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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"

35959 results found.

  1. GRB030329 Further RBO Optical Observations
  2. triangulation of GRB 030331 (single error box)
  3. GRB030329 - OT rebrightens
  4. GRB 030329: SARA Optical Observations
  5. AAVSO V & R observations of GRB030329
  6. IPN triangulation of GRB030331 (annulus)
  7. GRB 030329: optical observations
  8. IPN triangulation of GRB030329b (large error box)
  9. GRB 030329: beginning of the new fading phase in optical band
  10. GRB 030329, optical spectroscopy
  11. GRB 030329: fading X-ray afterglow with RXTE
  12. GRB 030329: optical photometry
  13. Photometry of GRB030329 - Constant OT Magnitude
  14. GRB 030329, R-band observations
  15. GRB 030329, R-band light curve
  16. GRB 030329: further optical observations
  17. GRB030329 - OT brightens
  18. GRB 030329: OT observations at Kanazawa
  19. GRB030329 15 GHz radio observation
  20. GRB 030329 RBO V Optical Observations
  21. GRB 030329, optical photometry
  22. GRB030329: Near Infrared Observations
  23. 030331 NOT A GRB
  24. INTEGRAL GRB 030331
  25. GRB 030324: Optical and NIR Observations
  26. GRB 030328, optical photometry
  27. GRB030329: R band light curve by MASTER
  28. GRB030329 - Light curve flattening
  29. GRB 030329: SARA Optical Observations
  30. GRB 030324, optical search
  31. GRB030329 - near contemporaneous optical limits from CONCAM
  32. GRB 030329, optical observations
  33. GRB 030329: Light curve observed during the change of its slope.
  34. GRB030329, BVRcIc field photometry
  35. GRB030329, SPM optical observations
  36. GRB 030329: Optical Decay
  37. Redshift of GRB 030329
  38. GRB030329: ROTSE network observes steepening of decay curve
  39. GRB 030329, optical photometry
  40. GRB 030329: Optical decay and synthesis
  41. GRB 030329: Radio Observations
  42. GRB 030329, optical spectroscopy
  43. GRB 030329: still bright
  44. GRB 030329: Optical pre-Imaging
  45. GRB 030329: visual observations
  46. GRB 030329: Upper limit from 5.6 hours before trigger
  47. GRB030328: R optical observation
  48. GRB 030323: Gemini South VRI obsevations.
  49. GRB030329: Optical observations
  50. GRB 030329, R-band observations, supplement
  51. GRB030329:optical observations by MASTER
  52. GRB 030329: optical observations
  53. GRB 030329, R-band observations
  54. GRB 030329: OT B and R photometry, decline rate
  55. GRB030329: Upper limits from recent and historical observations.
  56. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  57. RXTE detection of GRB 030329 afterglow
  58. GRB 030329: Optical Afterglow Observations
  59. GRB 030329: precise position from Kyoto images
  60. GRB 030328 Optical Observations
  61. GRB 030328: Optical observations
  62. GRB 030328: optical observations
  63. GRB 030329: Optical afterglow fading
  64. GRB 030329 follow-up
  65. GRB 030329: Optical afterglow candidate
  66. GRB 030329: OT candidate
  67. GRB 030329: Optical afterglow candidate
  68. GRB 030328: OT photometry
  69. VLT spectra of GRB 030328
  70. GRB 030328, optical spectroscopy
  71. GRB 030328, optical observations
  72. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  73. GRB 030328: Optical observations
  74. Re: GRB 030328: Finding chart
  75. GRB 030328: Finding chart
  76. GRB 030328: Optical afterglow candidate
  77. GRB030131, BVRcIc field photometry
  78. Possible GRB030323 localized by INTEGRAL
  79. IPN triangulation of GRB030325 (final analysis)
  80. IPN triangulation of GRB030326 (single small error box)
  81. GRB 030323: SARA Optical Observations
  82. IPN triangulation of GRB030325 (single small error box)
  83. GRB030324, optical observations
  84. IPN triangulation of GRB030325 (two small error boxes)
  85. GRB 030324: TAROT optical observations
  86. GRB 030324 (HETE #2641): Optical observations
  87. GRB030324, Optical Observations
  88. GRB030323: Upper limits from recent and historical observations.
  89. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  90. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  91. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  92. VLT/FORS2 spectra of GRB 030323
  93. GRB030323, ROTSE-III detection of possible optical counterpart
  94. GRB030323, optical observations
  95. GRB030324, BVRcIc field photometry
  96. GRB030323, possible optical counterpart
  97. GRB030323, BVRcIc field calibration
  98. GRB 030324 optical observations
  99. GRB 030320: Optical Observations
  100. GRB 030324, optical observations

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