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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"

24629 results found.

  1. GRB 030329: Additional Mt. Laguna Optical Observations
  2. GRB 030329: Observations with ANDICAM
  3. GRB030329: further optical photometry and evidence for a light curve discontinuity
  4. triangulation of GRB 030331 (single error box)
  5. GRB 030329: optical observations
  6. Photometry of GRB030329 - Constant OT Magnitude
  7. GRB030329 - OT brightens
  8. GRB 030329, optical photometry
  9. GRB 030324: Optical and NIR Observations
  10. GRB030329: R band light curve by MASTER
  11. GRB030329 - Light curve flattening
  12. GRB 030324, optical search
  13. GRB 030329, optical observations
  14. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  15. GRB030329a: detection by Konus-Wind
  16. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  17. GRB030329, BVRcIc field photometry
  18. GRB030329, SPM optical observations
  19. GRB 030329: Optical decay and synthesis
  20. GRB030329 optical observations
  21. GRB 030329: Optical pre-Imaging
  22. GRB 030329: Upper limit from 5.6 hours before trigger
  23. GRB030328: X-ray Afterglow Observed with Chandra
  24. GRB 030329, R-band observations
  25. GRB 030329: OT B and R photometry, decline rate
  26. GRB030329: Upper limits from recent and historical observations.
  27. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  28. GRB 030329: Optical Afterglow Observations
  29. GRB 030328: optical observations
  30. GRB 030329: Optical afterglow fading
  31. GRB 030328: OT photometry
  32. GRB030328: optical spectroscopy at TNG
  33. GRB030328: optical photometry at the TNG
  34. VLT spectra of GRB 030328
  35. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  36. GRB 030328: Optical observations
  37. GRB030324 optical observation
  38. GRB030131, BVRcIc field photometry
  39. Possible GRB030323 localized by INTEGRAL
  40. GRB030323: Detection on 2003/03/24
  41. IPN triangulation of GRB030326 (single small error box)
  42. IPN triangulation of GRB030325 (two small error boxes)
  43. GRB030323: V, R, I photometry
  44. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  45. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  46. VLT/FORS2 spectra of GRB 030323
  47. GRB030323, optical observations
  48. GRB030324, BVRcIc field photometry
  49. GRB030323, BVRcIc field calibration
  50. IPN triangulation of GRB030320 (small error box)
  51. Possible GRB 030320 localized by INTEGRAL
  52. IPN triangulation of GRB030306 (single small error box - REVISED)
  53. IPN triangulation of GRB030306 (single small error box)
  54. IPN triangulation of GRB030306 (two small error boxes)
  55. GRB030226, BVRc observations
  56. Chandra detection of the X-ray afterglow of GRB 030226
  57. GRB030227: Kiso optical upper limit
  58. GRB030227, BVRcIc field photometry
  59. GRB030226, BVRcIc field calibration
  60. GRB 030228, optical observations
  61. GRB 030227: Confirmed Optical Afterglow (S1-A)
  62. GRB 030227: fading of candidate optical afterglow 'S1-A'
  63. GRB030227:Optical observations
  64. GRB 030227, possible optical counterpart of XMM-Newton source
  65. GRB030227 - faint tentative OT candidate
  66. GRB 030226, optical observations
  67. XMM-Newton observation of GRB030227
  68. GRB030227: Kiso optical observations
  69. GRB 030227: Kyoto optical observation
  70. GRB 030226, optical light curve
  71. GRB030227 localized by INTEGRAL
  72. GRB 030226 : Predicted light curve
  73. GRB030226: ESI spectroscopy
  74. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  75. GRB 030226 simultaneous optical observations
  76. GRB 030226, optical observations
  77. GRB030226: Optical decay index
  78. GRB 030226 Optical Spectra and R,I,z' Imaging
  79. GRB: Non-Referencing of GCN Circulars.
  80. IPN triangulation of GRB030217 (small error box)
  81. GRB 030131: marginal optical detection
  82. GRB 030204: Optical Observations
  83. GRB030204 field photometry
  84. GRB020819: Kiso R and I band observations
  85. GRB030131: Candidate Optical Afterglow
  86. IPN triangulation of GRB030204 (small error box)
  87. GRB 030131, optical observations
  88. GRB 030131: afterglow candidate
  89. GRB 030115, late-time optical observations
  90. GRB030131: corrected INTEGRAL position
  91. GRB 020819: Host galaxy at Radio Position
  92. IPN triangulation of GRB030131
  93. GRB 030131 optical observations
  94. GRB 030131 optical observations
  95. A long GRB detected by INTEGRAL
  96. GRB030115: 1.2 mm upper limits with MAMBO @ IRAM 30m
  97. GRB 030115, simultaneous observations by BOOTES-1
  98. GRB 030115: IR observations with IRSF/SIRIUS
  99. IPN triangulation of GRB030115C (large error box)
  100. GRB030115, afterglow candidate

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