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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"

35954 results found.

  1. IPN triangulation of GRB030331 (annulus)
  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. Photometry of GRB030329 - Constant OT Magnitude
  9. GRB 030329, R-band observations
  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. 030331 NOT A GRB
  19. INTEGRAL GRB 030331
  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. GRB 030329, optical observations
  28. GRB 030329: Light curve observed during the change of its slope.
  29. GRB030329, BVRcIc field photometry
  30. GRB030329, SPM optical observations
  31. GRB 030329: Optical Decay
  32. Redshift of GRB 030329
  33. GRB030329: ROTSE network observes steepening of decay curve
  34. GRB 030329, optical photometry
  35. GRB 030329: Optical decay and synthesis
  36. GRB 030329: Radio Observations
  37. GRB 030329, optical spectroscopy
  38. GRB 030329: still bright
  39. GRB 030329: Optical pre-Imaging
  40. GRB 030329: visual observations
  41. GRB 030329: Upper limit from 5.6 hours before trigger
  42. GRB030328: R optical observation
  43. GRB 030323: Gemini South VRI obsevations.
  44. GRB030329: Optical observations
  45. GRB 030329, R-band observations, supplement
  46. GRB030329:optical observations by MASTER
  47. GRB 030329: optical observations
  48. GRB 030329, R-band observations
  49. GRB 030329: OT B and R photometry, decline rate
  50. GRB030329: Upper limits from recent and historical observations.
  51. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  52. RXTE detection of GRB 030329 afterglow
  53. GRB 030329: Optical Afterglow Observations
  54. GRB 030329: precise position from Kyoto images
  55. GRB 030328 Optical Observations
  56. GRB 030328: Optical observations
  57. GRB 030328: optical observations
  58. GRB 030329: Optical afterglow fading
  59. GRB 030329 follow-up
  60. GRB 030329: Optical afterglow candidate
  61. GRB 030329: OT candidate
  62. GRB 030329: Optical afterglow candidate
  63. GRB 030328: OT photometry
  64. VLT spectra of GRB 030328
  65. GRB 030328, optical spectroscopy
  66. GRB 030328, optical observations
  67. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  68. GRB 030328: Optical observations
  69. Re: GRB 030328: Finding chart
  70. GRB 030328: Finding chart
  71. GRB 030328: Optical afterglow candidate
  72. GRB030131, BVRcIc field photometry
  73. Possible GRB030323 localized by INTEGRAL
  74. IPN triangulation of GRB030325 (final analysis)
  75. IPN triangulation of GRB030326 (single small error box)
  76. GRB 030323: SARA Optical Observations
  77. IPN triangulation of GRB030325 (single small error box)
  78. GRB030324, optical observations
  79. IPN triangulation of GRB030325 (two small error boxes)
  80. GRB 030324: TAROT optical observations
  81. GRB 030324 (HETE #2641): Optical observations
  82. GRB030324, Optical Observations
  83. GRB030323: Upper limits from recent and historical observations.
  84. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  85. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  86. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  87. VLT/FORS2 spectra of GRB 030323
  88. GRB030323, ROTSE-III detection of possible optical counterpart
  89. GRB030323, optical observations
  90. GRB030324, BVRcIc field photometry
  91. GRB030323, possible optical counterpart
  92. GRB030323, BVRcIc field calibration
  93. GRB 030324 optical observations
  94. GRB 030320: Optical Observations
  95. GRB 030324, optical observations
  96. IPN triangulation of GRB030320B (annulus)
  97. IPN triangulation of GRB030320 (small error box)
  98. IPN triangulation of GRB030320
  99. Possible GRB 030320 localized by INTEGRAL
  100. IPN upper limit to a GRB associated with SN2003L

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