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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"

22056 results found.

  1. GRB 030329: Optical decay and synthesis
  2. GRB030329 optical observations
  3. GRB030329: optical spectroscopy with the TNG
  4. GRB 030329: Radio Observations
  5. GRB 030329: Optical pre-Imaging
  6. GRB 030329: visual observations
  7. GRB 030329: Upper limit from 5.6 hours before trigger
  8. GRB030328: X-ray Afterglow Observed with Chandra
  9. GRB030329: Optical observations
  10. GRB 030329, R-band observations, supplement
  11. GRB030329 optical observations
  12. GRB030329:optical observations by MASTER
  13. GRB 030329: optical observations
  14. GRB 030329, R-band observations
  15. GRB030329: Upper limits from recent and historical observations.
  16. GRB 030329: Optical Afterglow Observations
  17. GRB 030328 Optical Observations
  18. GRB030328: Decay index
  19. GRB 030328: Optical observations
  20. GRB 030328: optical observations
  21. GRB 030329: Optical afterglow fading
  22. GRB 030329 follow-up
  23. GRB 030329: Optical afterglow candidate
  24. GRB 030328: OT photometry
  25. GRB030328: optical spectroscopy at TNG
  26. GRB030328: optical photometry at the TNG
  27. GRB 030328, optical observations
  28. GRB 030328: Optical observations
  29. GRB 030328: Optical afterglow candidate
  30. GRB030323 optical observations
  31. GRB030323: Detection on 2003/03/24
  32. GRB 030323: SARA Optical Observations
  33. GRB030324, optical observations
  34. GRB030324, optical observations
  35. GRB 030324: TAROT optical observations
  36. GRB030323: V, R, I photometry
  37. GRB 030324 (HETE #2641): Optical observations
  38. GRB030324, Optical Observations
  39. GRB030323: Upper limits from recent and historical observations.
  40. GRB030323, ROTSE-III detection of possible optical counterpart
  41. GRB030323, optical observations
  42. GRB030324, BVRcIc field photometry
  43. GRB030323, possible optical counterpart
  44. GRB030323, BVRcIc field calibration
  45. GRB 030324 optical observations
  46. GRB 030320: Optical Observations
  47. GRB 030324, optical observations
  48. Possible GRB 030320 localized by INTEGRAL
  49. GRB030226, addendum to GCN 1892
  50. GRB 030226 Optical observations
  51. GRB030226: Optical observations at Asiago
  52. IPN triangulation of GRB030306 (intense; annulus only so far)
  53. GRB 030226: Optical observations
  54. GRB 030227: Optical observations
  55. GRB030226, BVRc observations
  56. GRB 030226, further optical/NIR imaging
  57. GRB030227, optical observations
  58. GRB 030226: Ic Observations
  59. GRB 030228, optical observations
  60. GRB 030226: Steep Decline
  61. GRB 030226: R band polarimetric observations
  62. GRB 030226: Optical observations
  63. GRB030227:Optical observations
  64. GRB 20030226: Upper limits from recent and historical observations
  65. GRB 030227, possible optical counterpart of XMM-Newton source
  66. GRB030227 - faint tentative OT candidate
  67. GRB 030226, optical observations
  68. GRB030227: Kiso optical observations
  69. GRB 030226, optical light curve
  70. GRB030226: optical observation
  71. GRB030226: ESI spectroscopy
  72. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  73. GRB 030226 simultaneous optical observations
  74. GRB 030226, optical observations
  75. GRB030226: optical observations and refined redshift
  76. GRB030226: Optical decay index
  77. GRB 030226, optical observations
  78. GRB030226: Candidate optical afterglow
  79. GRB 030217: Optical Observations at 4, 5, and 6 Days
  80. GRB030217: optical observations
  81. GRB030115, WSRT radio observations - correction to GCN 1864
  82. GRB 030131: marginal optical detection
  83. GRB030115, WSRT radio observations
  84. GRB 030204: Optical Observations
  85. GRB020819: Kiso R and I band observations
  86. GRB030131: Candidate Optical Afterglow
  87. GRB 030115: Optical Observations
  88. GRB 030204, optical observations
  89. GRB 030131, optical observations
  90. GRB030131: Optical limits for corrected position
  91. GRB 030131: afterglow candidate
  92. GRB 030115, late-time optical observations
  93. Type Ic SN2003L (SN/GRB?), optical spectrum
  94. GRB030131: Kiso Observations
  95. GRB 020819: Host galaxy at Radio Position
  96. GRB030131: Optical limit
  97. GRB 030131 optical observations
  98. GRB 030131 optical observations
  99. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  100. Type Ic SN2003L (SN/GRB?) Radio Observations

Advanced

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