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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"

36184 results found.

  1. IPN triangulation of GRB030326 (single small error box)
  2. GRB 030323: SARA Optical Observations
  3. IPN triangulation of GRB030325 (single small error box)
  4. GRB030324, optical observations
  5. IPN triangulation of GRB030325 (two small error boxes)
  6. GRB 030324: TAROT optical observations
  7. GRB 030324 (HETE #2641): Optical observations
  8. GRB030324, Optical Observations
  9. GRB030323: Upper limits from recent and historical observations.
  10. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  11. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  12. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  13. VLT/FORS2 spectra of GRB 030323
  14. GRB030323, ROTSE-III detection of possible optical counterpart
  15. GRB030323, optical observations
  16. GRB030324, BVRcIc field photometry
  17. GRB030323, possible optical counterpart
  18. GRB030323, BVRcIc field calibration
  19. GRB 030324 optical observations
  20. GRB 030320: Optical Observations
  21. GRB 030324, optical observations
  22. IPN triangulation of GRB030320B (annulus)
  23. IPN triangulation of GRB030320 (small error box)
  24. IPN triangulation of GRB030320
  25. Possible GRB 030320 localized by INTEGRAL
  26. IPN upper limit to a GRB associated with SN2003L
  27. IPN triangulation of GRB030317 (annulus)
  28. IPN triangulation of GRB030307 (annulus)
  29. GRB 030227: Optical limit at RIKEN
  30. GRB 030226 Optical observations
  31. IPN triangulation of GRB030306 (single small error box - REVISED)
  32. GRB030226: Optical observations at Asiago
  33. IPN triangulation of GRB030306 (single small error box)
  34. IPN triangulation of GRB030306 (two small error boxes)
  35. IPN triangulation of GRB030306 (intense; annulus only so far)
  36. GRB 030226: Optical observations
  37. IPN triangulation of GRB030304 (annulus)
  38. GRB 030227: Optical observations
  39. GRB030226, BVRc observations
  40. Chandra detection of the X-ray afterglow of GRB 030226
  41. GRB 030226, further optical/NIR imaging
  42. GRB030227, optical observations
  43. GRB 030226: Ic Observations
  44. GRB030227: Kiso optical upper limit
  45. IPN triangulation of GRB030301 (annulus)
  46. IPN triangulation of GRB030228 (annulus)
  47. GRB030227, BVRcIc field photometry
  48. GRB030226, BVRcIc field calibration
  49. GRB 030227 optical afterglow
  50. 030302: NOT A GRB
  51. 030228: NOT A GRB
  52. GRB 030228, optical observations
  53. GRB 030226: Steep Decline
  54. GRB 030227: Confirmed Optical Afterglow (S1-A)
  55. GRB 030226: R band polarimetric observations
  56. GRB 030226: Optical observations
  57. GRB 030227: fading of candidate optical afterglow 'S1-A'
  58. GRB030227:Optical observations
  59. GRB 20030226: Upper limits from recent and historical observations
  60. GRB 030227, possible optical counterpart of XMM-Newton source
  61. GRB030227 - faint tentative OT candidate
  62. GRB 030226, optical observations
  63. GRB030227: Kiso optical observations
  64. GRB 030227: Kyoto optical observation
  65. GRB 030226, optical light curve
  66. GRB 030226 spectroscopy
  67. Possible break in the GRB 030226 light curve
  68. GRB 030226 : Predicted light curve
  69. IPN triangulation of GRB030225 (annulus)
  70. GRB 030226: Confirmed decay index
  71. GRB030226: ESI spectroscopy
  72. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  73. GRB 030226 simultaneous optical observations
  74. Two absorption systems in GRB 030226
  75. GRB 030226, optical observations
  76. GRB 030226 Optical Spectra and R,I,z' Imaging
  77. GRB 030226, optical observations
  78. GRB 030226: Optical afterglow
  79. GRB 030217: Optical Observations at 4, 5, and 6 Days
  80. IPN triangulation of GRB030223 (annulus)
  81. IPN triangulation of GRB030220 (annulus)
  82. GRB: Non-Referencing of GCN Circulars.
  83. IPN triangulation of GRB030218 (annulus)
  84. IPN triangulation of GRB030217 (small error box)
  85. IPN triangulation of GRB030215C (annulus)
  86. IPN triangulation of GRB030217 (annulus)
  87. IPN triangulation of GRB030216 (annulus)
  88. IPN triangulation of GRB030215A and GRB030215B (annuli)
  89. GRB030115, WSRT radio observations - correction to GCN 1864
  90. GRB 030131: marginal optical detection
  91. GRB030115, WSRT radio observations
  92. IPN triangulation of GRB030206 (annulus)
  93. IPN triangulation of GRB030208 (annulus)
  94. GRB 030204: Optical Observations
  95. GRB030204 field photometry
  96. GRB020819: Kiso R and I band observations
  97. GRB 030204: Correction to GCN 1856
  98. GRB 030115: Optical Observations
  99. GRB 030204, optical observations
  100. IPN triangulation of GRB030204 (small error box)

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