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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"

20968 results found.

  1. GRB030329 - OT brightens
  2. GRB 030329: OT observations at Kanazawa
  3. GRB 030329 RBO V Optical Observations
  4. GRB 030329, optical photometry
  5. GRB030329: Near Infrared Observations
  6. GRB 030324: Optical and NIR Observations
  7. GRB 030328, optical photometry
  8. GRB030329: R band light curve by MASTER
  9. GRB030329 - Light curve flattening
  10. GRB 030329: SARA Optical Observations
  11. GRB 030324, optical search
  12. GRB030329: R and B observations
  13. GRB 030329, optical observations
  14. GRB030329: Optical observations
  15. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  16. GRB 030329: Light curve observed during the change of its slope.
  17. GRB030329, SPM optical observations
  18. GRB030329: ROTSE network observes steepening of decay curve
  19. GRB 030329: Optical decay and synthesis
  20. GRB030329 optical observations
  21. GRB030329: optical spectroscopy with the TNG
  22. GRB 030329: Radio Observations
  23. GRB 030329, optical spectroscopy
  24. GRB 030329: still bright
  25. GRB 030329: visual observations
  26. GRB 030329: Upper limit from 5.6 hours before trigger
  27. GRB030328: X-ray Afterglow Observed with Chandra
  28. GRB030329: Optical observations
  29. GRB 030329, R-band observations, supplement
  30. GRB030329 optical observations
  31. GRB030329:optical observations by MASTER
  32. GRB 030329: optical observations
  33. GRB 030329, R-band observations
  34. GRB030329: Upper limits from recent and historical observations.
  35. GRB 030329: Optical Afterglow Observations
  36. GRB 030328 Optical Observations
  37. GRB030328: Decay index
  38. GRB 030328: Optical observations
  39. GRB 030328: optical observations
  40. GRB 030329: Optical afterglow fading
  41. GRB 030329 follow-up
  42. GRB 030329: Optical afterglow candidate
  43. GRB 030328: OT photometry
  44. GRB030328: optical spectroscopy at TNG
  45. GRB030328: optical photometry at the TNG
  46. GRB 030328, optical spectroscopy
  47. GRB 030328, optical observations
  48. GRB 030328: Optical observations
  49. GRB 030328: Optical afterglow candidate
  50. GRB030323 optical observations
  51. GRB 030323: SARA Optical Observations
  52. GRB030324, optical observations
  53. GRB030324, optical observations
  54. GRB 030324: TAROT optical observations
  55. GRB030323: V, R, I photometry
  56. GRB 030324 (HETE #2641): Optical observations
  57. GRB030324, Optical Observations
  58. GRB030323: Upper limits from recent and historical observations.
  59. GRB030323, optical observations
  60. GRB030324, BVRcIc field photometry
  61. GRB030323, possible optical counterpart
  62. GRB030323, BVRcIc field calibration
  63. GRB 030324 optical observations
  64. GRB 030320: Optical Observations
  65. GRB 030324, optical observations
  66. GRB030226, addendum to GCN 1892
  67. GRB 030226 Optical observations
  68. GRB030226: Optical observations at Asiago
  69. GRB 030226: Optical observations
  70. GRB 030227: Optical observations
  71. GRB030226, BVRc observations
  72. GRB 030226, further optical/NIR imaging
  73. GRB030227, optical observations
  74. GRB 030226: Ic Observations
  75. GRB 030228, optical observations
  76. GRB 030226: Steep Decline
  77. GRB 030227: Confirmed Optical Afterglow (S1-A)
  78. GRB 030226: R band polarimetric observations
  79. GRB 030226: Optical observations
  80. GRB030227:Optical observations
  81. GRB 20030226: Upper limits from recent and historical observations
  82. GRB 030227, possible optical counterpart of XMM-Newton source
  83. GRB 030226, optical observations
  84. GRB030227: Kiso optical observations
  85. GRB 030226, optical light curve
  86. GRB030226: optical observation
  87. GRB030226: ESI spectroscopy
  88. GRB 030226 simultaneous optical observations
  89. GRB 030226, optical observations
  90. GRB030226: optical observations and refined redshift
  91. GRB030226: Optical decay index
  92. GRB 030226, optical observations
  93. GRB030226: Candidate optical afterglow
  94. GRB 030217: Optical Observations at 4, 5, and 6 Days
  95. GRB030217: optical observations
  96. GRB030115, WSRT radio observations - correction to GCN 1864
  97. GRB 030131: marginal optical detection
  98. GRB030115, WSRT radio observations
  99. GRB 030204: Optical Observations
  100. GRB020819: Kiso R and I band observations

Advanced

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