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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').
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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.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36181 results found.

  1. GRB030324, optical observations
  2. IPN triangulation of GRB030325 (two small error boxes)
  3. GRB 030324: TAROT optical observations
  4. GRB 030324 (HETE #2641): Optical observations
  5. GRB030324, Optical Observations
  6. GRB030323: Upper limits from recent and historical observations.
  7. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  8. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  9. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  10. VLT/FORS2 spectra of GRB 030323
  11. GRB030323, ROTSE-III detection of possible optical counterpart
  12. GRB030323, optical observations
  13. GRB030324, BVRcIc field photometry
  14. GRB030323, possible optical counterpart
  15. GRB030323, BVRcIc field calibration
  16. GRB 030324 optical observations
  17. GRB 030320: Optical Observations
  18. GRB 030324, optical observations
  19. IPN triangulation of GRB030320B (annulus)
  20. IPN triangulation of GRB030320 (small error box)
  21. IPN triangulation of GRB030320
  22. Possible GRB 030320 localized by INTEGRAL
  23. IPN upper limit to a GRB associated with SN2003L
  24. IPN triangulation of GRB030317 (annulus)
  25. IPN triangulation of GRB030307 (annulus)
  26. GRB 030227: Optical limit at RIKEN
  27. GRB 030226 Optical observations
  28. IPN triangulation of GRB030306 (single small error box - REVISED)
  29. GRB030226: Optical observations at Asiago
  30. IPN triangulation of GRB030306 (single small error box)
  31. IPN triangulation of GRB030306 (two small error boxes)
  32. IPN triangulation of GRB030306 (intense; annulus only so far)
  33. GRB 030226: Optical observations
  34. IPN triangulation of GRB030304 (annulus)
  35. GRB 030227: Optical observations
  36. GRB030226, BVRc observations
  37. Chandra detection of the X-ray afterglow of GRB 030226
  38. GRB 030226, further optical/NIR imaging
  39. GRB030227, optical observations
  40. GRB 030226: Ic Observations
  41. GRB030227: Kiso optical upper limit
  42. IPN triangulation of GRB030301 (annulus)
  43. IPN triangulation of GRB030228 (annulus)
  44. GRB030227, BVRcIc field photometry
  45. GRB030226, BVRcIc field calibration
  46. GRB 030227 optical afterglow
  47. 030302: NOT A GRB
  48. 030228: NOT A GRB
  49. GRB 030228, optical observations
  50. GRB 030226: Steep Decline
  51. GRB 030227: Confirmed Optical Afterglow (S1-A)
  52. GRB 030226: R band polarimetric observations
  53. GRB 030226: Optical observations
  54. GRB 030227: fading of candidate optical afterglow 'S1-A'
  55. GRB030227:Optical observations
  56. GRB 20030226: Upper limits from recent and historical observations
  57. GRB 030227, possible optical counterpart of XMM-Newton source
  58. GRB030227 - faint tentative OT candidate
  59. GRB 030226, optical observations
  60. GRB030227: Kiso optical observations
  61. GRB 030227: Kyoto optical observation
  62. GRB 030226, optical light curve
  63. GRB 030226 spectroscopy
  64. Possible break in the GRB 030226 light curve
  65. GRB 030226 : Predicted light curve
  66. IPN triangulation of GRB030225 (annulus)
  67. GRB 030226: Confirmed decay index
  68. GRB030226: ESI spectroscopy
  69. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  70. GRB 030226 simultaneous optical observations
  71. Two absorption systems in GRB 030226
  72. GRB 030226, optical observations
  73. GRB 030226 Optical Spectra and R,I,z' Imaging
  74. GRB 030226, optical observations
  75. GRB 030226: Optical afterglow
  76. GRB 030217: Optical Observations at 4, 5, and 6 Days
  77. IPN triangulation of GRB030223 (annulus)
  78. IPN triangulation of GRB030220 (annulus)
  79. GRB: Non-Referencing of GCN Circulars.
  80. IPN triangulation of GRB030218 (annulus)
  81. IPN triangulation of GRB030217 (small error box)
  82. IPN triangulation of GRB030215C (annulus)
  83. IPN triangulation of GRB030217 (annulus)
  84. IPN triangulation of GRB030216 (annulus)
  85. IPN triangulation of GRB030215A and GRB030215B (annuli)
  86. GRB030115, WSRT radio observations - correction to GCN 1864
  87. GRB 030131: marginal optical detection
  88. GRB030115, WSRT radio observations
  89. IPN triangulation of GRB030206 (annulus)
  90. IPN triangulation of GRB030208 (annulus)
  91. GRB 030204: Optical Observations
  92. GRB030204 field photometry
  93. GRB020819: Kiso R and I band observations
  94. GRB 030204: Correction to GCN 1856
  95. GRB 030115: Optical Observations
  96. GRB 030204, optical observations
  97. IPN triangulation of GRB030204 (small error box)
  98. IPN triangulation of GRB030202 (annulus)
  99. GRB 030131, optical observations
  100. GRB030131: Kiso optical limit for corrected position

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