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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"

32714 results found.

  1. GRB030329: RTT150 optical observations
  2. GRB030329: Near Infrared Observations at Gunma
  3. GRB030329: HET spectroscopic monitoring
  4. Kiso observation of the GRB030329 at April 6
  5. GRB 030329, color evolution
  6. GRB030328, UBVRcIc field photometry
  7. GRB 030329 Optical observations
  8. GRB 030329, color evolution
  9. GRB 030329: possible color change
  10. GRB030329: RTT150 optical observations
  11. GRB 030329: Supernova Spectrum Emerging
  12. GRB030329: Kiso B and R band observations
  13. GRB030329: RTT150 optical observation
  14. GRB030329: More AAVSO VR obs
  15. GRB030328: R upper limit after 6 hours by MASTER
  16. GRB 030329: BV photographic observations
  17. GRB 030329: SARA Optical Observations
  18. GRB 030329: SARA Optical Observations
  19. GRB030329, fading resumes
  20. GRB 030329, BVRI photometry
  21. SDSS 0.5m PT observations of GRB030329 (correction)
  22. SDSS 0.5m PT observations of GRB030329
  23. GRB 030329, Optical observations
  24. GRB 030329, nearby galaxies
  25. GRB030329, cessation of fading
  26. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  27. GRB 030329: Sub-millimeter detection
  28. GRB 030329: SARA Optical Observations
  29. GRB 030329: SARA Optical Observations
  30. OT GRB light curves and SN predictions
  31. GRB030329, optical observation
  32. GRB030329, new UBVRcIc field photometry
  33. GRB 030329, light curve and SN prediction
  34. GRB030329: optical observations at Tokyo Tech
  35. GRB 030329: optical observations
  36. GRB030329: multiple re-brightening phases
  37. GRB 030329, BRI photometry
  38. GRB 030329 , SPM optical observations
  39. GRB 030329: Radio observations at GMRT
  40. Further AAVSO V,B,R observations of GRB030329
  41. GRB 030329: Additional Mt. Laguna Optical Observations
  42. GRB 030329: SARA Optical Observations
  43. GRB 030329: Observations with ANDICAM
  44. GRB030329: further optical photometry and evidence for a light curve discontinuity
  45. GRB 030329: Correction to GCN 2056
  46. GRB 030329: fitting parameters and re-brightening
  47. GRB 030329: KAIT optical photometry
  48. GRB030329 Further RBO Optical Observations
  49. triangulation of GRB 030331 (single error box)
  50. GRB030329 - OT rebrightens
  51. GRB 030329: SARA Optical Observations
  52. AAVSO V & R observations of GRB030329
  53. IPN triangulation of GRB030331 (annulus)
  54. GRB 030329: optical observations
  55. IPN triangulation of GRB030329b (large error box)
  56. GRB 030329: beginning of the new fading phase in optical band
  57. GRB 030329, optical spectroscopy
  58. GRB 030329: fading X-ray afterglow with RXTE
  59. GRB 030329: optical photometry
  60. Photometry of GRB030329 - Constant OT Magnitude
  61. GRB 030329, R-band observations
  62. GRB 030329, R-band light curve
  63. GRB 030329: further optical observations
  64. GRB030329 - OT brightens
  65. GRB 030329: OT observations at Kanazawa
  66. GRB030329 15 GHz radio observation
  67. GRB 030329 RBO V Optical Observations
  68. GRB 030329, optical photometry
  69. GRB030329: Near Infrared Observations
  70. 030331 NOT A GRB
  71. INTEGRAL GRB 030331
  72. GRB 030324: Optical and NIR Observations
  73. GRB 030328, optical photometry
  74. GRB030329: R band light curve by MASTER
  75. GRB030329 - Light curve flattening
  76. GRB 030329: SARA Optical Observations
  77. GRB 030324, optical search
  78. GRB030329 - near contemporaneous optical limits from CONCAM
  79. GRB 030329, optical observations
  80. GRB 030329: Light curve observed during the change of its slope.
  81. GRB030329, BVRcIc field photometry
  82. GRB030329, SPM optical observations
  83. GRB 030329: Optical Decay
  84. Redshift of GRB 030329
  85. GRB030329: ROTSE network observes steepening of decay curve
  86. GRB 030329, optical photometry
  87. GRB 030329: Optical decay and synthesis
  88. GRB 030329: Radio Observations
  89. GRB 030329, optical spectroscopy
  90. GRB 030329: still bright
  91. GRB 030329: Optical pre-Imaging
  92. GRB 030329: visual observations
  93. GRB 030329: Upper limit from 5.6 hours before trigger
  94. GRB030328: R optical observation
  95. GRB 030323: Gemini South VRI obsevations.
  96. GRB030329: Optical observations
  97. GRB 030329, R-band observations, supplement
  98. GRB030329:optical observations by MASTER
  99. GRB 030329: optical observations
  100. GRB 030329, R-band observations

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