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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"

35934 results found.

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

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