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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"

37746 results found.

  1. GRB 030329, R-band observations
  2. GRB 030329, R-band light curve
  3. GRB 030329: further optical observations
  4. GRB030329 - OT brightens
  5. GRB 030329: OT observations at Kanazawa
  6. GRB030329 15 GHz radio observation
  7. GRB 030329 RBO V Optical Observations
  8. GRB 030329, optical photometry
  9. GRB030329: Near Infrared Observations
  10. 030331 NOT A GRB
  11. INTEGRAL GRB 030331
  12. GRB 030324: Optical and NIR Observations
  13. GRB 030328, optical photometry
  14. GRB030329: R band light curve by MASTER
  15. GRB030329 - Light curve flattening
  16. GRB 030329: SARA Optical Observations
  17. GRB 030324, optical search
  18. GRB030329 - near contemporaneous optical limits from CONCAM
  19. GRB 030329, optical observations
  20. GRB 030329: Light curve observed during the change of its slope.
  21. GRB030329, BVRcIc field photometry
  22. GRB030329, SPM optical observations
  23. GRB 030329: Optical Decay
  24. Redshift of GRB 030329
  25. GRB030329: ROTSE network observes steepening of decay curve
  26. GRB 030329, optical photometry
  27. GRB 030329: Optical decay and synthesis
  28. GRB 030329: Radio Observations
  29. GRB 030329, optical spectroscopy
  30. GRB 030329: still bright
  31. GRB 030329: Optical pre-Imaging
  32. GRB 030329: visual observations
  33. GRB 030329: Upper limit from 5.6 hours before trigger
  34. GRB030328: R optical observation
  35. GRB 030323: Gemini South VRI obsevations.
  36. GRB030329: Optical observations
  37. GRB 030329, R-band observations, supplement
  38. GRB030329:optical observations by MASTER
  39. GRB 030329: optical observations
  40. GRB 030329, R-band observations
  41. GRB 030329: OT B and R photometry, decline rate
  42. GRB030329: Upper limits from recent and historical observations.
  43. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  44. RXTE detection of GRB 030329 afterglow
  45. GRB 030329: Optical Afterglow Observations
  46. GRB 030329: precise position from Kyoto images
  47. GRB 030328 Optical Observations
  48. GRB 030328: Optical observations
  49. GRB 030328: optical observations
  50. GRB 030329: Optical afterglow fading
  51. GRB 030329 follow-up
  52. GRB 030329: Optical afterglow candidate
  53. GRB 030329: OT candidate
  54. GRB 030329: Optical afterglow candidate
  55. GRB 030328: OT photometry
  56. VLT spectra of GRB 030328
  57. GRB 030328, optical spectroscopy
  58. GRB 030328, optical observations
  59. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  60. GRB 030328: Optical observations
  61. Re: GRB 030328: Finding chart
  62. GRB 030328: Finding chart
  63. GRB 030328: Optical afterglow candidate
  64. GRB030131, BVRcIc field photometry
  65. Possible GRB030323 localized by INTEGRAL
  66. IPN triangulation of GRB030325 (final analysis)
  67. IPN triangulation of GRB030326 (single small error box)
  68. GRB 030323: SARA Optical Observations
  69. IPN triangulation of GRB030325 (single small error box)
  70. GRB030324, optical observations
  71. IPN triangulation of GRB030325 (two small error boxes)
  72. GRB 030324: TAROT optical observations
  73. GRB 030324 (HETE #2641): Optical observations
  74. GRB030324, Optical Observations
  75. GRB030323: Upper limits from recent and historical observations.
  76. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  77. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  78. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  79. VLT/FORS2 spectra of GRB 030323
  80. GRB030323, ROTSE-III detection of possible optical counterpart
  81. GRB030323, optical observations
  82. GRB030324, BVRcIc field photometry
  83. GRB030323, possible optical counterpart
  84. GRB030323, BVRcIc field calibration
  85. GRB 030324 optical observations
  86. GRB 030320: Optical Observations
  87. GRB 030324, optical observations
  88. IPN triangulation of GRB030320B (annulus)
  89. IPN triangulation of GRB030320 (small error box)
  90. IPN triangulation of GRB030320
  91. Possible GRB 030320 localized by INTEGRAL
  92. IPN upper limit to a GRB associated with SN2003L
  93. IPN triangulation of GRB030317 (annulus)
  94. IPN triangulation of GRB030307 (annulus)
  95. GRB 030227: Optical limit at RIKEN
  96. GRB 030226 Optical observations
  97. IPN triangulation of GRB030306 (single small error box - REVISED)
  98. GRB030226: Optical observations at Asiago
  99. IPN triangulation of GRB030306 (single small error box)
  100. IPN triangulation of GRB030306 (two small error boxes)

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