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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').
  1. GRB030329, optical observation
  2. IPN triangulation of GRB030421 (annulus)
  3. MASTER:optical observations GRB030418
  4. MASTER:optical observations probable GRB030414
  5. GRB030329: 444 AAVSO Measurements
  6. IPN triangulation of GRB030419 (annulus)
  7. MASTER:optical observations GRB030416
  8. ROTSE-III prompt optical detections of GRB 030418
  9. GRB030418: Upper limits from recent and historical observations.
  10. GRB030418: Kiso near infrared observations
  11. GRB 030418: Optical afterglow
  12. GRB 030418: Finder for afterglow candidate
  13. GRB 030418: Optical afterglow candidate
  14. GRB 030329 OT position
  15. GRB030329: Optical Observations
  16. OT GRB 030329: early UBVRcIc spectral evolution
  17. GRB030329, UBVRI polarimetry, R-polarization
  18. GRB 030329: SARA Optical Observations
  19. OT GRB 030329: early spectrum
  20. GRB030329: VR Photometry at TNG
  21. GRB030324: Candidate Optical Afterglow (Erratum)
  22. GRB030324: Candidate Optical Afterglow
  23. IPN triangulation of GRB030414 (small error box)
  24. GRB 030413: Optical Observations
  25. GRB 030329 Rc observations
  26. IPN triangulation of GRB030413 (small error box)
  27. IPN triangulation of GRB030410 (annulus)
  28. Superluminal motion in GRB 030329 (Correction)
  29. Superluminal motion in GRB 030329
  30. GRB 030329 and SN 2003dh
  31. GRB030329, optical position
  32. GRB 030329 VLBA Observations
  33. CORRECTION TO IPN TRIANGULATION OF GRB050403
  34. IPN triangulation of GRB030406 (small error box)
  35. IPN triangulation of GRB050403 (small error box)
  36. IPN triangulation of GRB030403 (annulus)
  37. GRB 030329: BVRI photometry at Asiago
  38. GRB 030329, light curve flattens
  39. GRB 030329: VLT V-band photometry
  40. If the SN/GRB connection confirmed
  41. GRB 030329: Supernova Confirmed
  42. GRB030329: RTT150 optical observations
  43. GRB030329: Near Infrared Observations at Gunma
  44. GRB030329: HET spectroscopic monitoring
  45. Kiso observation of the GRB030329 at April 6
  46. GRB 030329, color evolution
  47. GRB030328, UBVRcIc field photometry
  48. GRB030329: Optical observcations
  49. GRB030329: BV photographic observations
  50. GRB 030329 Optical observations
  51. GRB 030329, color evolution
  52. GRB 030329: possible color change
  53. GRB030329: RTT150 optical observations
  54. GRB 030329: Supernova Spectrum Emerging
  55. GRB030329: Kiso B and R band observations
  56. GRB030329: RTT150 optical observation
  57. GRB030329: More AAVSO VR obs
  58. GRB030328: R upper limit after 6 hours by MASTER
  59. GRB 030329: BV photographic observations
  60. GRB 030329: SARA Optical Observations
  61. GRB 030329: SARA Optical Observations
  62. GRB030329, fading resumes
  63. GRB 030329, BVRI photometry
  64. GRB030329: Optical observations
  65. SDSS 0.5m PT observations of GRB030329 (correction)
  66. SDSS 0.5m PT observations of GRB030329
  67. GRB 030329, Optical observations
  68. GRB 030329, nearby galaxies
  69. GRB030329, cessation of fading
  70. GRB030329: final R-band light curve by MASTER
  71. GRB030329 - more 15 GHz radio data
  72. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  73. GRB 030329: Sub-millimeter detection
  74. GRB 030329: SARA Optical Observations
  75. GRB 030329: SARA Optical Observations
  76. OT GRB light curves and SN predictions
  77. GRB030329, optical observation
  78. GRB030329, optical observation
  79. GRB030329, new UBVRcIc field photometry
  80. GRB 030329, light curve and SN prediction
  81. GRB030329: optical observations at Tokyo Tech
  82. GRB 030329: optical observations
  83. GRB030329: multiple re-brightening phases
  84. GRB 030329, BRI photometry
  85. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  86. GRB 030329 , SPM optical observations
  87. GRB030329: Optical observations at Teramo
  88. GRB 030329: Radio observations at GMRT
  89. GRB030329: more 15GHz observations
  90. Further AAVSO V,B,R observations of GRB030329
  91. GRB 030329: Additional Mt. Laguna Optical Observations
  92. GRB 030329: SARA Optical Observations
  93. GRB 030329: Observations with ANDICAM
  94. GRB030329: Optical observations
  95. GRB030329: further optical photometry and evidence for a light curve discontinuity
  96. GRB 030329: Correction to GCN 2056
  97. GRB 030329: fitting parameters and re-brightening
  98. GRB 030329: KAIT optical photometry
  99. GRB030329 Further RBO Optical Observations
  100. triangulation of GRB 030331 (single error box)

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