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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"

36143 results found.

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

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