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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"

35933 results found.

  1. GRB 030418: Optical afterglow candidate
  2. GRB 030329 OT position
  3. OT GRB 030329: early UBVRcIc spectral evolution
  4. GRB030329, UBVRI polarimetry, R-polarization
  5. GRB 030329: SARA Optical Observations
  6. OT GRB 030329: early spectrum
  7. GRB030329: VR Photometry at TNG
  8. GRB030324: Candidate Optical Afterglow (Erratum)
  9. GRB030324: Candidate Optical Afterglow
  10. IPN triangulation of GRB030414 (small error box)
  11. GRB 030413: Optical Observations
  12. GRB 030329 Rc observations
  13. IPN triangulation of GRB030413 (small error box)
  14. IPN triangulation of GRB030410 (annulus)
  15. Superluminal motion in GRB 030329 (Correction)
  16. Superluminal motion in GRB 030329
  17. GRB 030329 and SN 2003dh
  18. GRB030329, optical position
  19. GRB 030329 VLBA Observations
  20. IPN triangulation of GRB030406 (small error box)
  21. IPN triangulation of GRB050403 (small error box)
  22. IPN triangulation of GRB030403 (annulus)
  23. GRB 030329: BVRI photometry at Asiago
  24. GRB 030329, light curve flattens
  25. GRB 030329: VLT V-band photometry
  26. If the SN/GRB connection confirmed
  27. GRB 030329: Supernova Confirmed
  28. GRB030329: RTT150 optical observations
  29. GRB030329: Near Infrared Observations at Gunma
  30. GRB030329: HET spectroscopic monitoring
  31. Kiso observation of the GRB030329 at April 6
  32. GRB 030329, color evolution
  33. GRB030328, UBVRcIc field photometry
  34. GRB 030329 Optical observations
  35. GRB 030329, color evolution
  36. GRB 030329: possible color change
  37. GRB030329: RTT150 optical observations
  38. GRB 030329: Supernova Spectrum Emerging
  39. GRB030329: Kiso B and R band observations
  40. GRB030329: RTT150 optical observation
  41. GRB030329: More AAVSO VR obs
  42. GRB030328: R upper limit after 6 hours by MASTER
  43. GRB 030329: BV photographic observations
  44. GRB 030329: SARA Optical Observations
  45. GRB 030329: SARA Optical Observations
  46. GRB030329, fading resumes
  47. GRB 030329, BVRI photometry
  48. SDSS 0.5m PT observations of GRB030329 (correction)
  49. SDSS 0.5m PT observations of GRB030329
  50. GRB 030329, Optical observations
  51. GRB 030329, nearby galaxies
  52. GRB030329, cessation of fading
  53. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  54. GRB 030329: Sub-millimeter detection
  55. GRB 030329: SARA Optical Observations
  56. GRB 030329: SARA Optical Observations
  57. OT GRB light curves and SN predictions
  58. GRB030329, optical observation
  59. GRB030329, new UBVRcIc field photometry
  60. GRB 030329, light curve and SN prediction
  61. GRB030329: optical observations at Tokyo Tech
  62. GRB 030329: optical observations
  63. GRB030329: multiple re-brightening phases
  64. GRB 030329, BRI photometry
  65. GRB 030329 , SPM optical observations
  66. GRB 030329: Radio observations at GMRT
  67. Further AAVSO V,B,R observations of GRB030329
  68. GRB 030329: Additional Mt. Laguna Optical Observations
  69. GRB 030329: SARA Optical Observations
  70. GRB 030329: Observations with ANDICAM
  71. GRB030329: further optical photometry and evidence for a light curve discontinuity
  72. GRB 030329: Correction to GCN 2056
  73. GRB 030329: fitting parameters and re-brightening
  74. GRB 030329: KAIT optical photometry
  75. GRB030329 Further RBO Optical Observations
  76. triangulation of GRB 030331 (single error box)
  77. GRB030329 - OT rebrightens
  78. GRB 030329: SARA Optical Observations
  79. AAVSO V & R observations of GRB030329
  80. IPN triangulation of GRB030331 (annulus)
  81. GRB 030329: optical observations
  82. IPN triangulation of GRB030329b (large error box)
  83. GRB 030329: beginning of the new fading phase in optical band
  84. GRB 030329, optical spectroscopy
  85. GRB 030329: fading X-ray afterglow with RXTE
  86. GRB 030329: optical photometry
  87. Photometry of GRB030329 - Constant OT Magnitude
  88. GRB 030329, R-band observations
  89. GRB 030329, R-band light curve
  90. GRB 030329: further optical observations
  91. GRB030329 - OT brightens
  92. GRB 030329: OT observations at Kanazawa
  93. GRB030329 15 GHz radio observation
  94. GRB 030329 RBO V Optical Observations
  95. GRB 030329, optical photometry
  96. GRB030329: Near Infrared Observations
  97. 030331 NOT A GRB
  98. INTEGRAL GRB 030331
  99. GRB 030324: Optical and NIR Observations
  100. GRB 030328, optical photometry

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