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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"

32508 results found.

  1. GRB030329 Further RBO Optical Observations
  2. triangulation of GRB 030331 (single error box)
  3. GRB030329 - OT rebrightens
  4. GRB 030329: SARA Optical Observations
  5. AAVSO V & R observations of GRB030329
  6. GRB 030329: optical observations
  7. IPN triangulation of GRB030329b (large error box)
  8. GRB 030329: beginning of the new fading phase in optical band
  9. GRB 030329, optical spectroscopy
  10. GRB 030329: fading X-ray afterglow with RXTE
  11. GRB 030329: optical photometry
  12. GRB030329: Optical observations
  13. Photometry of GRB030329 - Constant OT Magnitude
  14. GRB 030329, R-band light curve
  15. GRB 030329: further optical observations
  16. GRB030329 - OT brightens
  17. GRB 030329: OT observations at Kanazawa
  18. GRB030329 15 GHz radio observation
  19. GRB 030329 RBO V Optical Observations
  20. GRB 030329, optical photometry
  21. GRB030329: Near Infrared Observations
  22. GRB 030324: Optical and NIR Observations
  23. GRB 030328, optical photometry
  24. GRB030329: R band light curve by MASTER
  25. GRB030329 - Light curve flattening
  26. GRB 030329: SARA Optical Observations
  27. GRB 030324, optical search
  28. GRB030329 - near contemporaneous optical limits from CONCAM
  29. GRB030329: R and B observations
  30. GRB 030329, optical observations
  31. GRB030329: Optical observations
  32. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  33. GRB030329a: detection by Konus-Wind
  34. GRB 030329: Light curve observed during the change of its slope.
  35. GRB030329, BVRcIc field photometry
  36. GRB030329, SPM optical observations
  37. GRB 030329: Optical Decay
  38. Redshift of GRB 030329
  39. GRB030329: ROTSE network observes steepening of decay curve
  40. GRB 030329, optical photometry
  41. GRB 030329: Optical decay and synthesis
  42. GRB030329 optical observations
  43. GRB030329: optical spectroscopy with the TNG
  44. GRB 030329: Radio Observations
  45. GRB 030329, optical spectroscopy
  46. GRB 030329: still bright
  47. GRB 030329: Optical pre-Imaging
  48. GRB 030329: visual observations
  49. GRB 030329: Upper limit from 5.6 hours before trigger
  50. GRB030328: R optical observation
  51. GRB030328: X-ray Afterglow Observed with Chandra
  52. GRB 030323: Gemini South VRI obsevations.
  53. GRB030329: Optical observations
  54. GRB030329:optical observations by MASTER
  55. GRB 030329: optical observations
  56. GRB 030329, R-band observations
  57. GRB 030329: OT B and R photometry, decline rate
  58. GRB030329: Upper limits from recent and historical observations.
  59. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  60. GRB 030329: Optical Afterglow Observations
  61. GRB 030329: precise position from Kyoto images
  62. GRB 030328 Optical Observations
  63. GRB030328: Decay index
  64. GRB 030328: Optical observations
  65. GRB 030328: optical observations
  66. GRB 030329: Optical afterglow fading
  67. GRB 030328: OT photometry
  68. GRB030328: optical spectroscopy at TNG
  69. GRB030328: optical photometry at the TNG
  70. VLT spectra of GRB 030328
  71. GRB 030328, optical spectroscopy
  72. GRB 030328, optical observations
  73. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  74. GRB 030328: Optical observations
  75. GRB 030328: Finding chart
  76. GRB030323 optical observations
  77. GRB030131, BVRcIc field photometry
  78. IPN triangulation of GRB030325 (final analysis)
  79. GRB030323: Detection on 2003/03/24
  80. GRB 030323: SARA Optical Observations
  81. IPN triangulation of GRB030325 (single small error box)
  82. GRB030324, optical observations
  83. GRB030324, optical observations
  84. GRB 030324: TAROT optical observations
  85. GRB030323: V, R, I photometry
  86. GRB 030324 (HETE #2641): Optical observations
  87. GRB030324, Optical Observations
  88. GRB030323: Upper limits from recent and historical observations.
  89. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  90. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  91. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  92. VLT/FORS2 spectra of GRB 030323
  93. GRB030323, ROTSE-III detection of possible optical counterpart
  94. GRB030323, optical observations
  95. GRB030323, possible optical counterpart
  96. GRB 030324 optical observations
  97. GRB 030320: Optical Observations
  98. IPN triangulation of GRB030320 (small error box)
  99. IPN triangulation of GRB030320
  100. GRB030226, addendum to GCN 1892

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