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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"

36146 results found.

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

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