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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"

26303 results found.

  1. GRB030429, possible optical counterpart
  2. GRB030501 localized by INTEGRAL
  3. GRB030425: CrAO optical observation
  4. IPN triangulation of GRB030429 (annulus)
  5. IPN triangulation of GRB030428 (two large error boxes)
  6. GRB 030324: Radio Observations
  7. GRB030329 observed as a sudden ionospheric disturbance (SID)
  8. IPN triangulation of GRB030426 (annulus)
  9. SNeIa AS THE POSSIBLE PROGENITORS OF SHORT-DURATION GRBs.
  10. IPN triangulation of GRB030425 (single error box)
  11. GRB030329, SPM optical observations
  12. IPN triangulation of GRB030422C (annulus)
  13. IPN triangulation of GRB030422B (annulus)
  14. GRB 030329: wide-field photograph by R. Tamura 1 hr after the burst
  15. GRB030329: optical polarization
  16. IPN triangulation of GRB030422 (two large error boxes)
  17. GRB030329, optical observation
  18. IPN triangulation of GRB030421 (annulus)
  19. MASTER:optical observations probable GRB030414
  20. GRB030329: 444 AAVSO Measurements
  21. IPN triangulation of GRB030419 (annulus)
  22. ROTSE-III prompt optical detections of GRB 030418
  23. GRB030418: Upper limits from recent and historical observations.
  24. GRB 030418: Optical afterglow
  25. GRB 030329 OT position
  26. GRB030329: Optical Observations
  27. GRB030329, UBVRI polarimetry, R-polarization
  28. GRB 030329: SARA Optical Observations
  29. OT GRB 030329: early spectrum
  30. GRB030329: VR Photometry at TNG
  31. IPN triangulation of GRB030414 (small error box)
  32. IPN triangulation of GRB030413 (small error box)
  33. IPN triangulation of GRB030410 (annulus)
  34. GRB 030329 and SN 2003dh
  35. GRB030329, optical position
  36. GRB 030329 VLBA Observations
  37. IPN triangulation of GRB030406 (small error box)
  38. IPN triangulation of GRB050403 (small error box)
  39. IPN triangulation of GRB030403 (annulus)
  40. GRB 030329: BVRI photometry at Asiago
  41. GRB 030329, light curve flattens
  42. GRB 030329: Supernova Confirmed
  43. GRB030329: HET spectroscopic monitoring
  44. GRB 030329, color evolution
  45. GRB030329: Optical observcations
  46. GRB030329: BV photographic observations
  47. GRB 030329, color evolution
  48. GRB 030329: possible color change
  49. GRB 030329: Supernova Spectrum Emerging
  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. GRB 030329, BVRI photometry
  56. GRB030329: Optical observations
  57. SDSS 0.5m PT observations of GRB030329 (correction)
  58. SDSS 0.5m PT observations of GRB030329
  59. GRB030329, cessation of fading
  60. GRB030329: final R-band light curve by MASTER
  61. GRB 030329: SARA Optical Observations
  62. GRB 030329: SARA Optical Observations
  63. GRB030329, optical observation
  64. GRB030329, optical observation
  65. GRB030329, new UBVRcIc field photometry
  66. GRB 030329, light curve and SN prediction
  67. GRB030329: multiple re-brightening phases
  68. GRB 030329, BRI photometry
  69. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  70. GRB030329: Optical observations at Teramo
  71. Further AAVSO V,B,R observations of GRB030329
  72. GRB 030329: SARA Optical Observations
  73. GRB030329: Optical observations
  74. GRB030329: further optical photometry and evidence for a light curve discontinuity
  75. GRB 030329: fitting parameters and re-brightening
  76. GRB 030329: KAIT optical photometry
  77. GRB030329 Further RBO Optical Observations
  78. triangulation of GRB 030331 (single error box)
  79. GRB030329 - OT rebrightens
  80. GRB 030329: SARA Optical Observations
  81. AAVSO V & R observations of GRB030329
  82. IPN triangulation of GRB030331 (annulus)
  83. GRB 030329: optical observations
  84. IPN triangulation of GRB030329b (large error box)
  85. GRB 030329, optical spectroscopy
  86. GRB 030329: fading X-ray afterglow with RXTE
  87. GRB030329: Optical observations
  88. GRB 030329, R-band light curve
  89. GRB030329 - OT brightens
  90. GRB 030329: OT observations at Kanazawa
  91. GRB 030329 RBO V Optical Observations
  92. GRB 030329, optical photometry
  93. 030331 NOT A GRB
  94. GRB 030328, optical photometry
  95. GRB030329: R band light curve by MASTER
  96. GRB030329 - Light curve flattening
  97. GRB 030329: SARA Optical Observations
  98. GRB030329 - near contemporaneous optical limits from CONCAM
  99. GRB030329: R and B observations
  100. GRB 030329, optical observations

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