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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"

36145 results found.

  1. GRB030329: 444 AAVSO Measurements
  2. IPN triangulation of GRB030419 (annulus)
  3. MASTER:optical observations GRB030416
  4. ROTSE-III prompt optical detections of GRB 030418
  5. GRB030418: Upper limits from recent and historical observations.
  6. GRB030418: Kiso near infrared observations
  7. GRB 030418: Optical afterglow
  8. GRB 030418: Finder for afterglow candidate
  9. GRB 030418: Optical afterglow candidate
  10. GRB 030329 OT position
  11. OT GRB 030329: early UBVRcIc spectral evolution
  12. GRB030329, UBVRI polarimetry, R-polarization
  13. GRB 030329: SARA Optical Observations
  14. OT GRB 030329: early spectrum
  15. GRB030329: VR Photometry at TNG
  16. GRB030324: Candidate Optical Afterglow (Erratum)
  17. GRB030324: Candidate Optical Afterglow
  18. IPN triangulation of GRB030414 (small error box)
  19. GRB 030413: Optical Observations
  20. GRB 030329 Rc observations
  21. IPN triangulation of GRB030413 (small error box)
  22. IPN triangulation of GRB030410 (annulus)
  23. Superluminal motion in GRB 030329 (Correction)
  24. Superluminal motion in GRB 030329
  25. GRB 030329 and SN 2003dh
  26. GRB030329, optical position
  27. GRB 030329 VLBA Observations
  28. IPN triangulation of GRB030406 (small error box)
  29. IPN triangulation of GRB050403 (small error box)
  30. IPN triangulation of GRB030403 (annulus)
  31. GRB 030329: BVRI photometry at Asiago
  32. GRB 030329, light curve flattens
  33. GRB 030329: VLT V-band photometry
  34. If the SN/GRB connection confirmed
  35. GRB 030329: Supernova Confirmed
  36. GRB030329: RTT150 optical observations
  37. GRB030329: Near Infrared Observations at Gunma
  38. GRB030329: HET spectroscopic monitoring
  39. Kiso observation of the GRB030329 at April 6
  40. GRB 030329, color evolution
  41. GRB030328, UBVRcIc field photometry
  42. GRB 030329 Optical observations
  43. GRB 030329, color evolution
  44. GRB 030329: possible color change
  45. GRB030329: RTT150 optical observations
  46. GRB 030329: Supernova Spectrum Emerging
  47. GRB030329: Kiso B and R band observations
  48. GRB030329: RTT150 optical observation
  49. GRB030329: More AAVSO VR obs
  50. GRB030328: R upper limit after 6 hours by MASTER
  51. GRB 030329: BV photographic observations
  52. GRB 030329: SARA Optical Observations
  53. GRB 030329: SARA Optical Observations
  54. GRB030329, fading resumes
  55. GRB 030329, BVRI photometry
  56. SDSS 0.5m PT observations of GRB030329 (correction)
  57. SDSS 0.5m PT observations of GRB030329
  58. GRB 030329, Optical observations
  59. GRB 030329, nearby galaxies
  60. GRB030329, cessation of fading
  61. GRB030329 Radio 23/43/90 GHz observations at Nobeyama
  62. GRB 030329: Sub-millimeter detection
  63. GRB 030329: SARA Optical Observations
  64. GRB 030329: SARA Optical Observations
  65. OT GRB light curves and SN predictions
  66. GRB030329, optical observation
  67. GRB030329, new UBVRcIc field photometry
  68. GRB 030329, light curve and SN prediction
  69. GRB030329: optical observations at Tokyo Tech
  70. GRB 030329: optical observations
  71. GRB030329: multiple re-brightening phases
  72. GRB 030329, BRI photometry
  73. GRB 030329 , SPM optical observations
  74. GRB 030329: Radio observations at GMRT
  75. Further AAVSO V,B,R observations of GRB030329
  76. GRB 030329: Additional Mt. Laguna Optical Observations
  77. GRB 030329: SARA Optical Observations
  78. GRB 030329: Observations with ANDICAM
  79. GRB030329: further optical photometry and evidence for a light curve discontinuity
  80. GRB 030329: Correction to GCN 2056
  81. GRB 030329: fitting parameters and re-brightening
  82. GRB 030329: KAIT optical photometry
  83. GRB030329 Further RBO Optical Observations
  84. triangulation of GRB 030331 (single error box)
  85. GRB030329 - OT rebrightens
  86. GRB 030329: SARA Optical Observations
  87. AAVSO V & R observations of GRB030329
  88. IPN triangulation of GRB030331 (annulus)
  89. GRB 030329: optical observations
  90. IPN triangulation of GRB030329b (large error box)
  91. GRB 030329: beginning of the new fading phase in optical band
  92. GRB 030329, optical spectroscopy
  93. GRB 030329: fading X-ray afterglow with RXTE
  94. GRB 030329: optical photometry
  95. Photometry of GRB030329 - Constant OT Magnitude
  96. GRB 030329, R-band observations
  97. GRB 030329, R-band light curve
  98. GRB 030329: further optical observations
  99. GRB030329 - OT brightens
  100. GRB 030329: OT observations at Kanazawa

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