase in optical band
  43. GRB 030329, optical spectroscopy
  44. GRB 030329: fading X-ray afterglow with RXTE
  45. GRB 030329: optical photometry
  46. Photometry of GRB030329 - Constant OT Magnitude
  47. GRB 030329, R-band observations
  48. GRB 030329, R-band light curve
  49. GRB 030329: further optical observations
  50. GRB030329 - OT brightens
  51. GRB 030329: OT observations at Kanazawa
  52. GRB030329 15 GHz radio observation
  53. GRB 030329 RBO V Optical Observations
  54. GRB 030329, optical photometry
  55. GRB030329: Near Infrared Observations
  56. 030331 NOT A GRB
  57. INTEGRAL GRB 030331
  58. GRB 030324: Optical and NIR Observations
  59. GRB 030328, optical photometry
  60. GRB030329: R band light curve by MASTER
  61. GRB030329 - Light curve flattening
  62. GRB 030329: SARA Optical Observations
  63. GRB 030324, optical search
  64. GRB030329 - near contemporaneous optical limits from CONCAM
  65. GRB 030329, optical observations
  66. GRB 030329: Light curve observed during the change of its slope.
  67. GRB030329, BVRcIc field photometry
  68. GRB030329, SPM optical observations
  69. GRB 030329: Optical Decay
  70. Redshift of GRB 030329
  71. GRB030329: ROTSE network observes steepening of decay curve
  72. GRB 030329, optical photometry
  73. GRB 030329: Optical decay and synthesis
  74. GRB 030329: Radio Observations
  75. GRB 030329, optical spectroscopy
  76. GRB 030329: still bright
  77. GRB 030329: Optical pre-Imaging
  78. GRB 030329: visual observations
  79. GRB 030329: Upper limit from 5.6 hours before trigger
  80. GRB030328: R optical observation
  81. GRB 030323: Gemini South VRI obsevations.
  82. GRB030329: Optical observations
  83. GRB 030329, R-band observations, supplement
  84. GRB030329:optical observations by MASTER
  85. GRB 030329: optical observations
  86. GRB 030329, R-band observations
  87. GRB 030329: OT B and R photometry, decline rate
  88. GRB030329: Upper limits from recent and historical observations.
  89. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  90. RXTE detection of GRB 030329 afterglow
  91. GRB 030329: Optical Afterglow Observations
  92. GRB 030329: precise position from Kyoto images
  93. GRB 030328 Optical Observations
  94. GRB 030328: Optical observations
  95. GRB 030328: optical observations
  96. GRB 030329: Optical afterglow fading
  97. GRB 030329 follow-up
  98. GRB 030329: Optical afterglow candidate
  99. GRB 030329: OT candidate
  100. GRB 030329: Optical afterglow candidate

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