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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"

32504 results found.

  1. AAVSO V & R observations of GRB030329
  2. GRB 030329: optical observations
  3. IPN triangulation of GRB030329b (large error box)
  4. GRB 030329: beginning of the new fading phase in optical band
  5. GRB 030329, optical spectroscopy
  6. GRB 030329: fading X-ray afterglow with RXTE
  7. GRB 030329: optical photometry
  8. GRB030329: Optical observations
  9. Photometry of GRB030329 - Constant OT Magnitude
  10. GRB 030329, R-band light curve
  11. GRB 030329: further optical observations
  12. GRB030329 - OT brightens
  13. GRB 030329: OT observations at Kanazawa
  14. GRB030329 15 GHz radio observation
  15. GRB 030329 RBO V Optical Observations
  16. GRB 030329, optical photometry
  17. GRB030329: Near Infrared Observations
  18. GRB 030324: Optical and NIR Observations
  19. GRB 030328, optical photometry
  20. GRB030329: R band light curve by MASTER
  21. GRB030329 - Light curve flattening
  22. GRB 030329: SARA Optical Observations
  23. GRB 030324, optical search
  24. GRB030329 - near contemporaneous optical limits from CONCAM
  25. GRB030329: R and B observations
  26. GRB 030329, optical observations
  27. GRB030329: Optical observations
  28. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  29. GRB030329a: detection by Konus-Wind
  30. GRB 030329: Light curve observed during the change of its slope.
  31. GRB030329, BVRcIc field photometry
  32. GRB030329, SPM optical observations
  33. GRB 030329: Optical Decay
  34. Redshift of GRB 030329
  35. GRB030329: ROTSE network observes steepening of decay curve
  36. GRB 030329, optical photometry
  37. GRB 030329: Optical decay and synthesis
  38. GRB030329 optical observations
  39. GRB030329: optical spectroscopy with the TNG
  40. GRB 030329: Radio Observations
  41. GRB 030329, optical spectroscopy
  42. GRB 030329: still bright
  43. GRB 030329: Optical pre-Imaging
  44. GRB 030329: visual observations
  45. GRB 030329: Upper limit from 5.6 hours before trigger
  46. GRB030328: R optical observation
  47. GRB030328: X-ray Afterglow Observed with Chandra
  48. GRB 030323: Gemini South VRI obsevations.
  49. GRB030329: Optical observations
  50. GRB030329:optical observations by MASTER
  51. GRB 030329: optical observations
  52. GRB 030329, R-band observations
  53. GRB 030329: OT B and R photometry, decline rate
  54. GRB030329: Upper limits from recent and historical observations.
  55. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  56. GRB 030329: Optical Afterglow Observations
  57. GRB 030329: precise position from Kyoto images
  58. GRB 030328 Optical Observations
  59. GRB030328: Decay index
  60. GRB 030328: Optical observations
  61. GRB 030328: optical observations
  62. GRB 030329: Optical afterglow fading
  63. GRB 030328: OT photometry
  64. GRB030328: optical spectroscopy at TNG
  65. GRB030328: optical photometry at the TNG
  66. VLT spectra of GRB 030328
  67. GRB 030328, optical spectroscopy
  68. GRB 030328, optical observations
  69. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  70. GRB 030328: Optical observations
  71. GRB 030328: Finding chart
  72. GRB030323 optical observations
  73. GRB030131, BVRcIc field photometry
  74. IPN triangulation of GRB030325 (final analysis)
  75. GRB030323: Detection on 2003/03/24
  76. GRB 030323: SARA Optical Observations
  77. IPN triangulation of GRB030325 (single small error box)
  78. GRB030324, optical observations
  79. GRB030324, optical observations
  80. GRB 030324: TAROT optical observations
  81. GRB030323: V, R, I photometry
  82. GRB 030324 (HETE #2641): Optical observations
  83. GRB030324, Optical Observations
  84. GRB030323: Upper limits from recent and historical observations.
  85. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  86. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  87. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  88. VLT/FORS2 spectra of GRB 030323
  89. GRB030323, ROTSE-III detection of possible optical counterpart
  90. GRB030323, optical observations
  91. GRB030323, possible optical counterpart
  92. GRB 030324 optical observations
  93. GRB 030320: Optical Observations
  94. IPN triangulation of GRB030320 (small error box)
  95. IPN triangulation of GRB030320
  96. GRB030226, addendum to GCN 1892
  97. IPN upper limit to a GRB associated with SN2003L
  98. GRB 030227: Optical limit at RIKEN
  99. GRB 030226 Optical observations
  100. IPN triangulation of GRB030306 (single small error box - REVISED)

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