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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"

20967 results found.

  1. GRB 030329: OT observations at Kanazawa
  2. GRB 030329 RBO V Optical Observations
  3. GRB 030329, optical photometry
  4. GRB030329: Near Infrared Observations
  5. GRB 030324: Optical and NIR Observations
  6. GRB 030328, optical photometry
  7. GRB030329: R band light curve by MASTER
  8. GRB030329 - Light curve flattening
  9. GRB 030329: SARA Optical Observations
  10. GRB 030324, optical search
  11. GRB030329: R and B observations
  12. GRB 030329, optical observations
  13. GRB030329: Optical observations
  14. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  15. GRB 030329: Light curve observed during the change of its slope.
  16. GRB030329, SPM optical observations
  17. GRB030329: ROTSE network observes steepening of decay curve
  18. GRB 030329: Optical decay and synthesis
  19. GRB030329 optical observations
  20. GRB030329: optical spectroscopy with the TNG
  21. GRB 030329: Radio Observations
  22. GRB 030329, optical spectroscopy
  23. GRB 030329: still bright
  24. GRB 030329: visual observations
  25. GRB 030329: Upper limit from 5.6 hours before trigger
  26. GRB030328: X-ray Afterglow Observed with Chandra
  27. GRB030329: Optical observations
  28. GRB 030329, R-band observations, supplement
  29. GRB030329 optical observations
  30. GRB030329:optical observations by MASTER
  31. GRB 030329: optical observations
  32. GRB 030329, R-band observations
  33. GRB030329: Upper limits from recent and historical observations.
  34. GRB 030329: Optical Afterglow Observations
  35. GRB 030328 Optical Observations
  36. GRB030328: Decay index
  37. GRB 030328: Optical observations
  38. GRB 030328: optical observations
  39. GRB 030329: Optical afterglow fading
  40. GRB 030329 follow-up
  41. GRB 030329: Optical afterglow candidate
  42. GRB 030328: OT photometry
  43. GRB030328: optical spectroscopy at TNG
  44. GRB030328: optical photometry at the TNG
  45. GRB 030328, optical spectroscopy
  46. GRB 030328, optical observations
  47. GRB 030328: Optical observations
  48. GRB 030328: Optical afterglow candidate
  49. GRB030323 optical observations
  50. GRB 030323: SARA Optical Observations
  51. GRB030324, optical observations
  52. GRB030324, optical observations
  53. GRB 030324: TAROT optical observations
  54. GRB030323: V, R, I photometry
  55. GRB 030324 (HETE #2641): Optical observations
  56. GRB030324, Optical Observations
  57. GRB030323: Upper limits from recent and historical observations.
  58. GRB030323, optical observations
  59. GRB030324, BVRcIc field photometry
  60. GRB030323, possible optical counterpart
  61. GRB030323, BVRcIc field calibration
  62. GRB 030324 optical observations
  63. GRB 030320: Optical Observations
  64. GRB 030324, optical observations
  65. GRB030226, addendum to GCN 1892
  66. GRB 030226 Optical observations
  67. GRB030226: Optical observations at Asiago
  68. GRB 030226: Optical observations
  69. GRB 030227: Optical observations
  70. GRB030226, BVRc observations
  71. GRB 030226, further optical/NIR imaging
  72. GRB030227, optical observations
  73. GRB 030226: Ic Observations
  74. GRB 030228, optical observations
  75. GRB 030226: Steep Decline
  76. GRB 030227: Confirmed Optical Afterglow (S1-A)
  77. GRB 030226: R band polarimetric observations
  78. GRB 030226: Optical observations
  79. GRB030227:Optical observations
  80. GRB 20030226: Upper limits from recent and historical observations
  81. GRB 030227, possible optical counterpart of XMM-Newton source
  82. GRB 030226, optical observations
  83. GRB030227: Kiso optical observations
  84. GRB 030226, optical light curve
  85. GRB030226: optical observation
  86. GRB030226: ESI spectroscopy
  87. GRB 030226 simultaneous optical observations
  88. GRB 030226, optical observations
  89. GRB030226: optical observations and refined redshift
  90. GRB030226: Optical decay index
  91. GRB 030226, optical observations
  92. GRB030226: Candidate optical afterglow
  93. GRB 030217: Optical Observations at 4, 5, and 6 Days
  94. GRB030217: optical observations
  95. GRB030115, WSRT radio observations - correction to GCN 1864
  96. GRB 030131: marginal optical detection
  97. GRB030115, WSRT radio observations
  98. GRB 030204: Optical Observations
  99. GRB020819: Kiso R and I band observations
  100. GRB030131: Candidate Optical Afterglow

Advanced

Download all Circulars as a .tar.gz archive (updated once a day):
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