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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"

28054 results found.

  1. IPN triangulation of GRB030413 (small error box)
  2. Superluminal motion in GRB 030329 (Correction)
  3. Superluminal motion in GRB 030329
  4. GRB030329, optical position
  5. IPN triangulation of GRB030406 (small error box)
  6. IPN triangulation of GRB050403 (small error box)
  7. GRB 030329: BVRI photometry at Asiago
  8. GRB 030329: VLT V-band photometry
  9. Kiso observation of the GRB030329 at April 6
  10. GRB 030329, color evolution
  11. GRB030328, UBVRcIc field photometry
  12. GRB 030329 Optical observations
  13. GRB030329: Kiso B and R band observations
  14. GRB030328: R upper limit after 6 hours by MASTER
  15. SDSS 0.5m PT observations of GRB030329 (correction)
  16. SDSS 0.5m PT observations of GRB030329
  17. GRB030329: final R-band light curve by MASTER
  18. GRB030329, optical observation
  19. GRB030329, new UBVRcIc field photometry
  20. GRB 030329, light curve and SN prediction
  21. GRB 030329, BRI photometry
  22. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  23. GRB030329: Optical observations at Teramo
  24. GRB 030329: Radio observations at GMRT
  25. Further AAVSO V,B,R observations of GRB030329
  26. GRB 030329: Additional Mt. Laguna Optical Observations
  27. GRB 030329: Observations with ANDICAM
  28. GRB030329: further optical photometry and evidence for a light curve discontinuity
  29. triangulation of GRB 030331 (single error box)
  30. GRB 030329: optical observations
  31. Photometry of GRB030329 - Constant OT Magnitude
  32. GRB030329 - OT brightens
  33. GRB 030329, optical photometry
  34. GRB 030324: Optical and NIR Observations
  35. GRB030329: R band light curve by MASTER
  36. GRB030329 - Light curve flattening
  37. GRB 030324, optical search
  38. GRB 030329, optical observations
  39. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  40. GRB030329a: detection by Konus-Wind
  41. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  42. GRB030329, BVRcIc field photometry
  43. GRB030329, SPM optical observations
  44. GRB 030329: Optical decay and synthesis
  45. GRB030329 optical observations
  46. GRB 030329: Optical pre-Imaging
  47. GRB 030329: Upper limit from 5.6 hours before trigger
  48. GRB030328: X-ray Afterglow Observed with Chandra
  49. GRB 030329, R-band observations
  50. GRB 030329: OT B and R photometry, decline rate
  51. GRB030329: Upper limits from recent and historical observations.
  52. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  53. GRB 030329: Optical Afterglow Observations
  54. GRB 030328: optical observations
  55. GRB 030329: Optical afterglow fading
  56. GRB 030328: OT photometry
  57. GRB030328: optical spectroscopy at TNG
  58. GRB030328: optical photometry at the TNG
  59. VLT spectra of GRB 030328
  60. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  61. GRB 030328: Optical observations
  62. GRB030324 optical observation
  63. GRB030131, BVRcIc field photometry
  64. Possible GRB030323 localized by INTEGRAL
  65. GRB030323: Detection on 2003/03/24
  66. IPN triangulation of GRB030326 (single small error box)
  67. IPN triangulation of GRB030325 (two small error boxes)
  68. GRB030323: V, R, I photometry
  69. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  70. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  71. VLT/FORS2 spectra of GRB 030323
  72. GRB030323, optical observations
  73. GRB030324, BVRcIc field photometry
  74. GRB030323, BVRcIc field calibration
  75. IPN triangulation of GRB030320 (small error box)
  76. Possible GRB 030320 localized by INTEGRAL
  77. IPN triangulation of GRB030306 (single small error box - REVISED)
  78. IPN triangulation of GRB030306 (single small error box)
  79. IPN triangulation of GRB030306 (two small error boxes)
  80. GRB030226, BVRc observations
  81. Chandra detection of the X-ray afterglow of GRB 030226
  82. GRB030227: Kiso optical upper limit
  83. GRB030227, BVRcIc field photometry
  84. GRB030226, BVRcIc field calibration
  85. GRB 030228, optical observations
  86. GRB 030227: Confirmed Optical Afterglow (S1-A)
  87. GRB 030227: fading of candidate optical afterglow 'S1-A'
  88. GRB030227:Optical observations
  89. GRB 030227, possible optical counterpart of XMM-Newton source
  90. GRB030227 - faint tentative OT candidate
  91. GRB 030226, optical observations
  92. XMM-Newton observation of GRB030227
  93. GRB030227: Kiso optical observations
  94. GRB 030227: Kyoto optical observation
  95. GRB 030226, optical light curve
  96. GRB030227 localized by INTEGRAL
  97. GRB 030226 : Predicted light curve
  98. GRB030226: ESI spectroscopy
  99. GRB030226 (=U10893): A Long GRB Localized by the HETE WXM and SXC
  100. GRB 030226 simultaneous optical observations

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