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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"

37555 results found.

  1. AAVSO V & R observations of GRB030329
  2. IPN triangulation of GRB030331 (annulus)
  3. GRB 030329: optical observations
  4. IPN triangulation of GRB030329b (large error box)
  5. GRB 030329: beginning of the new fading phase in optical band
  6. GRB 030329, optical spectroscopy
  7. GRB 030329: fading X-ray afterglow with RXTE
  8. GRB 030329: optical photometry
  9. Photometry of GRB030329 - Constant OT Magnitude
  10. GRB 030329, R-band observations
  11. GRB 030329, R-band light curve
  12. GRB 030329: further optical observations
  13. GRB030329 - OT brightens
  14. GRB 030329: OT observations at Kanazawa
  15. GRB030329 15 GHz radio observation
  16. GRB 030329 RBO V Optical Observations
  17. GRB 030329, optical photometry
  18. GRB030329: Near Infrared Observations
  19. 030331 NOT A GRB
  20. INTEGRAL GRB 030331
  21. GRB 030324: Optical and NIR Observations
  22. GRB 030328, optical photometry
  23. GRB030329: R band light curve by MASTER
  24. GRB030329 - Light curve flattening
  25. GRB 030329: SARA Optical Observations
  26. GRB 030324, optical search
  27. GRB030329 - near contemporaneous optical limits from CONCAM
  28. GRB 030329, optical observations
  29. GRB 030329: Light curve observed during the change of its slope.
  30. GRB030329, BVRcIc field photometry
  31. GRB030329, SPM optical observations
  32. GRB 030329: Optical Decay
  33. Redshift of GRB 030329
  34. GRB030329: ROTSE network observes steepening of decay curve
  35. GRB 030329, optical photometry
  36. GRB 030329: Optical decay and synthesis
  37. GRB 030329: Radio Observations
  38. GRB 030329, optical spectroscopy
  39. GRB 030329: still bright
  40. GRB 030329: Optical pre-Imaging
  41. GRB 030329: visual observations
  42. GRB 030329: Upper limit from 5.6 hours before trigger
  43. GRB030328: R optical observation
  44. GRB 030323: Gemini South VRI obsevations.
  45. GRB030329: Optical observations
  46. GRB 030329, R-band observations, supplement
  47. GRB030329:optical observations by MASTER
  48. GRB 030329: optical observations
  49. GRB 030329, R-band observations
  50. GRB 030329: OT B and R photometry, decline rate
  51. GRB030329: Upper limits from recent and historical observations.
  52. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  53. RXTE detection of GRB 030329 afterglow
  54. GRB 030329: Optical Afterglow Observations
  55. GRB 030329: precise position from Kyoto images
  56. GRB 030328 Optical Observations
  57. GRB 030328: Optical observations
  58. GRB 030328: optical observations
  59. GRB 030329: Optical afterglow fading
  60. GRB 030329 follow-up
  61. GRB 030329: Optical afterglow candidate
  62. GRB 030329: OT candidate
  63. GRB 030329: Optical afterglow candidate
  64. GRB 030328: OT photometry
  65. VLT spectra of GRB 030328
  66. GRB 030328, optical spectroscopy
  67. GRB 030328, optical observations
  68. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  69. GRB 030328: Optical observations
  70. Re: GRB 030328: Finding chart
  71. GRB 030328: Finding chart
  72. GRB 030328: Optical afterglow candidate
  73. GRB030131, BVRcIc field photometry
  74. Possible GRB030323 localized by INTEGRAL
  75. IPN triangulation of GRB030325 (final analysis)
  76. IPN triangulation of GRB030326 (single small error box)
  77. GRB 030323: SARA Optical Observations
  78. IPN triangulation of GRB030325 (single small error box)
  79. GRB030324, optical observations
  80. IPN triangulation of GRB030325 (two small error boxes)
  81. GRB 030324: TAROT optical observations
  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. GRB030324, BVRcIc field photometry
  92. GRB030323, possible optical counterpart
  93. GRB030323, BVRcIc field calibration
  94. GRB 030324 optical observations
  95. GRB 030320: Optical Observations
  96. GRB 030324, optical observations
  97. IPN triangulation of GRB030320B (annulus)
  98. IPN triangulation of GRB030320 (small error box)
  99. IPN triangulation of GRB030320
  100. Possible GRB 030320 localized by INTEGRAL

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