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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.

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

28057 results found.

  1. OT GRB 030329: early UBVRcIc spectral evolution
  2. OT GRB 030329: early spectrum
  3. IPN triangulation of GRB030414 (small error box)
  4. IPN triangulation of GRB030413 (small error box)
  5. Superluminal motion in GRB 030329 (Correction)
  6. Superluminal motion in GRB 030329
  7. GRB030329, optical position
  8. IPN triangulation of GRB030406 (small error box)
  9. IPN triangulation of GRB050403 (small error box)
  10. GRB 030329: BVRI photometry at Asiago
  11. GRB 030329: VLT V-band photometry
  12. Kiso observation of the GRB030329 at April 6
  13. GRB 030329, color evolution
  14. GRB030328, UBVRcIc field photometry
  15. GRB 030329 Optical observations
  16. GRB030329: Kiso B and R band observations
  17. GRB030328: R upper limit after 6 hours by MASTER
  18. SDSS 0.5m PT observations of GRB030329 (correction)
  19. SDSS 0.5m PT observations of GRB030329
  20. GRB030329: final R-band light curve by MASTER
  21. GRB030329, optical observation
  22. GRB030329, new UBVRcIc field photometry
  23. GRB 030329, light curve and SN prediction
  24. GRB 030329, BRI photometry
  25. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  26. GRB030329: Optical observations at Teramo
  27. GRB 030329: Radio observations at GMRT
  28. Further AAVSO V,B,R observations of GRB030329
  29. GRB 030329: Additional Mt. Laguna Optical Observations
  30. GRB 030329: Observations with ANDICAM
  31. GRB030329: further optical photometry and evidence for a light curve discontinuity
  32. triangulation of GRB 030331 (single error box)
  33. GRB 030329: optical observations
  34. Photometry of GRB030329 - Constant OT Magnitude
  35. GRB030329 - OT brightens
  36. GRB 030329, optical photometry
  37. GRB 030324: Optical and NIR Observations
  38. GRB030329: R band light curve by MASTER
  39. GRB030329 - Light curve flattening
  40. GRB 030324, optical search
  41. GRB 030329, optical observations
  42. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  43. GRB030329a: detection by Konus-Wind
  44. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  45. GRB030329, BVRcIc field photometry
  46. GRB030329, SPM optical observations
  47. GRB 030329: Optical decay and synthesis
  48. GRB030329 optical observations
  49. GRB 030329: Optical pre-Imaging
  50. GRB 030329: Upper limit from 5.6 hours before trigger
  51. GRB030328: X-ray Afterglow Observed with Chandra
  52. GRB 030329, R-band observations
  53. GRB 030329: OT B and R photometry, decline rate
  54. GRB030329: Upper limits from recent and historical observations.
  55. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  56. GRB 030329: Optical Afterglow Observations
  57. GRB 030328: optical observations
  58. GRB 030329: Optical afterglow fading
  59. GRB 030328: OT photometry
  60. GRB030328: optical spectroscopy at TNG
  61. GRB030328: optical photometry at the TNG
  62. VLT spectra of GRB 030328
  63. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  64. GRB 030328: Optical observations
  65. GRB030324 optical observation
  66. GRB030131, BVRcIc field photometry
  67. Possible GRB030323 localized by INTEGRAL
  68. GRB030323: Detection on 2003/03/24
  69. IPN triangulation of GRB030326 (single small error box)
  70. IPN triangulation of GRB030325 (two small error boxes)
  71. GRB030323: V, R, I photometry
  72. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  73. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  74. VLT/FORS2 spectra of GRB 030323
  75. GRB030323, optical observations
  76. GRB030324, BVRcIc field photometry
  77. GRB030323, BVRcIc field calibration
  78. IPN triangulation of GRB030320 (small error box)
  79. Possible GRB 030320 localized by INTEGRAL
  80. IPN triangulation of GRB030306 (single small error box - REVISED)
  81. IPN triangulation of GRB030306 (single small error box)
  82. IPN triangulation of GRB030306 (two small error boxes)
  83. GRB030226, BVRc observations
  84. Chandra detection of the X-ray afterglow of GRB 030226
  85. GRB030227: Kiso optical upper limit
  86. GRB030227, BVRcIc field photometry
  87. GRB030226, BVRcIc field calibration
  88. GRB 030228, optical observations
  89. GRB 030227: Confirmed Optical Afterglow (S1-A)
  90. GRB 030227: fading of candidate optical afterglow 'S1-A'
  91. GRB030227:Optical observations
  92. GRB 030227, possible optical counterpart of XMM-Newton source
  93. GRB030227 - faint tentative OT candidate
  94. GRB 030226, optical observations
  95. XMM-Newton observation of GRB030227
  96. GRB030227: Kiso optical observations
  97. GRB 030227: Kyoto optical observation
  98. GRB 030226, optical light curve
  99. GRB030227 localized by INTEGRAL
  100. GRB 030226 : Predicted light curve

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