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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"

24664 results found.

  1. GRB030329: optical polarization
  2. IPN triangulation of GRB030422 (two large error boxes)
  3. GRB030329, optical observation
  4. MASTER:optical observations GRB030418
  5. MASTER:optical observations probable GRB030414
  6. GRB030418: Kiso near infrared observations
  7. GRB 030418: Optical afterglow
  8. OT GRB 030329: early UBVRcIc spectral evolution
  9. OT GRB 030329: early spectrum
  10. IPN triangulation of GRB030414 (small error box)
  11. IPN triangulation of GRB030413 (small error box)
  12. Superluminal motion in GRB 030329 (Correction)
  13. Superluminal motion in GRB 030329
  14. GRB030329, optical position
  15. IPN triangulation of GRB030406 (small error box)
  16. IPN triangulation of GRB050403 (small error box)
  17. GRB 030329: BVRI photometry at Asiago
  18. GRB 030329: VLT V-band photometry
  19. Kiso observation of the GRB030329 at April 6
  20. GRB 030329, color evolution
  21. GRB030328, UBVRcIc field photometry
  22. GRB 030329 Optical observations
  23. GRB030329: Kiso B and R band observations
  24. GRB030328: R upper limit after 6 hours by MASTER
  25. SDSS 0.5m PT observations of GRB030329 (correction)
  26. SDSS 0.5m PT observations of GRB030329
  27. GRB030329: final R-band light curve by MASTER
  28. GRB030329, optical observation
  29. GRB030329, new UBVRcIc field photometry
  30. GRB 030329, light curve and SN prediction
  31. GRB 030329, BRI photometry
  32. GRB030328: Full Observation, X-ray Fading and Spectrum Measured
  33. GRB030329: Optical observations at Teramo
  34. GRB 030329: Radio observations at GMRT
  35. Further AAVSO V,B,R observations of GRB030329
  36. GRB 030329: Additional Mt. Laguna Optical Observations
  37. GRB 030329: Observations with ANDICAM
  38. GRB030329: further optical photometry and evidence for a light curve discontinuity
  39. triangulation of GRB 030331 (single error box)
  40. GRB 030329: optical observations
  41. Photometry of GRB030329 - Constant OT Magnitude
  42. GRB030329 - OT brightens
  43. GRB 030329, optical photometry
  44. GRB 030324: Optical and NIR Observations
  45. GRB030329: R band light curve by MASTER
  46. GRB030329 - Light curve flattening
  47. GRB 030324, optical search
  48. GRB 030329, optical observations
  49. GRB030328: X-ray Fading and Spectrum Measured with Chandra
  50. GRB030329a: detection by Konus-Wind
  51. GRB030329b: detection by Konus-Wind and Helicon-CoronasF
  52. GRB030329, BVRcIc field photometry
  53. GRB030329, SPM optical observations
  54. GRB 030329: Optical decay and synthesis
  55. GRB030329 optical observations
  56. GRB 030329: Optical pre-Imaging
  57. GRB 030329: Upper limit from 5.6 hours before trigger
  58. GRB030328: X-ray Afterglow Observed with Chandra
  59. GRB 030329, R-band observations
  60. GRB 030329: OT B and R photometry, decline rate
  61. GRB030329: Upper limits from recent and historical observations.
  62. GRB030329 (=H2652): A Long, Extremely Bright GRB Localized by the HETE WXM and SXC
  63. GRB 030329: Optical Afterglow Observations
  64. GRB 030328: optical observations
  65. GRB 030329: Optical afterglow fading
  66. GRB 030328: OT photometry
  67. GRB030328: optical spectroscopy at TNG
  68. GRB030328: optical photometry at the TNG
  69. VLT spectra of GRB 030328
  70. GRB030328 (=H2650): A Long, Bright GRB Localized by the HETE WXM and SXC
  71. GRB 030328: Optical observations
  72. GRB030324 optical observation
  73. GRB030131, BVRcIc field photometry
  74. Possible GRB030323 localized by INTEGRAL
  75. GRB030323: Detection on 2003/03/24
  76. IPN triangulation of GRB030326 (single small error box)
  77. IPN triangulation of GRB030325 (two small error boxes)
  78. GRB030323: V, R, I photometry
  79. GRB030323 (=H2640): A Faint, Long GRB Localized by the HETE WXM and SXC
  80. GRB030324 (=H2641): A Long GRB Localized in Real Time by the HETE WXM
  81. VLT/FORS2 spectra of GRB 030323
  82. GRB030323, optical observations
  83. GRB030324, BVRcIc field photometry
  84. GRB030323, BVRcIc field calibration
  85. IPN triangulation of GRB030320 (small error box)
  86. Possible GRB 030320 localized by INTEGRAL
  87. IPN triangulation of GRB030306 (single small error box - REVISED)
  88. IPN triangulation of GRB030306 (single small error box)
  89. IPN triangulation of GRB030306 (two small error boxes)
  90. GRB030226, BVRc observations
  91. Chandra detection of the X-ray afterglow of GRB 030226
  92. GRB030227: Kiso optical upper limit
  93. GRB030227, BVRcIc field photometry
  94. GRB030226, BVRcIc field calibration
  95. GRB 030228, optical observations
  96. GRB 030227: Confirmed Optical Afterglow (S1-A)
  97. GRB 030227: fading of candidate optical afterglow 'S1-A'
  98. GRB030227:Optical observations
  99. GRB 030227, possible optical counterpart of XMM-Newton source
  100. GRB030227 - faint tentative OT candidate

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