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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"

32506 results found.

  1. GRB030329 - OT rebrightens
  2. GRB 030329: SARA Optical Observations
  3. AAVSO V & R observations of GRB030329
  4. GRB 030329: optical observations
  5. IPN triangulation of GRB030329b (large error box)
  6. GRB 030329: beginning of the new fading phase in optical band
  7. GRB 030329, optical spectroscopy
  8. GRB 030329: fading X-ray afterglow with RXTE
  9. GRB 030329: optical photometry
  10. GRB030329: Optical observations
  11. Photometry of GRB030329 - Constant OT Magnitude
  12. GRB 030329, R-band light curve
  13. GRB 030329: further optical observations
  14. GRB030329 - OT brightens
  15. GRB 030329: OT observations at Kanazawa
  16. GRB030329 15 GHz radio observation
  17. GRB 030329 RBO V Optical Observations
  18. GRB 030329, optical photometry
  19. GRB030329: Near Infrared Observations
  20. GRB 030324: Optical and NIR Observations
  21. GRB 030328, optical photometry
  22. GRB030329: R band light curve by MASTER
  23. GRB030329 - Light curve flattening
  24. GRB 030329: SARA Optical Observations
  25. GRB 030324, optical search
  26. GRB030329 - near contemporaneous optical limits from CONCAM
  27. GRB030329: R and B observations
  28. GRB 030329, optical observations
  29. GRB030329: Optical observations
  30. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  31. GRB030329a: detection by Konus-Wind
  32. GRB 030329: Light curve observed during the change of its slope.
  33. GRB030329, BVRcIc field photometry
  34. GRB030329, SPM optical observations
  35. GRB 030329: Optical Decay
  36. Redshift of GRB 030329
  37. GRB030329: ROTSE network observes steepening of decay curve
  38. GRB 030329, optical photometry
  39. GRB 030329: Optical decay and synthesis
  40. GRB030329 optical observations
  41. GRB030329: optical spectroscopy with the TNG
  42. GRB 030329: Radio Observations
  43. GRB 030329, optical spectroscopy
  44. GRB 030329: still bright
  45. GRB 030329: Optical pre-Imaging
  46. GRB 030329: visual observations
  47. GRB 030329: Upper limit from 5.6 hours before trigger
  48. GRB030328: R optical observation
  49. GRB030328: X-ray Afterglow Observed with Chandra
  50. GRB 030323: Gemini South VRI obsevations.
  51. GRB030329: Optical observations
  52. GRB030329:optical observations by MASTER
  53. GRB 030329: optical observations
  54. GRB 030329, R-band observations
  55. GRB 030329: OT B and R photometry, decline rate
  56. GRB030329: Upper limits from recent and historical observations.
  57. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  58. GRB 030329: Optical Afterglow Observations
  59. GRB 030329: precise position from Kyoto images
  60. GRB 030328 Optical Observations
  61. GRB030328: Decay index
  62. GRB 030328: Optical observations
  63. GRB 030328: optical observations
  64. GRB 030329: Optical afterglow fading
  65. GRB 030328: OT photometry
  66. GRB030328: optical spectroscopy at TNG
  67. GRB030328: optical photometry at the TNG
  68. VLT spectra of GRB 030328
  69. GRB 030328, optical spectroscopy
  70. GRB 030328, optical observations
  71. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  72. GRB 030328: Optical observations
  73. GRB 030328: Finding chart
  74. GRB030323 optical observations
  75. GRB030131, BVRcIc field photometry
  76. IPN triangulation of GRB030325 (final analysis)
  77. GRB030323: Detection on 2003/03/24
  78. GRB 030323: SARA Optical Observations
  79. IPN triangulation of GRB030325 (single small error box)
  80. GRB030324, optical observations
  81. GRB030324, optical observations
  82. GRB 030324: TAROT optical observations
  83. GRB030323: V, R, I photometry
  84. GRB 030324 (HETE #2641): Optical observations
  85. GRB030324, Optical Observations
  86. GRB030323: Upper limits from recent and historical observations.
  87. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  88. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  89. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  90. VLT/FORS2 spectra of GRB 030323
  91. GRB030323, ROTSE-III detection of possible optical counterpart
  92. GRB030323, optical observations
  93. GRB030323, possible optical counterpart
  94. GRB 030324 optical observations
  95. GRB 030320: Optical Observations
  96. IPN triangulation of GRB030320 (small error box)
  97. IPN triangulation of GRB030320
  98. GRB030226, addendum to GCN 1892
  99. IPN upper limit to a GRB associated with SN2003L
  100. GRB 030227: Optical limit at RIKEN

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