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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"

42559 results found.

  1. GRB 030329 VLBA Observations
  2. IPN triangulation of GRB030406 (small error box)
  3. IPN triangulation of GRB050403 (small error box)
  4. IPN triangulation of GRB030403 (annulus)
  5. GRB 030329: BVRI photometry at Asiago
  6. GRB 030329, light curve flattens
  7. GRB 030329: VLT V-band photometry
  8. If the SN/GRB connection confirmed
  9. GRB 030329: Supernova Confirmed
  10. GRB030329: RTT150 optical observations
  11. GRB030329: HET spectroscopic monitoring
  12. GRB 030329, color evolution
  13. GRB030328, UBVRcIc field photometry
  14. GRB030329: Optical observcations
  15. GRB030329: BV photographic observations
  16. GRB 030329, color evolution
  17. GRB030329: RTT150 optical observations
  18. GRB 030329: Supernova Spectrum Emerging
  19. GRB030329: RTT150 optical observation
  20. GRB030329: More AAVSO VR obs
  21. GRB030328: R upper limit after 6 hours by MASTER
  22. GRB 030329: SARA Optical Observations
  23. GRB 030329: SARA Optical Observations
  24. GRB030329, fading resumes
  25. GRB 030329, BVRI photometry
  26. GRB030329: Optical observations
  27. SDSS 0.5m PT observations of GRB030329 (correction)
  28. SDSS 0.5m PT observations of GRB030329
  29. GRB 030329, Optical observations
  30. GRB 030329, nearby galaxies
  31. GRB030329, cessation of fading
  32. GRB030329: final R-band light curve by MASTER
  33. GRB 030329: Sub-millimeter detection
  34. GRB 030329: SARA Optical Observations
  35. GRB 030329: SARA Optical Observations
  36. OT GRB light curves and SN predictions
  37. GRB030329, optical observation
  38. GRB030329, optical observation
  39. GRB030329, new UBVRcIc field photometry
  40. GRB 030329, light curve and SN prediction
  41. GRB030329: optical observations at Tokyo Tech
  42. GRB 030329: optical observations
  43. GRB030329: multiple re-brightening phases
  44. GRB 030329, BRI photometry
  45. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  46. GRB 030329 , SPM optical observations
  47. GRB 030329: Radio observations at GMRT
  48. Further AAVSO V,B,R observations of GRB030329
  49. GRB 030329: Additional Mt. Laguna Optical Observations
  50. GRB 030329: SARA Optical Observations
  51. GRB 030329: Observations with ANDICAM
  52. GRB030329: Optical observations
  53. GRB030329: further optical photometry and evidence for a light curve discontinuity
  54. GRB 030329: Correction to GCN 2056
  55. GRB 030329: fitting parameters and re-brightening
  56. GRB030329 Further RBO Optical Observations
  57. triangulation of GRB 030331 (single error box)
  58. GRB030329 - OT rebrightens
  59. GRB 030329: SARA Optical Observations
  60. AAVSO V & R observations of GRB030329
  61. IPN triangulation of GRB030331 (annulus)
  62. GRB 030329: optical observations
  63. IPN triangulation of GRB030329b (large error box)
  64. GRB 030329: beginning of the new fading phase in optical band
  65. GRB 030329, optical spectroscopy
  66. GRB 030329: fading X-ray afterglow with RXTE
  67. GRB 030329: optical photometry
  68. GRB030329: Optical observations
  69. Photometry of GRB030329 - Constant OT Magnitude
  70. GRB 030329, R-band observations
  71. GRB 030329, R-band light curve
  72. GRB 030329: further optical observations
  73. GRB030329 - OT brightens
  74. GRB030329 15 GHz radio observation
  75. GRB 030329, optical photometry
  76. GRB030329: Near Infrared Observations
  77. 030331 NOT A GRB
  78. GRB 030324: Optical and NIR Observations
  79. GRB 030328, optical photometry
  80. GRB030329: R band light curve by MASTER
  81. GRB030329 - Light curve flattening
  82. GRB 030329: SARA Optical Observations
  83. GRB 030324, optical search
  84. GRB030329 - near contemporaneous optical limits from CONCAM
  85. GRB030329: R and B observations
  86. GRB030329: Optical observations
  87. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  88. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  89. GRB 030329: Light curve observed during the change of its slope.
  90. GRB030329, BVRcIc field photometry
  91. GRB030329, SPM optical observations
  92. GRB 030329: Optical Decay
  93. Redshift of GRB 030329
  94. GRB030329: ROTSE network observes steepening of decay curve
  95. GRB 030329, optical photometry
  96. GRB 030329: Optical decay and synthesis
  97. GRB030329 optical observations
  98. GRB030329: optical spectroscopy with the TNG
  99. GRB 030329: Radio Observations
  100. GRB 030329, optical spectroscopy

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