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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"

28053 results found.

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

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